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An Argument For The Second Nuclear Era: Salvaging The Atomic Age In Response To Climate Change, Ian Sager

Honors Capstones

No abstract provided.

College Of Natural Sciences Newsletter, December 2021, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 2, Issue 12

Page 1 Dean's Message
Page 2 Awards & Recognition
Page 2 Media Coverage of CNS
Page 3 Media Coverage Cont.
Page 4 Science as Art Competition
Page 5 Open PRAIRIE Data
Page 5 Grants Awarded in CNS

Evaluating Deep-Learning Models For Debris-Covered Glacier Mapping, Zhiyuan Xie, Vijayan K. Asari, Umesh K. Haritashya

Electrical and Computer Engineering Faculty Publications

In recent decades, mountain glaciers have experienced the impact of climate change in the form of accelerated glacier retreat and other glacier-related hazards such as mass wasting and glacier lake outburst floods. Since there are wide-ranging societal consequences of glacier retreat and hazards, monitoring these glaciers as accurately and repeatedly as possible is important. However, the accurate glacier boundary, especially the debriscovered glacier (DCG) boundary, which is one of the primary inputs in many glacier analyses, remains a challenge even after many years of research using conventional remote sensing methods or machine-learning methods. The GlacierNet, a deep-learning-based approach, utilized the …

Image Data Analysis And Design Optimization Of The Snowball Chamber, Yujia Huang

Legacy Theses & Dissertations (2009 - 2024)

Dark Matter is the invisible massive particle that makes up over 26.8 percent of the mass-energy content of the universe. Weakly Interacting Massive Particles, or WIMPs, are one of the candidates of dark matter particles. Many scientists around the world are trying to figure out how to detect detect dark matter using either indirect search, direct production or direct detection experiments. However, due to the lack of evidence of finding WIMPs in direct detection experiments at a large mass scale, a call for investigating WIMPs at a lower mass range is attracting more attention.

Reliability Characterization Of A Low-K Dielectric Using Its Magnetoresistance As A Diagnostic Tool, Philip Alister Williams

Legacy Theses & Dissertations (2009 - 2024)

The introduction of low dielectric constant materials within the integrated circuit (IC) chip technology industry was a concerted effort to decrease the resistance-capacitance (RC) time delay inherent within the dielectric materials used as insulators. This stems from a demand for greater device density per IC chip and decreased feature sizes but is fast becoming a reliability issue. Concomitant with the demand for decreased feature sizes, also in adherence with Moore’s Law (which states that the number of devices on a die doubles every two years), is a reduction in device speed and performance due to device intra-level interconnection signal delays. …

Entropic Density Functional Theory : Entropic Inference And The Equilibrium State Of Inhomogeneous Fluids, Ahmad Yousefi

Legacy Theses & Dissertations (2009 - 2024)

A unified formulation of the density functional theory is constructed on the foundations of entropic inference in both the classical and the quantum regimes. The theory is introduced as an application of entropic inference for inhomogeneous fluids in thermal equilibrium. It is shown that entropic inference reproduces the variational principle of DFT when informationabout expected density of particles is imposed. In the classical regime, this process introduces a family of trial density-parametrized probability distributions, and consequently a trial entropy, from which the preferred one is found using the method of Maximum Entropy (MaxEnt). In the quantum regime, similarly, the process …

Plasma-Laser Wakefield Acceleration, Jonathan Babu

Physics

Many texts detailing the derivations and science of Wakefield Acceleration are aimed at graduate and doctorate level scholars, and these may seem intimidating to new physics students. This paper is meant to be an introduction to the nature of plasmas, lasers, laser-plasma interactions, and Laser Wakefield Acceleration (LWFA), with sources given where extra detail may be required. I recognize that this paper is not meant to be an all-encompassing review on the nature of the topics, as these topics are complex and subject of entire textbooks. Instead, I aim to provide an introduction to these topics to a college-level scholar …

Modeling Cherenkov Light Detection Timing For The Very Energetic Radiation Imaging Telescope Array System, Keilan Finn Ramirez

