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Three Enabling Technologies For Vision-Based, Forest-Fire Perimeter Surveillance Using Multiple Unmanned Aerial Systems, Ryan S. Holt Jun 2007

Three Enabling Technologies For Vision-Based, Forest-Fire Perimeter Surveillance Using Multiple Unmanned Aerial Systems, Ryan S. Holt

Theses and Dissertations

The ability to gather and process information regarding the condition of forest fires is essential to cost-effective, safe, and efficient fire fighting. Advances in sensory and autopilot technology have made miniature unmanned aerial systems (UASs) an important tool in the acquisition of information. This thesis addresses some of the challenges faced when employing UASs for forest-fire perimeter surveillance; namely, perimeter tracking, cooperative perimeter surveillance, and path planning. Solutions to the first two issues are presented and a method for understanding path planning within the context of a forest-fire environment is demonstrated. Both simulation and hardware results are provided for each …

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Conceptual Xml For Systems Analysis, Reema Al-Kamha Jun 2007

Conceptual Xml For Systems Analysis, Reema Al-Kamha

Theses and Dissertations

Because XML has become a new standard for data representation, there is a need for a simple conceptual model that works well with XML-based development. In this research we present a conceptual model for XML, called C-XML, which meets this new need of systems analysts who store their data using XML. We describe our implementation of an automatic conversion from XML Schema to C-XML that preserves information and constraints. With this conversion, we can view an XML Schema instance graphically at a higher level of abstraction. We also describe our implementation of an automatic conversion from C-XML to XML Schema. …

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Intelligent Rotoscoping: A Semi-Automated Interactive Boundary Tracking Approach To Video Segmentation, Seth R. Holladay Jun 2007

Intelligent Rotoscoping: A Semi-Automated Interactive Boundary Tracking Approach To Video Segmentation, Seth R. Holladay

Theses and Dissertations

Video segmentation is an application of computer vision aimed at automating the extraction of an object from a series of video frames. However, it is a difficult problem, especially to compute at real-time, interactive rates. Although general application to video is difficult because of the wide range of image scenarios, user interaction can help to reduce the problem space and speed up the computation. This thesis presents a fast object-tracking tool that selects an object from a series of frames based on minimal user input. Our Intelligent Rotoscoping tool aims for increased speed and accuracy over other video segmentation tools, …

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Finding Termination And Time Improvement In Predicate Abstraction With Under-Approximation And Abstract Matching, Dritan Kudra Jun 2007

Finding Termination And Time Improvement In Predicate Abstraction With Under-Approximation And Abstract Matching, Dritan Kudra

Theses and Dissertations

The focus of current formal verification methods is mitigating the state explosion problem. One of these formal methods is predicate abstraction, which reduces concrete states of a system to bitvectors of true/false valuations of a set of predicates. Predicate abstraction comes in two flavors, over-approximation and under-approximation. A drawback of over-approximation is that it produces too many spurious errors for data-intensive applications. A more recent under-approximation technique which does not produce spurious errors, does abstract matching on concrete states (AMCS). AMCS adds behaviors to an abstract system by augmenting the set of initial predicates, making use of a theorem prover. …

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Cognitive And Behavioral Model Ensembles For Autonomous Virtual Characters, Jeffrey S. Whiting Jun 2007

Cognitive And Behavioral Model Ensembles For Autonomous Virtual Characters, Jeffrey S. Whiting

Theses and Dissertations

Cognitive and behavioral models have become popular methods to create autonomous self-animating characters. Creating these models presents the following challenges: (1) Creating a cognitive or behavioral model is a time intensive and complex process that must be done by an expert programmer (2) The models are created to solve a specific problem in a given environment and because of their specific nature cannot be easily reused. Combining existing models together would allow an animator, without the need of a programmer, to create new characters in less time and would be able to leverage each model's strengths to increase the character's …

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Therapists' Perceived Influence Of Language: Second Language Spanish Speaking Therapists With Native Spanish-Speaking Clients, Cameron D. Mount Jun 2007

