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Tight Double-Change Covering Designs, Kristen A. Lindbloom

Research Papers

No abstract provided.

Improvement Of Hydraulic And Water Quality Renovation Functions By Intermittent Aeration Of Soil Treatment Areas In Onsite Wastewater Treatment Systems, José A. Amador, David A. Potts, George W. Loomis, David V. Kalen, Erika L. Patenaude, Josef H. Görres

Natural Resources Science Faculty Publications

We tested intermittent aeration of the soil treatment area (STA) of onsite wastewater treatment systems (OWTS) for its ability to restore and maintain STA hydraulic flow and improve the water quality functions of conventional OWTS. Evaluation was conducted on hydraulically-failed conventional OWTS at three state-owned medical group homes in Washington County, RI, USA. Testing was conducted in two phases, with Phase I (before intermittent soil aeration (ISA)) comprising the first 6 months of the study, and Phase II (during ISA) the remaining 7 months. Intermittent soil aeration restored STA hydraulic function in all three systems despite a marked reduction in …

Nonlinear Modeling Of A Sustainable Material, Jorien Gill Baza

Master's Theses

This study developed a nonlinear constitutive model for a sustainable orthotropic material. Existing methods for constitutive models of wood were improved upon to include the nonlinear stress-strain response not only in the two orthogonal axes but at any orientation to the strong axis of the material. This method also simplifies the nonlinear stress-strain relationships into bilinear stress-strain curves which can be valuable in hand calculations as well as finite-element analyses. The effectiveness of the proposed constitutive model is demonstrated by comparing bilinear stress-strain predictions to experimental data.

Control Of Longitudinal Pitch Rate As Aircraft Center Of Gravity Changes, John Andres Cadwell Jr.

Master's Theses

In order for an aircraft to remain in stable flight, the center of gravity (CG) of an aircraft must be located in front of the center of lift (CL). As the center of gravity moves rearward, pitch stability decreases and the sensitivity to control input increases. This increase in sensitivity is known as pitch gain variance. Minimizing the pitch gain variance results in an aircraft with consistent handling characteristics across a broad range of center of gravity locations.

This thesis focuses on the development and testing of an open loop computer simulation model and a closed loop control system to …

Terrain Impostors, William Hamilton Hess

Master's Theses

Interactive software applications which need to render large terrain meshes can suffer from slow frame rates if the geometry of the terrain is sufficiently dense. However, the viewing angle to many distant features of the terrain does not change rapidly with respect to time. If the movement of the viewing position is limited to continuous motion and restrained to a known speed, many terrain features may be rendered once in high detail and reused for several frames.

This thesis proposes a method to increase the rendering speed of large complex terrains by splitting the terrain into contiguous chunks. If a …

Pisa In Brief : Highlights From The Full Australian Report : Challenges For Australian Education : Results From Pisa 2009 : The Pisa 2009 Assessment Of Students' Reading, Mathematical And Scientific Literacy, Sue Thomson, Lisa De Bortoli, Marina Nicholas, Kylie Hillman, Sarah Buckley

OECD Programme for International Student Assessment (PISA) Australia

PISA in Brief summarises the results from the Programme for International Student Assessment (PISA) 2009 assessment of students’ reading, mathematical and scientific literacy skills. It tells us about how students performed in the assessment and describes some wider findings about what lies behind their results. PISA 2009 assessed students’ capacities to apply knowledge and skills in reading, mathematical and scientific literacy. More assessment time was given to reading literacy, as this was the main focus for this cycle.

Ultrafast Time Domain Optics Of Single-Cycle Laser Pulse Interaction With Materials, Ufuk Parali

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

In this thesis, interaction of an ultrashort single-cycle pulse (USCP) with a bound electron without ionization is studied for the first time. For a more realistic mathematical description of USCPs, Hermitian polynomials and combination of Laguerre functions are used for two different single-cycle excitation cases. These single-cycle pulse models are used as driving functions for the classical approach to model the interaction of a bound electron with an applied field. Two different new novel time domain modification techniques are developed for modifying the classical Lorentz damped oscillator model in order to make it compatible with the USCP excitation. In the …

Modeling And Simulation Of Tunable Photonic Crystals, Weiqing Yang

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Photonic crystals (PhCs) have wavelength scale periodically alternating refractive indexes. Photon in such structures is subject to strong scattering, experiencing distinctive redistribution of energy, yielding interesting properties such as photonic band gaps, field enhancement, strong nonlinear optic effects and photon confinement. The modified fields also alter the propagation of light beams. By proper setup, super collimation could be realized in PhCs where beams can travel long distance without spreading, while no waveguide structure is used. Redirection of light can extend the refraction to negative range, without violating physics rules. This distinguished phenomenon has been envisioned as the core mechanism for …

The Möbius Geometry Of Hypersurfaces, Ii, Michael Bolt

University Faculty Publications and Creative Works

No abstract provided.

