Physical Sciences and Mathematics Commons^™

A Mechanistic Examination Of Interspecific Competition Between Wild And Domestic Herbivores, Courtney Check

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Large herbivores, such as mule deer and cattle have similar life histories and likely compete for resources. However, quantifying the extent to which these species compete and the specific resources they compete for has proved challenging. My research examines if cattle influence deer abundance and behavior due to competition for forage, competition for shade, and/or by affecting the predation risk of deer. Using a grid of autonomous trail cameras, I was able to determine if cattle abundance influences local deer abundance in relation to specific resources and habitat features. Using GPS data from collared deer, I was also able to …

The Time-Dependent Ionospheric Model Using A Tec-Driven Servo: An Investigation Of The Capabilities And Limitations, Jenny Rebecca Whiteley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ionosphere is a region of the atmosphere with a high density of electrons. These electrons affect the behavior of any electromagnetic wave that passes through the ionosphere. Communication and geolocation systems, such as traditional radio and Global Positioning Systems, depend on emitted electromagnetic signals being picked up by a receiver. The presence of the ionosphere affects the behavior of the signal and the quality of the service. Hence, the interactions between electromagnetic waves and the ionosphere provide a major motivation to understand, research, and successfully model and predict the ionosphere and its physical phenomena. This study focused on determining …

Proxy Voting Coordination Mechanisms: Determining How Agents Should Coordinate In A Continuous Preference Space, Michael D. Hegerhorst

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Illness, injury, and other impediments are common occurrences of everyday life. Such impediments prevent or deter voters from participating in important parts of the voting process, especially deliberation, bargaining, and the voting itself. Without participation, the results of the vote may change. There is a need to provide a system in which voters are still able to participate in important voting processes to ensure their vote is represented. We explore ‘proxy voting,’ a system in which voters are able to select another individual, or proxy, to vote on their behalf. By choosing a good proxy, a voter can still …

Comparing Commonly Used Aquatic Habitat Modeling Methods For Native Fishes, Eryn K. Turney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water resources are managed for a variety of human needs, including agriculture, industrial and municipal consumption, hydropower generation, and recreation. There has been a recent push to incorporate habitat needs of aquatic wildlife into water management models alongside these other uses, particularly as competition for limited water resources in a changing climate has reduced instream flow and contributed to declining native fish populations. Habitat models are used to estimate species distributions and differentiate between suitable and unsuitable habitat based on variables important to a given species, but are not usually incorporated into water management models. Because there are many ways …

Volatile Cycling And Metasomatism In Flat-Slab Subduction Zones Of The Central Andes, Coleman Hiett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Flat-slab subduction, where an oceanic plate subducts horizontally below a continental margin for hundreds of kilometers, is an enigmatic but prevalent tectonic configuration in which chemical cycling and alteration of the continental plate is poorly constrained. Geochemical investigations in regions of modern and ancient flat-slab subduction in the Central Andes afford an opportunity to study this process. Certain elements naturally occur with varying number of neutrons in their nuclei (isotopes), and measurements of isotope ratios within geologic materials inform on chemical sources and geologic processes. This research leverages stable isotope analyses and other geochemical tools to investigate volatiles and other …

Accuracy Vs. Energy: An Assessment Of Bee Object Inference In Videos From On-Hive Video Loggers With Yolov3, Yolov4-Tiny, And Yolov7-Tiny, Vladimir A. Kulyukin, Aleksey V. Kulyukin

Computer Science Faculty and Staff Publications

A continuing trend in precision apiculture is to use computer vision methods to quantify characteristics of bee traffic in managed colonies at the hive's entrance. Since traffic at the hive's entrance is a contributing factor to the hive's productivity and health, we assessed the potential of three open-source convolutional network models, YOLOv3, YOLOv4-tiny, and YOLOv7-tiny, to quantify omnidirectional traffic in videos from on-hive video loggers on regular, unmodified one- and two-super Langstroth hives and compared their accuracies, energy efficacies, and operational energy footprints. We trained and tested the models with a 70/30 split on a dataset of 23,173 flying bees …