Therapists' Perceived Influence Of Language: Second Language Spanish Speaking Therapists With Native Spanish-Speaking Clients, Cameron D. Mount

Theses and Dissertations

Experiences of the bilingual client in therapy have received attention in the literature but accounts of the experience of the bilingual therapist are strikingly sparse. The purpose of this study was to focus on the bilingual therapist's perception of the impact of language on the therapeutic process. To achieve this goal, the researcher interviewed therapists who speak Spanish as a second language and work with native Spanish-speaking clients. Data analysis was completed using ethnographic research methods, which resulted in the emergence of three themes. The first theme included therapists' perceived obstacles to second-language therapy. Each of the participants in the …

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Computationally Efficient Modeling Of Transient Radiation In A Purely Scattering Foam Layer, Rudolph Scott Larson Jun 2007

Computationally Efficient Modeling Of Transient Radiation In A Purely Scattering Foam Layer, Rudolph Scott Larson

Theses and Dissertations

An efficient solution method for evaluating radiative transport in a foam layer is a valuable tool for predicting the properties of the layer. Two different solution methods have been investigated. First, a reverse Monte Carlo (RMC) simulation has been developed. In the RMC simulation photon bundles are traced backwards from a detector to the source where they were emitted. The RMC method takes advantage of time reflection symmetry, allowing the photons to be traced backwards in the same manner they are tracked in a standard forward Monte Carlo scheme. Second, a reduced order model based on the singular value decomposition …

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Earth Science Mini-Lessons: A Service-Learning Strategy For Improving Attitudes Toward Science Of Preservice Elementary Teachers, K. Thompson, B. R. Bickmore, Charles R. Graham, S. C. Yanchar Jun 2007

Earth Science Mini-Lessons: A Service-Learning Strategy For Improving Attitudes Toward Science Of Preservice Elementary Teachers, K. Thompson, B. R. Bickmore, Charles R. Graham, S. C. Yanchar

Faculty Publications

Science instruction in elementary school classrooms is frequently lacking in the United States. One factor that impacts the amount and quality of science instruction is teacher attitudes toward science. The Earth Science Mini-Lesson Project is a strategic program created to help improve preservice elementary school teachers' attitudes toward science in a one-semester college class. Students participating in this project create earth science mini-lessons on topics taken from the Utah Core Curriculum Standards and teach them to elementary students at a local Title I grade school. Attitude survey results from both semesters showed that this service-learning outreach program positively affected students' …

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Carlo Cattaneo: The Religiosity Of A Relunctant Revolutionary, Carolyn Bennett Ugolini Jun 2007

Carlo Cattaneo: The Religiosity Of A Relunctant Revolutionary, Carolyn Bennett Ugolini

Theses and Dissertations

Carlo Cattaneo (1801-1869) would have been a remarkable man in any time period. He was interested in everything, and as a man of ideas was involved in the astonishing technological and stimulating political events of the nineteenth century. He encouraged the building of railways as a way to unite the Italian peninsula, and he was involved in connecting Italy to the rest of Europe through the St. Gothard Tunnel. An innovator of gas lighting in his native Milan, the great Lombard thinker was a prolific writer, and kept prodigious notes and copies of his correspondence. His economic and scientific involvement …

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Mapping Middle Paleozoic Erosional And Karstic Patterns With 3-D Seismic Attributes And Well Data In The Arkoma Basin, Oklahoma, Alonzo R. Brinkerhoff Jun 2007

Mapping Middle Paleozoic Erosional And Karstic Patterns With 3-D Seismic Attributes And Well Data In The Arkoma Basin, Oklahoma, Alonzo R. Brinkerhoff

Theses and Dissertations

Newly available industry well data and seismic attribute analysis reveal that late Ordovician-early Devonian Hunton Group strata are more widespread (i.e., not removed by mid-Devonian erosion) in the central and southern portions of the Arkoma Basin in eastern Oklahoma than previously thought. This study demonstrates the value of applying seismic attribute analysis to problems of quantifying and mapping stratigraphic features caused by erosions and/or karstification. Well and seismic isochron data in the Red Oak petroleum field for the Viola-Woodford interval (the units that lie stratigraphically beneath and above, respectively, the Huton Group) show isolated ~40-m thick lenses of Hunton rocks, …

