Digital Commons Network^™

Wind Scatterometry With Improved Ambiguity Selection And Rain Modeling, David W. Draper

Theses and Dissertations

Although generally accurate, the quality of SeaWinds on QuikSCAT scatterometer ocean vector winds is compromised by certain natural phenomena and retrieval algorithm limitations. This dissertation addresses three main contributers to scatterometer estimate error: poor ambiguity selection, estimate uncertainty at low wind speeds, and rain corruption. A quality assurance (QA) analysis performed on SeaWinds data suggests that about 5% of SeaWinds data contain ambiguity selection errors and that scatterometer estimation error is correlated with low wind speeds and rain events.

Ambiguity selection errors are partly due to the "nudging" step (initialization from outside data). A sophisticated new non-nudging ambiguity selection approach …

Selecting Appropriate Product Concepts For Manufacture In Developing Countries, Danielle Johnson

Theses and Dissertations

There is a noticeable lack of production of indigenously engineered and manufactured products in Less Developed Countries (LDC's). Few products developed in these LDC's could be viable in competitive markets or even sold as components and supplies to other manufacturers of competitive goods. Assumintg that these less developed countries do not innovate and manufacture because they cannot, the next logical question to ask is why can they not?

This thesis looks at the problems of manufacture and design in LDC's from the standpoint of Product Development. It begins by looking at development theories, namely top down and bottom up and …

Establishing A Quantitative Foundation For Exactly Constrained Design, Alisha M. Hammond

Theses and Dissertations

Exactly constrained (EC) design is a robust design method which can be used for mechanical assemblies. It entails using the minimum number of constraints to eliminate all desired motion.

While found by some engineers in industry to have many benefits (including robust assembly, no binding or play, ease of assembly, and the ability to tolerate the wear of parts), EC designs remain somewhat unrecognized by academia. One reason for this minimal exposure may be the lack of a quantitative foundation for such designs. This thesis describes the history and current background for EC designs, and it also begins to develop …

An Accurate Vo2max Non-Exercise Regression Model For 18 To 65 Year Old Adults, Danielle I. Bradshaw

Theses and Dissertations

The purpose of this study was to develop a regression equation to predict VO2max based on non-exercise (N-EX) data. All participants (N = 100), aged 18-65 years old, successfully completed a maximal graded exercise test (GXT) to assess VO2max (mean ± SD; 39.96 mL∙kg-¹∙min&sup-1; ± 9.54 mL∙kg-¹∙min-¹). The N-EX data collected just before the maximal GXT included the participant's age, gender, body mass index (BMI), perceived functional ability (PFA) to walk, jog, or run given distances, and current physical activity (PA-R) level. Multiple linear regression generated the following N-EX prediction equation (R = .93, SEE = 3.45 mL∙kg-¹∙min-¹, %SEE = …

Analysis Of Weight-Related Advertisements And Nutrition Articles In Popular Women's Magazines, Jennifer Cardall Jacobson

Theses and Dissertations

Objective: The purpose of this study was to discover whether the weight-related messages and themes from food advertisements in women's magazines reinforce or contradict the messages communicated in nutrition-related articles focusing on weight control within the same magazines.

Design: Content analysis of 48 issues of weight-related content six popular women's magazines, 2001-2002. There were three magazines in each of two categories, "homemaking" and "health." All food and nutrition advertisements were analyzed (n=954), along with all nutrition articles (n=336). Advertisements and articles were identified as being either weight-related or non-weight-related. Type of food/product advertised, claims used to market the product, and …

Rotational Molding Of Acrylonitrile-Butadiene-Styrene Polymers And Blends, Mark Grant Spencer

Theses and Dissertations

The development of acrylonitrile-butadiene-styrene (ABS) resins for use in rotational molding would provide a medium performance material, thus opening doors to new markets for the rotational molding industry. Unfortunately, ABS resins have shown serious problems during the rotational molding process, namely discoloration, bridging, and poor impact strength. It is believed that these effects are due to degradation of the carbon-carbon double bond in the butadiene, through attack by either oxygen or heat. Previous efforts have shown some success in addressing these issues. However, additional improvements are necessary to make ABS resins commercially viable to rotational molders. This study, fourth in …

