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Links Between Eruptive Styles, Magmatic Evolution, And Morphology Of Shield Volcanoes: Snake River Plain, Idaho, Katelyn J. Barton, Michelle Hurst May 2020

Links Between Eruptive Styles, Magmatic Evolution, And Morphology Of Shield Volcanoes: Snake River Plain, Idaho, Katelyn J. Barton, Michelle Hurst

Utah Space Grant Consortium

Despite their similar ages and geographic locations, two low-shield volcanoes on the eastern Snake River Plain, Idaho, Kimama Butte (87 ka) and Rocky Butte (95 ka), have strikingly different profiles. In this study, these two volcanoes are examined to determine the connections between chemical composition, intensive parameters, eruption style, and topographic features of basaltic shield volcanoes. Because lava temperature, magma viscosity, and chemical composition overlap at the two volcanoes, they are probably not important controls on the differences in morphology. The main difference at the two shields, aside from general vent morphology, is the presence of late-stage, phenocryst-rich, high viscosity …


Applying Real-World Learning Through Amusement Parks To Help Teach The Upcoming Changes To Utah Core Standard, Phil Lundgreen, Amanda Otterstrom May 2020

Applying Real-World Learning Through Amusement Parks To Help Teach The Upcoming Changes To Utah Core Standard, Phil Lundgreen, Amanda Otterstrom

Utah Space Grant Consortium

To assist educators in satisfying the Science with Engineering Education (SEEd) Standards the Utah State University (USU) Physics Department has developed a curriculum centered around USU Physics Day at Lagoon.

With an upcoming change to Utah's core standards and a shift to more hands-on learning styles, the use of real-world learning offered by amusement park applications is analyzed in its ability to satisfy the Utah State Bureau of Education’s (USBE) SEEd standards. Amusement park learning allows educators a vehicle to capture students’ attention in the classroom by discussing science principles in a fun and exciting manner with a promise of …


Lunar Mining: Designing A Robust Robotic Mining System, Ted Goodell, James Ehlers, Rian Simpson, Tina Hayward, Ali Almiskeen, Logan Peterson, Joshua Miraglia, Alexander Charters, Palmer Clegg, Chandler Millar, Emerson Labon, Jonathan Warner, Matthew Cohen, Evan Cleveland, Jackson Dean, Todd Renner, Sergio Nunez, Pramit Chalise, Arthur Steur, Jake Erickson, Kenny Ho May 2020

Lunar Mining: Designing A Robust Robotic Mining System, Ted Goodell, James Ehlers, Rian Simpson, Tina Hayward, Ali Almiskeen, Logan Peterson, Joshua Miraglia, Alexander Charters, Palmer Clegg, Chandler Millar, Emerson Labon, Jonathan Warner, Matthew Cohen, Evan Cleveland, Jackson Dean, Todd Renner, Sergio Nunez, Pramit Chalise, Arthur Steur, Jake Erickson, Kenny Ho

Utah Space Grant Consortium

The annual NASA Robotic Mining Challenge: Lunabotics tasks teams with building robots capable of traversing and mining simulated Lunar terrain. The competition goal is to utilize automation and sensing alongside mechanical systems to harvest icy regolith (gravel) from beneath the satellite’s surface.

This year, Utah Student Robotics sought to improve upon the design from last year. The 2019-2020 rover is based on proven NASA concepts, such as the RASSOR 2.0 digging drum, and the Rocker-Bogie mobility platform.


Private Land, Public Trust: Strategic Conservation Planning For Public Wildlife On Private Lands Through The Usfws Partners For Fish And Wildlife Program, Clint Wirick May 2020

Private Land, Public Trust: Strategic Conservation Planning For Public Wildlife On Private Lands Through The Usfws Partners For Fish And Wildlife Program, Clint Wirick

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

Law requires federal agencies to develop long-term strategic plans. Strategic plans define goals, objectives, and performance measures defining how the agencies and programs will reach their stated goals. U.S. Fish and Wildlife Service’s Partners for Fish and Wildlife (PFW) develops strategic plans every five years. Each individual state develops a plan for their respective state. Those state plans are compiled for the region and become part of Regional Comprehensive Strategic Plan. The current strategic plan expires in 2021. States will begin the strategic planning process in 2020. In Utah, PFW staff will also begin developing a strategic plan for the …