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Vision-Based Control And Flight Optimization Of A Rotorcraft Uav, David Christian Hubbard Jun 2007

Vision-Based Control And Flight Optimization Of A Rotorcraft Uav, David Christian Hubbard

Theses and Dissertations

A Rotorcraft UAV provides an ideal experimental platform for vision-based navigation. This thesis describes the flight tests of the US Army PALACE pro ject, which implements Moravec's pseudo-normalized correlation tracking algorithm. The tracker uses the movement of the landing site in the camera, a laser range, and the aircraft attitude from an IMU to estimate the relative motion of the UAV. The position estimate functions as a GPS equivalent to enable the rotorcraft to maneuver without the aid of GPS. Flight tests were performed with obstacles and over concrete, asphalt, and grass in daylight conditions with a safe landing area …

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No. 142 Journal Of East Asian Libraries, Journal Of East Asian Libraries Jun 2007

No. 142 Journal Of East Asian Libraries, Journal Of East Asian Libraries

Journal of East Asian Libraries

No abstract provided.

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With Memories Of Karl Lo: A Report On The 9Th International Conference On Asian Digital Libraries, Maureen H. Donovan Jun 2007

With Memories Of Karl Lo: A Report On The 9Th International Conference On Asian Digital Libraries, Maureen H. Donovan

Journal of East Asian Libraries

No abstract provided.

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Patterns Of User Activity In The Blackboard Course Management System Across All Courses In The 2004-2005 Academic Year At Brigham Young University, Michael E. Griffiths Jun 2007

Patterns Of User Activity In The Blackboard Course Management System Across All Courses In The 2004-2005 Academic Year At Brigham Young University, Michael E. Griffiths

Theses and Dissertations

The following report discusses the use of the Blackboard Course Management in terms of overall patterns of activity as recorded in the Blackboard activity database across the whole campus of Brigham Young University during the 2004-2005 academic year. The report contains a set of data represented by tables and graphs that summarize activity, or clicks, in the Blackboard system performed by students, professors, and assistants. The clicks are summarized according to a number of different categories and criteria and analyzed to show interesting patterns of activity. The report is designed to show a general campus wide summary of Blackboard activity …

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Active Learning For Part-Of-Speech Tagging: Accelerating Corpus Annotation, George Busby, Marc Carmen, James Carroll, Robbie Haertel, Deryle W. Lonsdale, Peter Mcclanahan, Eric K. Ringger, Kevin Seppi Jun 2007

Active Learning For Part-Of-Speech Tagging: Accelerating Corpus Annotation, George Busby, Marc Carmen, James Carroll, Robbie Haertel, Deryle W. Lonsdale, Peter Mcclanahan, Eric K. Ringger, Kevin Seppi

Faculty Publications

In the construction of a part-of-speech annotated corpus, we are constrained by a fixed budget. A fully annotated corpus is required, but we can afford to label only a subset. We train a Maximum Entropy Markov Model tagger from a labeled subset and automatically tag the remainder. This paper addresses the question of where to focus our manual tagging efforts in order to deliver an annotation of highest quality. In this context, we find that active learning is always helpful. We focus on Query by Uncertainty (QBU) and Query by Committee (QBC) and report on experiments with several baselines and …

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Temporally Correlated Dirichlet Processes In Pollution Receptor Modeling, Matthew J. Heaton May 2007

Temporally Correlated Dirichlet Processes In Pollution Receptor Modeling, Matthew J. Heaton

Theses and Dissertations

Understanding the effect of human-induced pollution on the environment is an important precursor to promoting public health and environmental stability. One aspect of understanding pollution is understanding pollution sources. Various methods have been used and developed to understand pollution sources and the amount of pollution those sources emit. Multivariate receptor modeling seeks to estimate pollution source profiles and pollution emissions from concentrations of pollutants such as particulate matter (PM) in the air. Previous approaches to multivariate receptor modeling make the following two key assumptions: (1) PM measurements are independent and (2) source profiles are constant through time. Notwithstanding these assumptions, …

