Physical Sciences and Mathematics Commons^™

Transferring Power Through A Magnetic Couple, Nickolas Cruz Villalobos Jr.

Senior Theses

Properties of several working magnetic coupled rotors have been measured and their performance compared to theoretical models. Axial magnetic couplers allow rotors to work within harsh environments, without the need for seals, proper alignment, or overload protection on a motor. The influence of geometrical parameters, such as distance from the center of the rotors, polarity arrangement, and the number of dipole pairs were experimentally tested. These results can be used to improve rotor designs, to increase strength and efficiency.

Exploring The Electrical Properties Of Twisted Bilayer Graphene, William Shannon

Senior Theses

Two-dimensional materials exhibit properties unlike anything else seen in conventional substances. Electrons in these materials are confined to move only in the plane. In order to explore the effects of these materials, we have built apparatus and refined procedures with which to create two-dimensional structures. Two-dimensional devices have been made using exfoliated graphene and placed on gold contacts. Their topography has been observed using Atomic Force Microscopy (AFM) confirming samples with monolayer, bilayer, and twisted bilayer structure. Relative work functions of each have been measured using Kelvin Probe Force Microscopy (KPFM) showing that twisted bilayer graphene has a surface potential …

Manufacturing And Testing The Permanent Magnet Linear Motor, Renjie Kang

Senior Theses

Controlled mechanical motion is vital in many useful applications in technology. Among them, linear motors have advantages over traditional rotating motors. In this work, we built a permanent magnet linear motor to test and measure its energy efficiency. A maximum 29% total energy efficiency, and 67% energy transfer rate, were detected. In addition, a C-shape support structure was added to the moving part in order to increase the moving accuracy. The tests show that, with the support structure, the fluctuation in the vertical direction decreases significantly, but the friction of the system slightly increases.

Quartic Metamaterials: The Inverse Method, Perturbations, And Bulk Optical Neutrality, Thomas Mulkey

Honors College Theses

A primary goal of photonics is designing material structures that support predetermined electromagnetic field distributions. We have developed an inverse method to determine material parameters for a quartic metamaterial from six desired plane waves. This work inspired us to study how perturbations to the parameters can result in optical neutrality.

Physics 4900, David Maughan

Physics Capstone Projects

More than a century has passed since Albert Einstein published his general theory of relativity. The theory has been tested many times experimentally, primarily in the relatively weak gravitational fields of the solar system [1,2]. More recently the first experimental results from the strong gravitational fields of two black holes have been measured in the form of gravitational waves, which are another prediction of general relativity. The 2017 Nobel prize in physics was awarded to Kip Thorne, Rainer Weiss, and Barry Barish for their role in the detection of gravitational waves. This year we have seen the first image of …

Specification-Based Grading Resources For Openstax College Physics (Ggc), Edward Forringer

Physics and Astronomy Ancillary Materials

This collection of ancillary materials for Introductory Biology was created under a Round Eleven Mini-Grant for Ancillary Materials Creation and Revision. Included are the following resources to assist a faculty member in implementing specification grading in an introductory physics course using OpenStax College Physics:

• Specification Grading Guide
• Specification Documents
• Quizzes
• Practice Final Exam

Author's Description:

"Rather than grading each assignment with partial credit and then taking a weighted average of your assignments to find a grade, this course uses a set of course expectations called “specifications” (spec for short). Each spec has an associated quiz. Some specifications are designated “critical.” …

Adding Student Video Projects To Physics Courses, David Abbott, Andrew Roberts, Dan L. Macisaac, Kathleen Falconer, Florian Genz, Stefan Hoffmann, Andre Bresges, Jeremias Weber

Videos for Physics Teaching

Physics students have traditionally prepared many kinds of reports—laboratory, activity, project, and even book or article reports. Smartphones and YouTube videos are familiar cultural objects to current students, and our students use smartphone cameras to include photographs of apparatus, phenomena, hand-sketched figures, graphs, and mathematical equations in their physics reports. Here we present basic techniques for physics students to use smartphones and tablets to create short (< 5 min) end-of-semester video projects. Our students mainly use Apple Computer’s iPad1 tablets, but also other tablets and various smartphones. Finally we discuss appropriate instructor expectations and grading. Similar non-physics student video reporting efforts were reported using video cameras by Kearney,2 and Hechter and Guy.3

The Hottest Color For The Fastest Ride: A Problem-Based Unit Of Instruction For The Elementary And Middle School Science Classroom, Madison Wells