Impact Of Parasitic Drag On A Family Of Optimal Lift Distributions, Austin J. Stewart May 2020

Impact Of Parasitic Drag On A Family Of Optimal Lift Distributions, Austin J. Stewart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Minimizing drag is a variational problem, and several minimum induced drag solutions have been found using different design constraints. The elliptic lift distribution is commonly used to minimize induced drag, but is only the optimal solution under one set of design constraints. Non-elliptic lift distributions are able to reduce induced drag, when compared to the elliptic lift distribution, by increasing the wingspan while maintaining a consistent wing–structure weight. However, these non-elliptic lift distributions are only optimal if the effects of viscous drag are neglected. In this study, numerical tools are used to estimate the total drag on rectangular wings that …


Big Data Management For Secured Smart Healthcare System: A Machine Learning Framework, Abrar Zahin May 2020

Big Data Management For Secured Smart Healthcare System: A Machine Learning Framework, Abrar Zahin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Human action recognition and monitoring are a significant part of a smart healthcare system, which allows us to remotely monitor the behavior of patients or elderly persons to record their daily activities and to ensure safety. Ubiquitous smart wearable sensors are becoming convenient for generating and transmitting those healthcare data for further processing. Interpretation of such huge amount of data requires advanced learning systems where most important information can be extracted and analyzed. For example, current classification algorithms are not robust enough to differentiate among numerous variations of human actions due to the lack of sufficient processed samples. Thus, one …


Nanotextural And Nanochemical Constraints On The Role Of Heat In The Development Of Crystalline-Hosted, Silica-Rich Fault Mirrors In The Wasatch Fault Damage Zone, Utah, Usa, Leah M. Houser May 2020

Nanotextural And Nanochemical Constraints On The Role Of Heat In The Development Of Crystalline-Hosted, Silica-Rich Fault Mirrors In The Wasatch Fault Damage Zone, Utah, Usa, Leah M. Houser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Earthquakes occur on faults, or rock that has experienced displacement at depth. Experimental work on a range of rock types reveals that >90% of earthquake energy on fault surfaces is given off as heat. Heat weakens rock and promotes earthquake rupture propagation. Thin (<0.5mm), high-gloss, "polished", light-reflective exposed fault surfaces are called fault mirrors (FMs). Fault mirrors may record rapid thermal, textural, and chemical changes that occur during an earthquake event.

The Wasatch Mountains are a N-S trending mountain range in Northern Utah that are the backdrop for Salt Lake City, Provo, Ogden, and Brigham City. This mountain range is currently built by the active Wasatch fault, and includes the exposed Wasatch fault damage zone. Many segments of the Wasatch fault are overdue for a potentially catastrophic …


Predicting The Impact Of Weather On Rural Travel Times Using Now-Cast Weather Forecast Data, Manish Meshram May 2020

Predicting The Impact Of Weather On Rural Travel Times Using Now-Cast Weather Forecast Data, Manish Meshram

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the states which record extreme weather conditions and high snow in winters, the travel time to drive between cities can get highly affected due to these bad weather conditions. The present solutions to tackle this problem are largely flow or time related and do not take weather conditions into account while making the predictions about travel time. Also these solutions can mostly be used for real time travel and not the future travel. In addition to that, the studies that have been done in this space are mostly for urban travel times but most parts of the interstate highways …


Hardware Accelerator For Star Centroiding, Nazmus Sakib May 2020

Hardware Accelerator For Star Centroiding, Nazmus Sakib

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since the dawn of civilization mankind has gazed upon the night sky and looked for directions. In this modern age, the stars have proved to be a reliable reference point for navigation in space. From small-satellites for gathering weather data to inter-planetary missions like Cassini Orbiter, figuring out the location of a spacecraft has been done successfully by taking images of star filed visible from the spacecraft, processing and analyzing the image to find the stars and then finding out from a star catalog which part of the sky the patterns of the visible stars best matches. But a lot …


Teaching Distributed Application Design Using Drones, Cameron Frandsen May 2020

Teaching Distributed Application Design Using Drones, Cameron Frandsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis provides a new platform that instructors can use to create a learning environment for students to learn how to design and implement distributed applications. One possible way to use the platform uses milestones to test the student’s understanding of different concepts. Milestones contain pretests that students can use to test their code. Each milestone focuses on a different concept, including interprocess communication, reliability, and security. A monitor process can be created by the students to provide away for the instructor to see how well the students are learning the concepts by using a monitor process. The platform gives …


