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Articles 361 - 390 of 7340
Full-Text Articles in Physical Sciences and Mathematics
Temperature Dependent Density Of States Models And Compiled Data For Radiation Induced Conductivity, Jodie Gillespie
Temperature Dependent Density Of States Models And Compiled Data For Radiation Induced Conductivity, Jodie Gillespie
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Radiation Induced Conductivity (RIC) is the change in conductivity of a material due to bombardment from incident high energy radiation. RIC has consistently been found to follow a standard power law relation, 𝜎𝑅𝐼𝐶(𝑇) = 𝑘𝑅𝐼𝐶(𝑇)Ḋ∆(𝑇), between conductivity, 𝜎𝑅𝐼𝐶 and adsorbed dose rate, Ḋ. 𝑘𝑅𝐼𝐶(𝑇) and ∆(𝑇) are material dependent parameters. Previous RIC models were developed in the 𝑇 → 0 limit. Now expanded models are developed in the low temperature limit (within a few 𝑘𝐵𝑇 of the effective Fermi level) by approximating the Fermi-Dirac equation within a …
River Response To Sediment Supply: The Sand Bed Case, Christina M. Leonard
River Response To Sediment Supply: The Sand Bed Case, Christina M. Leonard
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Effective management of in-channel and floodplain habitat requires an ability to forecast river response to changes in water and sediment supply. These changes may result from dam construction/decommissioning, changes in reservoir operations, or changes in grazing or forestry practices. If a change in water and sediment supply causes sediment to be delivered faster than the channel’s capacity to transport it, sediment will accumulate in the reach, leading to changes in channel form and increasing the potential for flooding. A decrease in sediment supply relative to transport capacity can lead to channel incision. The extent and timing of sediment accumulation or …
Design Of Environment Aware Planning Heuristics For Complex Navigation Objectives, Carter D. Bailey
Design Of Environment Aware Planning Heuristics For Complex Navigation Objectives, Carter D. Bailey
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A heuristic is the simplified approximations that helps guide a planner in deducing the best way to move forward. Heuristics are valued in many modern AI algorithms and decision-making architectures due to their ability to drastically reduce computation time. Particularly in robotics, path planning heuristics are widely leveraged to aid in navigation and exploration. As the robotic platform explores and navigates, information about the world can and should be used to augment and update the heuristic to guide solutions. Complex heuristics that can account for environmental factors, robot capabilities, and desired actions provide optimal results with little wasted exploration, but …
Relativistic, Continuum Drift-Kinetic Capability In The Nimrod Plasma Fluid Code, Tyler Markham
Relativistic, Continuum Drift-Kinetic Capability In The Nimrod Plasma Fluid Code, Tyler Markham
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A ”runaway” electron is an electron that, through a self-reinforcing process, accelerates to relativistic speeds. At multiple points during tokamak discharges, relativistic runaway electron (RE) beams can form. RE beams pose a serious risk in the form of severe damage to plasma facing components in ITER and future burning plasma reactors. Early RE studies used simplified geometric and transport models, but enabled feedback on the overall plasma evolution. This feedback is important for understanding the evolution of the RE current column. The work in this thesis is an important step toward self-consistently evolving an RE distribution in the plasma fluid …
Carbon Sinks And Sources In Great Salt Lake: Consequences Of Declining Lake Levels, Melissa Cobo Arias
Carbon Sinks And Sources In Great Salt Lake: Consequences Of Declining Lake Levels, Melissa Cobo Arias
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Globally, saline lakes are experiencing declining water level as a consequence of climate change, water diversions for human consumption, and management strategies that do not account for changing climate and drought conditions. Great Salt Lake (GSL) is a large saline lake in Utah, USA, and is, as most saline lakes, experiencing decreasing lake levels which may impact local carbon cycling. It is unknown how lakebed drying affects processes that control carbon sequestration and carbon emissions to the atmosphere. The goal of this research was to measure various biological processes that use, create, and transform carbon in GSL to understand the …
Power Approximations For Generalized Linear Mixed Models In R Using Steep Priors On Variance Components, Sydney Geisler
Power Approximations For Generalized Linear Mixed Models In R Using Steep Priors On Variance Components, Sydney Geisler
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
When designing an experiment, researchers often want to know how likely they are to detect statistically significant effects in the resulting data, i.e., they want to estimate their statistical power. The probability distribution method is a flexible way to do this, and it is currently implemented in the statistical software package SAS. This method requires a hypothetical data set (showing the magnitude of hypothesized effects) and constant values of variance components, which are critical elements of the statistical models used. The statistical software package R is increasingly popular, but the probability distribution method has not yet been implemented in R, …