Mahurin Honors College Capstone Experience/Thesis Projects

There is a major gap in the availability of Next Generation Science Standard focused curriculum that effectively utilizes technology to solve real-world problems in an authentic way. “The Hottest Color for the Fastest Ride” will allow students to participate in the real-world application of reflection absorption of light and heat due to color through designing, building, and testing two dual-tone corvettes. This three-day unit of physics instruction designed for fourth- and fifth- grade science classrooms will be tied to a grand challenge that tasks the students with designing a dual-tone car that will stay cool during Kentucky’s hot summer weather …

Ordered Growth Of Ferroelectric Diisopropylammonium-Bromide Microcrystals Through Slotted-Jar Growth And Lithographically Controlled Wetting, Andrew J. Fanning

Honors Program: Senior Projects (Public)

Organic molecular ferroelectrics show promise for industry applications because of their switchable high spontaneous polarization value, mechanical flexibility, and cost-effectiveness. Since these materials, namely diisopropylammonium bromide, exhibit ferroelectricity only in tandem with a high level of crystallinity, novel methods must be explored in order to ensure that high levels of crystallinity are achieved. This project seeked to perfect the methods of Slotted Jar Growth and Lithographically Controlled Wetting (LCW). Slotted Jar Growth uses temperature driven solution saturation to grow crystals on a desired substrate. LCW drives the growth of microscopic diisopropylammonium bromide crystals, in their ferroelectric phase, through the use …

Identified Flying Objects: A Multidisciplinary Scientific Approach To The Ufo Phenomenon, Dr. Michael P. Masters

Interdisciplinary Arts and Sciences Books

Identified Flying Objects cautiously examines the premise that ‘UFOs’ & ‘Aliens’ are simply our distant human descendants, returning from the future to study their own hominin evolutionary past. This text challenges readers to consider new possibilities while cultivating conversations about our ever-evolving understanding of time & time travel.

Efficient Numerical Methods For Chemotaxis And Plasma Modulation Instability Studies, Truong B. Nguyen

Browse all Theses and Dissertations

In this thesis, we develop efficient numerical solvers for nonlinear systems of partial differential equations (PDEs). These systems of PDEs concern two different sets of physical problems. The first set includes chemotaxis models such as Keller-Segel models and cancer cell invasion models. Solutions of these models are observed to experience the blow-up phenomenon or the development of sharp and spiky features. Therefore, efficient and accurate numerical techniques must be employed in order to capture the solutions' behaviors. For this research, we design efficient solvers for these systems in the one and two spatial dimensions. In particular, we plan to apply …

Oscillatory Behavior Of Hollow Grid Cathode Discharges, Roman Schrittwieser, Claudia-Teodora Teodorescu-Soare, Florin Enescu, Codrina Ionita, Dan-Gheorghe Dimitriu, Silviu Gurlui, Federico Mazzanti, Stefan-Andrei Irimiciuc, Bianca Hodoroaba, Turlough O'Hara, Ovidiu Vasilovici, Lidia Amarandi

Conference Papers

Multiple complex space-charge structures in unmagnetized low-temperature plasmas arise from ionization phenomena near additional negatively or positively biased electrodes or due to local constraints. Because of their usually spherical form, such structures are called fireballs. If they appear inside hollow grids, they are called inverted fireballs or plasma bubbles. The temporal evolution of such structures is often accompanied by strong plasma instabilities. The dynamics of complex space-charge structures have been investigated by using single spherical grid cathode with an orifice. Langmuir probe and optical emission spectroscopy were used to diagnose the structures. Measurements delivered the axial profiles of the plasma …

Development Of Nonlocal Green-Kubo Formalism With Applications To Coupled Heat And Mass Transport, Kevin Fernando

Honors Undergraduate Theses

Nonlocal equations for coupled heat and mass transport are developed within the Green-Kubo formalism. Nonlocal thermal transport in Lennard-Jones solids is computed to establish the existence of semi-ballistic transport. Deviations from the diffusive theory are shown by comparing the Fourier transform of the response function from the nonlocal theory to that of the diffusive one. It is shown that the deviations from the local theory correspond to acoustic phonons, whose frequency dependence gives rise to the observed deviations from the local theory.