Applications Of Machine Learning In High-Frequency Trade Direction Classification, Jared E. Hansen May 2020

Applications Of Machine Learning In High-Frequency Trade Direction Classification, Jared E. Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The correct assignment of trades as buyer-initiated or seller-initiated is paramount in many quantitative finance studies. Simple decision rule methods have been used for signing trades since many data sets available to researchers do not include the sign of each trade executed. By utilizing these decision rule methods, as well as engineering new variables from available data, we have demonstrated that machine learning models outperform prior methods for accurately signing trades as buys and sells, achieving state-of-the-art results. The best model developed was 4.5 percentage points more accurate than older methods when predicting onto unseen data. Since finance and economics …


“What Makes ‘Em Tick?” The Impact Of Parenting Style And Parent-Initiated Motivational Climate On Student Athletes’ Motivation Orientation In The Context Of Intercollegiate Athletics, Logan Kateryna Lyons May 2020

“What Makes ‘Em Tick?” The Impact Of Parenting Style And Parent-Initiated Motivational Climate On Student Athletes’ Motivation Orientation In The Context Of Intercollegiate Athletics, Logan Kateryna Lyons

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Motivation has become a widely studied construct in intercollegiate athletics, as coaches and administrators have sought to maximize the socioemotional and performance aspects of athletic competition. While researchers acknowledge parents as having an important role in the socialization of motivation, research in this area has largely focused on sport-specific parenting practices, failing to account for the broader components of global parenting style that may influence parent-initiated motivational climates, and subsequently the motivational profiles exhibited by developing student athletes. The present study was designed to investigate the relationship among global parenting style, parent-created motivational climate, and student-athlete motivation within the context …


How Student Perceptions Of The Online Learning Environment And Student Motivation Predict Persistence, Completion, And Retention In Developmental Mathematics Courses, Samuel K. Gedeborg May 2020

How Student Perceptions Of The Online Learning Environment And Student Motivation Predict Persistence, Completion, And Retention In Developmental Mathematics Courses, Samuel K. Gedeborg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Online developmental mathematics courses have high dropout rates. The focus of this study is to improve understanding of how students’ perceptions of the online learning environment and student motivation from course design predict student drop out. This understanding will benefit faculty and institutions on student support for online developmental mathematics students.

The study included 330 undergraduate students enrolled in online developmental mathematics courses during the Fall 2018 semester at eight public universities and colleges in the Utah State Higher Education (USHE) system. Participants completed a survey with questions measuring their perceptions of the learning environment. They also completed a survey …


'Lmshapemaker': Utilizing The 'Rmapshaper' R Package To Modify Shapefiles For Use In Linked Micromap Plots, Braden D. Probst May 2020

'Lmshapemaker': Utilizing The 'Rmapshaper' R Package To Modify Shapefiles For Use In Linked Micromap Plots, Braden D. Probst

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In order to effectively create map-based visualizations, some map modifications need to be conducted to ensure the map is readable and interpretable. There are several issues that need to be addressed to achieve this. The boundaries of a country may be overly complex which is particularly true with coastal areas of countries. Regions may be small and not seen in the final plot, as is the case with many capital cities in the world’s countries such as Washington D.C. and the Federal District of Mexico City. In other countries, regions may geographically lie far away from the rest of the …


System-Level Analysis Of Autonomous Uav Landing Sensitivities In Gps-Denied Environments, Terran R. Gerratt May 2020

System-Level Analysis Of Autonomous Uav Landing Sensitivities In Gps-Denied Environments, Terran R. Gerratt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper presents an analysis of the navigation accuracy of an fixed-wing Unmanned Aerial Vehicle (UAV) landing on a aircraft carrier. The UAV is equipped with typical sensors used in landing scenarios. Data from the Office of Naval Research is used to accurately capture the behavior of the aircraft carrier. Through simulation, the position and orientation of both the UAV and carrier are estimated. The quality of the UAV’s sensors are varied to determine the sensitivity of these estimates to sensor accuracy. The system’s sensitivity to GPS signals and visual markers on the carrier is also analyzed. These results allow …