Delineation Of Mass Movement Prone Areas By Landsat 7 And Digitial Image Processing, Shiloh Marie Howland

Theses and Dissertations

The problem of whether Landsat 7 data could be used to delineate areas prone to mass movement, particularly debris flows and landslides, was examined using three techniques: change detection in NDVI (Normalized Difference Vegetation Index), change detection in band 5, and the tasseled cap transformation. These techniques were applied to areas that had recently experienced mass movement: Layton, Davis County and Alpine, Spanish Fork Canyon and Santaquin, Utah County. No distinctive spectral characteristics were found with any of these techniques with two possible explanations: 1. That despite improved spatial resolution in Landat 7 over its predecessors and improved digital image …

Satellite Scatterometers: Calibration Using A Ground Station And Statistical Measurement Theory, Peter Kenneth Yoho

Theses and Dissertations

Satellite scatterometers have recently gained popularity due to their unique ability to measure global geophysical data on a daily basis. Increased interest in scatterometry mandates improved design and calibration of these instruments. This dissertation presents new techniques for scatterometer calibration and addresses issues related to the design of future instruments and applications. First, the use of a calibration ground station is considered. A new methodology is established for calibration of SeaWinds, NASA's current scatterometer, using a receive-only ground station. Principles of the methodology are implemented, new analysis techniques developed, and important results obtained for instrument timing, frequency, power, position, and …

Design And Development Of The Self-Efficacy For Musical Studies Scale, Kathryn Rae Pearson

Theses and Dissertations

Scale development in psychological studies is an area of intense growth (Clark & Watson, 1995). This report builds upon academic interest in the value of producing viable measurement tools. The purpose of this research project was to evaluate a self-efficacy measurement scale intended to determine individual music students' perceptions of capability. The areas of interest were four self-regulatory skill domains: strategy use, planning, monitoring, and evaluating in two music environments: independent practicing and performance.

This report describes the development and analysis of the Self-efficacy for Musical Studies (SEMS) scale. The report includes statistical analysis of the response data from formative …

Modeling The Transient Response Of A Thermosyphon, James Kirk Storey

Theses and Dissertations

Thermosyphon transient operation was numerically modeled. The numerical model presented in this work overcame the limitations of previous studies by including transient conduction in the vessel wall, shear stress between the rising vapor and the falling film in the thermosyphon, the influence of the mass in the liquid pool in the evaporator, and by using a more refined and accurate numerical grid. Unique to this model was the accounting for temporal changes in the effective length of the vapor space due to the expanding and contracting of non-condensable gases in the vapor space. The model assumed quasi-steady one-dimensional vapor flow, …

Thermodynamic Property Prediction For Solid Organic Compounds Based On Molecular Structure, Benjamin T. Goodman

Theses and Dissertations

A knowledge of thermophysical properties is necessary for the design of all process units. Reliable property prediction methods are essential because reliable experimental data are often not available due to concerns about measurement difficulty, cost, scarcity, safety, or environment. In particular, there is a lack of prediction methods for solid properties. Predicted property values can also be used to fill holes in property databases to understand more fully compound characteristics. This work is a comprehensive analysis of the prediction methods available for five commonly needed solid properties. Where satisfactory methods are available, recommendations are made; where methods are unsatisfactory in …

Predictors Of General Medical Use Among Individuals Seeking Therapy For Marital And Family Problems, Jacob D. Christenson

Theses and Dissertations

A number of studies have examined variables associated with medical use. However, most of the studies deal with samples that are not easily generalizable to other populations. In particular, no study is known to have looked at general medical use among people seeking services for marital and family problems. In this study, medical use of participants from the marriage and family therapy services at Brigham Young University Comprehensive Clinic was investigated to determine the best predictors of general medical use. Best subsets multiple linear regression showed that the best overall predictors of general medical use were anxiety and hostility.