Delivering Sustained, Coordinated, And Integrated Observations Of The Southern Ocean For Global Impact, Louise Newman, Petra Heil, Rowan Tebilco, Katsuro Katsumata, Andrew Constable, Esmee Van Wijk, Karen Assmann, Joana Beja, Phillippa Bricher, Richard Coleman, Daniel Costa, Steve Diggs, Riccardo Farneti, Sarah Fawcett, Sarah T. Gille, Katharine R. Hendry, Sian Henly, Eileen Hofmann, Ted Maksym, Matthew Mazloff, Andrew Meijers, Michael M. Meredith, Sebastien Moreau, Burcu Ozsoy, Robin Robertson, Irene Schloss, Oscar Schofield, Jiuxin Shi, Elisabeth Sikes, Inga J. Smith, Sebastiaan Swart, Anna Wahlin, Guy Williams, Michael J. M. Williams, Laura Herraiz-Borreguero, Stefan Kern, Jan Lieser, Robert A. Massom, Jessica Melbourne-Thomas, Patricia Miloslavich, Gunnar Spreen

CCPO Publications

The Southern Ocean is disproportionately important in its effect on the Earth system, impacting climatic, biogeochemical, and ecological systems, which makes recent observed changes to this system cause for global concern. The enhanced understanding and improvements in predictive skill needed for understanding and projecting future states of the Southern Ocean require sustained observations. Over the last decade, the Southern Ocean Observing System (SOOS) has established networks for enhancing regional coordination and research community groups to advance development of observing system capabilities. These networks support delivery of the SOOS 20-year vision, which is to develop a circumpolar system that ensures time …

Florida Science: The Science That Makes Florida Different, Terence W. Cavanaugh

Secondary Level Resources

This book was created to assist students with their understanding of how science occurs in Florida. When teaching science or any subject it’s important to remember to begin with the concrete and then move to the abstract. I have found that it has helped my students when I begin by teaching science concepts in a concrete manner and expand from there. For example, when I taught about topographic maps, the students were much more successful in their learning when I started with local topographic maps that included the school and the surrounding area than with places that had mountains or …

Charge Storage In Wo³ Polymorphs And Their Application As Supercapacitor Electrode Material, Vaibhav Lokhande, Abhishek Lokhande, Gon Namkoong, Jin Hyeok Kim, Taeksoo Ji

Electrical & Computer Engineering Faculty Publications

Tungsten oxide is a versatile material with different applications. It has many polymorphs with varying performance in energy storage application. We report simple and facile way to synthesize four phases of tungsten oxide from same precursor materials only by changing the pH and temperature values. Monoclinic, hexagonal, orthorhombic and tetragonal phase obtained, were analyzed and tested for supercapacitor application. The electrochemical analysis of four phases indicates that the hexagonal phase is best-suited electrode material for supercapacitor. The hexagonal phase exhibits higher specific capacitance (377.5 Fg^-1 at 2 mVs^-1), higher surface capacitive contribution (75%), better stability and rate …

The Encyclopedia Of Neutrosophic Researchers - Vol. 3, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

This is the third volume of the Encyclopedia of Neutrosophic Researchers, edited from materials offered by the authors who responded to the editor’s invitation. The authors are listed alphabetically. The introduction contains a short history of neutrosophics, together with links to the main papers and books. Neutrosophic set, neutrosophic logic, neutrosophic probability, neutrosophic statistics, neutrosophic measure, neutrosophic precalculus, neutrosophic calculus and so on are gaining significant attention in solving many real life problems that involve uncertainty, impreciseness, vagueness, incompleteness, inconsistent, and indeterminacy. In the past years the fields of neutrosophics have been extended and applied in various fields, such as: …

The Magnetocaloric Effect & Performance Of Magnetocaloric Materials In A 1d Active Magnetic Regenerator Simulation, Daniel Nicholas Bayer

Browse all Theses and Dissertations

Active magnetic regenerators (AMRs) operate according to the magnetothermal phenomenon known as the magnetocaloric effect (MCE), and are at the forefront of magnetic cooling technology. AMR simulations have been shown to be useful tools in predicting the performance of different magnetocaloric materials (MCMs) without the need to develop a physical prototype. In a search to determine the set of operational parameters which would maximize MCM performance, a 1D simulation of an AMR device has been developed in Matlab. Gadolinium, the most well-documented MCM, is used as a benchmark material to study the effects of varying certain operational parameters such as …

Exploring The Diffuse Neutral Hydrogen In And Around Nearby Galaxies, Amy Sardone

Graduate Theses, Dissertations, and Problem Reports (ETD)