The Marshmallow Lab: A Project-Based Approach To Understanding Functional Responses, Melissa Pulley May 2020

The Marshmallow Lab: A Project-Based Approach To Understanding Functional Responses, Melissa Pulley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper presents a three-part lesson plan to improve student’s understanding of Holling’s type II functional response model. This model describes the interaction between a predator and how much it is able to consume given a constant number of prey. According to the model, while increased availability of prey allows predators to consume portionately more prey for low values, after some number of prey, predators will only be able to capture a limited number of prey even as the prey continues to increase. This phenomenon is known as saturation. Holling first develop this important ecological theory through his “disc experiment” …


Materials Design For High-Performance Organic Redox Flow Batteries And Electrocatalytic Carbon Dioxide And Nitrogen Reduction, Bo Hu May 2020

Materials Design For High-Performance Organic Redox Flow Batteries And Electrocatalytic Carbon Dioxide And Nitrogen Reduction, Bo Hu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nowadays, the utilization of renewable energy resources such as solar and wind energy has been realized to be a sustainable and environmentally benign strategy to alleviate the world’s severe dependency on traditional fossil fuels, and thus enables the environmental recovery and sustainable development of the economy. The massive commercialization of solar and wind energy raises the demands for advanced energy storage technologies, among which the redox flow battery has been recognized as a promising solution due to it is low cost, safe, environmentally benign, and easy to be scaled up. All vanadium redox flow battery stands for the most important …


Model-Based Properties Of Earth's Protective Shield: Relating Ut-Based Dependencies Of The Open/Closed Boundary, Cutoff Latitude, And L-Shell Parameter With Polar Cap Absorption Events, David A. Smith May 2020

Model-Based Properties Of Earth's Protective Shield: Relating Ut-Based Dependencies Of The Open/Closed Boundary, Cutoff Latitude, And L-Shell Parameter With Polar Cap Absorption Events, David A. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High frequency radio continues to be an important communications medium. For example, commercial airlines use high frequency radios as their primary communications mode during transpolar crossings. It has been estimated that over 7000 transpolar flights occur each year. Unfortunately, during geomagnetic storms high frequency communications can become unreliable, especially near Earth's Polar Regions.

Space weather forecasters are burdened with the responsibility of predicting how radio signals might be affected during geomagnetic storms and passing that important information on to commercial airlines, allowing them to adjust flight plans accordingly. Such adjustments can be costly, but are necessary to ensure safety of …


Family Development And The Marital Relationship As A Developmental Process, J. Scott Crapo May 2020

Family Development And The Marital Relationship As A Developmental Process, J. Scott Crapo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Despite the commonly held idea that families develop, there is not a theory in common use within the family science field that is developed specifically for the study of the development of the family. Family development theory, developed in the post-World War II era, was used previously, but an inability to be adapted to contemporary families and a lack of scientific utility have kept it from use. Additionally, research on how families develop has not considered how relationships may develop over time.

In this dissertation, I seek to address these holes in the family studies field. I do this over …


Retention Of Women In Computer Science: Why Women Persist In Their Computer Science Majors, Katarina Pantic May 2020

Retention Of Women In Computer Science: Why Women Persist In Their Computer Science Majors, Katarina Pantic

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Retention of women through graduation in Computer Science (CS) majors is one of the biggest challenges for CS education. Most research in this area focuses on factors influencing attrition rather than why and how women remain committed. The goal of this research study is to understand retention from the perspective of women who persisted in their CS major. Using the theoretical lens of legitimate peripheral participation in communities of practice, I designed and conducted a study that involved focus groups, interviews, journey maps, and experience sampling methods. I found that retention of women in this study was influenced by four …


Linear Operators That Preserve Two Genera Of A Graph, Leroy B. Beasley, Kyung-Tae Kang, Seok-Zun Song Apr 2020

Linear Operators That Preserve Two Genera Of A Graph, Leroy B. Beasley, Kyung-Tae Kang, Seok-Zun Song

Mathematics and Statistics Faculty Publications

If a graph can be embedded in a smooth orientable surface of genus g without edge crossings and can not be embedded on one of genus g − 1 without edge crossings, then we say that the graph has genus g. We consider a mapping on the set of graphs with m vertices into itself. The mapping is called a linear operator if it preserves a union of graphs and it also preserves the empty graph. On the set of graphs with m vertices, we consider and investigate those linear operators which map graphs of genus g to graphs of …


