Digital Commons Network^™

Using Smart Foodscapes To Enhance The Sustainability Of Western Rangelands, Juan J. Villalba

Funded Research Records

No abstract provided.

Introduction To Classical Field Theory, Charles G. Torre

All Complete Monographs

This is an introduction to classical field theory. Topics treated include: Klein-Gordon field, electromagnetic field, scalar electrodynamics, Dirac field, Yang-Mills field, gravitational field, Noether theorems relating symmetries and conservation laws, spontaneous symmetry breaking, Lagrangian and Hamiltonian formalisms.

Co-Designing Ai-Based Orchestration Tools To Support Dynamic Transitions: Design Narratives Through Conjecture Mapping, Luettamae Lawrence, Boyuan Guo, Kexin Yang, Vanessa Echeverria, Zimmy Kang, Vikrant Bathala, Christina Li

Instructional Technology and Learning Sciences Faculty Publications

Dynamically transitioning between individual and collaborative learning has been hypothesized to have positive effects, such as providing the optimal learning mode based on students’ needs. There are, however, challenges in orchestrating these transitions in real-time while managing a classroom of students. AI-based orchestration tools have the potential to alleviate some of the orchestration load for teachers. In this study, we describe a sequence of three design sessions with teachers where we refine prototypes of an orchestration tool to support dynamic transitions. We leverage design narratives and conjecture mapping for the design of our novel orchestration tool. Our contributions include the …

Collaborative Research: Surface-Specific Aerosol Chemistry: Direct Observations, Kinetics, And Environmental Impact, Yi Rao

Funded Research Records

No abstract provided.

Utah Women And Stem: A 2022 Update, Rebecca Winkel, Susan R. Madsen

Marketing and Strategy Faculty Publications

According to the U.S. Bureau of Labor Statistics (BLS), careers in STEM (Science, Technology, Engineering, and Math) are expanding faster and pay better than other careers.¹ The median annual wage for STEM occupations in 2020 was nearly $90,000, more than double the median annual wage for all occupations (about $42,000).² STEM opportunities abound in Utah, one of the top 10 states for tech job growth, net tech employment concentration, and net tech employment job gains in 2020.³ In fact, Salt Lake City is ranked the second-best city in the country for professional opportunities in STEM.⁴

Yet, …

Normal-Mode Oscillations For The Circular And Dipolar States Of A Filled Hexagonal Magnetic Dipole Cluster, Peter T. Haugen, Andrew D. P. Smith, Boyd F. Edwards

All Physics Faculty Publications

We analyze the rotational dynamics of six magnetic dipoles of identical strength at the vertices of a regular hexagon with a variable-strength dipole in the center. The seven dipoles spin freely about fixed axes that are perpendicular to the plane of the hexagon, with their dipole moments directed parallel to the plane. Equilibrium dipole orientations are calculated as a function of the relative strength of the central dipole. Small-amplitude perturbations about these equilibrium states are calculated in the absence of friction and are compared with analytical results in the limit of zero and infinite central dipole strength. Normal modes and …

An Evaluation Of The Effect Of The Oxycontin Reformulation On Unintentional Fatal And Nonfatal Overdose, Daniel C. Beachler, Kelsey Hall, Renu Garg, Geetanjoli Banerjee, Ling Li, Luke Boulanger, Huseyin Yuce, Alexander M. Walker

Applied Sciences, Technology and Education Faculty Publications

Objectives:

OxyContin was reformulated with a polyethylene oxide matrix in August 2010 to reduce the potential for intravenous abuse and for abuse by insufflation. The objective of this study was to evaluate the impact of OxyContin's reformulation on overdose (OD) risk for individuals dispensed OxyContin in comparison to those dispensed other opioids under regular care.

