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Two-Photon Photoionization Of The Ca 4s3d^1d2 Level In An Optical Dipole Trap, E. A. Cummings, J. E. Daily, Dallin S. Durfee, Scott D. Bergeson, R. Gommers Apr 2005

Two-Photon Photoionization Of The Ca 4s3d^1d2 Level In An Optical Dipole Trap, E. A. Cummings, J. E. Daily, Dallin S. Durfee, Scott D. Bergeson, R. Gommers

Faculty Publications

We report an optical dipole trap for calcium. The trap is created by focusing a 488-nm argon-ion laser beam into a calcium magneto-optical trap. The argon-ion laser photoionizes atoms in the trap because of a near-resonance with the 4s4f 1^F3 level. By measuring the dipole-trap decay rate as a function of argon-ion laser intensity, we determine the 1^F3 photoionization cross section at our wavelength to be approximately 230 Mb.


January: Search Based On Social Insect Behavior, Peter C. Lamborn Apr 2005

January: Search Based On Social Insect Behavior, Peter C. Lamborn

Theses and Dissertations

January is a group of interacting stateless model checkers. Each agent functions on a processor located on a super computer or a network of workstations (NOW). The agent's search pattern is a semi-random walk based on the behavior of the grey field slug (Agriolimax reticulatus), the house fly (Musca domestica), and the black ant (Lassius niger). The agents communicate to lessen the amount of duplicate work being done. Every algorithm has a memory threshold above which they search efficiently. This threshold varies not only by model but also by algorithm. Janaury's threshold is lower than the thresholds of other algorithms …


Improving Routing Security Using A Decentralized Public Key Distribution Algorithm, Jeremy C. Goold Apr 2005

Improving Routing Security Using A Decentralized Public Key Distribution Algorithm, Jeremy C. Goold

Theses and Dissertations

Today's society has developed a reliance on networking infrastructures. Health, financial, and many other institutions deploy mission critical and even life critical applications on local networks and the global Internet. The security of this infrastructure has been called into question over the last decade. In particular, the protocols directing traffic through the network have been found to be vulnerable. One such protocol is the Open Shortest Path First (OSPF) protocol. This thesis proposes a security extension to OSPF containing a decentralized certificate authentication scheme (DecentCA) that eliminates the single point of failure/attack present in current OSPF security extensions. An analysis …


A Voice For Modernism In Elsa Bienenfeld`S Music Reviews, Draper Kelsey Apr 2005

A Voice For Modernism In Elsa Bienenfeld`S Music Reviews, Draper Kelsey

Prose Nonfiction

No abstract provided.


Prioritized Multiplicative Schwarz Procedures For Solving Linear Systems, Nathaniel Powell, Kevin Seppi, Quinn O. Snell, David Wingate Apr 2005

Prioritized Multiplicative Schwarz Procedures For Solving Linear Systems, Nathaniel Powell, Kevin Seppi, Quinn O. Snell, David Wingate

Faculty Publications

We describe a new algorithm designed to quickly and robustly solve general linear problems of the form Ax = b. We describe both serial and parallel versions of the algorithm, which can be considered a prioritized version of an Alternating Multiplicative Schwarz procedure. We also adopt a general view of alternating Multiplicative Schwarz procedures which motivates their use on arbitrary problems (even which may not have arisen from problems that are naturally decomposable) by demonstrating that, even in a serial context, algorithms should use many, many partitions to accelerate convergence; having such an over-partitioned system also allows easy parallelization of …


A Voice For Modernism In Elsa Bienenfeld's Music Reviews, Kelsey Draper Apr 2005

A Voice For Modernism In Elsa Bienenfeld's Music Reviews, Kelsey Draper

Undergraduate Honors Theses

This thesis discusses Elsa Bienenfeld’s role as a modern music critic and cultural journalist and shows how she defended modernism by encouraging her Viennese readers to embrace it. The purpose is not to create a mere biographical sketch, but to demonstrate how Bienenfeld shaped and influenced the public’s perceptions of the budding modern music movement in Vienna. Chapter 1 introduces the problem of modern music and provides the historical context for Elsa Bienenfeld’s life. Chapter 2 introduces modermism as a movement in the city and reviews the development of music out of the classical and romantic periods into modernism. Chapter …