Clustering And Classifying Geophysical Rock Properties Of The San Andreas Fault, Jared Bryan Apr 2020

Clustering And Classifying Geophysical Rock Properties Of The San Andreas Fault, Jared Bryan

Physics Capstone Projects

Borehole geophysical data provide important in situ observations for identifying and characterizing geologic and structural features in the subsurface. We perform an unsupervised classification of geophysical logs from the Sand Andreas Fault Observatory at Depth (SAFOD) borehole in order to define intervals of distinct geophysical properties. We focus on borehole geophysical data collected during Phase 3 drilling operations from 3.0-3.3 km measured depth, which encompasses the active trace of the San Andreas Fault. We use dimensionality reduction to increase the interpretability of the retrieved clusters, and we compare the performance of distance- and density-based clustering techniques. K-means clustering produces highly …


Optical Relaxation Of Defects In Kapton Caused By Irradiation, Ashlan Keeler Swainston Apr 2020

Optical Relaxation Of Defects In Kapton Caused By Irradiation, Ashlan Keeler Swainston

Physics Capstone Projects

Radiation can create atomic-scale defect states in polymers, leading to changes in their optical, electrical and mechanical properties. Recent studies of polymers have shown that these defect states are sensitive to oxygen or air exposure. It is believed that air cause the number of defect states to decrease and the polymers to revert to their original states. However, the time scale of this regression is not known. This experiment quantified the time that it takes one polymer to recover and the extent of said recovery; polymide (PI). In order to study the regression, optical transmission data were taken using a …


Co Sense And Release Flavonols: Progress Toward The Development Of An Analyte Replacement Photocorm For Use In Living Cells, Marina Popova, Tatiana Soboleva, Abby D. Benninghoff, Lisa M. Berreau Apr 2020

Co Sense And Release Flavonols: Progress Toward The Development Of An Analyte Replacement Photocorm For Use In Living Cells, Marina Popova, Tatiana Soboleva, Abby D. Benninghoff, Lisa M. Berreau

Chemistry and Biochemistry Faculty Publications

Carbon monoxide (CO) is a signaling molecule in humans. Prior research suggests that therapeutic levels of CO can have beneficial effects in treating a variety of physiological and pathological conditions. To facilitate understanding of the role of CO in biology, molecules that enable fluorescence detection of CO in living systems have emerged as an important class of chemical tools. A key unmet challenge in this field is the development of fluorescent analyte replacement probes that replenish the CO that is consumed during detection. Herein, we report the first examples of CO sense and release molecules that involve combining a common …


Understanding Noether’S Theorem By Visualizing The Lagrangian, Seth Moser Apr 2020

Understanding Noether’S Theorem By Visualizing The Lagrangian, Seth Moser

Physics Capstone Projects

By approaching Lagrangian mechanics from a graphical perspective the implications of Noether’s Theorem can be made easier to understand. Plotting the Lagrangian for classical single particle systems for one coordinate onto a position-velocity phase space along with the corresponding equations of motion can demonstrate how a system is invariant under continuous transforms in that coordinate. This invariance can be shown to be associated with a quantity in the system that’s conserved via Noether’s Theorem. The relationship between the symmetry of the system and conserved quantities can then be extended to fields. Invariance in this case is extended to include invariance …


Caterpillars On A Phytochemical Landscape: The Case Of Alfalfa And The Melissa Blue Butterfly, Matthew L. Forister, Su'ad A. Yoon, Casey S. Philbin, Craig D. Dodson, Bret Hart, Joshua G. Harrison, Oren Shelef, James A. Fordyce, Zachary H. Marion, Chris C. Nice, Lora A. Richards, C. Alex Buerkle, Zach Gompert Apr 2020

Caterpillars On A Phytochemical Landscape: The Case Of Alfalfa And The Melissa Blue Butterfly, Matthew L. Forister, Su'ad A. Yoon, Casey S. Philbin, Craig D. Dodson, Bret Hart, Joshua G. Harrison, Oren Shelef, James A. Fordyce, Zachary H. Marion, Chris C. Nice, Lora A. Richards, C. Alex Buerkle, Zach Gompert