Physics

The Very Energetic Radiation Imaging Telescope Array System (VERITAS) is an array of four 12-meter telescopes which use the Imaging Atmospheric Cherenkov Technique to conduct high-energy gamma-ray astronomy. VERITAS detects magnitude and location information associated with Cherenkov light, and uses this information to indirectly observe gamma-rays through a software reconstruction process. VERITAS also records timing information corresponding to Cherenkov light detection, and this additional information could theoretically be incorporated into the reconstruction process to improve the accuracy of gamma-ray observations. The first step to including timing information is to understand when Cherenkov light detection would be expected from a known …

Swarming Oscillators With Time-Delayed Interactions, Nicholas S. Blum

Physics

We investigate the role of delay in the collective dynamics of particles that swarm in space and possess an internal oscillatory degree of freedom, called swarmalators. Swarmalators were introduced recently by O’Keeffe, Hong, and Strogatz in Nature Communications 8, 1504 (2017). The addition of a time delay into the system of swarmalators was motivated by the biology of early embryonic development. This delay leads to a rich phenomenology, which includes two new collective states, which we call "semi-static crystal" and "boiling". In the semi-static crystal state, all particles in a cluster undergo decaying radial oscillations completely in phase with one …

Optimizing Mixed Reality Simulation To Support Stem Graduate Teaching Assistants In Developing Student-Centered Pedagogical Skills, Constance Doty

Electronic Theses and Dissertations, 2020-2023

Physics graduate teaching assistants (GTA) often instruct student-centered lab and recitation sections at large universities, creating the opportunity to positively impact students. However, as STEM GTA professional development varies by institution and discipline, GTAs rarely receive feedback about their teaching. In K-12 teacher preparation, "microteaching", where a teacher teaches a lesson to peers acting as students, is used to provide feedback. Research has demonstrated benefits to microteaching in K-12 teacher and STEM GTA preparation, but practicing teachers find microteaching can lack authenticity. Recently, researchers have explored integrating technology, like simulation, in pedagogy training to provide a more authentic training experience. …

Development Of A Magnetic Confinement Attachment For Enhanced Signal In Handheld Laser Induced Breakdown Spectroscopy Soil Analysis, Alfred C. Anderson

Theses and Dissertations

Field techniques for characterizing low levels of heavy elements of less than 100 parts per million in soils tend to be unreliable because of the relatively weak signal of these elements and the large, variable background inherent to analyzing soils with minimal sample preparation. To enhance the detection and analysis capability of a handheld laser-induced breakdown spectroscopy (LIBS) instrument, this work investigates the effects of a unique magnetic confinement apparatus on signal intensities, focusing on five iron lines as well as those from actinides in 11 soil samples. The proposed magnetic confinement apparatus achieved over 0.8 T but did not …

Characterization Of Infrared Metasurface Optics With An Optical Scatterometer, Matthew R. Miller

Theses and Dissertations

An optical scatterometer is used to characterize the infrared scatter of a dielectric metasurface cylindrical lens and two variants of that design. The design uses dielectric nanopillars to create the parabolic phase delay required for lensing; the variants change the length of the nanopillars from the design length of 4 microns to 0.9 and 5.2 microns. Scatter measurements were made at the design wavelength of 4 microns, and at 3.39 and 5 microns. These measurements showed wide-angle scatter greater than that measured for a conventional refractive optic, and that these metasurfaces perform their optical function best at the design wavelength …

Investigation Of Added Mass Of Heeled 2-D Sections In A Seaway Using The Patch Method In Heave, Roll, And Sway Motions, Adam N. Bacon

LSU New Orleans Theses and Dissertations

This thesis analyzes the effects of the angle of heel and beam-to-draft ratio on the sectional added mass of primitive cross-sectional shapes in regular harmonic waves in the frequency domain using 2-D boundary element method for uncoupled heave, sway, and roll motion. This 2-D boundary element method uses the patch method developed by Söding (1993b) [4] to compute the added mass of asymmetric geometry. The angles of heel used varied from 0 to 90 degrees in 5-degree intervals, while the beam-to-draft ratios varied from B/T = 0.5 to B/T = 3.0 in half increments. Triangles, rectangles, and rectangles with rounded …