A Closed-Form Dynamic Model Of The Compliant Constant-Force Mechanism Using The Pseudo-Rigid-Body Model, Cameron Boyle

Theses and Dissertations

A mathematical dynamic model is derived for the compliant constant-force mechanism, based on the pseudo-rigid-body model simplification of the device. The compliant constant-force mechanism is a slider mechanism incorporating large-deflection beams, which outputs near-constant-force across the range of its designed deflection. The equation of motion is successfully validated with empirical data from five separate mechanisms, comprising two configurations of compliant constant-force mechanism. The dynamic model is cast in generalized form to represent all possible configurations of compliant constant-force mechanism. Deriving the dynamic equation from the pseudo-rigid-body model is useful because every configuration is represented by the same model, so a …

Predicting Drag Polars For Micro Air Vehicles, Mark Elden Luke

Theses and Dissertations

Drag polars for three Micro Air Vehicles (MAVs) were measured at Reynolds numbers of 70,000, 50,000, 30,000, and 10,000 and compared to predictions generated using the classical approach. The MAVs tested had different configurations and aspect ratios varying from 1.2 to 1.6 and ratios of wetted surface area to planform area from 2.6 to 3.9.

A force balance was used to measure the lift and drag on the MAVs at angles of attack ranging from -5 degrees (or -10 degrees) to 10 degrees. The force balance allowed the MAVs to rotate in the pitching axis. The MAV angle of attack …

Viennese Feuilleton During The Early 1920s: Description And Analysis Of Bertha Pauli's Biographical Sketches As Contributions To A Literary Genre, Ruth Kirsten Seppi

Undergraduate Honors Theses

Bertha Pauli belongs to a class of writers (women) who are often overlooked, writing in a style (feuilleton) that is under-recognized for its literary value. Her writings have never been systematically analyzed before despite their volume and prominence in the Vienna of the 1920s. The first half of this thesis deals with the form of feuilleton, establishing a context in which to study Pauli’s works. The second half describes the political content of Pauli’s biographical feuilletons and demonstrates her skill as a persuasive writer. Feuilletons were a popular form of journalistic writing from the eighteenth century up until the Second …

Swift Electro-Optic Modulator, Geofrey Craig Harston

Theses and Dissertations

The Silicon Wafer Integrated Fiber Technology, SWIFT, is a novel platform for the development of photonic devices. SWIFT is comprised of an optical fiber, specifically a D-fiber in this work, embedded into a V-groove etched into a silicon wafer. This provides a method to secure the fiber and allows the use of standard semiconductor industry equipment and techniques in latter processing for device fabrication.

The SWIFT platform is used as the basis for the development of a polarimetric in-fiber electro-optic modulator. The modulator is based on the application of a nonlinear optical polymer, NLOP, film into the evanescent field of …

Large Eddy Simulation Based Turbulent Flow-Induced Vibration Of Fully Developed Pipe Flow, Matthew Thurlow Pittard

Theses and Dissertations

Flow-induced vibration caused by fully developed pipe flow has been recognized, but not fully investigated under turbulent conditions. This thesis focuses on the development of a numerical Fluid-Structure Interaction (FSI) model that will help define the relationship between pipe wall vibration and the physical characteristics of turbulent flow. Commercial FSI software packages are based on Reynolds Averaged Navier-Stokes (RANS) fluid models, which do not compute the instantaneous fluctuations in turbulent flow. This thesis presents an FSI approach based on Large Eddy Simulation (LES) flow models, which do compute the instantaneous fluctuations in turbulent flow. The results based on the LES …

Compliant Centrifugal Clutches: Design, Analysis, And Testing, Nathan B. Crane

Theses and Dissertations

Existing classes of centrifugal clutch concepts were reviewed. The pseudo-rigid-body model (PRBM), rigid-body replacement synthesis, force-deflection analysis, compliance potential evaluation, and compliant concept evaluation were used to develop effective new centrifugal clutch concepts. These methods helped develop and model four novel compliant centrifugal clutch designs, model two existing designs, and identify a concept with excellent potential for low-cost centrifugal clutch applications. This concept, the floating opposing arm (FOA) clutch, doubles the torque capacity metric relative to existing compliant designs. Torque and engagement speed models for this clutch were developed and verified against four prototype clutches. Additional novel designs devel-oped through …

