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Variable Resolution Discretization In The Joint Space, Christopher K. Monson, Kevin Seppi, David Wingate, Todd S. Peterson Dec 2004

Variable Resolution Discretization In The Joint Space, Christopher K. Monson, Kevin Seppi, David Wingate, Todd S. Peterson

Faculty Publications

We present JoSTLe, an algorithm that performs value iteration on control problems with continuous actions, allowing this useful reinforcement learning technique to be applied to problems where a priori action discretization is inadequate. The algorithm is an extension of a variable resolution technique that works for problems with continuous states and discrete actions. Results are given that indicate that JoSTLe is a promising step toward reinforcement learning in a fully continuous domain.


A Bayesian Technique For Task Localization In Multiple Goal Markov Decision Processes, James Carroll, Kevin Seppi Dec 2004

A Bayesian Technique For Task Localization In Multiple Goal Markov Decision Processes, James Carroll, Kevin Seppi

Faculty Publications

In a reinforcement learning task library system for Multiple Goal Markov Decision Process (MGMDP), localization in the task space allows the agent to determine whether a given task is already in its library in order to exploit previously learned experience. Task localization in MGMDPs can be accomplished through a Bayesian approach, however a trivial approach fails when the rewards are not distributed normally. This can be overcome through our Bayesian Task Localization Technique (BTLT).


Atomic Force Microscope Conductivity Measurements Of Single Ferritin Molecules, Degao Xu Dec 2004

Atomic Force Microscope Conductivity Measurements Of Single Ferritin Molecules, Degao Xu

Theses and Dissertations

Conductive Atomic Force Microscope (c-AFM) was used to measure the conductivity of single horse spleen ferritin (HoSF) and azotobacter vinelandii bacterial ferritin (AvBF) molecules deposited on flat gold surfaces. A 500 micron diameter gold ball was also used as a contact probe to measure the conductivity of a thin film of ferritin molecules. The average current measured for holo HoSF was 13 and 5 times larger than that measured for apo HoSF as measured by c-AFM at 1V and gold ball at 2V and respectively, which indicates that the core of ferritin is more conductive than the protein shell and …


Hyperbolic Sets That Are Not Locally Maximal, Todd L. Fisher Dec 2004

Hyperbolic Sets That Are Not Locally Maximal, Todd L. Fisher

Faculty Publications

This paper addresses the following topics relating to the structure of hyperbolic sets: First, hyperbolic sets that are not contained in locally maximal hyperbolic sets. Second, the existence of a Markov partition for a hyperbolic set. We construct new examples of hyperbolic sets which are not contained in locally maximal hyperbolic sets. The first example is robust under perturbations and can be constructed on any compact manifold of dimension greater than one. The second example is robust, topologically transitive, and constructed on a 4-dimensional manifold. The third example is volume preserving and constructed on R4. We show that every hyperbolic …


Wave Scattering From Infinite Cylindrical Obstacles Of Arbitrary Cross-Section, Matthew B. Weber Dec 2004

Wave Scattering From Infinite Cylindrical Obstacles Of Arbitrary Cross-Section, Matthew B. Weber

Theses and Dissertations

In this work the scattering of an incident plane wave propagating along a plane perpendicular to the xy-plane is studied. The wave is scattered from an infinitely long cylindrical object of arbitrary cross-section. Due to the arbitrary geometry of the obstacle, a finite differences numerical method is employed to approximate the solution of the scattering problems. The wave equation is expressed in terms of generalized curvilinear coordinates. Boundary conforming grids are generated using elliptic grid generators. Then, a explicit marching in time scheme is implemented over these grids. It is found that as time grows the numerical solution converges to …


Ip Algorithm Applied To Proteomics Data, Christopher Lee Green Nov 2004

Ip Algorithm Applied To Proteomics Data, Christopher Lee Green

Theses and Dissertations

Mass spectrometry has been used extensively in recent years as a valuable tool in the study of proteomics. However, the data thus produced exhibits hyper-dimensionality. Reducing the dimensionality of the data often requires the imposition of many assumptions which can be harmful to subsequent analysis. The IP algorithm is a dimension reduction algorithm, similar in purpose to latent variable analysis. It is based on the principle of maximum entropy and therefore imposes a minimum number of assumptions on the data. Partial Least Squares (PLS) is an algorithm commonly used with proteomics data from mass spectrometry in order to reduce the …


Pluton Zonation Unveiled By Gamma-Ray Spectrometry And Magnetic Susceptibility; A Case Study Of The Sheeprock Granite, Western, Utah, Paul D. Richardson Nov 2004

Pluton Zonation Unveiled By Gamma-Ray Spectrometry And Magnetic Susceptibility; A Case Study Of The Sheeprock Granite, Western, Utah, Paul D. Richardson