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What Are Some Of The Common Traits In The Thought Processes Of Undergraduate Students Capable Of Creating Proof?, Karen Malina Duff May 2007

What Are Some Of The Common Traits In The Thought Processes Of Undergraduate Students Capable Of Creating Proof?, Karen Malina Duff

Theses and Dissertations

Mathematical proof is an important topic in mathematics education research. Many researchers have addressed various aspects of proof. One aspect that has not been addressed is what common traits are shared by those who are successful at creating proof. This research investigates the common traits in the thought processes of undergraduate students who are considered successful by their professors at creating mathematical proof. A successful proof is defined as a proof that successfully accomplishes at least one of DeVilliers (2003) six roles of proof and demonstrates adequate mathematical content, knowledge, deduction and logical reasoning abilities. This will typically be present …

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On Connections Between Univalent Harmonic Functions, Symmetry Groups, And Minimal Surfaces, Stephen M. Taylor May 2007

On Connections Between Univalent Harmonic Functions, Symmetry Groups, And Minimal Surfaces, Stephen M. Taylor

Theses and Dissertations

We survey standard topics in elementary differential geometry and complex analysis to build up the necessary theory for studying applications of univalent harmonic function theory to minimal surfaces. We then proceed to consider convex combination harmonic mappings of the form f=sf_1+(1-s) f_2 and give conditions on when f lifts to a one-parameter family of minimal surfaces via the Weierstrauss-Enneper representation formula. Finally, we demand two minimal surfaces M and M' be locally isometric, formulate a system of partial differential equations modeling this constraint, and calculate their symmetry group. The group elements generate transformations that when applied to a prescribed harmonic …

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Asymmetric Dihydroxylation And Aziridination Of Allenes And Related Chemistry, Renmao Liu May 2007

Asymmetric Dihydroxylation And Aziridination Of Allenes And Related Chemistry, Renmao Liu

Theses and Dissertations

A novel method for asymmetric synthesis of α-hydroxy ketone with excellent regio- and stereoselectivity has been established by the systematic investigation of asymmetric dihydroxylation of allenes. The efficiency of kinetic resolution of racemic allenes was also investigated by using the AD reaction on both 1,3-disubstituted and trisubstituted allenes. Steric effects, electronic effects and allene substitution are also discussed. Aziridines were formed by copper-catalyzed intramolecular nitrene addition to alkenes. The carbamate group was used as the tether between the alkene and the nitrene. Subsequent nucleophilic attack of the aziridine was accomplished using RSH, R2NH, N3-,or ROH as the nucleophile. This addition …

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Investigation Of The Iron Oxidation Kinetics In Mantua Reservoir, Scott H. Lathen May 2007

Investigation Of The Iron Oxidation Kinetics In Mantua Reservoir, Scott H. Lathen

Theses and Dissertations

Irrigation of the municipal cemetery in Brigham City, Utah resulted in stained headstones in 2001 and 2002. The water used in the irrigation came from Mantua reservoir, a medium sized impoundment situated near the mouth of Box Elder Canyon. In order for Brigham City to establish a city wide secondary pressurized irrigation system using water from Mantua reservoir, the cause and the source of staining problem must be determined. Previous research (Wallace 2006) determined that the source of the staining was the reduction of iron found in Mantua Reservoir sediments that occurred when seasonal variations in the reservoir caused anaerobic …

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Towards Early State Disease Detection In Microdevices: Fabrication And Testing Of Micro Total Analysis Systems For Bioanalytical Applications, Tao Pan May 2007

Towards Early State Disease Detection In Microdevices: Fabrication And Testing Of Micro Total Analysis Systems For Bioanalytical Applications, Tao Pan