Sound-Quality Analysis Of Sewing Machines (A), James Chatterley, Andrew Boone, Jonathan T. Blotter, Scott D. Sommerfeldt Apr 2005

Sound-Quality Analysis Of Sewing Machines (A), James Chatterley, Andrew Boone, Jonathan T. Blotter, Scott D. Sommerfeldt

Faculty Publications

Sound quality analysis procedure and results for six sewing machines ranging from entry level to professional grade will be presented. The procedure consisted of jury-based listening tests and quantification of sound quality using standard metrics. The procedures and analysis of the jury testing will be presented and discussed. The correlation between the quantitative metrics and the qualitative jury results will be presented. Sound localization scans, using near field acoustic holography techniques with accompanying results, performed in order to determine machine sound hot spots and possible sources for undesired sounds, will also be presented. Proposed modifications to machine structure in order …


Geology Of The Tierras Blancas Area In The Southeastern Acambay Graben, Central Mexico, Lonnie T. Mercer Mar 2005

Geology Of The Tierras Blancas Area In The Southeastern Acambay Graben, Central Mexico, Lonnie T. Mercer

Theses and Dissertations

Pliocene-Pleistocene sediments in the southeastern Acambay graben, central Mexico have yielded mammal fossils, including Equus simplicidens, cf. Rhynchotherium, ?Camelops, Mammuthus sp., Bison sp., and Antilocapra sp. The fossiliferous sediments include a period of lacustrine sedimentation in the late Pliocene-early Pleistocene that interrupted fluvial and alluvial sedimentation during the early Pliocene and Pleistocene. The sediments deposited in this late Pliocene paleolake record a history of lake level fluctuations, shown by lithologic variations in lacustrine sediments and abundance of vertebrate burrows. Volcanic and tectonic events in the Acambay graben were the major controls on sedimentation during Pliocene-Pleistocene time. …


Electrothermomechanical Modeling Of A Surface-Micromachined Linear Displacement Microactuator, Christian D. Lott Mar 2005

Electrothermomechanical Modeling Of A Surface-Micromachined Linear Displacement Microactuator, Christian D. Lott

Theses and Dissertations

The electrothermomechanical characteristics of an electrically-heated polycrystallinesilicon microactuator are explored. Using finite-difference techniques, an electrothermal model based on the balance of heat dissipation and heat losses is developed. For accurate simulation, the relevant temperature dependent properties from the microactuator material are included in the model. The electrothermal model accurately predicts the steady-state power required to hold position, and the energy consumed during the thermal transient. Thermomechanical models use the predictions of temperature from the electrothermal solution to calculate displacement and force from pseudo-rigid-body approximations and commercial finite-element code. The models are verified by comparing experimental data to simulation results of …


Alterations In Uterine And Placental Sodium Pump Abundance May Contribute To The Onset Of Mouse Labor, Carlos Jacob Vance Mar 2005

Alterations In Uterine And Placental Sodium Pump Abundance May Contribute To The Onset Of Mouse Labor, Carlos Jacob Vance

Theses and Dissertations

Objective: Reductions in sodium pump (SP) abundance can give rise to increases in contractile force in uterine and vascular smooth muscle as well as an increased secretion in secretory cells, including potentially those of the placenta. To determine whether the mouse might serve as a model for human pregnancy in terms of the SP and to determine whether changes in SP abundance anticipate or follow labor, we studied pregnant mice over the final trimester of their pregnancy.