Theses and Dissertations

A radiometric survey of the zoned 21 Ma, A-type Sheeprock granite, western Utah, combined with measurements of magnetic susceptibility and field observations were analyzed using a geographic information system. The intrusion spans 25 square km and is roughly eliptical in shape with its long axis trending northwest. Concentration maps (composed of more than 500 survey stations) of eU, eTh, texture, magnetic susceptibility, color, and joint density help to constrain magmatic and post-magmatic processes related to its chemical and physical zonation. Uranium ranges from 3.9 to 26.9 ppm (mean 12.7) and thorium from 1.7 to 125.7 ppm (mean 45.5). Similarities in …


Target-Dominant Chinese-English Machine Translation, Dan Su Nov 2004

Target-Dominant Chinese-English Machine Translation, Dan Su

Theses and Dissertations

Information exchange is increasing rapidly with the advent of globalization. As the language spoken by the most people in today's world, Chinese will play an important role in information exchange in the future. Therefore, we need an efficient and practical means to access the increasingly large volume of Chinese data. This thesis describes a target-dominant Chinese-English machine translation system, which can translate a given Chinese news sentence into English. We conjecture that we can improve the state of the art of MT using a TDMT approach. This system has participated in the NIST (National Institute of Standards and Technology) 2004 …


Automating The Extraction Of Domain-Specific Information From The Web-A Case Study For The Genealogical Domain, Troy L. Walker Nov 2004

Automating The Extraction Of Domain-Specific Information From The Web-A Case Study For The Genealogical Domain, Troy L. Walker

Theses and Dissertations

Current ways of finding genealogical information within the millions of pages on the Web are inadequate. In an effort to help genealogical researchers find desired information more quickly, we have developed GeneTIQS, a Genealogy Target-based Information Query System. GeneTIQS builds on ontology-based methods of data extraction to allow database-style queries on the Web. This thesis makes two main contributions to GeneTIQS. (1) It builds a framework to do generic ontology-based data extraction. (2) It develops a hybrid record separator based on Vector Space Modeling that uses both formatting clues and data clues to split pages into component records. The record …


Does The Halting Necessary For Hardware Trace Collection Inordinately Perturb The Results?, Myles G. Watson Nov 2004

Does The Halting Necessary For Hardware Trace Collection Inordinately Perturb The Results?, Myles G. Watson

Theses and Dissertations

Processor address traces are invaluable for characterizing workloads and testing proposed memory hierarchies. Long traces are needed to exercise modern cache designs and produce meaningful results, but are difficult to collect with hardware monitors because microprocessors access memory too frequently for disks or other large storage to keep up. The small, fast buffers of the monitors fill quickly; in order to obtain long contiguous traces, the processor must be stopped while the buffer is emptied. This halting may perturb the traces collected, but this cannot be measured directly, since long uninterrupted traces cannot be collected. We make the case that …


Real-Time Image Enhancement Using Texture Synthesis, Matthew J. Sorensen Nov 2004

Real-Time Image Enhancement Using Texture Synthesis, Matthew J. Sorensen

Theses and Dissertations

This thesis presents an approach to real-time image enhancement using texture synthesis. Traditional image enhancement techniques are typically time consuming, lack realistic detail, or do not scale well for large magnification factors.

Real-time Enhancement using Texture Synthesis (RETS) combines interpolation, classification, and patch-based texture synthesis to enhance low-resolution imagery, particularly aerial imagery. RETS uses as input a low-resolution source image and several high-resolution sample textures. The output of RETS is a high-resolution image with the structure of the source image, but with detail consistent with the high-resolution sample textures. We show that RETS can enhance large amounts of imagery in …


Geometric Acoustic Modeling Of The Lds Conference Center, Heather Smith Nov 2004

Geometric Acoustic Modeling Of The Lds Conference Center, Heather Smith

Theses and Dissertations

This thesis discusses the process of modeling a 21,000 seat fan-shaped auditorium using methods of geometric acoustics. Two commercial geometric acoustics software packages were used in the research: CATT-Acoustic™ 8.0 and EASE™ 4.1. The process first included creating preliminary models of the hall using published absorption coefficients for its surfaces and approximate scattering coefficients based on current best-known techniques. A detailed analysis determined the minimum numbers of rays needed in both packages to produce reliable results with these coefficient values. It was found that 100,000 rays were needed for CATT™ and 500,000 rays were needed for EASE™. Analysis was also …


Improved Signal Integrity In Ieee 1149.1 Boundary Scan Designs, Efren De Jesus Rangel Taboada Nov 2004

Improved Signal Integrity In Ieee 1149.1 Boundary Scan Designs, Efren De Jesus Rangel Taboada