Statistical Challenges And Methods For Missing And Imbalanced Data, Rose Adjei
Statistical Challenges And Methods For Missing And Imbalanced Data, Rose Adjei
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Missing data remains a prevalent issue in every area of research. The impact of missing data, if not carefully handled, can be detrimental to any statistical analysis. Some statistical challenges associated with missing data include, loss of information, reduced statistical power and non-generalizability of findings in a study. It is therefore crucial that researchers pay close and particular attention when dealing with missing data. This multi-paper dissertation provides insight into missing data across different fields of study and addresses some of the above mentioned challenges of missing data through simulation studies and application to real datasets. The first paper of …
Investigating Atmospheric Gravity Waves Using 3-Dimensional Spectral Analysis, Kenneth I. Zia
Investigating Atmospheric Gravity Waves Using 3-Dimensional Spectral Analysis, Kenneth I. Zia
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Atmospheric gravity waves (GW) are generated from the ground and go into the upper layers of the atmosphere where space begins. These waves have strong effects on the temperature and circulation of the Earth’s atmosphere. The temperature changes caused by these waves are observed through special cameras looking at light that the Earth’s atmosphere naturally emit at night. One of these cameras is placed at McMurdo Station, Antarctica where the long nights are used to see these waves longer than anywhere else. The images captured there are automatically analyzed to determine wave properties to better understand how often they are …
Old-Growth Forest Dynamics After Fire And Drought In The Sierra Nevada, California, Usa, Kendall M.L. Becker
Old-Growth Forest Dynamics After Fire And Drought In The Sierra Nevada, California, Usa, Kendall M.L. Becker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Understanding forest ecosystems is important because forests cover approximately one-third of Earth’s land area, store half of Earth’s carbon, shelter half of Earth’s species, and absorb a quarter of new anthropogenic carbon emissions, slowing climate change. This dissertation provides insight into future forest habitat, fuels, species composition, and structure by investigating what happens to snags, seedlings, and trees in an old-growth forest after a low- to moderate-severity fire.
Chapter II explores how low- to moderate-severity fire changes snag fall rates. Predicting how long snags will remain standing after fire is essential for managing habitat, understanding chemical cycling in forests, and …
Late Pleistocene Piedmont Records In The Grand Staircase Region, Southern Utah, Alexander K. Short
Late Pleistocene Piedmont Records In The Grand Staircase Region, Southern Utah, Alexander K. Short
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Today the climate in the southwestern United States is arid, characterized by desert landscapes and habitats, periods of drought, and arroyo streams that frequently fill with, and erode, through fine riverbed sediments. A series of cliffs and benches rising from the Grand Canyon to the southern plateaus of Utah, known as the Grand Staircase - home to Kodachrome Basin State Park, Bryce Canyon, are a classical example of this environment as we know it today. However, a record spanning the past 300 thousand years is preserved on the steps of the staircase indicating periods in the past where the climate …
Functional Characterization Of The Newly Discovered Type V Crispr-Cas Protein Cas12a2, Dylan J. Keiser
Functional Characterization Of The Newly Discovered Type V Crispr-Cas Protein Cas12a2, Dylan J. Keiser
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Similarly to people, bacteria are under the treat of infection by viruses. To circumvent these threats, bacteria evolve complex immune systems. Our understanding of some of these immune systems has led to many advancements in the field of Biotechnology including tools that made expressing proteins for study in a lab easier, tools that revolutionized the feasibility of gene editing, and tools that could change the way we think about viral diagnostics and cancer therapeutics. A certain type of immune system that bacteria use to fight virus is called a CRISPR system. Presented here is work to understand the function of …
Investigating The Use Of Quartz Luminescence And Rock-Color Alteration To Characterize Wildfire Exposure; Applied To The 2020 Mangum Fire, Kaibab Plateau, Arizona, April I. Phinney
Investigating The Use Of Quartz Luminescence And Rock-Color Alteration To Characterize Wildfire Exposure; Applied To The 2020 Mangum Fire, Kaibab Plateau, Arizona, April I. Phinney
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Wildfires appear to be increasing in size, severity, and frequency. Land managers need information on past wildfire behavior to make effective and adaptive land management plans. However, there are only a few techniques and data sources that provide information on past fire heating. This study aims to provide new methods to equip managers with a more robust understanding of historic and modern fire behavior. Fire behavior is assessed using novel methods that can assess soil and rock response to past wildfire heat exposure.