Conservation From The Bottom-Up: Human, Financial, And Natural Capital As Determinants Of Resilient Livelihoods In Kigoma Rural, Tanzania, Yared J. Fubusa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rhetoric of "community-based conservation" has gained prominence among development specialists and environmentalists, yet such projects are often implemented from the top-down in Africa. This dissertation contends that only a bottom-up approach can foster resilient livelihoods and environmental stewardship.

This study focused on determinants of household resilience within a poverty-stricken agricultural community near Gombe Stream National Park (GSNP) in western Tanzania. The research purpose was to explore: 1) relationships between villagers and GSNP management; 2) how groups and individuals view priority livelihood problems and solutions; 3) various attributes of households; and 4) perceived trends for household resilience and how these are …

Complexity And Power Consumption In Stochastic Iterative Decoders, Keyur M. Payak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Stochastic iterative decoding is a novel method to decode the bits received at the end of a communication channel and to control the rate of error happening in the message bits due to noise being injected into the channel. This decoder uses stochastic computation that is based on manipulation of probabilities from a random sequence of digital bits. Hardware needed for implementing this arithmetic is very simple and can be completely implemented using simple digital complementary metal oxide gates. This helps the decoder to be technology independent, which is a major advantage over its digital and analog counterparts, which are …

Using Formative Student Feedback: A Continuous Quality Improvement Approach For Online Course Development, Kristy T. Bloxham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this study was to examine the use of frequent, anonymous student course surveys as a tool in supporting continuous quality improvement (CQI) principles in online instruction. The study used a qualitative, multiple-case design involving four separate online courses. Analysis methods included pattern matching/explanation building, time series analysis, and thematic analysis. Findings suggested that instructors used student feedback to make course changes that alleviated technical difficulties, added and clarified content, and contributed to future course changes. Students and instructors responded positively to the opportunity to give and receive anonymous feedback and felt that it helped improve the course. …

Labyrinth Weirs, Brian Mark Crookston

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Labyrinth weirs are often a favorable design option to regulate upstream water elevations and increase flow capacity; nevertheless, it can be difficult to engineer an optimal design due to the complex flow characteristics and the many geometric design variables of labyrinth weirs. This study was conducted to improve labyrinth weir design and analyses techniques using physical-model-based data sets from this and previous studies and by compiling published design methodologies and labyrinth weir information.

A method for the hydraulic design and analyses of labyrinth weirs is presented. Discharge coefficient data for quarter-round and half-round labyrinth weirs are offered for sidewall angles …

Architecture, Modeling, And Analysis Of A Plasma Impedance Probe, Magathi Jayaram

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Variations in ionospheric plasma density can cause large amplitude and phase changes in the radio waves passing through this region. Ionospheric weather can have detrimental effects on several communication systems, including radars, navigation systems such as the Global Positioning Sytem (GPS), and high-frequency communications. As a result, creating models of the ionospheric density is of paramount interest to scientists working in the field of satellite communication.

Numerous empirical and theoretical models have been developed to study the upper atmosphere climatology and weather. Multiple measurements of plasma density over a region are of marked importance while creating these models. The lack …

Assessment Of College Students' Understanding Of The Equals Relation: Development And Validation Of An Instrument, Gregory D. Wheeler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Research indicates that many elementary students do not comprehend that the equal sign is an indication that an equality relation exists between two structures. Instead, they perceive the equal sign as an indication that a particular procedure is to be performed. As students mature, and as their exposure to the equal sign and equality relations in multiple contexts increases, most obtain the ability to interpret the equal sign as an indicator of an equivalence relation. Incorrect usages of the equal sign, however, by post-algebra students indicate a tendency for students to regress back to a comprehension of the equal sign …

Retrieval Of Aerosol Mass Concentration From Elastic Lidar Data, Christian C. Marchant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agricultural aerosol sources can contribute significantly to air pollution in many regions of the country. Characterization of the aerosol emissions of agricultural operations is required to establish a scientific basis for crafting regulations concerning agricultural aerosols. A new lidar instrument for measuring aerosol emissions is described, as well as two new algorithms for converting lidar measurements into aerosol concentration data. The average daily aerosol emission rate is estimated from a dairy using lidar.

