Physical Sciences and Mathematics Commons^™

Sedimentology And Stratigraphy Of High-Latitude, Glacigenic Deposits From The Late Paleozoic Ice Age In The Tepuel-Genoa Basin, Patagonia, Argentina, Sarah Rose Survis

Theses and Dissertations

The Late Paleozoic Ice Age (LPIA) was the longest lived ice age of the Phanerozoic lasting ~87 million years. During this time multiple, small ice sheets advanced and retreated with alternating glacial and nonglacial intervals across Gondwana. Controversy still remains over the size, timing, and number of ice sheets because the traditional view of Gondwana during this time is of a single, large ice sheet that waxed and waned across the supercontinent. Furthermore, high-latitude glacially-influenced basins during the Carboniferous have received limited attention, underscoring the poor understanding of glacial to non-glacial transitions. The Tepuel Basin in Patagonia, Argentina, was located …

A Weak Simpson Method For A Class Of Stochastic Differential Equations And Numerical Stability Results, Ram Sharan Adhikari

Theses and Dissertations

This work proposes a novel weak Simpson method for numerical solution for a class of stochastic differential equations. We show that such a method has weak convergence of order one in general and weak convergence of order three under certain additional assumptions. This work also aims to determine the mean-square stability region of the weak Simpson method for linear stochastic differential equations with multiplicative noises. In this work, a mean-square stability region of the weak Simpson scheme is identified, and stepsizes for the numerical method where errors propagation are under control in well-defined sense are given. The main results are …

Random Iteration Of Rational Maps, Jesse Dean Feller

Theses and Dissertations

Random and non-autonomous iteration has been a subject of interest in Mathematics that has received some attention in the last few decades. The earliest paper on random iteration in the complex setting was written by Fornaess and Sibony. They have shown that given a family of functions $\{f_c\}_{c \in \W}$ where $\W$ is a small open set, for almost every z the random iteration is stable on a subset of $\W^\N$ of full probability measure. Later, Hiroki Sumi further extended these results to a more general situation using rational semigroups. We will show that the results of Fornaess and Sibony …

Multivariate Hilbert Series Of Lattice Cones And Homogeneous Varieties, Wayne Andrew Johnson

Theses and Dissertations

We consider the dimensions of irreducible representations whose highest weights

lie on a given finitely generated lattice cone. We present a rational function representing

the multivariate formal power series whose coefficients encode these dimensions.

This result generalizes the formula for the Hilbert series of an equivariant

embedding of an homogeneous projective variety. We use the multivariate generating

function to compute Hilbert series for the Kostant cones and other affine and

projective varieties of interest in representation theory. As a special case, we show

how the multivariate series can be used to compute the Hilbert series of the three

classical families …

Creation Of Carbon Nanotube Based Biosensors Through Dielectrophoretic Assembly, Nilan S. Mani, Steve Kim, Kaushik Annam, Danielle Bane, Guru Subramanyam

Electrical and Computer Engineering Faculty Publications

Due to their excellent electrical, optical, and mechanical properties, nanosized single wall carbon nanotubes (SWNTs) have attracted significant attention as a transducing element in nano-bio sensor research. Controlled assembly, device fabrication, and bio-functionalization of the SWNTs are crucial in creating the sensors. In this study, working biosensor platforms were created using dielectrophoretic assembly of single wall carbon nanotubes (SWNTs) as a bridge between two gold electrodes. SWNTs in a commercial SDS surfactant solution were dispensed in the gap between the two gold electrodes, followed by applying an ac voltage across the two electrodes. The dielectrophoresis aligns the CNTs and forms …

Chesapeake Bay Nitrogen Fluxes Derived From A Land-Estuarine Ocean Biogeochemical Modeling System: Model Description, Evaluation, And Nitrogen Budgets, Yang Feng, Marjorie A.M. Friedrichs, John Wilkin, Hanqin Tian, Qichun Yang, Eileen E. Hofmann, Jerry D. Wiggert, Raleigh R. Hood

Faculty Publications

The Chesapeake Bay plays an important role in transforming riverine nutrients before they are exported to the adjacent continental shelf. Although the mean nitrogen budget of the Chesapeake Bay has been previously estimated from observations, uncertainties associated with interannually varying hydrological conditions remain. In this study, a land-estuarine-ocean biogeochemical modeling system is developed to quantify Chesapeake riverine nitrogen inputs, within-estuary nitrogen transformation processes and the ultimate export of nitrogen to the coastal ocean. Model skill was evaluated using extensive in situ and satellite-derived data, and a simulation using environmental conditions for 2001–2005 was conducted to quantify the Chesapeake Bay nitrogen …