Study Design: C57Bl6 dams (n=46) were bred and studied during their pregnancy. Animals (n=4) were sacrificed at specific gestational time points. Other mice …


Ion Transmission In The First Vacuum Stage Of An Inductively Coupled Plasma Mass Spectrometer, Jeffrey Harris Macedone Mar 2005

Ion Transmission In The First Vacuum Stage Of An Inductively Coupled Plasma Mass Spectrometer, Jeffrey Harris Macedone

Theses and Dissertations

The inductively coupled plasma mass spectrometer (ICP-MS) is the instrument of choice for trace and ultra-trace elemental analysis. However, the ICP-MS suffers from matrix effects. Matrix effects occur when instrument response varies as the composition of the sample matrix is changed. Matrix effects, or non-spectroscopic interferences, limit the accuracy of routine analysis. Identification of the sources of matrix effects provide a basis for reducing or eliminating them. As inaccuracies in the ICP-MS are more severe than those in the ICP atomic emission spectrometer, the problem may be due, at least in part, to the vacuum interface used to couple the …


Sequence Stratigraphy Of The Bridal Veil Falls Limestone, Carboniferous, Lower Oquirrh Group, On Cascade Mountain, Utah: A Standard Morrowan Cyclostratigraphy For The Oquirrh Basin, David Joseph Shoore Mar 2005

Sequence Stratigraphy Of The Bridal Veil Falls Limestone, Carboniferous, Lower Oquirrh Group, On Cascade Mountain, Utah: A Standard Morrowan Cyclostratigraphy For The Oquirrh Basin, David Joseph Shoore

Theses and Dissertations

The Bridal Veil Falls Limestone (lowest 400 meters of the Permo-Carboniferous Oquirrh Group) is well exposed on the flanks of Cascade Mountain (Wasatch Front and adjacent mountain ranges) near Provo, Utah. Because of its excellent exposure and location in the heart of the Oquirrh depocenter, this area was selected to develop a sequence stratigraphic framework for Morrowan rocks that may be applied throughout the Oquirrh basin (NW Utah and southern Idaho) as well as the adjacent Ely and Bird Springs troughs. Eleven partial to complete sections of the Bridal Veil Falls Limestone were measured along the west and north flanks …


Equalization Techniques For Multipath Mitigation In Aeronautical Telemetry, Vladimir Ignacio Paje Mar 2005

Equalization Techniques For Multipath Mitigation In Aeronautical Telemetry, Vladimir Ignacio Paje

Theses and Dissertations

This thesis describes the application of adaptive equalization based on the constant modulus algorithm (CMA) and the decision-feedback minimum mean squared error (DF-MMSE) concept to the two compatible offset QPSK waveforms (FQPSK and SOQPSK-TG) that constitute the ARTM Tier-1 waveforms. An adaptive version of the DF-MMSE equalizer is developed and applied to this application. In the presence of frequency selective multipath interference typically encountered in aeronautical telemetry, both equalization techniques are shown to provide reliable performance for FQPSK and SOQPSK-TG. The performance of both waveforms with the DF-MMSE equalizer is slightly better than that using the CMA equalizer. Implementation trade-offs …


Structure From Motion Using Optical Flow Probability Distributions, Paul Clark Merrell Mar 2005

Structure From Motion Using Optical Flow Probability Distributions, Paul Clark Merrell

Theses and Dissertations

Several novel structure from motion algorithms are presented that are designed to more effectively manage the problem of noise. In many practical applications, structure from motion algorithms fail to work properly because of the noise in the optical flow values. Most structure from motion algorithms implicitly assume that the noise is identically distributed and that the noise is white. Both assumptions are false. Some points can be track more easily than others and some points can be tracked more easily in a particular direction. The accuracy of each optical flow value can be quantified using an optical flow probability distribution. …


The Effects Of Fault-Induced Stress Anisotropy On Fracturing, Folding And Sill Emplacement: Insights From The Bowie Coal Mines, Southern Piceance Basin, Western Colorado., Eric Dean Robeck Mar 2005

The Effects Of Fault-Induced Stress Anisotropy On Fracturing, Folding And Sill Emplacement: Insights From The Bowie Coal Mines, Southern Piceance Basin, Western Colorado., Eric Dean Robeck