A Five-Zone Model For Direct Injection Diesel Combustion, Rich Asay

Theses and Dissertations

Recent imaging studies have provided a new conceptual model of the internal structure of direct injection diesel fuel jets as well as empirical correlations predicting jet development and structure. This information was used to create a diesel cycle simulation model using C language including compression, fuel injection and combustion, and expansion processes. Empirical relationships were used to create a new mixing-limited zero-dimensional model of the diesel combustion process. During fuel injection five zones were created to model the reacting fuel jet: 1) liquid phase fuel 2) vapor phase fuel 3) rich premixed products 4) diffusion flame sheath 5) surrounding bulk …

Theory, Design, And Fabrication Of Diffractive Grating Coupler For Slab Waveguide, Kevin Randolph Harper

Theses and Dissertations

This thesis presents the theory design and fabrication of a diffractive grating coupler. The first part of the design process is to choose the period of the grating coupler based on the desired coupling angle. The second part of the design process is to choose the geometry of the grating that gives maximum coupling efficiency based on rigorous analyses.

The diffraction gratings are fabricated by recording the interference between two waves in photoresist. The waveguide is fabricated from silicon nitride that is deposited by chemical vapor deposition. The diffraction grating recording assembly is described along with the grating coupler fabrication …

A Descriptive Performance Model Of Small, Low Cost, Diskless Beowulf Clusters, Curtis R. Nielson

Theses and Dissertations

Commodity supercomputing clusters known as Beowulf clusters, have become a low cost alternative to traditional supercomputers. Beowulf clusters combine inexpensive computers and specialized software to achieve supercomputing power. The processing nodes in a diskless Beowulf cluster do not have a local hard disk unlike the nodes in most commodity clusters. Research has provided performance information for diskless clusters built with expensive, high performance equipment. Beowulf clusters use commodity off-the-shell hardware, and little information is available about their performance. This research includes the construction of several diskless Beowulf clusters. Using the NAS Parallel Benchmarks, the performance of these clusters was measured. …

Schema Matching And Data Extraction Over Html Tables, Cui Tao

Theses and Dissertations

Data on the Web in HTML tables is mostly structured, but we usually do not know the structure in advance. Thus, we cannot directly query for data of interest. We propose a solution to this problem for the case of mostly structured data in the form of HTML tables, based on document-independent extraction ontologies. The solution entails elements of table location and table understanding, data integration, and wrapper creation. Table location and understanding allows us to locate the table of interest, recognize attributes and values, pair attributes with values, and form records. Data-integration techniques allow us to match source records …

Prehistoric Timberline Adaptations In The Eastern Uinta Mountains, Utah, Michelle Knoll

Theses and Dissertations

Excavations at a high altitude archaeological site (3350 m) in the eastern Uinta Mountains, Utah, uncovered at least three ephemeral brush structures. These temporary timberline dwellings are the highest structures excavated in Utah to date. The periods of occupation range from the early Fremont period to the post-contact era. It is believed that the Fremont occupations are logistical in nature, possibly representing male hunting parties. Logistical camps imply a departure from, and return to, a residential camp. Ethnographic studies show that most residential camps are located within proximity to culinary plants to facilitate collection by women. In the Uinta Mountains, …

A Study Of Radiofrequency Cardiac Ablation Using Analytical And Numerical Techniques, Ryan Todd Roper

Theses and Dissertations

Studies on radiofrequency (RF) ablation are often aimed at accurately predicting tissue temperature distributions by numerical solution of the bioheat equation. This thesis describes the development of an analytical solution to serve as a benchmark for subsequent numerical solutions. The solution, which was obtained using integral transforms, has the form of a surface integral nested within another surface integral. An integration routine capable of evaluating such integrals was developed and a C program was written to implement this routine. The surface integration routine was validated using a surface integral with a known analytical solution. The routine was, then, used to …