This study examined samples from the 2020 Mangum Fire, in northern Arizona. Sediment and rock were gathered …
Development Of In Situ Second-Order Nonlinear Optical Scatterings For Molecular Behaviors At Aerosol Surfaces, Yuqin Qian
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Aerosol particles are one of the most important components of the atmosphere. During the growth of aerosol particles, they directly or indirectly affect air quality, human health, and environmental chemistry. Therefore, understanding the chemical and physical properties of such particles is an important scientific, engineering, and medical issue. The growth of aerosol particles in the atmosphere is closely related to the chemical structure at its surface, as well as the heterogeneous reactions which take place at and below the particle’s surface. However, there is a lack of suitable surface-specific analytical techniques which directly measure the chemical structure of aerosol particle …
Normative Evaluations Of Resource Conditions: The Influence Of Visitor Characteristics And Implications For Recreation Management In Urban-Proximate Parks, Jordan E. Nesbitt
Normative Evaluations Of Resource Conditions: The Influence Of Visitor Characteristics And Implications For Recreation Management In Urban-Proximate Parks, Jordan E. Nesbitt
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Urban-proximate parks and protected areas provide a unique recreation landscape to individuals living in and near urban centers. They have been shown to provide similar recreation experiences to traditionally studied parks and protected areas such as National Parks, National Forests and Wilderness areas. This study takes place in a set of four urban-proximate parks in Orange County, California, USA. These parks are designated as urban-proximate because they are located within 100 miles of an urban center with 1 million or more people. Using norm theory, a well vetted social science theory, this work sought to identify thresholds of acceptability for …
Human Appropriation Of Net Primary Production Through Crops, Grazing, And Forestry In The U.S. From 1997 To 2012, Suman Paudel
Human Appropriation Of Net Primary Production Through Crops, Grazing, And Forestry In The U.S. From 1997 To 2012, Suman Paudel
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This dissertation conducts a county-level analysis of human appropriation of net primary production (HANPP) harvested from crops, timber and grazing in the conterminous United States in the years 1997, 2002, 2007 and 2012. This study consists of three manuscripts (Chapters 2, 3, and 4). The first study quantifies net primary production in US counties in 1997, 2002, 2007 and 2012. The detailed HANPP study conducted concludes that HANPP is a valuable footprint tool for analyzing land use intensity and agricultural ecosystems. The second manuscript shows how HANPP is an improved or modernized ecological footprint and is a sustainable indicator as …
Bifurcations And Hysteresis In The Dynamics Of Small Populations Of Spherical Magnets, Peter T. Haugen
Bifurcations And Hysteresis In The Dynamics Of Small Populations Of Spherical Magnets, Peter T. Haugen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
If you heat up some kinds of metals and then cool them down next to a magnet, they will be a magnet when they cool, but if they cool down away from a magnet, they will just be a lump of metal. This is an example of hysteresis and it’s very important for lots of technology. Another example of hysteresis might be a water tower pump that turns on when the tower is nearly empty and keeps going until the tower is nearly full. Whether or not the pump is on when the tower is half full depends on what …
Pleistocene Deposits Of Lower Wahweap Creek And Its Tributaries, Southern Utah, Noah Slade
Pleistocene Deposits Of Lower Wahweap Creek And Its Tributaries, Southern Utah, Noah Slade
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The famous landscapes of the Colorado Plateau have been created over millions of years, primarily by erosive forces of wind and water. Interruptions in the long-term erosion of the landscape occur when streams gain more sediment than they can transport, which causes deposition along channels and floodplains. The resulting sequences of terrace deposits are used by geologists to study when and how river systems have evolved.
Mammoth bones were recently discovered in stream deposits along Wahweap Creek, a tributary of the Colorado River in southern Utah. Previous work indicates that the deposits pre-date the last ice age, making it one …
Investigations Of Prokaryotic Defense Systems, Hannah Domgaard
Investigations Of Prokaryotic Defense Systems, Hannah Domgaard
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Bacteria are constantly threatened with infection by mobile genetic elements (MGE) such as bacteriophage and plasmids. Bacteriophage and plasmids require the bacteria's cellular infrastructure to replicate their genomes. Rampant replication can lead to cell death which is one reason why bacteria have developed a diverse array of immune systems to prevent or limit infection. This thesis studies three types of bacterial immune systems, type IV-A CRISPR-Cas (Clustered Regularly Interspaced Short Palindromic Repeat –CRISPR associated), type V-A2 CRISPR-Cas systems, and Wadjet systems.