C···O And Si···O Tetrel Bonds: Substituent Effects And Transfer Of The Sif3 Group, Zhihao Niu, Qiaozhuo Wu, Qingzhong Li, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The tetrel bond (TB) between 1,2-benzisothiazol-3-one-2-TF₃-1,1-dioxide (T = C, Si) and the O atom of pyridine-1-oxide (PO) and its derivatives (PO-X, X = H, NO₂, CN, F, CH₃, OH, OCH₃, NH₂, and Li) is examined by quantum chemical means. The Si···O TB is quite strong, with interaction energies approaching a maximum of nearly 70 kcal/mol, while the C···O TB is an order of magnitude weaker, with interaction energies between 2.0 and 2.6 kcal/mol. An electron-withdrawing substituent on the Lewis base weakens this TB, while an electron-donating group has the opposite …

Evaluation Of Bio-Friendly Formulations From Siderophore-Producing Fluorescent Pseudomonas As Biocontrol Agents For The Management Of Soil-Borne Fungi, Fusarium Oxysporum And Rhizoctonia Solani, Gaber Attia Abo-Zaid, Ahmed Salah Abdullah, Nadia Abdel-Mohsen Soliman, Ebaa Ebrahim El-Sharouny, Abdulaziz A. Al-Askar, Yiming Su, Ahmed Abdelkhalek, Soraya Abdel-Fattah Sabry

Civil and Environmental Engineering Faculty Publications

Secretion of siderophores by Pseudomonas aeruginosa F2 and P. fluorescens JY3 was evaluated on chrome azurol S (CAS) agar plates and their inhibitory effect was inspected against Fusarium oxysporum and Rhizoctonia solani. Production of siderophores as biocontrol agents from F2 and JY3 was accomplished in two optimized media. Afterward, cell-free supernatants of the bacterial cultures containing siderophores were used for the preparation of two bio-friendly formulations for the management of F. oxysporum and R. solani under greenhouse conditions. The investigated bacterial isolates, F2 and JY3, showed antagonistic activity in vitro against F. oxysporum and R. solani and produced siderophores …

Variability In Consumption And End Uses Of Water For Residential Users, Camilo J. Bastidas Pacheco, Jeffery S. Horsburg, Attallah A. Nour

Research Briefs

Research Objective/Summary: In most large urban water systems in the US, the residential sector consumes the majority of total supplied fresh water. In a world plagued with increasing water scarcity and climate change stresses, understanding individual home water end-uses is vital to water management and conservation. We studied the end uses of water in residential homes, both indoor and outdoor to find patterns and variations in consumption over time. Results indicate a need for more efficient water fixtures, particularly toilets, and provide an opportunity to promote conservation behavior.

Assessing Downstream Aquatic Habitat Availability Relative To Headwater Reservoir Management In The Henrys Fork Snake River, Christina N. Morrisett, Robert W. Van Kirk, Sarah E. Null

Watershed Sciences Student Research

Reservoirs are sometimes managed to meet agricultural and other water demands, while also maintaining streamflow for aquatic species and ecosystems. In the Henrys Fork Snake River, Idaho (USA), irrigation-season management of a headwater reservoir is informed by a flow target in a management reach ~95 km downstream. The target is in place to meet irrigation demand and maintain aquatic habitat within the 11.4 km management reach and has undergone four flow target assignments from 1978 to 2021. Recent changes to irrigation-season management to maximize reservoir carryover warranted investigation into the flow target assignment. Thus, we created a streamflow-habitat model using …

Comparing Visitor Perceptions, Characteristics, And Support For Management Actions Before And During A Pilot Timed Entry System At Arches National Park, Zachary D. Miller, Amy Tendick, Caleb Meyer, David Pettebone, Bret Meldrum, Steve Lawson

Environment and Society Student Research

Over the past decade, many national park units in the United States broke visitation records. Arches National Park (UT, USA) is no exception. Between 2011 and 2021, visitation increased 74%. As part of considering management options to address the issues from sustained and concentrated visitation, Arches implemented a pilot timed entry system from 3 April to 3 October 2022. This article compares visitor perceptions, characteristics, and support for management actions before and during the pilot timed entry system using data from visitor intercept surveys. Findings suggest visitors experience quality improved across the park and on hiking trails during the pilot …