Theses and Dissertations

The recognition of fault-perturbed stress fields is an important tool in areas of mineral or hydrocarbon exploration. The Bowie underground coal mines of western Colorado expose a reverse-reactivated growth fault that perturbed the stress field during cleat (fracture) formation, rotating cleat orientations up to 500 m on both sides of the fault. Two unusual fracture types are found only in coal adjacent to the fault: (1) concentric cleats, highly curved fractures that form blocks resembling balls or eggs and (2) horsetail cleats, striated surfaces that superficially resemble shattercones and result from shear failure in coal. Numerical models created with the …


The Relationships Among Literacy, Church Activity And Religious Orientation: A Study Of Adult Members Of The Lds Church In Utah County, Bruce R. Brewer Mar 2005

The Relationships Among Literacy, Church Activity And Religious Orientation: A Study Of Adult Members Of The Lds Church In Utah County, Bruce R. Brewer

Theses and Dissertations

The study assessed the interplay among literacy, church activity, and religious orientation and examined the extent to which literacy predicts church activity in the presence of private religious behavior. One hundred fifty-seven subjects were administered measures of intrinsic religiousness, extrinsic religiousness, literacy levels and measures of church activity. The findings from this study suggest that literacy is related to activity, but in a way that is more complex than many investigators have considered. The results of the multiple regression analysis helped clarify the ability of literacy to predict church activity in the presence of religious orientation. Results further indicated that …


Developing A Design Space Model Using A Multidisciplinary Design Optimization Schema In A Product Lifecycle Management System To Capture Knowledge For Reuse, Nathaniel Luke Fife Mar 2005

Developing A Design Space Model Using A Multidisciplinary Design Optimization Schema In A Product Lifecycle Management System To Capture Knowledge For Reuse, Nathaniel Luke Fife

Theses and Dissertations

Parametric strategies for design automation and optimization can have a big impact on engineering design. When parametric tasks and optimization frameworks and methods are combined, theses strategies can be used to make up what is known as a multidisciplinary design optimization (MDO) schema. Knowledge of a design space can be modeled by using a MDO schema to represent the design process. However, current MDO frameworks used to create this schema lack the scope to capture enterprise wide knowledge for reuse and collaboration. Concurrent with the development of MDO, many companies are moving toward increased use of product lifecycle management (PLM). …


The Effects Of Direct Supervision On Therapist Behavior: A Functional Analysis, Shawn L. Thurber Mar 2005

The Effects Of Direct Supervision On Therapist Behavior: A Functional Analysis, Shawn L. Thurber

Theses and Dissertations

Live (Direct) Supervision has always been key to training therapists. However, little research has been done to determine which type of direct supervision is most effective in changing therapist behavior. This study compared bug-in-the-ear (BITE), phone-in, and computer assisted (CA) supervision. The purpose of this study was to (a) complete functional analysis of each supervision type via an alternating feedback session, to determine each therapists' most effective form of supervision; (b) determine the effect of using the most-effective form of supervision on the therapists' adherence to treatment protocols during follow-up sessions; (c) determine the effect of therapist adherence on client …


Effects Of Neuromuscular Training On The Dynamic Restraint Characteristics Of The Ankle, Christena Linford Mar 2005

Effects Of Neuromuscular Training On The Dynamic Restraint Characteristics Of The Ankle, Christena Linford

Theses and Dissertations

Objective: To examine the influence of a 6-week training program on the electromechanical delay (EMD) and reaction time of the peroneus longus muscle.

Design and Setting: The study was guided by a 2 x 2 factorial design with repeated measures on the time factor. The independent variables for this study were group (training and control) and time (pre- and post-training). Dependent variables for this study were muscle reaction time and electromechanical delay of the peroneus longus muscle.