High-Order Threshold Corrections For Top-Pair And Single-Top Production, Nikolaos Kidonakis

Faculty Articles

I present results for high-order corrections from threshold resummation to cross sections and differential distributions in top-antitop pair production and in single-top production. I show aN3LO results for the total tt¯ cross section as well as for the top-quark transverse momentum (pT) and rapidity distributions, and the top-quark forward-backward asymmetry in tt¯production. I compare with the most recent Tevatron and LHC data, including at 13 TeV. I also present aNNLO results for cross sections and pT distributions in t-channel, s-channel, and tW-channel single-top production.

Automatic Registration Of Optical Aerial Imagery To A Lidar Point Cloud For Generation Of City Models, Bernard Olushola Abayowa, Alper Yilmaz, Russell C. Hardie

Electrical and Computer Engineering Faculty Publications

This paper presents a framework for automatic registration of both the optical and 3D structural information extracted from oblique aerial imagery to a Light Detection and Ranging (LiDAR) point cloud without prior knowledge of an initial alignment. The framework employs a coarse to fine strategy in the estimation of the registration parameters. First, a dense 3D point cloud and the associated relative camera parameters are extracted from the optical aerial imagery using a state-of-the-art 3D reconstruction algorithm. Next, a digital surface model (DSM) is generated from both the LiDAR and the optical imagery-derived point clouds. Coarse registration parameters are then …

Graph Centers, Hypergraph Degree Sequences, And Induced-Saturation, Sarah Lynne Behrens

Department of Mathematics: Dissertations, Theses, and Student Research

The center of a graph is the set of vertices whose distance to other vertices is minimal. The centralizing number of a graph G is the minimum number of additional vertices in any graph H where V(G) is the center of H. Buckley, Miller, and Slater and He and Liu provided infinite families of graphs with each centralizing number. We show the number of graphs with each nonzero centralizing number grows super-exponentially with the number of vertices. We also provide a method of altering graphs without changing the centralizing number and give results about the centralizing …

Anharmonic Properties In Mg₂X (X= C, Si, Ge, Sn, Pb) From First-Principles Calculations, Aleksandr V. Chernatynskiy, Simon R. Phillpot

Physics Faculty Research & Creative Works

Thermal conductivity reduction is one of the potential routes to improve the performance of thermoelectric materials. However, detailed understanding of the thermal transport of many promising materials is still missing. In this paper, we employ electronic-structure calculations at the level of density functional theory to elucidate thermal transport properties of the Mg₂X (X=C, Si, Ge, Sn, and Pb) family of compounds, which includes Mg₂Si, a material already identified as a potential thermoelectric. All these materials crystallize into the same antifluorite structure. Systematic trends in the anharmonic properties of these materials are presented and examined. Our calculations …

Beta-Binomial Kriging: A New Approach To Modeling Spatially Correlated Proportions, Aimee Schwab

Department of Statistics: Dissertations, Theses, and Student Work

Spatially correlated count data sets appear often in applied data analysis problems, but there is little consensus in the literature about how best to analyze the data. The two prevailing approaches provide accurate parameter estimates and predictions, at the cost of model interpretability and simplicity. This dissertation will present a new approach to modeling spatially correlated binomial observations: beta-binomial kriging. The model proposed here is a modified form of spatial kriging which assumes the data are generated from a correlated beta-binomial distribution. Given this assumption, the spatial parameters and predicted values can be estimated using simple matrix algebra. Beta-binomial kriging …

Confirming Hd 23478 As A New Magnetic B Star Hosting An Hα-Bright Centrifugal Magnetosphere, J. Sikora, G. A. Wade, D. A. Bohlender, C. Neiner, M. E. Oksala, M. Shultz, David H. Cohen, A. Ud-Doula, J. Grunhut, D. Monin, S. Owocki, V. Petit, T. Rivinus, R. H. D. Townsend