Interplay Between The Lattice And Spin Degrees Of Freedom In Magnetoelectric And Magnetic Materials, Temuujin Bayaraa

Graduate Theses and Dissertations

This dissertation contains several investigations on the cross-coupling between structural and spin degrees of freedom in multiferroic and ferrimagnetic compounds by means of first-principles calculations and ab-initio-based Monte-Carlo simulations. We start with the reviews of magnetoelectricity, ferrimagnetism, strain engineering, followed by a brief introduction to first-principles computational methods, magnetic effective Hamiltonians, and other techniques that are utilized here. The results section of the dissertation can be divided into two parts. The first half focuses on magnetoelectric effects arising from different sources, while the second half is about the ferrimagnetic nature of materials. In the first part, we examine the epitaxial …

Investigation And Discovery Of Novel Transition Metal Cysteamine Systems With Halogens From The First Principles Calculations, Noura Dawas Alkhaldi

Physics Dissertations - Archive

Cu-cysteamine (Cu-Cy) is a material that has the cysteamine bonded with Cu. It is a molecular photosensitizer which can be activated by visible, ultraviolet light, and X-rays to generate reactive oxygen species (ROS). Cu-Cy has been used in various applications such as solid-state lighting, radiation detection, and as treatment of both shallow and deep cancers. Hence, it is important to study the stability, electronic and optical properties of Cu-Cy as well as finding other possible cysteamine systems. The first principle theoretical investigations of novel transition metal cysteamine systems with halogens are performed by density functional theory. In the first part …

Orbital Evolution Studies And Radio Searches Of Extra-Solar Moons, Marialis Rosario-Franco

Physics Dissertations - Archive

Exoplanetary research has undergone a great deal of development and growth. Achievements in theoretical studies and detection techniques have led to the discovery of 4,000+ exoplanets in ~3, 000 planetary systems to date. Despite this great success, and though candidates have been proposed, the confirmation of the first exomoon is yet to be accomplished. Understanding the constraints under which extrasolar moons form around exoplanets can provide insight into the overall formation of the system, the host planet’s habitability, and could even aid the process of drawing out the best observational candidates for exomoon searches. This work entails the use of …

Investigation Of Optical And Structural Properties Of Gesn Heterostructures, Oluwatobi Gabriel Olorunsola

Graduate Theses and Dissertations

Silicon (Si)-based optoelectronics have gained traction due to its primed versatility at developing light-based technologies. Si, however, features indirect bandgap characteristics and suffers relegated optical properties compared to its III-V counterparts. III-Vs have also been hybridized to Si platforms but the resulting technologies are expensive and incompatible with standard complementary-metal-oxide-semiconductor processes. Germanium (Ge), on the other hand, have been engineered to behave like direct bandgap material through tensile strain interventions but are well short of attaining extensive wavelength coverage. To create a competitive material that evades these challenges, transitional amounts of Sn can be incorporated into Ge matrix to form …

Parity-Time Symmetry In A Coherent Atomic Medium, Jingliang Feng

Graduate Theses and Dissertations

Parity-time (PT) symmetry has attracted considerable attention since optics was realized with the ability to provide a fertile platform for the exploration of PT symmetry. Although many of the previous researches on PT symmetry have been conducted in solid-state system and the network of fiber loops, coherent atomic medium offers another platform for the exploration of PT symmetry due to its easy reconfigurability and flexible tunability in parameters.