Theses and Dissertations

The past few years have seen a rapid expansion in interest in the characterization of the entire complement of proteins, or proteome. Micro total analysis systems (μTAS) are an emerging promising method, offering rapid, sensitive and low sample consumption separations. I have demonstrated microchip capillary electrophoresis (CE) devices made of CaF2. New methods have been developed for micromachining enclosed capillaries in CaF2. CE analysis of fluorescently labeled amino acids was used to illustrate bioanalytical applications of these microdevices. Initial on-chip infrared spectroscopy results for qualitative analyte identification were achieved in microfluidic CaF2 channels. I have also shown the evaluation of …

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Origin And Tectonic Evolution Of Gondwana Sequence Units Accreted To The Banda Arc: A Structural Transect Through Central East Timor, Elizabeth Anick Zobell May 2007

Origin And Tectonic Evolution Of Gondwana Sequence Units Accreted To The Banda Arc: A Structural Transect Through Central East Timor, Elizabeth Anick Zobell

Theses and Dissertations

Petrographic and age analysis of sandstones, detailed structural analysis and gravity modeling were conducted to investigate the origin of the Gondwana Sequence in the Timor Region, and to better constrain the tectonic evolution of the active Banda Arc. Our field studies and U/Pb zircon age analysis helped assign most units to either Asian or Australian affinity. Detrital zircon from uplifted Banda forearc units (Asian affinity) have U/Pb ages as young as 80 Ma (Standley and Harris, in press). In contrast, analysis of detrital zircon from Gondwana Sequence sandstones accreted to the Banda Arc from Savu to East Timor are no …

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Multi-Stable Compliant Rolling-Contact Elements, Peter Andrew Halverson May 2007

Multi-Stable Compliant Rolling-Contact Elements, Peter Andrew Halverson

Theses and Dissertations

The purpose of this research is the development of design concepts and models of large-angle, compliant, multistable, revolute joints. This research presents evidence of the capability of these models and concepts by presenting a case study in which the miniaturization of revolute joints are examined. Previous attempts at multistable revolute joints can be categorized into two categories: compliant and non-compliant mechanisms. Non-compliant multistable revolute joints are typified by a combination of pin-in-slot joints, springs, and detents. Due to factors inherit in design, noncompliant joints often succumb to friction, wear, and undesirable motion, that leads to a decline in performance. Compliant …

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To Repair Or Not To Repair: Helping Ad Hoc Routing Protocols To Distinguish Mobility From Congestion, Qiuyi Duan, Roger Pack, Manoj Pandey, Lei Wang, Daniel Zappala May 2007

To Repair Or Not To Repair: Helping Ad Hoc Routing Protocols To Distinguish Mobility From Congestion, Qiuyi Duan, Roger Pack, Manoj Pandey, Lei Wang, Daniel Zappala

Faculty Publications

In this paper we consider the problem of distinguishing whether frame loss at the MAC layer has occurred due to mobility or congestion. Most ad hoc routing protocols make the faulty assumption that all frame loss means the destination node has moved, resulting in significant overhead as they initiate the repair of routes that have not been broken. We design a mobility detection algorithm, MDA, that properly detects the cause of a lost frame, then coordinates with the routing protocol so that it reacts properly. This approach dramatically reduces routing protocol overhead and significantly increases application throughput. We use a …

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Anomalous Magnetic Field Dependence Of The T1 Spin Lifetime In A Lightly Doped Gaas Sample, John S. Colton, M. E. Heeb, P. Schroeder, A. Stokes, L. R. Wienkes, A. S. Bracker May 2007

Anomalous Magnetic Field Dependence Of The T1 Spin Lifetime In A Lightly Doped Gaas Sample, John S. Colton, M. E. Heeb, P. Schroeder, A. Stokes, L. R. Wienkes, A. S. Bracker

Faculty Publications

The T1 spin lifetime of a lightly doped n-type GaAs sample has been measured via time-resolved polarization spectroscopy under a number of temperature and magnetic field conditions. Lifetimes up to 19 μs have been measured. The magnetic field dependence of T1 shows a nonmonotonic behavior, where the spin lifetime first increases, then decreases, then increases again with field. The initial increase in T1 is understood to be due to correlation between electrons localized on donors. The decrease in T1 is likely due to phonon-related spin-orbit relaxation. The final increase in T1 with B indicates a suppression of the spin-orbit relaxation …