Materials and Methods:

Three national insurance databases with National Death Index linkage identified OD in individuals with any dispensing of OxyContin or a primary comparator opioid (extended release morphine, transdermal fentanyl, or methadone) between July 2008 through September 2015. A difference-in-differences design was used to …

Model Averaging In Agriculture And Natural Resources: What Is It? When Is It Useful? When Is It A Distraction?, Philip M. Dixon

Conference on Applied Statistics in Agriculture and Natural Resources

I use two examples to illustrate three methods for model averaging: using AIC weights, using BIC weights, and fully Bayesian analyses. The first example is a capture-recapture study that estimates the population size by averaging over 4 models for capture probabilities. The second is an analysis of a study of logging impacts on Curculionid weevils using a before-after-control-impact (BACI) study design. The estimated impact is averaged over 4 ecologically relevant models.

Both examples demonstrate the sensitivity of model weights, or posterior model probabilities, to the choice of prior model probabilities and prior distributions for parameters. The model averaged estimates and …

A Robust Clustering Method Using Compositional Data Restrictions: Studying Wood Properties In The Reforestation Of Portugal, Pamela M. Chiroque-Solano, Guido A. Moreira

Conference on Applied Statistics in Agriculture and Natural Resources

Classification of multivariate observations while preserving the data’s natural restriction is a challenge. Special properties such as identifiability, interpretability, and others need to be cared for to build a new approach. To avoid these complications, many transformation algorithms have been developed to use traditional models.In this context, the aim of this work is to propose a robust probabilistic distance algorithm to classify compositional data. Based on the probabilistic distance (PD) clustering approach, the proposal identifies clusters minimizing a joint distance function, JDF, which is part of a dissimilarity measure. This measure combines the PD clustering approach with the density of …

Random Regression For Modeling Semen Fertility In Hf Purebred And Crossbred Bulls Using A Bayesian Framework, Vrinda Ambike, R. Venkataramanan, S. M. K. Karthickeyan, K. G. Tirumurugaan, Kaustubh Bhave, M. Swaminathan

Conference on Applied Statistics in Agriculture and Natural Resources

Data on insemination records of Holstein Friesian (HF) purebred (n=45,497) and crossbred (n=58,497) collected from the BAIF Research Foundation were utilized. The conception rate was modeled as a binary trait, using linear repeatability models. Random regression models (RRM) were used to obtain the trajectory of variance components across age of the bulls. Legendre Polynomials up to order of fit of 4 were used for the random effects of additive genetic and permanent environmental effects. 200,000 Gibbs samples were generated with a burn-in of 20,000 and thinning interval of 50 using the THRGIBBS1F90 program. Heritability estimates were very low (0.1) in …

Principal Response Curve Analysis Of Arthropod Community Abundance Data With Sparse Subsets, Changjian Jiang, C. R. Brown, P. Asiimwe, Chen Meng, Adam W. Schapaugh

Conference on Applied Statistics in Agriculture and Natural Resources

Principal response curve (PRC) analysis was applied to an assessment of the ecological impact of the genetically-modified (GM), insect-resistant, cotton MON 88702 on predatory Hemiptera communities in the field. The field community was represented by ten taxa collected ten times across the season at six sites, in which individual taxa were not observed in at least 25% of the time (unique site x collection combinations). These complete absences and those nearly so, called sparse subsets of the data in this investigation, were the result of geoclimatic and seasonal variations, which are both independent of the treatment effect for which the …

Handling Non-Detects With Imputation In A Nested Design: A Simulation Study, Rose Adjei, John R. Stevens

Conference on Applied Statistics in Agriculture and Natural Resources

In this paper, a simulation study was conducted to assess whether it is ideal to address the issue of non-detects in data using a traditional substitution approach for non-detects, imputation, or a non-imputation based approach. Simulated data used were simple nested designs motivated by a real-life data in a study of bumble bee activity in a commercial cherry orchard by Kuivila et al. (2021). The simulated data were generated at different thresholds or censoring levels and at different effect sizes. For each simulated data, seven popular existing techniques to handle non-detects were applied: (i) Zero substitution, (ii) Substitution with half …