The type IV-A system lies adjacent to a dinG-like helicase gene. Research has shown that this system can target …
Portal: Portal Widget For Remote Target Acquisition And Control In Immersive Virtual Environments, Donguyn Han, Donghoon Kim, Isaac Cho
Portal: Portal Widget For Remote Target Acquisition And Control In Immersive Virtual Environments, Donguyn Han, Donghoon Kim, Isaac Cho
Computer Science Student Research
This paper introduces PORTAL (POrtal widget for Remote Target Acquisition and controL) that allows the user to interact with out-of-reach objects in a virtual environment. We describe the PORTAL interaction technique for placing a portal widget and interacting with target objects through the portal. We conduct two formal user studies to evaluate PORTAL for selection and manipulation functionalities. The results show PORTAL supports participants to interact with remote objects successfully and precisely. Following that, we discuss its potential and limitations, and future works.
Inertial Motion On The Earth's Spheroidal Surface, Boyd F. Edwards, Cade Pankey, John M. Edwards
Inertial Motion On The Earth's Spheroidal Surface, Boyd F. Edwards, Cade Pankey, John M. Edwards
All Physics Faculty Publications
As seen by an observer in the rotating frame, the earth’s small spheroidal deformations neutralize the centrifugal force, leaving only the smaller Coriolis force to govern the “inertial” motion of objects that move on its surface, assumed smooth and frictionless. Previous studies of inertial motion employ weakly spheroidal equations of motion that ignore the influence of the centrifugal force and yet treat the earth as a sphere. The latitude dependence of these equations renders them strongly nonlinear. We derive and justify these equations and use them to identify, classify, name, describe, and illustrate all possible classes of inertial motion, including …
Utah Growing Water Smart: The Water-Land Use Integration Guidebook, Kelly Kopp, Joanna Endter-Wada
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 1st edition of the Utah Growing Water Smart curriculum guidebook was prepared for the inaugural Utah workshop focused on Wasatch Front communities and held at the Wheeler Historical Farm in Murray, Utah on November 15-17, 2022. This …
Round Robin Tests Of Electron Irradiated Polymers Via Pulsed Electroacoustic Measurements, Zachary Gibson, J. R. Dennison, Virginie Griseri
Round Robin Tests Of Electron Irradiated Polymers Via Pulsed Electroacoustic Measurements, Zachary Gibson, J. R. Dennison, Virginie Griseri
Physics Student Research
Charge accumulation and migration can be studied using the pulsed electroacoustic (PEA) method to directly measure internal charge distributions in dielectric materials. This study aims to compare measurements using PEA systems constructed in labs at Utah State University and Université Paul Sabatier to establish confidence in comparing PEA results between different PEA systems. While there is good agreement in data measured for pristine samples with DC bias applied and no charge embedded, there are discrepancies in the data when measuring irradiated samples with embedded charge. The overall characteristics of charge distributions measured with both systems is clearly the same, but …
Symplectic Reduction Along A Submanifold, Peter Crooks, Maxence Mayrand
Symplectic Reduction Along A Submanifold, Peter Crooks, Maxence Mayrand
Mathematics and Statistics Faculty Publications
We introduce the process of symplectic reduction along a submanifold as a uniform approach to taking quotients in symplectic geometry. This construction holds in the categories of smooth manifolds, complex analytic spaces, and complex algebraic varieties, and has an interpretation in terms of derived stacks in shifted symplectic geometry. It also encompasses Marsden-Weinstein-Meyer reduction, Mikami-Weinstein reduction, the pre-images of Poisson transversals under moment maps, symplectic cutting, symplectic implosion, and the Ginzburg-Kazhdan construction of Moore-Tachikawa varieties in topological quantum field theory. A key feature of our construction is a concrete and systematic association of a Hamiltonian G-space 𝔐𝐺,𝑆 to …
Pausing While Programming: Insights From Keystroke Analysis, Raj Shrestha, Juho Leinonen, Albina Zavgorodniaia, Arto Hellas, John M. Edwards
Pausing While Programming: Insights From Keystroke Analysis, Raj Shrestha, Juho Leinonen, Albina Zavgorodniaia, Arto Hellas, John M. Edwards
Computer Science Student Research
Pauses in typing are generally considered to indicate cognitive processing and so are of interest in educational contexts. While much prior work has looked at typing behavior of Computer Science students, this paper presents results of a study specifically on the pausing behavior of students in Introductory Computer Programming. We investigate the frequency of pauses of different lengths, what last actions students take before pausing, and whether there is a correlation between pause length and performance in the course. We find evidence that frequency of pauses of all lengths is negatively correlated with performance, and that, while some keystrokes initiate …
Structural And Functional Studies Of Mtr4 And The Tramp Rna Surveillance Complex, Sean Johnson
Structural And Functional Studies Of Mtr4 And The Tramp Rna Surveillance Complex, Sean Johnson
Funded Research Records
No abstract provided.