Physics & Astronomy Faculty Works

In this paper, we report 23 magnetic field measurements of the B3IV star HD 23478: 12 obtained from high-resolution Stokes V spectra using the ESPaDOnS (Canada–France–Hawaii Telescope) and Narval (Télescope Bernard Lyot) spectropolarimeters, and 11 from medium-resolution Stokes V spectra obtained with the DimaPol spectropolarimeter (Dominion Astronomical Observatory). HD 23478 was one of two rapidly rotating stars identified as potential ‘centrifugal magnetosphere’ hosts based on IR observations from the Apache Point Observatory Galactic Evolution Experiment survey. We derive basic physical properties of this star including its mass (M=6.1+0.8−0.7M⊙), effective temperature (Teff = 20 ± 2 kK), radius (R=2.7+1.6−0.9R⊙), and age …

Guidelines For Good Mathematical Writing, Francis Su

All HMC Faculty Publications and Research

Communicating mathematics well is an important part of doing mathematics. Many of us know from writing papers or giving talks that communicating effectively not only serves our audience but also clarifies and structures our own thinking. There is an art and elegance to good writing that every writer should strive for. And writing, as a work of art, can bring a person great personal satisfaction.

Within the MAA, we value exposition and mathematical communication. In this column, I’m sharing the advice I give my students to help them write well. There are more extensive treatments (e.g., see Paul Halmos’s How …

Time-Series Evaluation Of Suspect Rickettsiales-Like Bacteria Presence In Acropora Cervicornis Off Of Broward County From Years 2001–2012, Steven Di Lauro

HCNSO Student Theses and Dissertations

Rickettsiales-like organisms (RLOs) are thought to be related to bacteria in the order Rickettsiales. They have been reported to occur in the staghorn coral (Acropora cervicornis), and this study investigated trends of infection over time, and in relation to the health of infected corals. This study focuses on tissue samples taken mostly from visibly healthy A. cervicornis thickets in Broward County, Florida, and processed for histological examination. Samples were originally collected and analyzed to document reproduction during years 2001 through 2012, and tissue loss diseases (white-band disease [WBD] types I and II, and rapid tissue loss). …

A Comparative Evaluation Of Mitigation Wetlands In Broward County, Florida, Using Chironomid (Ditera) Pupal Exuviae: A Potential Technique For Assessing Mitigation Success, Ryan St. George

HCNSO Student Theses and Dissertations

Wetland resources in South Florida are regulated at three redundant jurisdictional levels: local or municipal regulations set forth by many independent jurisdictions, State regulations derived directly from Florida Statutes, and Federal regulations promulgated primarily under the Clean Water Act. All three levels of government can have jurisdiction over projects that affect regulated wetland resources, yet inconsistent policies and standards remain and continue to confound regulators despite decades of intensive coordination efforts and a rapidly growing scientific research base. The size of a wetland mitigation area is of primary consideration when evaluating its perceived ecological value, although wetland mitigation areas constructed …

Theoretical Study Of Magnetoelectric Effects In Noncentrosymmetric And Cuprate Superconductors, Manoj Kumar Kashyap

Theses and Dissertations

A century after the discovery of superconductivity at the lab of Kamerlingh Onnes

in 1911, it is noticeable that the phenomenon is quite ubiquitous in nature. In addi-

tion to a long list of superconducting alloys and compounds, almost half the elements

in the periodic table superconduct. By the late seventies, superconductivity was

thought to be well understood. This turned out to be a myth, with the discovery of

unconventional superconductors that defied Bardeen-Cooper-Schrieffer (BCS) theory.

Cuprates have been the most prominent example among them ever since their discov-

ery in 1986 by Bednorz and M ̈uller. Another example of …

Exmouth Gulf Prawn Managed Fishery, M. I. Kangas, E. C. Sporer, S. A. Hesp, K. L. Travaille, N. Moore, P. Cavalli, E. A. Fisher

WA Marine Stewardship Council report series

This report provides a comprehensive description of the Exmouth Gulf Prawn Managed Fishery (EGPMF) in Western Australia and contains information relevant to assist the assessment of this fishery against the Marine Stewardship Council (MSC) standard (v1.3) for sustainable fishing. The EGPMF uses demersal otter trawl gear to target predominantly brown tiger prawns (Penaeus esculentus) and western king prawns (Penaeus latisulcatus).