Overview Of Optimal Experimental Design And A Survey Of Its Expanse In Application To Agricultural Studies, Stephen J. Walsh

Conference on Applied Statistics in Agriculture and Natural Resources

Optimal Design of Experiments is currently recognized as the modern dominant approach to planning experiments in industrial engineering and manufacturing applications. This approach to design has gained traction among practitioners in the last two decades on two-fronts: 1) optimal designs are the result of a complicated optimization calculation and recent advances in both computing efficiency and algorithms have enabled this approach in real time for practitioners, and 2) such designs are now popular because they allow the researcher to ‘design for the experiment’ by working constraints, cost, number of experiments, and the model of the intended post-hoc data analysis into …

To The Moon And Mars And Back To The Archives: Working With Modern Space Collections At The University Of Arizona Libraries, Molly Stothert-Maurer, Lisa E. Duncan

Journal of Western Archives

With a long history at the University of Arizona with excellence in the lunar and planetary sciences, the University of Arizona Libraries Special Collections has increased its collecting of the History of Science and Technology. These large, modern space collections pose unique challenges and require specific needs to be addressed in order for the collections to be stored, processed and made available for access. It is essential for archivists working with these collections to ask their donors the right questions and learn the limitations and restrictions that often come with acquiring modern space collections. Archives around the country have started …

Introduction, Jason Olsen

Journal on Empowering Teaching Excellence

Access the online Pressbooks version of this introduction here.

An introduction to the Spring 2022 issue of the Journal on Empowering Teaching Excellence.

Transforming Curriculum: A Process For Implementing Problem-Based Learning In A College-Level Course, Morgan Robertson, Marla K. Robertson

Journal on Empowering Teaching Excellence

Access the online Pressbooks version of this article here.

Transforming curriculum by implementing Problem-Based Learning (PBL) in the college-level classroom helps students internalize the concepts of a course, improve their critical and reflective thinking skills, learn to problem-solve using questioning, and ultimately construct a better understanding of course concepts in a personally relevant way. This article introduces a process for implementing PBL in a college-level course. Each of the four main ideas in PBL, motivation, collaboration, reflection, and facilitation, are addressed with a particular focus on the role of the educator in designing and implementing PBL in the classroom. An …

Draw A Picture Of Yourself Learning Math: What Pre-Service Teachers’ Self-Portraits Illustrate About Their Complex Relationships With Mathematics, Samantha Sommers, Michelle Unigarro, Danielle Vantassel, Claudia M. Bertolone-Smith, Alison Puliatte

Journal on Empowering Teaching Excellence

Access the online Pressbooks version of this article here.

The purpose of this study was to examine factors that may influence pre-service teachers’ relationships with mathematics. Elementary pre-service teachers who were enrolled in a mathematics methods course (n = 52) wrote a letter to math and drew a picture of themselves learning math. The self-portraits were analyzed by a team of undergraduate student researchers and teacher educators to identify themes related to the types of emotions, experiences, and situations displayed. The results of the self-portrait analysis indicated a higher percentage of negative emotions as compared to positive and neutral …

Pre-Service Elementary School Teachers’ Perceptions Of Themselves As Learners Of Mathematics And Science, Diana L. Moss, Rachel Wilson, Danielle Divis

Journal on Empowering Teaching Excellence

Access the online Pressbooks version of this article here.

This study investigated how prospective elementary teachers view themselves as learners of mathematics and science during their last year in a teacher preparation program at an American university. Using drawing and reflections as the method for collecting data, prospective teachers were prompted to draw themselves and reflect on learning mathematics and draw themselves and reflect on learning science prior to and after their mathematics and science methods courses. Drawings (n = 147) were coded according to the presence or absence of several themes including physical objects, teachers, students, and environment. …

Full Issue: Journal On Empowering Teaching Excellence, Volume 6, Issue 1, Spring 2022

Journal on Empowering Teaching Excellence

The full-length 2022 Special Issue (Volume 5, Issue 3) of the Journal on Empowering Teaching Excellence

Access the online Pressbooks version (with downloadable EPUB format) here.