We explore the environment of 36 nearby galaxies in neutral hydrogen (H I) as part of the MeerKAT H I Observations of Nearby Galactic Objects; Observing Southern Emitters (MHONGOOSE) survey with the Robert C. Byrd Green Bank Telescope (GBT), and the Imaging Galaxies Intergalactic and Nearby En- vironment (IMAGINE) survey with the Parkes Radio Telescope. We obtained deep observations of each of these galaxies, reaching column density detection sensitivities as low as NHI ∼ 1e17 cm^−2, which allowed us to quantify the amount of diffuse H I in both samples of galaxies. This allows us to search for evidence of …

Practical Chaos: Using Dynamical Systems To Encrypt Audio And Visual Data, Julia Ruiter

Scripps Senior Theses

Although dynamical systems have a multitude of classical uses in physics and applied mathematics, new research in theoretical computer science shows that dynamical systems can also be used as a highly secure method of encrypting data. Properties of Lorenz and similar systems of equations yield chaotic outputs that are good at masking the underlying data both physically and mathematically. This paper aims to show how Lorenz systems may be used to encrypt text and image data, as well as provide a framework for how physical mechanisms may be built using these properties to transmit encrypted wave signals.

Investigation Of Narrow Bipolar Events In Mississippi Thunderstorms, Sampath Asiri Bandara

Electronic Theses and Dissertations

In the first part of the study FA and Log-RF data were used to examine low-altitude (<8.0 km) negative NBEs (NNBEs) to see how many -CG flashes were initiated by NNBEs. Out of 686 -CG flashes only 33 (5%) flashes were initiated by an NNBE. These NNBEs occurred at an average altitude of 6.2 km had average amplitude (range-normalized amplitude to 100 km) of 0.4 V/m and had average VHF (Log-RF) power of 130 W. Since the low-altitude NNBEs were substantially weaker than positive NBEs that initiate intracloud (IC) flashes it is hypothesized that -CG flashes are easier to initiate than IC flashes. The second part of the study investigated the properties of 201 positive NBEs (+NBEs). The +NBEs were classified in two ways: into Types A-D [Karunarathne et al. 2015] and into three different groups: Isolated Not-isolated and IC flash-initiator or INBE [Wu et al. 2014]. The average VHF (Log-RF) power of NBEs within the A-D categories were 1.9 4 9.8 and 13.2 kW respectively while the powers for the Isolated Not-isolated and INBE categories were 10.1 4 and 10.1 kW respectively. The third study considered 34 NBEs that occurred close in space and time to each other: 13 pairs of NBEs one group of three +NBEs and one group of five +NBEs. The NBEs were overlaid on radar data of the parent thunderstorms. The data indicate that the individual NBEs in each group initiated in separate intense electric field regions of small extent rather than in a single large-scale electric field region. This dissertation investigates Narrow Bipolar Events (NBEs) which are a type of short-duration (10- 30 µs) lightning discharge. The study primarily used data from NBEs collected in 2016 at seven sensor sites within 50 km of Oxford Mississippi USA. Each sensor site had three electromagnetic antennas called Fast Antenna (FA) dE⁄dt and Log-RF with bandwidths of 0-2.5 MHz 0-1.0 MHz and 186-192 MHz respectively. NBEs are often isolated from other lightning events in thunderclouds but they sometimes initiate negative cloud-to-ground (-CG) and intracloud (IC) lightning flashes or they can occur during these flashes.

Modelling Potential Fluctuations In Double Layer Graphene Systems As A Periodic Oscillation In Electron Density & Its Effect On Coulomb Drag, Ryan Bogucki

Williams Honors College, Honors Research Projects

An expression for the drag transresistivity in a graphene double layer system exhibiting potential fluctuations modelled as a periodic oscillation in electron density is derived. Our model starts from the Coulombic interaction and we derive the correlation between a sinusoidal fluctuation in electron density in the first layer and the induced electron density in the second layer. Previous models in the literature have employed an arbitrary correlation between each layer’s electron density, and the model presented is the first attempt in the literature to explicitly derive this correlation. Recent experiments have found that the drag transresistivity in graphene double layers …

Improved Momentum Spread For Precision Physics Experiments Using Wedges, Nick Amato

Graduate Research Theses & Dissertations

High precision experiments have become key in the search for physics beyond the Standard Model. One measurement that can be made in order to expand our knowledge of the Standard Model is the precise measurement of the magnetic dipole moment (MDM) of the muon. In order to perform this precise measurement of the MDM of muons, the storage of particles with a precisely known momentum in a highly uniform magnetic field is required.