On Correspondences Between Feedforward Artificial Neural Networks On Finite Memory Automata And Classes Of Primitive Recursive Functions, Vladimir A. Kulyukin

Computer Science Faculty and Staff Publications

When realized on computational devices with finite quantities of memory, feedforward artificial neural networks and the functions they compute cease being abstract mathematical objects and turn into executable programs generating concrete computations. To differentiate between feedforward artificial neural networks and their functions as abstract mathematical objects and the realizations of these networks and functions on finite memory devices, we introduce the categories of general and actual computabilities and show that there exist correspondences, i.e., bijections, between functions computable by trained feedforward artificial neural networks on finite memory automata and classes of primitive recursive functions.

Upep Policy Brief #1: Utahns Support State Spending For Outdoor Recreation, Casey Trout

Utah People and Environment Poll (UPEP)

Utah is known as an outdoor recreation destination, with stunning landscapes ranging from high alpine mountains to red-rock deserts. In recent years, Utah’s Legislature has shown a commitment to investing in outdoor recreation. In 2017, the Legislature approved a 0.32% statewide lodging tax to fund Utah’s Outdoor Recreation Grant Program¹ and in 2022 approved a diversion of 1% of all sales taxes in the state to go to funding outdoor recreation infrastructure projects².

2023 Utah People & Environment Poll Descriptive Report, Jessica Schad, Sadie Braddock, Cole Lancaster

Utah People and Environment Poll (UPEP)

From March to May 2023, faculty and graduate students at Utah State University (USU) in the College of Humanities and Social Sciences (CHaSS) and in the department of Environment and Society started the Utah People and Environment Poll, or UPEP, to survey adult Utah residents about their perceptions on environmental issues of importance to the state.

Utah Growing Water Smart: The Water-Land Use Integration Guidebook, Kelly Kopp, Joanna Endter-Wada

Utah Growing Water Smart

The Utah Growing Water Smart workshops bring together teams of key community staff and water and land use planning decision makers to help build a more resilient and sustainable water future. The workshops use a range of public engagement, planning, communication, and policy implementation tools to help community teams realize their water efficiency, smart growth, watershed health, and water resiliency goals.

This 2nd edition of the Utah Growing Water Smart curriculum guidebook was prepared for the workshop focused on Northern Utah and held at Utah State University on June 6-8, 2023. This guidebook has four main sections: Planning and Goal …

Planning For A Gnarly Future: Reimagining Planning To Empower Your Community, Elizabeth Sodja

All Current Publications

The purpose of this document is to summarize key takeaways and resources from our 5-part online learning series featuring planning solutions to challenges facing Gateway and Natural Amenity Region (GNAR) communities in the west.

Evaluation Of Temperature-Index And Energy-Balance Snow Models For Hydrological Applications In Operational Water Supply Forecasts, Tian Gan, David G. Tarboton, Tseganeh Z. Gichamo

Civil and Environmental Engineering Faculty Publications

In the western United States, snow accumulation, storage, and ablation affect seasonal runoff. Thus, the prediction of snowmelt is essential to improve the reliability of water supply forecasts to guide water allocation and operational decisions. The current method used at the Colorado Basin River Forecast Center (CBRFC) couples the SNOW-17 temperature index snow model and the Sacramento Soil Moisture Accounting (SAC-SMA) runoff model in a lumped approach. Limitations in parameter transferability and calibration requirements for changing conditions with the temperature-index model motivated this research, in which new avenues were investigated to assess and prototype the application of an energy-balance snow …

Spectral Fits Of Brown Dwarfs: Discovering Trends Across The Spectral Type Sequence, Savanah Turner, Denise Stephens, Conner Scoresby

Utah Space Grant Consortium

Brown dwarfs are substellar objects that form like stars but never achieve the core temperatures and pressures needed to ignite hydrogen fusion. These "failed stars" have been shown to exhibit complex atmospheres similar to those of planets, making them useful analogs for exoplanets. As a brown dwarf cools over time, different cloud species condense or fall below the surface of the atmosphere, causing changes in the resulting spectrum of the object. Comparison of theoretical atmospheric models to real brown dwarf spectra can provide insight into the physical and chemical processes occurring in the atmosphere of the object. We have fit …