The Aglite Lidar is a portable scanning lidar for mapping the concentration of particulate matter from agricultural and other sources. The instrument is described and performance and …

Recreation Resource Impacts In The Bear Lake Road Corridor Of Rocky Mountain National Park, Colorado, Usa: An Assessment Of Resource Conditions And Visitor Perceptions, Ashley L. D'Antonio

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Visitor use in parks and protected areas inevitably leads to resource impacts. In order to effectively manage for resource impacts, it is important for managers to not only understand ecological aspects of their system but sociological aspects as well. The two papers presented in this thesis used integrated approaches to better understand the current level of resource impacts within the Bear Lake Road Corridor of Rocky Mountain National Park and to explore visitor perceptions of these impacts. The first paper used traditional monitoring and assessment techniques, as well as recently developed methodologies, to determine the current level of resource impacts …

An Evolutionary Approach To Optimization Of Compound Stock Trading Indicators Used To Confirm Buy Signals, Allan W. Teeples

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis examines the application of genetic algorithms to the optimization of a composite set of technical indicator filters to confirm or reject buy signals in stock trading, based on probabilistic values derived from historical data. The simplicity of the design, which gives each filter within the composite filter the ability to act independently of the other filters, is outlined, and the cumulative indirect effect each filter has on all the others is discussed. This system is contrasted with the complexity of systems from previous research that attempt to merge several indicator filters together by giving each one a weight …

Incorporating Spatial Information Into Gas Plume Detection In Hyperspectral Imagery, Cameron S. Grant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Detection of chemical plumes in hyperspectral data is a problem having solutions that focus on spectral information. These solutions neglect the presence of the spatial information in the scene. The spatial information is exploited in this work by assignment of prior probabilities to neighborhood configurations of signal presence or absence. These probabilities are leveraged in a total probability approach to testing for signal presence in a pixel of interest. The two new algorithms developed are named spatial information detection enhancement (SIDE) and bolt-on SIDE (B-SIDE). The results are explored in comparison to the clutter matched filter (CMF), a standard spectral …

Toward The Validation Of Depth-Averaged, Steady-State Simulations Of Fluvial Flows Using Three-Dimensional, Steady-State, Rans Turbulence Models, Pedro Abdiel Mateo Villanueva

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Calculations of fluvial flows are strongly influenced by geometry complexity and large overall uncertainty on every single measurable property, such as velocity and shear. Moreover, a considerable portion of the data obtained from computational simulations arose from two-dimensional, steady-state models. The present work states a different approach to perform computer-based simulations and analyze fluvial flows. For the first part, the suitability of OpenFOAM to be used as the main CFD solver to analyze fluvial flows is studied. Initially, two well documented channel configurations are computationally studied using OpenFOAM. Finally, these results are compared to the output obtained from one of …

Factors Affecting Gunnison Sage-Grouse (Centrocercus Minimus) Conservation In San Juan County, Utah, Phoebe R. Prather

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to loss of habitat, Gunnison sage-grouse (Centrocercus minimus) currently occupy 8.5% of their presumed historical range. One population survives in Utah, occurring in San Juan County. The Gunnison Sage-grouse Rangewide Conservation Plan and the San Juan County Gunnison Sage-grouse Conservation Plan recommended management strategies to address identified conservation threats to the Utah population. I addressed three conservation strategies identified in the plans: 1) creation and enhancement of brood-rearing areas; 2) assessment of habitat conditions within the Gunnison Sage-grouse Conservation Area; and 3) prevention or reduction of perching events by avian predators on distribution line power poles.

From 2007-2009, I …

Effect Of Mica Content On Surface Infiltration Of Soils In Northwestern Kern County, California, Steven Keyes Stakland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A soils infiltration rate (IR) is the measured rate that soil is able to absorb water, either from precipitation or irrigation. A low IR can cause damage to crops if the necessary amount of water cannot penetrate to the plant roots in the time needed. The damage can be common in permanent plantings such as almond and pistachio orchards where regular tillage is avoided. This indicates a physical aspect to the problem because tillage increases IR. However, there is also an electrochemical side to infiltration problems because certain calcium surfactant treatments can increase IR. Various other methods have been used …

Pervasive Thermal Consequences Of Stream-Lake Interactions In Small Rocky Mountain Watersheds, Usa, Jessica D. Garrett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Limnologists and stream ecologists acknowledge the fundamental importance of temperature for regulating many ecological, biological, chemical, and physical processes. I investigated how water temperatures were affected by hydrologic linkages between streams and lakes at various positions along surface water networks throughout several headwater basins in the Sawtooth and White Cloud Mountains of Idaho (USA). Temperatures of streams and lakes were measured for up to 27 months in seven 6 – 41 km² watersheds, with a range of lake influence. When they were ice-free, warming in lakes resulted in dramatically warmer temperatures at lake outflows compared to inflow streams (midsummer …