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Experimental Characterization Of The Outdoor Mimo Wireless Channel Temporal Variation, Michael A. Jensen, Karl F. Warnick, Jon W. Wallace, Ajay Gummalla, Harry B. Lee May 2007

Experimental Characterization Of The Outdoor Mimo Wireless Channel Temporal Variation, Michael A. Jensen, Karl F. Warnick, Jon W. Wallace, Ajay Gummalla, Harry B. Lee

Faculty Publications

Time-variant multiple-input multiple-output (MIMO) channels are measured in an outdoor campus environment at 2.45 GHz with directional patch arrays and omnidirectional monopole arrays. A number of useful metrics are proposed for quantifying time variation in MIMO channels: eigenvalue level crossing rate, eigenvector angular deviation, and capacity loss for delayed transmit and receive channel state information (CSI). Measurements in four different environments confirm the strong correlation between angular spread of multipath and MIMO channel time variability. The rate of time variation is also strongly influenced by the type of array, indicating that directional elements may be advantageous for highly mobile environments. …

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The Relationship Between Antenna Loss And Superdirectivity In Mimo Systems, Michael A. Jensen, Nicolas W. Bikhazi May 2007

The Relationship Between Antenna Loss And Superdirectivity In Mimo Systems, Michael A. Jensen, Nicolas W. Bikhazi

Faculty Publications

Multiple-input multiple-output (MIMO) communication systems can theoretically use array superdirectivity to optimally exploit the propagation channel. This superdirectivity leads to very large capacity bounds, particularly when the antennas are closely spaced. However, because superdirective behavior is difficult to achieve in practice, new capacity bounds have been formulated for the case where the level of array superdirectivity is constrained. Existing capacity analyses limit the superdirectivity in a suboptimal way. In this paper, the impact of superdirectivity in the capacity solution is limited by introducing finite ohmic loss in the transmit and receive antenna elements. Computational results reveal that even a small …

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Probabilistic Searching Using A Small Unmanned Aerial Vehicle, Steven R. Hansen, Timothy W. Mclain, Michael A. Goodrich May 2007

Probabilistic Searching Using A Small Unmanned Aerial Vehicle, Steven R. Hansen, Timothy W. Mclain, Michael A. Goodrich

Faculty Publications

Ground breaking concepts in optimal search theory were developed during World War II by the U.S. Navy. These concepts use an assumed detection model to calculate a detection probability rate and an optimal search allocation. Although this theory is useful in determining when and where search effort should be applied, it offers little guidance for the planning of search paths. This paper explains how search theory can be applied to path planning for an SUAV with a fixed CCD camera. Three search strategies are developed: greedy search, contour search, and composite search. In addition, the concepts of search efficiency and …

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Manifold Sculpting, Michael S. Gashler Apr 2007

Manifold Sculpting, Michael S. Gashler

Theses and Dissertations

Manifold learning algorithms have been shown to be useful for many applications of numerical analysis. Unfortunately, existing algorithms often produce noisy results, do not scale well, and are unable to benefit from prior knowledge about the expected results. We propose a new algorithm that iteratively discovers manifolds by preserving the local structure among neighboring data points while scaling down the values in unwanted dimensions. This algorithm produces less noisy results than existing algorithms, and it scales better when the number of data points is much larger than the number of dimensions. Additionally, this algorithm is able to benefit from existing …

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Coupling Down Converted Light Into Single Mode Fibers, David A. Niemi Apr 2007

Coupling Down Converted Light Into Single Mode Fibers, David A. Niemi

Theses and Dissertations

We investigate the influence of the pump and collection mode parameters on the collection efficiency of Type I down converted photons into single mode fibers. For best single and coincidence counting rates, we find that the mode sizes should be close to the same size and that the mode waists should be located near the down-conversion crystal. Larger collection waists give higher collection efficiencies, but lower singles counts.

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