Theses and Dissertations

This work is an analysis of solutions to problems derived from inherent timing and signal integrity issues in the use and application of the IEEE 1149.1 Standard at the board level in conjunction with its test system. Setup or hold times violations may occur in a boundary scan chain using IEEE 1149.1 compliant devices. A practical study of the TDI-TDO scan data path has been conducted to show where problems may arise in relationship to a particular board topology and test system. This work points to differences between passing and failing scan path tests for problem characterization. Serial data flow …


How Cellular Movement Determines The Collective Force Generated By The Dictyostelium Discoideum Slug, J. C. Dallon, H. G. Othmer Nov 2004

How Cellular Movement Determines The Collective Force Generated By The Dictyostelium Discoideum Slug, J. C. Dallon, H. G. Othmer

Faculty Publications

How the collective motion of cells in a biological tissue originates in the behavior of a collection of individuals, each of which responds to the chemical and mechanical signals it receives from neighbors, is still poorly understood. Here we study this question for a particular system, the slug stage of the cellular slime mold Dictyostelium discoideum. We investigate how cells in the interior of a migrating slug can effectively transmit stress to the substrate and thereby contribute to the overall motive force. Theoretical analysis suggests necessary conditions on the behavior of individual cells, and computational results shed light on experimental …


Computing The M = 1 Diocotron Frequency Via An Equilibrium Calculation In Non-Neutral Plasmas, Ross L. Spencer Oct 2004

Computing The M = 1 Diocotron Frequency Via An Equilibrium Calculation In Non-Neutral Plasmas, Ross L. Spencer

Faculty Publications

The m = 1 diocotron mode in non-neutral plasmas has long been thought of as a shifted equilibrium, and its frequency has been approximately calculated in this way by Fine and Driscoll [Phys. Plasmas 5, 601 (1998)]. This article shows that this idea can be coupled with a standard axisymmetric equilibrium calculation on a grid to calculate the frequency of this mode to very high precision including both finite-length and thermal effects, provided that the Debye length is small enough. As the Debye length begins to approach the plasma size not only does the shifted equilibrium calculation fail to predict …


Disk Based Model Checking, Tonglaga Bao Oct 2004

Disk Based Model Checking, Tonglaga Bao

Theses and Dissertations

Disk based model checking does not receive much attention in the model checking field becasue of its costly time overhead. In this thesis, we present a new disk based algorithm that can get close to or faster verification speed than a RAM based algorithm that has enough memory to complete its verification. This algorithm also outperforms Stern and Dill's original disk based algorithm. The algorithm partitions the state space to several files, and swaps files into and out of memory during verification. Compared with the RAM only algorithm, the new algoritm reduces hash table insertion time by reducing the cost …


Optical Properties And Application Of Uranium-Based Thin Films For The Extreme Ultraviolet And Soft X-Ray Region, Richard L. Sandberg, David D. Allred, Shannon Lunt, Marie K. Urry, R. Steven Turley Oct 2004

Optical Properties And Application Of Uranium-Based Thin Films For The Extreme Ultraviolet And Soft X-Ray Region, Richard L. Sandberg, David D. Allred, Shannon Lunt, Marie K. Urry, R. Steven Turley

Faculty Publications

Uranium oxide and uranium nitride thin films reflect significantly more than all previously known/standard reflectors (e.g., nickel, gold, and iridium) for most of the 4-10 nm range at low angles of incidence. This work includes measurements of the EUV/soft x-ray (2-20 nm) reflectance of uranium-based thin films (~20 nm thick) and extraction of their optical constants (d and ?). We report the reflectances at 5, 10, and 15 degrees grazing incidence of air-oxidized sputtered uranium, reactively sputtered (O2) uranium oxide, and reactively sputtered (N2) uranium nitride thin films measured at Beamline 6.3.2 at the Advanced Light Source (ALS) at Lawrence …


Vision-Based Human Directed Robot Guidance, Richard B. Arthur Oct 2004

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 Oct 2004

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 Sep 2004

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 Sep 2004

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 Sep 2004

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 Sep 2004

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 Aug 2004

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 Aug 2004

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 Aug 2004

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.


Instructing Teachers Of Children With Disabilities Within The Church Of Jesus Christ Of Latter-Day Saints, Katie E. Sampson Aug 2004

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.


T-Spline Simplification And Local Refinement, David L. Cardon, G. Thomas Finnigan, Nicholas S. North, Thomas W. Sederberg, Jianmin Zheng, Tom Lyche Aug 2004

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.


Capillary Liquid Chromatography Using Micro Size Particles, Yanqiao Xiang Jul 2004

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 Jul 2004

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 …