Ab Initio Search For Novel Bxhy Building Blocks With Potential For Hydrogen Storage, Jared K. Olson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

On-board hydrogen storage presents a challenging barrier to the use of hydrogen as an energy source because the performance of current storage materials falls short of platform requirements. Because boron is one of the lightest chemical elements that can form strong covalent bonds with hydrogen, it provides an excellent opportunity to design new lightweight materials on the basis of novel boron hydride building blocks. Realizing this potential requires an understanding of the electronic structure, chemical bonding, and stability of neutral and anionic B_xH_y clusters with variable stoichiometry. While a large number of boron hydride compounds are known, …

Spatial Epidemiology Of Birth Defects In The United States And The State Of Utah Using Geographic Information Systems And Spatial Statistics, Samson Y. Gebreab

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Oral clefts are the most common form of birth defects in the United States (US) and the State of Utah has among the highest prevalence of oral clefts in the nation. The overall objective of this dissertation was to examine the spatial distribution of oral clefts and their linkage with a broad range of demographic, behavioral, social, economic, and environmental risk factors through the application of Geographic Information Systems (GIS) and spatial statistics. Using innovative linked micromaps plots, we investigated the geographic patterns of oral clefts occurrence from 1998 to 2002 and their relationships with maternal smoking rates and proportion …

Spatial Light Dilution As A Technique For Conversion Of Solar Energy To Algal Biomass, Daniel J. Dye

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A photobioreactor has been designed and developed to efficiently utilize solar irradiance through spatial dilution of sunlight. The concept of spatial light dilution is simple: incident sunlight is spread over a large surface area, thus reducing the photon flux density of the light. The implementation of this technique, however, is difficult. The reactor described within uses a new approach to spatial light dilution, utilizing recently-developed optical components to diffuse concentrated sunlight inside an algae culture. Preliminary productivity tests indicate a 2-3 fold increase in productivity per unit aperture (sunlight collection area) over a control reactor with direct-sunlight. Aperture productivity of …

Kinetic, Mechanistic, And Structural Investigation Of Features Controlling Stereoselectivity Of (R)- And (S)-Hydroxypropyl Com Dehydrogenases From Xanthobacter Autrophicus Strain Py2, Dariusz Adam Sliwa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Enantiopure alcohols are valuable intermediates in fine organic synthesis, in particular for preparation of biologically active compounds. The necessity of preparing single enantiomer drugs in an optically pure form has triggered much research, especially in the pharmaceutical industry. The biocatalytical production of chiral alcohols by alcohol dehydrogenase enzymes is characterized by the asymmetric reduction of the corresponding ketones, usually with high degree of stereoselectivity. The commercial value of the enzymes as stereoselective biocatalysts has been a significant driving force in understanding features that control their mechanism of catalysis and stereoselectivity. This work focuses on two enantiocomplementary dehydrogenase enzymes ((R …

Who Wins And Who Loses? A Community Approach To Understanding The Well-Being Of Boomtown Residents, Douglas Alan Malloy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this thesis is to accurately identify residents of a boomtown who are either experiencing a higher level of well-being, or lower level of well-being. By definition, we consider the former to be winning, and the latter to be losing. Multivariate ordinary least squares regression analyses help to distinguish between winners and losers by generating statistical coefficients which will show both strength and direction of the relationship between individuals and various indicators of social well-being.

The data used in this thesis are from a community impact study issued in the spring of 2009, to residents of …

Estimates Of The Hydraulic Parameters Of Aquifers In Cache Valley, Utah And Idaho, Paul C. Inkenbrandt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hydraulic parameters of aquifers in Cache Valley were compiled from existing but largely unpublished data, from specific capacity data reported in well drillers' records, and from aquifer tests conducted for this study. A GIS database was also created to organize this information.

A complete and thorough literature review was performed, which included obtaining unpublished aquifer test data from state and federal agencies, as well as reviewing Drinking Water Source Protection plans for each municipality in the valley.

Well drillers' records were obtained from the Utah Division of Water Rights website and examined for pertinent information. Screened unit intervals from 1,314 …

Transportation Network Resiliency: A Fuzzy Systems Approach, Nayel Urena Serulle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Every day the dependence on transportation grows as local, regional, national, and international independence increases. Resilient transportation systems are needed to secure the highest possible level of service during disruptive events, including natural and man-made disasters. Because of limited resources, decision makers need guidance on how, when, and where to invest to improve resiliency of their networks. The research objective is to develop a method to assess and quantify resiliency, at pre-event conditions, using a fuzzy inference approach. This research expands previous work, refining key variable definitions, adjusting model interactions, and increasing transparency between metrics. This thesis presents the method …