Comparing A 3-D Printed Hemispherical-Head And Rankine Body Probe Shapes For Very Low Speed Air Data Measurements, Stephen A. Whitmore, Zheng Qi C. Case

Utah Space Grant Consortium

This study investigates the feasibility of using Flush Air Data Sensing (FADS) System technology for air data measurements at the very low-airspeeds, where many Unmanned Aerial Vehicles (UAVs) operate. FADS is a non-intrusive alternative to pitot probes, where the vehicle nosecone, wing leading edge, or other aerodynamic surface is configured with multiple pressure-ports distributed along the windward surface. Although FADS technology has been used for a variety of high-speed aircraft, FADS has never been applied to very low-airspeed flight regimes. This study reports on wind tunnel tests of two 3-D printed shapes: 1) a cylindrical body with a hemispherical head, …

Continuous-Time Trajectory Estimation For Differentially Flat Systems, Jacob C. Johnson, Joshua G. Mangelson, Randal W. Beard

Utah Space Grant Consortium

Continuous-time estimation using splines on Lie groups has been gaining traction in the literature in recent years due to their ability to incorporate high-frequency sensor data without introducing new optimization parameters. However, evaluating time derivatives and Jacobians of Lie group splines is computationally expensive, limiting their use mainly to offline applications. Motivated by the trajectory planning literature, we develop a new estimation technique that leverages the differential flatness property of many dynamic systems to define the spline in the system's flat output space, which is often Euclidean, and show an example of its use with the unicycle dynamic model. We …

One-Dimensional Radial Turbomachinery Modeling, Chase Oliphant

Utah Space Grant Consortium

Centrifugal flow impellers are commonly used in a wide variety of industrial machines. Predicting the performance of these impellers over the entire operating range is key to the system development during the early design stages. The two element in series (TEIS) and two-zone model can be used to accurately predict impeller performance based on flow physics and empirical correlations. Correlations were made with linear regression on a database of 50 pumps and 75 impellers. These correlations were later found to only apply to designs that are similar to those in the database. This paper proposes a new method to generate …

A Preliminary Review And Discussion Of Metrics For Origami-Based Deployable Arrays, Katie Varela, Spencer P. Magleby

Utah Space Grant Consortium

When designing deployable structures, there are many things to consider that help the deployment method integrate with the system. Preliminary metrics are proposed to help rate the deployment systems to determine the best methods for each application. The top four metrics that apply to most space applications are mass, usable area, volume, and energy. Additional considerations that are less quantifiable are included for the value they contribute to the system. Trade-offs may be necessary for different applications.

Experimental Characterization Of Internal Wave Generation By Multiple Peak Topographies, Natasha Wilson, Julie Crockett

Utah Space Grant Consortium

Internal waves are generated in the oceans and atmosphere and play an important role in their energy budgets. The semidiurnal oscillation of the tides over topography in the oceans combined with the density stratification can create internal waves that radiate away from their source. The effect multiple peaks on a single topography has on internal wave generation is explored. Three and four topography peaks create three and four crests respectively in the internal wave beams. Five and six peak topographies generate internal wave beams characterized by two bounding crests and several smaller crests in the middle of the beam. In …

Development, Modeling And Performance Analysis Of An Electric Vtol Aircraft With Tiltable Rotors, Clayton Spencer, Samantha Burton, Tianyi He

Utah Space Grant Consortium

In this paper, the development and modeling of an electric Vertical-Take-Off-and Landing (eVTOL) aircraft with tiltable rotors. The front two rotors have tilting capability for transition flight from vertical take-off to forward-direction level flight. This paper focuses on the design and analysis of an eVTOL aircraft platform. The study includes layout and system architecture, the selections and optimization of components, such as electric motors, batteries, and controllers, as well as the integration of these components into the overall aircraft system. In addition, the dynamical model is derived as a nonlinear differential equation. Afterwards, a linearization-based model and Linear Parameter-Varying (LPV) …

Facilitation Of Deployable Antennas Using A Panel Structure Optimization Framework, Nathan Coleman