This dissertation mainly focuses on the investigations of the phenomena related to PT-symmetric optical lattice in a coherent atomic medium. First, a controllable photonic crystal with periodic Raman gain was constructed in …

Analysis Of Titan's Fluvial Features Using Numerical Modeling, Jeshurun Horton

Mechanical Engineering Undergraduate Honors Theses

River channels have been observed near the Huygens probe landing site on the surface of Titan, along with evidence of rounded water ice boulders transported through fluid flow. Evidence near the landing site suggests active flow of liquid methane, which has motivated the study of the effects of sediment load and channel sizes on Titan’s fluvial features. A numerical model is used to determine the viscosity, flow velocity, and critical boulder transport diameter based on channel size, slope, and a range of sediment concentrations. This model achieves two ends: first, observed boulder diameters are used to determine the ideal channel …

Dreams Of Molecular Beams: Indium Gallium Arsenide Tensile-Strained Quantum Dots And Advances Towards Dynamic Quantum Dots (Moleculare Radiorum Somnia: Indii Gallii Arsenicus Tensa Quanta Puncta Et Ad Dinamicae Quantae Puntae Progressus), Kevin Daniel Vallejo

Boise State University Theses and Dissertations

Through the operation of a molecular beam epitaxy (MBE) machine, I worked on developing the homoepitaxy of high quality InAs with a (111)A crystallographic orientation. By tuning substrate temperature, we obtained a transition from a 2D island growth mode to step- ow growth. Optimized MBE parameters (substrate temperature = 500 °C, growth rate = 0.12 ML/s and V/III ratio ⩾ 40) lead to growth of extremely smooth InAs(111)A films, free from hillocks and other 3D surface imperfections. We see a correlation between InAs surface smoothness and optical quality, as measured by photoluminescence spectroscopy. This work establishes InAs(111)A as a platform …

Conceptual Insight Into The Application Of Innovative Educational Methods In Astronomy, Wahltyn A. Rattray

Theses and Dissertations

University students taking introductory astronomy courses were studied with a control group enrolled in a class with standard curriculum and an experimental group enrolled in a class with a curriculum using innovative instructional methods. Using multiple assessments, I analyzed the students’ astronomy knowledge and overall class experience to determine which curriculum was more instructionally effective. The innovative methods were developed with the ADDIE method and were based on the Karplus learning cycle which provided the framework for the astronomy curriculum. The end goal of the innovative curriculum is to produce graduates with better conceptual understanding of astronomy than with the …

Effects Of Collaborative Group Activities On Students’ Interest, Course Participation, And Performance In An Online Physics Course, Airik R. Sanchez

Theses and Dissertations

The purpose of this study was to investigate the impact of the use of collaborative work activities in online physics courses as perceived by students. Nearly identical surveys were administered at the beginning and end of two semesters to ascertain student perception on the impact of the utilization on their level of interest, participation, performance as well as teamwork skills. The results show that the majority of the population tested strongly agree that collaborative work had significant effect on all core areas tested, and they support the notion that it should be further utilized in both lecture and lab portions …

Contributions To The Heat Capacity Of Neutron Stars, Pedro Paulo Barboza Sanson

Theses and Dissertations

In this thesis, we review the contribution to the heat capacity of different matter phases that can appear inside a Neutron Star's core, paying special attention to the magnetic dual chiral density wave (MDCDW) phase, which is characterized by an inhomogeneous chiral condensate in the presence of a magnetic field and that is expected to be favored at intermediate densities and low temperatures. Furthermore, we compare our results with the observational lower limit of the core heat capacity established from observations of transiently accreting neutron stars which give us crucial information whether certain phases are feasible to appear in the …

Shipboard Lidar As A Tool For Remotely Measuring The Distribution And Bulk Characteristics Of Marine Particles, Brian Leigh Collister

OES Theses and Dissertations

Light detection and ranging (lidar) can provide remote estimates of the vertical distribution of optical properties in the ocean, potentially revolutionizing our ability to characterize the spatial structure of upper ocean ecosystems. However, challenges associated with quantifying the relationship between lidar measurements and biogeochemical properties of interest have prevented its adoption for routinely mapping the vertical structure of marine ecosystems. To address this, we developed a shipboard oceanographic lidar that measures attenuation (α) and linear depolarization (δ) at scales identical to those of in-water optical and biogeochemical measurements. The instrument’s ability to resolve the distribution of optical and biogeochemical properties …