Rényi Entanglement Entropy Of Critical Su(N) Spin Chains, Jonathan D'Emidio, Matthew S. Block, Ribhu K. Kaul

Physics and Astronomy Faculty Publications

We present a study of the scaling behavior of the Rényi entanglement entropy (REE) in SU(N) spin chain Hamiltonians, in which all of the spins transform under the fundamental representation. These SU(N) spin chains are known to be quantum critical and described by a well known Wess-Zumino-Witten (WZW) nonlinear sigma model in the continuum limit. Numerical results from our lattice Hamiltonian are obtained using stochastic series expansion quantum Monte Carlo for both closed and open boundary conditions. As expected for this 1D critical system, the REE shows a logarithmic dependence on the subsystem size with a …

Energy Dependence Of Kπ, Pπ, And Kp Fluctuations In Au + Au Collisions From √SNn=7.7 To 200 Gev, James K. Adkins, Renee H. Fatemi, Suvarna Ramachandran, L. Adamczyk, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, A. Aparin, D. Arkhipkin, E. C. Aschenauer, G. S. Averichev

Physics and Astronomy Faculty Publications

A search for the quantum chromodynamics (QCD) critical point was performed by the STAR experiment at the BNL Relativistic Heavy Ion Collider, using dynamical fluctuations of unlike particle pairs. Heavy ion collisions were studied over a large range of collision energies with homogeneous acceptance and excellent particle identification, covering a significant range in the QCD phase diagram where a critical point may be located. Dynamical Kπ, pπ, and Kp fluctuations as measured by the STAR experiment in central 0–5% Au + Au collisions from center-of-mass collision energies √^sNN=7.7 to 200 GeV are presented. The observable …

Measurements Of Dielectron Production In Au + Au Collisions At √SNn = 200 Gev From The Star Experiment, James K. Adkins, Renee H. Fatemi, Suvarna Ramachandran, L. Adamczyk, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, A. Aparin, D. Arkhipkin, E. C. Aschenauer, G. S. Averichev

Physics and Astronomy Faculty Publications

We report on measurements of dielectron (e⁺e⁻) production in Au + Au collisions at a center-of-mass energy of 200 GeV per nucleon-nucleon pair using the STAR detector at BNL Relativistic Heavy Ion Collider. Systematic measurements of the dielectron yield as a function of transverse momentum (p_T) and collision centrality show an enhancement compared to a cocktail simulation of hadronic sources in the low invariant-mass region (M_ee < 1 GeV/c²). This enhancement cannot be reproduced by the ρ-meson vacuum spectral function. In minimumbias collisions, in the invariant-mass range of 0.30–0.76 …

Higgs Boson Equation In De Sitter Spacetime: Numerical Investigation Of Bubbles Using Gpus, Jacob N. Banda

Theses and Dissertations - UTB/UTPA

The Higgs field, along with its corresponding boson, represent a milestone for modern day particle physics. In this work we consider the Higgs boson equation in de Sitter spacetime. Previous work by K. Yagdjian [23] has formulated sufficient conditions for the existence of the zeros of global solutions in the interior of their supports. In searching for such solutions, we turn to heterogeneous parallel computing, which allows for faster computation through graphical processing units (GPUs). Armed with general-purpose computation on graphics hardware (GPGPU) techniques and explicit numerical schemes, we approximate solutions of the equation for the Higgs boson along with …

Ecological And Biogeographic Null Hypotheses For Comparing Rarefaction Curves, Luis Cayuela, Nicholas J. Gotelli, Robert K. Colwell

College of Arts and Sciences Faculty Publications

The statistical framework of rarefaction curves and asymptotic estimators allows for an effective standardization of biodiversity measures. However, most statistical analyses still consist of point comparisons of diversity estimators for a particular sampling level. We introduce new randomization methods that incorporate sampling variability encompassing the entire length of the rarefaction curve and allow for statistical comparison of i ≥ 2 individual-based, sample-based, or coverage-based rarefaction curves. These methods distinguish between two distinct null hypotheses: the ecological null hypothesis (H0eco) and the biogeographical null hypothesis (H0biog). H0eco states that the i samples were drawn from a single assemblage, and any differences …

Improving The Scalability And Usability Of The Public Information Officer Monitoring Application, Rohan D. Shah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis work addresses the limitations of a web application called the Public Information Officer Monitoring Application (PMA). This application helps Public Information Officers (PIOs) to gather, monitor, sort, store, and report social media data during a crisis event. Before this work, PMA was unable to handle large data sets and as a result, it had not been adequately tested with potential users of the application.