Applying Expansive Framing To An Integrated Mathematics-Computer Science Unit, Kimberly Evagelatos Beck, Jessica F. Shumway
Applying Expansive Framing To An Integrated Mathematics-Computer Science Unit, Kimberly Evagelatos Beck, Jessica F. Shumway
Publications
In this research report for the National Council of Teachers of Mathematics 2022 Research Conference, we discuss the theory of Expansive Framing and its application to an interdisciplinary mathematics-computer science curricular unit.
An Assessment Of The Location Of The Bears Ears National Monument Cultural Center, Jordan W. Smith, Eunjung Yang, Anna B. Miller
An Assessment Of The Location Of The Bears Ears National Monument Cultural Center, Jordan W. Smith, Eunjung Yang, Anna B. Miller
Environment and Society Faculty Publications
A cultural center at Bears Ears National Monument, if well planned, could serve as an anchor destination through which visitors could learn about, experience, and appreciate the cultures, histories, and landscapes that define southeastern Utah. A cultural center also holds the potential to bolster the regional economy, by signaling a long-term investment in the sustainability of the region’s outdoor recreation and tourism industry. Our intent with this analysis is to establish a foundational understanding of potential locations for a cultural center. We develop and analyze a set of cultural, environmental, and economic metrics that can be used to shape ongoing …
Leveraging The "Large" In Large Lecture Statistics Classes, Kady Schneiter, Kimberleigh Felix Hadfield, Jenny Lee Clements
Leveraging The "Large" In Large Lecture Statistics Classes, Kady Schneiter, Kimberleigh Felix Hadfield, Jenny Lee Clements
Mathematics and Statistics Faculty Publications
Being a teacher or a student in a class with a large enrollment can be intimidating. Often, teachers view comforts that are common to small classes as unattainable in a larger class, including knowing students’ names, using active learning, employing group work, and creating group discussion. Students in large classes may find that the class size leads to isolation. At Utah State University, we offer introductory statistics classes for various audiences using a large lecture format. The authors have collectively led these large lectures dozens of times and found that, despite its shortcomings, the large lecture format can be an …
Editorial: Mammalian Responses To Climate Change: From Organisms To Communities, Johan T. Du Toit, Robyn S. Hetem, M. Denise Dearing
Editorial: Mammalian Responses To Climate Change: From Organisms To Communities, Johan T. Du Toit, Robyn S. Hetem, M. Denise Dearing
Wildland Resources Faculty Publications
Mammals have displayed spectacular evolutionary success ever since an asteroid impact caused the Cretaceous-Tertiary extinction event ~66 million years ago, when the non-avian dinosaurs disappeared. Now another mass extinction event is underway because of another major planetary disturbance, but this time it is directly caused by just one over-achieving species among all those mammals: Homo sapiens.
Pulsed Electroacoustic Measurements Of Polymers Irradiated With Low Energy Monoenergetic Electrons, Zachary Gibson, Jr Dennison
Pulsed Electroacoustic Measurements Of Polymers Irradiated With Low Energy Monoenergetic Electrons, Zachary Gibson, Jr Dennison
Physics Student Research
Understanding the dynamics and accumulation of embedded charge in dielectric materials is paramount for many applications from HVDC power transmission to spacecraft charging. The pulsed electroacoustic (PEA) method allows for nondestructive measurements of embedded charge distributions in dielectrics. The spatial resolution of PEA measurements are typically ~10 μm. However, some of the most deleterious spacecraft charging events result from electron fluxes with 10 keV to 50 keV energies, resulting in electron ranges of 1's to 10's of μm. Due to the resolution of the PEA method and the superposition of the interfacial charge with the deposited charge distribution, it is …