Physical Sciences and Mathematics Commons^™

Development And Implementation Of A Bayesian Model For Sediment Transport In Fluvial Systems, Mark Schmelter

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Recent studies in the field of fluvial sediment transport underscore the difficulty in reliably estimating transport model parameters, collecting accurate observations, and making predictions due to measurement error and conceptual model uncertainty. There is a pressing need to develop models that can account for measurement error, conceptual model uncertainty, and natural variability while providing probability-based predictions as well as a means for conceptual model discrimination. The model presented in this research employs an excess shear sediment transport equation for a uni-size sediment bed developed in a Bayesian statistical framework. This statistical model provides a means to rigorously estimate distributions of …

New Symbolic Tools For Differential Geometry, Gravitation, And Field Theory (Extended Version), Charles G. Torre, Ian M. Anderson

Charles G. Torre

DifferentialGeometry is a Maple software package which symbolically performs fundamental operations of calculus on manifolds, differential geometry, tensor calculus, Lie algebras, Lie groups, transformation groups, jet spaces, and the variational calculus. These capabilities, combined with dramatic recent improvements in symbolic approaches to solving algebraic and differential equations, have allowed for development of powerful new tools for solving research problems in gravitation and field theory. The purpose of this paper is to describe some of these new tools and present some advanced applications involving: Killing vector fields and isometry groups, Killing tensors and other tensorial invariants, algebraic classification of curvature, and …

Temperature Increase Effects On Sagebrush Ecosystem Forbs: Exprimental Evidence And Range Manager Perspectives, Hilary Louise Whitcomb

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

A New Noncovalent Force: Comparison Of P∙∙∙N Interaction With Hydrogen And Halogen Bonds, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

When PH(3) is paired with NH(3), the two molecules are oriented such that the P and N atoms face one another directly, without the intermediacy of a H atom. Quantum calculations indicate that this attraction is due in part to the transfer of electron density from the lone pair of the N atom to the σ(∗) antibond of a P-H covalent bond. Unlike a H-bond, the pertinent hydrogen is oriented about 180° away from, instead of toward, the N, and the N lone pair overlaps with the lobe of the P-H σ(∗) orbital that is closest to the P. In …

On The Brink Of Change: Plant Responses To Climate On The Colorado Plateau, Seth M. Munson, Jayne Belnap, M. Schelz, Mary Moran, T. W. Caolin

Canyonlands Research Bibliography

The intensification of aridity due to anthropogenic climate change in the southwestern U.S. is likely to have a large impact on the growth and survival of plant species that may already be vulnerable to water stress. To make accurate predictions of plant responses to climate change, it is essential to determine the long-term dynamics of plant species associated with past climate conditions. Here we show how the plant species and functional types across a wide range of environmental conditions in Colorado Plateau national parks have changed with climate variability over the last twenty years. During this time, regional mean annual …

Regional And Climatic Controls On Seasonal Dust Deposition In The Southwestern Us, Marith Reheis, Frank Urban

Canyonlands Research Bibliography

Vertical dust deposition rates (dust flux) are a complex response to the interaction of seasonal precipitation, wind, changes in plant cover and land use, dust source type, and local vs. distant dust emission in the southwestern U.S. Seasonal dust flux in the Mojave-southern Great Basin (MSGB) deserts, measured from 1999 to 2008, is similar in summer-fall and winter-spring, and antecedent precipitation tends to suppress dust flux in winter-spring. In contrast, dust flux in the eastern Colorado Plateau (ECP) region is much larger in summer-fall than in winter-spring, and twice as large as in the MSGB. ECP dust is related to …

Observed Change In Sahel Rainfall, Circulations, African Easterly Waves, And Atlantic Hurricanes Since 1979, Shih-Yu (Simon) Wang, Robert R. Gillies

Plants, Soils, and Climate Faculty Publications

Here, we examine the dynamic properties associated with the recent increase in the Sahel rainfall using an ensemble of five global reanalysis datasets (1979–2010). The rainfall that has been observed to be increasing over the Sahel is accounted for by enhancements in both the tropical easterly jet and the African easterly jet, both of which are known to induce wet anomalies. Moreover, positional shifts in the African easterly jet and African easterly waves (AEWs) accompanied the northward migration of the Sahel rainband. Change in the African easterly jet and AEWs are coupled to a northward shift and amplification of convective …

Linkages To Public Land Framework: Toward Embedding Humans In Ecosystem Analyses By Using “Inside-Out Social Assessment", Joanna Endter-Wada, D. J. Blahna

Environment and Society Faculty Publications

This article presents the ‘‘Linkages to Public Land’’ (LPL) Framework, a general but comprehensive data-gathering and analysis approach aimed at informing citizen and agency decision making about the social environment of public land. This social assessment and planning approach identifies and categorizes various types of linkages that people have to public land and guides the tasks of finding and using information on people in those linkages. Linkages are defined as the ‘‘coupling mechanisms’’ that explain how and why humans interact with ecosystems, while linkage analyses are empirical investigations contextualized both temporally and geographically. The conceptual, legal, and theoretical underpinnings of …

Cosmic Voices: Searching For Signs Of Life Elsewhere In The Universe, Shane L. Larson

Public Talks

No abstract provided.