Epidemiology Of Ustilago Bullata Berk. On Bromus Tectorum L. And Implication For Biological Control, Toupta Boguena

Theses and Dissertations

The seedling-infecting pathogen Ustilago bullata Berk. is a naturally occurring biological control agent for cheatgrass (Bromus tectorum L.). The effects of temperature and nutrients on pathogen teliospore germination behavior and the effects of temperature on host seed germination were examined. The effects of temperature on sporidial proliferation, host infection in a temperature-controlled environment and in a field setting for eight populations were investigated. The infection success of Ustilago bullata on Bromus tectorum in cultivated fields as a function of seeding date, inoculation method, inoculum density, supplemental watering, and litter was also investigated. Teliospores germinated faster on potato dextrose agar than …

Incorporating Functionally Graded Materials And Precipitation Hardening Into Microstructure Sensitive Design, Mark Edward Lyon

Theses and Dissertations

The methods of MSD are applied to the design of functionally graded materials. Analysis models are presented to allow the design of compliant derailleur for a case study and constraints are placed on the design. Several methods are presented for relating elements of the microstructure to the properties of the material, including Taylor yield theory, Hill elastic bounds, and precipitation hardening.

Applying n-point statistics to the MSD framework is also discussed. Some results are presented for the information content of the 2-point correlation statistics that follow from the methods used to integrate functionally graded materials into MSD.

For the compliant …

Design And Analysis Of End-Effector Systems For Scribing On Silicon, Bennion Rhead Cannon

Theses and Dissertations

This thesis investigates end-effector systems used in a chemomechanical scribing process. Chemomechanical scribing is a method of patterning silicon to selectively deposit a monolayer of material on the surface of the silicon. This thesis details the development of a unique end-effector for chemomechanical scribing using a compliant mechanism solution. The end-effector is developed to scribe lines that have uniform geometry and produce less chipping on the surface of the silicon. The resulting scribing mechanism is passively controlled, has high lateral stiffness, and low axial stiffness. The mechanism is analyzed using the pseudo-rigid-body model and linear-elastic beam method to determine the …

The Rise And Fall Of Programmed Instruction: Informing Instructional Technologists Through A Study Of The Past, Jason K. Mcdonald

Theses and Dissertations

Instructional technologists have recently been called upon to examine the assumptions they hold about teaching and learning, and to consider how those assumptions can affect their practice of the discipline. This thesis is an examination of how the assumptions instructional technologists hold can result in instructional materials that do not accomplish the original goals the developers set out to achieve. I explored this issue by examining the case study of programmed instruction, an educational movement from the mid-20th century that promised to revolutionize education but never lived up to its potential. Programmed instruction was heavily influenced by the assumptions of …

A History Of "Especially For Youth" - 1976-1986, John Bytheway

Theses and Dissertations

The summer of 2002 marked the 26th anniversary of the youth camp “Especially for Youth” (EFY). Over 34,000 teenagers from across the United States, Canada and several foreign countries gathered on thirty-one different college campuses to attend one of the sixty-four sessions of the five-day program. Since the first session in 1976, Especially for Youth has enjoyed steady increases in attendance and popularity. Beginning in the early 1980s, the program's success reached the point that applicants were turned away because there was not enough space to house all those who wanted to attend.

EFY is sponsored by Brigham Young University …

John B. Fairbanks: The Man Behind The Canvas, Rachel Cope

Theses and Dissertations

A biographical sketch of artist John B. Fairbanks, this thesis primarily probes Fairbanks' evolution as an artist. From amateur, to art missionary, to professional artist, Fairbanks influenced his cultural surroundings in Utah and in The Church of Jesus Christ of Latter-day Saints. His commitment to his career and his impact on others significantly affected Utah and Mormon art. Thus it is important to understand and recognize the full portrait of John B. Fairbanks.

John B. Fairbanks, born on 27 December 1855, developed an interest in art while still young. Until reaching the age of thirty-four, he often worked as an …