Biology Faculty Publications

Modern metabolomic approaches that generate more comprehensive phytochemical profiles than were previously available are providing new opportunities for understanding plant‐animal interactions. Specifically, we can characterize the phytochemical landscape by asking how a larger number of individual compounds affect herbivores and how compounds covary among plants. Here we use the recent colonization of alfalfa (Medicago sativa) by the Melissa blue butterfly (Lycaeides melissa) to investigate the effects of indivdiual compounds and suites of covarying phytochemicals on caterpillar performance. We find that survival, development time, and adult weight are all associated with variation in nutrition and toxicity, including …


Library Services: Impact Analysis Spring 2018 To Fall 2018, Amanda M. Hagman, Lindsay Ozburn, Hayden Hoopes, Erik Dickamore, Bradford R. Cole, Mitchell Colver Apr 2020

Library Services: Impact Analysis Spring 2018 To Fall 2018, Amanda M. Hagman, Lindsay Ozburn, Hayden Hoopes, Erik Dickamore, Bradford R. Cole, Mitchell Colver

Publications

Libraries are an essential element of learning on university campuses. The content housed within libraries supports academic exploration and growth. Physically, libraries are designed to provide access to materials and spaces that facilitate learning. This report explored the impact of student library resource use on student persistence to the next term.

Students' library resource use was captured with EZ Proxy log-ins and library material check-outs. Students who had a record of using library resources were compared to similar students who did not have a record of library resource use. They were compared using prediction-based propensity score matching. Students who used …


Modeling The Alkaline Hydrolysis Of Diaryl Sulfate Diesters: A Mechanistic Study, Klaudia Szeler, Nicholas H. Williams, Alvan C. Hengge, Shina C. Kamerlin Apr 2020

Modeling The Alkaline Hydrolysis Of Diaryl Sulfate Diesters: A Mechanistic Study, Klaudia Szeler, Nicholas H. Williams, Alvan C. Hengge, Shina C. Kamerlin

Chemistry and Biochemistry Faculty Publications

Phosphate and sulfate esters have important roles in regulating cellular processes. However, while there has been substantial experimental and computational investigation of the mechanisms and the transition states involved in phosphate ester hydrolysis, there is far less work on sulfate ester hydrolysis. Here, we report a detailed computational study of the alkaline hydrolysis of diaryl sulfate diesters, using different DFT functionals as well as mixed implicit/explicit solvation with varying numbers of explicit water molecules. We consider the impact of the computational model on computed linear free-energy relationships (LFER) and the nature of the transition states (TS) involved. We obtain good …


Evidence For Horizontal Blocking And Reflection Of A Small‐Scale Gravity Wave In The Mesosphere, Neal R. Criddle, Pierre-Dominique Pautet, Tao Yuan, C. Heale, J. Snively, Yucheng Zhao, Michael J. Taylor Apr 2020

Evidence For Horizontal Blocking And Reflection Of A Small‐Scale Gravity Wave In The Mesosphere, Neal R. Criddle, Pierre-Dominique Pautet, Tao Yuan, C. Heale, J. Snively, Yucheng Zhao, Michael J. Taylor

All Physics Faculty Publications

The variations of the horizontal phase velocity of an internal gravity wave, generated by wave “blocking” or “reflection” due to an inhomogeneous wind field, have been predicted theoretically and numerically investigated but had yet to be captured experimentally. In this paper, through a collaborative observation campaign using a sodium (Na) Temperature/Wind lidar and a collocated Advanced Mesospheric Temperature Mapper (AMTM) at Utah State University (USU), we report the first potential evidence of such a unique gravity wave process. The study shows that a small‐scale wave, captured by the AMTM, with initial observed horizontal phase velocity of 37 ± 5 m/s …


Determing The Chaotic Nature Of Periodic Orbits, Bo Johnson Apr 2020

Determing The Chaotic Nature Of Periodic Orbits, Bo Johnson

Physics Capstone Projects

The determination of the long-term behavior of periodic orbits is considered. Different numerical techniques, including the Lyapunov Exponent, the Smaller Alignment Index, and the Generalized Alignment Index are used. Because of the discontinuous nature of the system under consideration, these methods are found to be insufficient and a more simplistic approach is utilized. The simplistic approach determines long-term behavior up to 500 periods of an orbit. It is found that in-phase periodic modes result in the largest amount of stable modes. Future work will look at the common characteristics of the in-phase modes to better understand why they are more …