Uncertainty Associated With Modeling The Global Ionosphere, Janelle V. Jenniges, Ariel O. Acebal, Larry Gardner, Robert W. Schunk, Lie Zhu

Physics Student Research

A study has been conducted of the effect that different physical assumptions have on global models of the electron density distribution. The study was conducted with the Ionosphere Forecast Model (IFM) and the Ionosphere Plasmasphere Model (IPM) developed by Utah State University. Both physics-based, time-dependent, global models use the same empirical models for the neutral atmosphere (MSIS) and neutral wind (Horizontal Wind Model, HWM), but the altitude range, thermal structure, number of ion species, and magnetic 2ield are different. The IFM covers the altitude range from 90-1400 km, calculates the densities for four ions (NO+, O2+, N2+, O+), has a …

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 …

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 …

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 …

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 …

Residential Landscape Water Check Programs: Exploring A Conservation Tool, Diana T. Glenn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In response to drought and regional growth in the arid western United States, urban water demand management is increasingly important. Single family residences use approximately 60% of their water consumption to irrigate landscapes often in excess of plant water requirements. This study utilized a quasi-experimental design to investigate outdoor water consumption and assess the effectiveness of a landscape water check conservation program. Study objectives included describing a contextualized landscape system to reveal variables influencing water use, identifying better ways to evaluate landscape water use, and more effectively targeting and delivering water conservation programs.

The study was conducted during the 2004 …

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 …

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 …

Interclonal Variation Of Primary And Secondary Chemistry In Western Quaking Aspen And Its Influence On Ungulate Selection, Damon A. Winter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Quaking aspen (Populus tremuloides) clones within close proximity to one another can exhibit drastically different levels of browsing by ungulates. The objectives of this study were to (1) determine interclonal differences in plant chemistry between adjacent clones exhibiting different degrees of herbivory which may influence the browsing behavior and patterns of ungulates, and (2) determine if correlation exists in the levels of salicortin and tremulacin between current year's suckers and current year's growth on older trees. This second objective was meant to indicate a protocol for land managers for identifying clones meriting increased protection from herbivory after treatment …

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 …

Assessing Linkages Among Landscape Characteristics, Stream Habitat, And Macroinvertebrate Communities In The Idaho Batholith Ecoregion, Andrew C. Hill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the composition of lotic communities and the landscape processes and habitat characteristics that shape them is one of the main challenges confronting stream ecologists. In order to better understand the linkages among landscape processes, stream habitat, and biological communities and to understand how accurately our measurements represent important factors influencing biological communities, it is important to test explicit hypotheses regarding these linkages. Increasing our understanding of aquatic communities in a hierarchical context and recognizing how well our measurements represent factors structuring aquatic communities will help managers better evaluate the influence of land management practices on aquatic ecosystems, direct conservation …

Psychometric Properties Of Postsecondary Students' Course Evaluations, Michael J. Drysdale

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several experts in the area of postsecondary student evaluations of courses have concluded that they are stable or reliable measures as well as being measures that provide ways of making valid inferences regarding teacher effectiveness. Often these experts have offered these conclusions without supporting evidence. Surprisingly, a thorough review of the literature revealed very few reported test-retest reliability studies of course evaluations and the results from these studies are contradictory. In the area of validity, the conclusions offered by scholars who conducted meta-analyses of mutlisection course studies are inconsistent. This leads to the following two research questions:

1. What is …

Rock Properties And Internal Structure Of The San Andreas Fault Near ~ 3 Km Depth In The Safod Borehole Based On Meso- To Micro-Scale Analyses Of Phase Iii Whole Rock Core, Kelly Keighley Bradbury, James P. Evans

Geosciences Presentations

We examine the relationships between rock properties and structure within ~ 41 m of PHASE III whole-rock core collected from ~ 3 km depth along the SAF in the San Andreas Fault Observatory at Depth (SAFOD) borehole, near Parkfield, CA.

Statistical Analysis Of The Usu Lidar Data Set With Reference To Mesospheric Solar Response And Cooling Rate Calculation, With Analysis Of Statistical Issues Affecting The Regression Coefficients, Troy Alden Wynn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Though the least squares technique has many advantages, its possible limitations as applied in the atmospheric sciences have not yet been fully explored in the literature. The assumption that the atmosphere responds either in phase or out of phase to the solar input is ubiquitous. However, our analysis found this assumption to be incorrect. If not properly addressed, the possible consequences are bias in the linear trend coefficient and attenuation of the solar response coefficient.

Using USU Rayleigh lidar temperature data, we found a significant phase offset to the solar input in the temperatures that varies ±5 years depending on …

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 …

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 …

Learning-Based Fusion For Data Deduplication: A Robust And Automated Solution, Jared Dinerstein

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents two deduplication techniques that overcome the following critical and long-standing weaknesses of rule-based deduplication: (1) traditional rule-based deduplication requires significant manual tuning of the individual rules, including the selection of appropriate thresholds; (2) the accuracy of rule-based deduplication degrades when there are missing data values, significantly reducing the efficacy of the expert-defined deduplication rules.

The first technique is a novel rule-level match-score fusion algorithm that employs kernel-machine-based learning to discover the decision threshold for the overall system automatically. The second is a novel clue-level match-score fusion algorithm that addresses both Problem 1 and 2. This unique solution …

Novel Approaches To Image Segmentation Based On Neutrosophic Logic, Ming Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Neutrosophy studies the origin, nature, scope of neutralities, and their interactions with different ideational spectra. It is a new philosophy that extends fuzzy logic and is the basis of neutrosophic logic, neutrosophic probability, neutrosophic set theory, and neutrosophic statistics.

Because the world is full of indeterminacy, the imperfection of knowledge that a human receives/observes from the external world also causes imprecision. Neutrosophy introduces a new concept , which is the representation of indeterminacy. However, this theory is mostly discussed in physiology and mathematics. Thus, applications to prove this theory can solve real problems are needed.

Image segmentation is the first …