The Spring 2022 issue begins with research that explores the perceptions of pre-service teachers relative to learning mathematics and science, with suggestions for how findings can impact curriculum and further research. The focus on pre-service teachers continues with research into their sense of self-efficacy with instructional technologies and whether specific techniques increase comfort level with technologies. Next, researchers explore the products that Generation Z students value most in their learning of a second language, …

Quantifying Impacts Of Grazing And Poor Land Management Strategies On Erosion Through A Semi-Automated Change Detection Workflow In Ka’Amola, Molokai, L. Kalai Ellis, Richard A. Gill

Utah Space Grant Consortium

A challenge faced by those working in a system plagued by non-native vegetation invasion and disturbance from ungulates is the ability to collect landscape-level information about land cover change and the mass movement of soils associated pulsed rainfall events. Our goal was to conduct high-precision change detection of land cover and surface features during a two-year period that included several mass sediment flux events associated with tropical storms. We present here preliminary results of the development and testing of a rule set based classification algorithm used to classify imagery from 2019 and 2021 of a single watershed in Molokai to …

Biophysical Factors Control Invasive Grass Hot Spots In The Mojave Desert, Tanner C. Smith, Tara B. B. Bishop, Michael C. Duniway, Ryan R. Jensen, Richard A. Gill

Utah Space Grant Consortium

Invasive annual grasses are a nuisance in the American Southwest through promotion of the grass-fire cycle. Annual grasses such as Bromus rubens, Bromus tectorum, Schismus barbatus, and Schismus arabicus have invaded the Mojave Desert and increased fire occurrence, thus it is important to identify and characterize the areas where persistent invasion has occurred and subsequently fire risk is increased by understanding the distribution of these invasive grasses. Here we use a remote sensing framework to map persistent and productive populations of invasive annual grass, called hot spots, in the entire Mojave Desert ecoregion over 12 years, identify …

Aerodynamic Effects Of Phase Offset Between Synchronized Propellers In Hover, Nathan Welker, Daniel Maynes

Utah Space Grant Consortium

Emerging advances in electric-propulsion technology are enabling aircraft to use distributed electric propulsion (DEP) to increase efficiency and maneuverability. The implementation of DEP effectively decreases the spacing between propellers, introducing complex aerodynamic interactions that are not well understood. This study presents the use of stereoscopic particle image velocimetry (SPIV) to obtain 3D velocity measurements of the flow fields of phase locked and synchronized propellers at close proximity in a side-by-side configuration. These experiments were performed to explore the aerodynamic effect of phase offset between the propellers. It was found that while the propeller interactions cause an induced upwash and a …

Progress Report: Covid-19 Hotspot Detection In University Campus Settings, Garrett Duncan, William F. Christensen, Camilla Handley

Utah Space Grant Consortium

The COVID-19 pandemic caused a lot of disruption in the academic world. Many schools and universities shut down entirely and transitioned to online learning. As BYU made the transition back to in-person learning, the administration needed to know if there was in-class transmission happening on campus in order to regulate restrictions and keep students and faculty safe. Using demographic information about the students, we built an XGBoost model that produces an estimated probability of testing positive for each student. We incorporated engineered variables from the demographic information as well. We evaluated model fit using metrics such as AUC. Using a …

Internal Wave Generation By Multiple Peak Topographies, Natsha 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 of multiple peaks on a single topography has on internal wave generation is explored. Initial results begin to show that multiple ridges create two parallel IW beams with smaller IWs between them compared to the single beam created by a one ridge topography. Kinetic energy is also tightly clustered at lower wavenumbers in Fourier …

Exploration Of An Electrochemical Sensor For Continuous Monitoring Of Estradiol In Application To Fertility Tracking, Julia S. Dominesey, Shad J. Roundy