This thesis is focused on how one may use a wedge of energy absorbing material and the optical parameters of an accelerator lattice to improve upon the …

Evaluation Of X-Ray Spectroscopic Techniques For Determining Temperature And Density In Plasmas, Theodore Scott Lane

Graduate Theses, Dissertations, and Problem Reports (ETD)

Temperature and density measurements of plasmas are important for understanding various phenomena. For example, equations of state, most scaling arguments for Inertial Confinement Fusion and laboratory astrophysics all rely upon accurate knowledge of temperature and density. Spectroscopy is a non-invasive technique to measure these quantities. In this work we establish a new spectroscopic technique by using it to determine temperature. We also compare and contrast the capability of two codes, PrismSPECT and ATOMIC, to infer electron density from experimentally acquired spectra via Stark broadening.

We compare and contrast the capability of isoelectronic line ratios and inter-stage line ratios in an …

Pdfs In Small Boxes, Raúl A. Briceño, Juan V. Guerrero, Maxwell T. Hansen, Christopher J. Monahan

Physics Faculty Publications

PDFs can be studied directly using lattice QCD by evaluating matrix elements of non-local operators. A number of groups are pursuing numerical calculations and investigating possible systematic uncertainties. One systematic that has received less attention is the effect of calculating in a finite spacetime volume. Here we present first attempts to assess the role of the finite volume for spatially non-local operators. We find that these matrix elements may suffer from large finite-volume artifacts and more careful investigation is needed.

Announcement: In Memory Of Yong Ho Chin, Michael Thoennessen, Debbie Brodbar, Brant Johnson, Jean Delayen, Dan Kulp, Frank Zimmermann, Maria Poko

Physics Faculty Publications

No abstract provided.

Measurement Of Nuclear Transparency Ratios For Protons And Neutrons, M. Duer, O. Hen, E. Piasetzky, L. B. Weinstein, A. Schmidt, I. Korover, E. O. Cohen, H. Hakobyan, S. Adhikari, G. Angelini, H. Avakian, C. Ayerbe Gayoso, L. Barion, M. Battaglieri, A. Beck, I. Bedlinski, A. S. Biselli, S. Boiarinov, W. J. Briscoe, X. Zheng, Et Al., The Clas Collaboration

Physics Faculty Publications

This paper presents, for the first time, measurements of neutron transparency ratios for nuclei relative to C measured using the (e, e'n) reaction, spanning measured neutron momenta of 1.4 to 2.4 GeV/c. The transparency ratios were extracted in two kinematical regions, corresponding to knockout of mean-field nucleons and to the breakup of Short-Range Correlated nucleon pairs. The extracted neutron transparency ratios are consistent with each other for the two measured kinematical regions and agree with the proton transparencies extracted from new and previous (e, e'p) measurements, including those from neutron-rich nuclei such as lead. The data also agree with and …

Solutions For Fermi Questions, November 2019: Question 1: Cell Phones Make Me Boil; Question 2: Charging The Phone, Larry Weinstein

Physics Faculty Publications

Answers to the Fermi questions:

How much water can you boil with the energy stored in a cell phone battery?

How much does the electrical energy for a cell phone cost each year?

Spectroscopy Of Neon For The Advanced Undergraduate Laboratory, H. C. Busch, M. B. Cooper, C. I. Sukenik

Physics Faculty Publications

We describe a spectroscopy experiment, suitable for upper-division laboratory courses, that investigates saturated absorption spectroscopy and polarization spectroscopy in a neon discharge. Both experiments use nearly identical components, allowing students to explore both techniques in a single apparatus. Furthermore, because the wavelength of the laser is in the visible part of the spectrum (640 nm), the experiment is well-suited for students with limited experience in optical alignment. The labs nicely complement a course in atomic or plasma physics, provide students with the opportunity to gain important technical skills in the area of optics and lasers, and can provide an introduction …

Instability Of Flux Flow And Production Of Vortex-Antivortex Pairs By Current-Driven Josephson Vortices In Layered Superconductors, Ahmad Sheikhzada, Alex Gurevich

Physics Faculty Publications

We report numerical simulations of the nonlinear dynamics of Josephson vortices driven by strong dc currents in layered superconductors. Dynamic equations for interlayer phase differences in a stack of coupled superconducting layers were solved to calculate a drag coefficient η(J) of the vortex as a function of the perpendicular dc current density J. It is shown that Cherenkov radiation produced by a moving vortex causes significant radiation drag increasing η(v) at high vortex velocities v and striking instabilities of driven Josephson vortices moving faster than a terminal v_c. The steady-state flux flow breaks down at ν > v …