Subjects: Thirty-six healthy, physically active, college-age (21.8 ± 2.3 yr) male and female (M = 14, F = 28, height = 173.7 ± …


Accountability For The Implementation Of Secondary Visual Arts Standards In Utah And Queensland, John K. Derby Mar 2005

Accountability For The Implementation Of Secondary Visual Arts Standards In Utah And Queensland, John K. Derby

Theses and Dissertations

Utah and the majority of states have adopted mandatory standards for visual arts, yet no accountability measures have been established. Consequently, it is impossible to determine if standards are being addressed in the art classroom and aggregate grades are subjective. Queensland, Australia instituted a system of moderated school-based assessment (moderation) in 1971, whereby assessment is accomplished locally, then verified by peer experts. Queensland ensures that standards are addressed in curricula and assessment and that exit grades are reliable and comparable. Research has shown that Utah and Queensland share comparable visual arts standards and similar demographics. Queensland moderation has been extensively …


A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau Mar 2005

A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau

Theses and Dissertations

Late Middle Eocene time marks one of the most dynamic periods of the Paleogene in the western interior of North America. Analysis of an extensive, new collection of plant, invertebrate, and vertebrae fossils from the Uinta Formation in the Uinta Basin, south of Myton, Utah, USA, provides evidence of environmental change. Paleobotanical specimens are preserved in late stage Uinta Lake sediments and coarse-grained fluvial sediments which are stratigraphically 650 to 660 m above the Green River Formation. Deposition rates estimates of 18 to 55 cm/kyr, for Uinta Lake sediments in the Uinta Basin suggest a period of 1.18 Ma to …


Simulation-Based Design Under Uncertainty For Compliant Microelectromechanical Systems, Jonathan W. Wittwer Mar 2005

Simulation-Based Design Under Uncertainty For Compliant Microelectromechanical Systems, Jonathan W. Wittwer

Theses and Dissertations

The high cost of experimentation and product development in the field of microelectromechanical systems (MEMS) has led to a greater emphasis on simulation-based design for increasing first-pass design success and reliability. The use of compliant or flexible mechanisms can help eliminate friction, wear, and backlash, but compliant MEMS are sensitive to variations in material properties and geometry. This dissertation proposes approaches for design stage uncertainty analysis, model validation, and robust optimization of nonlinear compliant MEMS to account for critical process uncertainties including residual stress, layer thicknesses, edge bias, and material stiffness. Methods for simulating and mitigating the effects of non-idealities …


A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant Mar 2005

A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant

Theses and Dissertations

In addition to a loss of potential revenues from Utah's $393 million sport fishing industry, the state expends millions of dollars every year on costs associated with whirling disease mitigation and prevention. A state fish hatchery at Midway, Utah was closed when the shallow unconfined aquifer being used for fish culture by spring discharge was deemed to be contaminated by whirling disease. An alternative water source may exist in a confined aquifer below this contaminated unconfined aquifer. However, the complex hydrostratigraphy presents a challenge in determining if this source is a viable resource for fish culture. Geological, physical, chemical, geophysical, …


Two-Photon Ionization Of The Calcium 4s3d 1d2 Level In An Optical Dipole Trap, Jared Estus Daily Mar 2005

Two-Photon Ionization Of The Calcium 4s3d 1d2 Level In An Optical Dipole Trap, Jared Estus Daily

Theses and Dissertations

This thesis reports an optical dipole trap for atomic calcium. The dipole trap is loaded from a magneto-optical trap (MOT) of calcium atoms cooled near the Doppler limit (~1 mK). The dipole trap is formed by a large-frame argon ion laser focused to 20 microns into the center of the MOT. This laser runs single-line at 488 nm with a maximum power of 10.6 watts. These parameters result in a trap of 125 mK for calcium atoms in the 4s3d 1D2 state. The 488 nm light also photo-ionizes the trapped atoms due to a near-resonant transition to the 4s4f 1F3 …


The Use Of Graphics, Animation, And Interactivity In A Computer-Based Lesson On Light In Digital Space, Alexander Phillip Vance Mar 2005

The Use Of Graphics, Animation, And Interactivity In A Computer-Based Lesson On Light In Digital Space, Alexander Phillip Vance

Theses and Dissertations

A discussion of the design, development, and evaluation of a computer-based lesson treating the subject of how light is represented in digital space. The report contains an analysis of the need for the project, a description of the product itself, and the methods and results of the evaluation. It also contains a literature review that discusses the supporting research concerning instructional graphics, animation and interactivity, as well as instructional design in general.