This thesis describes changes made to PMA to improve its ability to handle large data sets. After these changes were made, the application was then tested with target users. All test participants found the …

Face Recognition Under Varying Illuminations, Mohammadreza Faraji

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Face recognition under illumination is really challenging. This dissertation proposes four effective methods to produce illumination-invariant features for images with various levels of illuminations. The proposed methods are called logarithmic fractal dimension (LFD), eight local directional patterns (ELDP), adaptive homomorphic eight local directional pat- terns (AH-ELDP), and complete eight local directional patterns (CELDP), respectively.

LFD, employing the log function and the fractal analysis (FA), produces a logarithmic fractal dimension (LFD) image that is illumination-invariant. The proposed FA feature-based method is an effective edge enhancer technique to extract and enhance facial features such as eyes, eyebrows, nose, and mouth.

The proposed …

Image Blur Detection With Two-Dimensional Haar Wavelet Transform, Sarat Kiran Andhavarapu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Efficient detection of image blur and its extent is an open research problem in computer vision. Image blur has a negative impact on image quality. Blur is introduced into images due to various factors including limited contrast, improper exposure time or unstable device handling. Toward this end, an algorithm is presented for image blur detection with the use of Two-Dimensional Haar Wavelet transform (2D HWT). The algorithm is experimentally compared with two other image blur detection algorithms frequently cited in the literature. When evaluated over a sample of images, the algorithm performed on par or better than the two other …

Seismic-Hazard Map Of Southeast Missouri And Likely Magnitude Of The February 1812 New Madrid Earthquake, Jaewon Chung, J. David Rogers

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The New Madrid seismic zone lies beneath the upper Mississippi Embayment, straddling the border between southeastern Missouri and northwestern Tennessee. In late 1811 and early 1812, it produced five earthquakes of magnitudes >6.5, violently shaking the central and eastern United States (CEUS). Its magnitude and recurrence are of concern to today's central United States regions. By considering the effects of local geology, deterministic scenario maps (M_w 7.3 and 7.7) were produced for ground motions intended to simulate the 7 February 1812 event (NM3), which was the largest felt. These maps include spatial estimates of peak ground acceleration and of …

Recent Seismicity And Regional Extension Aithin Southwestern Montana, Usa, Jessica Szkody

Masters Theses

Southwestern Montana has experienced several large damaging earthquakes over the last 100 years, but many minor ones that unveil the nature of the intraplate seismicity. The region in this study is part of two distinct Late Cretaceous tectonic provinces, the Rocky Mountain Foreland Basement (RMFB) and the Cordilleran Fold and Thrust Belt (CFTB). Relationships between the two provinces and their faults show that the focal mechanisms are different. Deep focal mechanisms (between 8 and 10 km) within the RMFB can be placed on a specific fault, with many smaller events falling within the hanging wall. The hypocenters within the hanging …

Quantum Mechanical Derivation Of The Wallis Formula For Π, Tamar Friedmann, C. R. Hagen

Mathematics Sciences: Faculty Publications

A famous pre-Newtonian formula for π is obtained directly from the variational approach to the spectrum of the hydrogen atom in spaces of arbitrary dimensions greater than one, including the physical three dimensions.

Polymer Additives Effects On Structure And Dynamics, Adam Eugene Imel

Doctoral Dissertations

This dissertation presents work that expands the understanding of the effect additives have on the structure and dynamics of a polymer matrix. Polymer additives are molecules, nanoparticles or fibers that are added to a polymer to modify the properties of the host polymer. Due to the vast amount of additives available, our studies were limited to C₆₀ (C60), soft polystyrene nanoparticles, and poly(ethylene oxide).

The first part of this project examined the influence that C₆₀ nanoparticles have on the assembly of polyacrylonitrile using small angle and wide-angle x-ray scattering techniques and viscometry. The addition of C₆₀ (C60) …

System And Process For Upgrading Hydrocarbons, Dennis N. Bingham, Kerry M. Klingler, Joseph D. Smith, Terry D. Turner, Bruce M. Wilding

Chemical and Biochemical Engineering Faculty Research & Creative Works

In one embodiment, a system for upgrading a hydrocarbon material may include a black wax upgrade subsystem and a molten salt gasification (MSG) subsystem. The black wax upgrade subsystem and the MSG subsystem may be located within a common pressure boundary, such as within a pressure vessel. Gaseous materials produced by the MSG subsystem may be used in the process carried out within the black wax upgrade subsystem. For example, hydrogen may pass through a gaseous transfer interface to interact with black wax feed material to hydrogenate such material during a cracking process. In one embodiment, the gaseous transfer interface …