Utah Space Grant Consortium

Origami has become a popular method for beginning mechanical design due to its ability to stow compactly and deploy to a large area. One common origami pattern is the Flasher, which has a roughly circular shape and aspect ratio, centers around a polygon which can be grounded, and is easily extensible. Because of these advantages, the Flasher is a candidate for many deployable applications, including space-based optical telescopes, LiDaR telescopes, solar arrays, and reflectarray antennas. One of the primary difficulties when implementing the Flasher pattern is that it is not rigid-foldable and is subject to panel interference at high-degree vertices. …

Optimizing Nitrogen Use For Continuous Recycling In Closed Life Support Systems, Noah J. Langenfeld, Bruce Bugbee

Utah Space Grant Consortium

Nitrogen (N) is needed by plants in the highest amount among root-zone-derived nutrients. Closed life-support systems for space missions will rely on in-situ food production for long-term sustainability, but high resupply and N fixation costs necessitate N recycling to support human nutrition for extended mission durations. We studied combinations of four N forms [ammonium, nitrate, urea, and N-fixing bacteria (protein)] for their use as an optimal N source for lettuce (Lactuca sativa) grown in peat moss in two container sizes (1.7 L and 8 L). Plants grown with ammonium nitrate consistently had the highest mass. When ammonium, urea, or microbial …

Fabrication Of Metallic Far-Infrared Filters, Jared E. Payne, Joseph Eddy, Hunter R.J. Stevenson, Brad Ferguson, Ryan T. Beazer, Gregory N. Nielson, Stephen M. Shultz

Utah Space Grant Consortium

A far-infrared filter is fabricated by creating metallic squares on a dielectric substrate. This capacitive metallic filter is fabricated using direct write laser ablation consisting of a femtosecond laser in combination with a high numerical aperture objective. A representative capacitive filter is fabricated on soda-lime glass substrate with a period of 100 µm and separation width of 30 µm. A capacitive filter was also fabricated on a thin film polypropylene substrate with similar dimensions. The filter was tested and the frequency response is discussed.

Lasso (L1) Regularization For The Development Of Sparse Remote Sensing Models Of Water Quality, Anna C. Cardall, Riley C. Hales, Kaylee B. Tanner, Gustavious P. Williams, Kel N. Markert

Utah Space Grant Consortium

Remote sensing data (data contained in satellite imagery) are used extensively to monitor waterquality parameters such as clarity, temperature, and chlorophyll-a (chl-a). This is generally done bycollecting in situ data coincident with satellite data collections, then creating empirical water qualitymodels using approaches such as multi-linear regression or step-wise linear regression. Theseapproaches, which require modelers to select model parameters, may not be well-suited for opticallycomplex waters, where interference from suspended solids, dissolved organic matter, or otherconstituents may act as “confusers”. For these waters, it may be useful to include non-standard terms,which might not be considered using traditional methods. Recent machine learning …

Photodegradation Of Self-Immolating Polymers As A Potential Solution To Optical Scattering, Alex Gallion, Sydney Mcfarland, David Allred, Walter Paxton

Utah Space Grant Consortium

Starshades and other sensitive optical devices require dust mitigation techniques to protect their surfaces. We investigate coating these surfaces with a photodegradable polymer film that will vaporize when exposed to ultraviolet light. A series of experiments was conducted in which we studied this phenomenon in vacuum after applying a photo-depolymerizing coating. Poly (2-methyl, 1-pentene) sulfone is shown to degrade in vacuum when exposed to 172 nm UV light. Future studies will examine whether the coating can be used to remove dust contaminants from sensitive optical devices upon photoirradiation..

Measuring The Period Of Variable Stars In Ngc 188, Molly Christensen, Connor Smith, Christian Draper

Utah Space Grant Consortium

Galactic cluster NGC 188 is 1.93 kpc away located in the constellation Cepheus. This cluster is one of the oldest clusters that contain W UMa stars W UMa variables are a type of eclipsing binary butare unique because they share an envelope of materia laround two stars. According to Simbad there are 741 interacting binaries in NGC 188. 70 of these are eclipsing binaries. We chose NGC 188 because it is an ideal place to study the evolution of W UMa stars because it is one of the oldest galactic clusters with this type of star. Despite the overabundance of …