Computational Study Of Grain Structure Evolution In Cdte/Cds Via Molecular Dynamics, Sharmin Abdullah

Open Access Theses & Dissertations

Grain structure analysis plays an important role in the identification of grain boundary characteristics, which can affect the efficiency of Cadmium Telluride/Cadmium Sulfide (CdTe/CdS) solar cells since they can act as recombination centers for carriers. Computer simulations such as molecular dynamics (MD) can be a very convenient and cost- effective method of investigating the growth evolution and grain structure of materials. The recently reported and experimentally validated MD simulated growth of polycrystalline CdTe/CdS films shows that these materials mostly consist of zinc blende (ZB) and wurtzite (WZ) structures, along with highly disordered atoms. However, little information about the semiconductor compound …

The Internal Charge Evolution Of Multilayered Materials Undergoing Mono-Energetic Electron Bombardment, Gregory Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The charging of multilayer materials as related to the charging of spacecraft is one of the primary concerns related to activities in the space environment. To understand how multilayer materials undergoing electron bombardment charge, an in-depth study of energy-dependent material properties must be undertaken. These properties include the electron penetration depth, secondary electron emission, charge transport and electrostatic discharge. By using energy dependent models of these properties, along with the geometry of the system, multilayer models can be developed to predict the time evolution of the internal charge distribution. Using these models, the net surface potential and the measurement of …

Capillary Driven Transport In Soft Solids, Saiful Islam Tamim

All Dissertations

Soft solids, such as polymeric gels, are elastic materials that can be significantly deformed by capillary forces which act at the interface. The coupling between elasticity and capillarity is known as elastocapillarity and is useful to wide ranging applications, from drop pinchoff of bioinks for 3-D printing tissue scaffolds, to generating droplet patterns on microfluidic devices. In this dissertation, we develop mathematical models of elastocapillary driven motions in soft solids. The focus is on understanding the relevant physics in such complex phenomena, while also recovering the limiting cases of classical fluid mechanics and solid mechanics theories.

This dissertation investigates two …

Ultrafast Magnetic Entropy Dynamics With Time-Resolved Pump-Probe Magneto-Optical Technique., Sahar Goharshenasanesfahani

Electronic Theses and Dissertations

It has been observed that ultrathin films, multilayers, or magnetic nanostructures indicate novel magnetic phenomena that differ profoundly from the respective bulk properties. Besides, because of the broad applications of these magnetic materials in the industry, they are an exciting research area. Hence, investigating the low-dimensional magnetic systems is one of the most active fields in experimental condensed matter physics. Magnetization dynamics can occur over a wide range of time scales (from seconds to femtoseconds). Some of these processes even occur on time scales as short as a few picoseconds (10^-12s) or femtoseconds (10^-15s). Measurement of …

Absolute Neutral Densities And Temperatures And Their Climatologies In The Middle Atmosphere Using An Optimal Estimation Method With Rayleigh-Scatter Lidar Observations Obtained At Utah State University, Jonathan L. Price

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Earth’s atmosphere is comprised of layers which can be defined by their temperature characteristics. These layers are the troposphere, stratosphere, mesosphere and thermosphere. The region where life exists is in the troposphere, however the study of the layers above is important as changes in these regions can directly impact, or indicate significant changes in, weather in the troposphere. The mesosphere is the least well-known region because it is the most difficult to observe. One of the best tools for observing this region is the Rayleigh-scatter lidar. It is capable of remotely observing the entirety of the mesosphere with good …

Geometrization Of Perfect Fluids, Scalar Fields, And (2+1)-Dimensional Electromagnetic Fields, Dionisios Sotirios Krongos

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Rainich equations provide a purely geometrical interpretation of matter in terms of the gravitational field it generates. All this takes place within the geometrical formulation of gravity provided by Einstein’s General Theory of Relativity. Rainich-type conditions giving spacetime "goemetrizations" are reviewed and extended. Three types of matter are considered: perfect fluids, scalar fields, and electromagnetic fields.