Utah Space Grant Consortium

Estradiol is one of three estrogens, the primary female sex hormone; it fluctuates diurnally, and monthly, dictating the menstrual cycle. We developed a bench-top electrochemical sensor to detect estradiol with the intention of future realization into an implantable, continuously sampling sensor to be used as an aid for fertility health. The electrochemical sensor is comprised of a three electrode system which utilizes a gold working electrode, platinum counter electrode, and Ag/AgCl reference electrode to perform cyclic voltammetry. A monolayer of estradiol aptamers and mercaptohexanethiol coat the working electrode surface. The monolayer was exposed to 10ng/mL, 100n/mL and 1,000ng/mL of estradiol. …

Refill Friction Stir Spot Welding As An Alternative Jointing Method For Wing Spar Structures, Paul Blackhurst, Yuri Hovanski, Andrew Curtis

Utah Space Grant Consortium

Refill Friction Stir Spot Welding (RFSSW) is an emerging solid state joining process for thin sheet aluminum. Many researchers are developing RFSSW process parameters, thus enabling the use of RFSSW in many industries. Some work within this development has been on the application of RFSSW to wing spar stringer and skin joining. This is thanks to the RFSSW process being capable of welding the high-strength aluminum alloys used for wing spar construction. Traditionally wing spar joining has been achieved using rivets. This newer method has the potential to improve the strength, reduce the weight, and lower the cost of wing …

Acoustic Analysis Of The Delta Iv Heavy Launch Vehicle, Griffin Houston, Grant W. Hart, Kent L. Gee

Utah Space Grant Consortium

The Delta IV Heavy is an orbital heavy class launch vehicle that has been in operation since 2004. In this study, the overall sound power level and other acoustic properties of the Delta IV Heavy launch vehicle will be calculated and analyzed. Five data acquisition systems with a wide frequency bandwidth were placed in a far-field arc around a 2021 launch. Using a weighted mean to compare results across stations, a maximum overall sound pressure level (OASPL) of 140 dB and an average maximum polar directivity angle of 69 deg were calculated. An overall sound power level of 198 dB …

Development Of Optical Systems For In-Situ Measurements Of High-Temperature Combustion Plumes, Cara Frischkorn, Stephen A. Whitmore

Utah Space Grant Consortium

Results from proof-of-concept tests using fiber-optic cables inserted into the combustion port of a lab-scale hybrid rocket system are reported. The fiber optic cables transmit optical signals to miniature spectrometers and allow in-situ optical characterization of the combustion plume properties including flame temperature and combustion plume species. Multiple firings with burn durations varying from 5 to 25 seconds were performed. The fiber optic sensors survived all tests and resulting rocket performance data were correlated with in-situ optical spectra data. When the optical measurements were adjusted to account for the spectrometer transfer function and the resulting spectra were curve-fit to Planck's …

Ionosphere/Thermosphere Dynamics Obtained From Cosmic Satellite Observations, Layne Pedersen, Ludger Scherliess

Utah Space Grant Consortium

The morphology and climatology of thermospheric neutral winds play an important role in ionospheric and thermospheric dynamics. Thermospheric neutral winds effect temporal and spatial variations of ionospheric plasma which plays an important role F-region dynamics. However, direct observations of thermospheric neutral winds are historically limited both temporally and spatially [1]. For example, interferometric methods for measuring thermospheric winds are restricted to nighttime observations and cloudless conditions and are limited to relatively few locations. Space-based observations made by cross-track measurements from accelerometers as well as onboard interferometers and spectrometers provide valuable information of thermospheric winds but coverage is inconsistent over a …

Launch Vehicle Acoustics Research, Taggart Durrant, Carson Cunningham, Kent Gee, Grant Hart, Mark Anderson, Logan Mathews, Griffin Houston, Michael Bassett, Matthew Yancey, Samuel Olausson

Utah Space Grant Consortium

No abstract provided.