A Statistical Performance Model Of Homogeneous Raidb Clusters, Brandon Lamar Rogers Mar 2005

A Statistical Performance Model Of Homogeneous Raidb Clusters, Brandon Lamar Rogers

Theses and Dissertations

The continual growth of the Internet and e-commerce is driving demand for speed, reliability and processing power. With the rapid development and maturation of e-commerce, the need for a quick access to large amounts of information is steadily rising. Traditionally, database systems have been used for information storage and retrieval. However, with online auctions, rapid Internet searches, and data archival, the need for more powerful database systems is also growing. One type of distributed database is called Redundant Arrays of Inexpensive Databases (RAIDb). RAIDb clusters are middleware-driven to promote interoperability and portability. RAIDb clusters allow for multiple levels of data …


Finite Approximations To The Second-Order Properties Closure In Single Phase Polycrystals, Brent L. Adams, Xiang Gao, Surya R. Kalidindi Mar 2005

Finite Approximations To The Second-Order Properties Closure In Single Phase Polycrystals, Brent L. Adams, Xiang Gao, Surya R. Kalidindi

Faculty Publications

This work was supported at Brigham Young University and Drexel University by a grant from the US Army Research Office, through the Metallurgy Program headed by Dr. David Stepp. Extension of the first-order theory of microstructure design to considerations of morphological texture is addressed in this paper. The main challenges include the r-interdependence of the 2-point correlation functions of lattice orientation, construction of the corresponding microstructure hull, and its corresponding properties closure(s). It is shown that the correlation functions can be expressed in terms of an intermediate construct, called the texture function; the correlation functions have quadratic dependence in the …


Thor: The Hybrid Online Repository, Timothy W. Van Der Horst Mar 2005

Thor: The Hybrid Online Repository, Timothy W. Van Der Horst

Theses and Dissertations

Digital credentials enable users to perform secure interactions by proving either their identity or that they posses certain attributes. Special care is taken to protect these credentials and their associated private keys during transaction time. However, protection of these items outside of the transaction is often delegated to a secure credential repository. A mobile environment creates significant challenges for secure repositories. We examine these challenges with respect to existing repository practices and produce a set of requirements that a repository must meet in order to cope with the harshness of a mobile environment. We also present the design and implementation …


Sea Ice Mapping Method For Seawinds, David G. Long, Hyrum S. Anderson Mar 2005

Sea Ice Mapping Method For Seawinds, David G. Long, Hyrum S. Anderson

Faculty Publications

A sea ice mapping algorithm for SeaWinds is developed that incorporates statistical and spatial a priori information in a modified maximum a posteriori (MAP) framework. Spatial a priori data are incorporated in the loss terms of a Bayes risk formulation. Conditional distributions and priors for sea ice and ocean statistics are represented as empirical histograms that are forced to conform to a set of expected histograms via principal component filtering. Tuning parameters for the algorithm allow adjustments in the algorithm's performance. Results of the algorithm exhibit high correlation with the Remund-Long sea ice mapping algorithm for SeaWinds and the Special …


Optical Detection Of Ultracold Neutral Calcium Plasmas, Elizabeth Ann Cummings Feb 2005

Optical Detection Of Ultracold Neutral Calcium Plasmas, Elizabeth Ann Cummings

Theses and Dissertations

We demonstrate an optical method to detect calcium ions in an ultracold plasma. We probe the plasma with a 397 nm laser beam tuned to a calcium ion transition. The probe laser beam is focused to a 160 µm waist allowing fine spatial resolution. Ions are detected by measuring fluorescence using a Photo-Multiplier Tube (PMT). The signal, an average of 4000 acquisitions, has a temporal resolution of 120 ns. We present the details of this method, potential improvements, and prospects of imaging the expanding plasma ions. We also present preliminary work on spatially resolved absorption measurements, as well as additional …