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The Polynomial Chaos Method With Applications To Random Differential Equations, Juan Antonio Licea Salazar

Mathematics Dissertations - Archive

The role of randomness in mathematical models is of paramount importance, with emphasis placed upon the accuracy and reliability of predictions a rational approach is the use of differential equations with random parameters to describe natural phenomena. Well known methods such as Monte Carlo methods and the method of moments have been implemented to approximate the solutions to random differential equations in the last few decades. In this work, analytic solutions to a particular Riccati type dierential equation and discrete delay dierential equation with random coefficients are derived, also, due to its spectral rate of convergence and simplicity, the polynomial …

Numerical Studies For M-Matrix Algebraic Riccati Equations, Weichao Wang

Mathematics Dissertations - Archive

A new doubling algorithm - Alternating-Directional Doubling Algorithm (ADDA) - is developed for computing the unique minimal nonnegative solution of an M-Matrix Algebraic Riccati Equation (MARE). It is argued by both theoretical analysis and numerical experiments that ADDA is always faster than two existing doubling algorithms - SDA of Guo, Lin, and Xu (Numer. Math., 103 (2006), pp. 393-412) and SDA-ss of Bini, Meini, and Poloni (Numer. Math., 116 (2010), pp. 553-578) for the same purpose. A deflation technique is then presented for an irreducible singular M-matrix Algebraic Riccati Equation (MARE). The technique improves the rateof convergence of a doubling …

Dns Study For The Origin Of The Chaos In Late Boundary Layer Transition Over A Flat Plate, Manoj Kumar Thapa

Mathematics Dissertations - Archive

This dissertation is devoted to the investigation of the origin and mechanism of chaos ( asymmetric or disorganized flow) in late boundary layer transition over a flat plate without pressure gradient. This kind of flow not only exists at the very late stage of transition but also is a crucial component for turbulence formation- still not well understood. According to existing theories, the formation of the chaos in late boundary layer transition was considered due to big background disturbances (noises) and use of non-periodic spanwise boundary condition during numerical simulations. It was further assumed that universal coherent structures (ring-like vortices) …

Fracking Up The Future: Recommendations For Hydraulic Fracturing In Gonzales County, Tx, Jennifer Ince, Philip Queller, Devon Rood, Kara Shervanick

Earth and Environmental Geosciences Student Works

Despite its economic appeal, hydraulic fracturing (fracking) has sparked bitter controversy. Allegations of toxic fracking fluids and fracking-induced droughts have made fracking a major public health and environmental concern in the United States. Fracking is dependent on local conditions to a large degree; therefore, we focus on Gonzales County, located within Texas’ Eagle Ford shale region, in order to address county-specific concerns. However, our findings can be applied to help create sustainable practices for fracking in any context. Unfortunately, regulations are limited due to the 2005 Energy Policy Act that prevents federal agencies, including the EPA, from regulating fracking. In …

The Process Of Becoming An Expository Writer, Valerie Vied

Understanding by Design: Complete Collection

This unit examines short non-fiction texts centered on cultural awareness and understanding. Through analyzing model texts students will deduce organizational structures for expository writing and strategies used for effective communication. Through a variety of close reading activities, students will collect a bank of tools to incorporate into their own writing for small open ended writing assignments during the unit and the summative assessment at the end of the unit.

The performance task includes an artistic representation of culture and an expository explaining the significance of the images and symbols chosen. Students will learn to introduce an idea and logically explain …

Randomness, Uncertainty, And Economic Behavior: The Life Of Money In Eighteenth-Century Fiction, Devjani Roy

Theses and Dissertations--English

My dissertation argues that fiction produced in England during the frequent financial crises and political volatility experienced between 1770 and 1820 both reflected and shaped the cultural anxiety occasioned by a seemingly random and increasingly uncertain world. The project begins within the historical framework of the multiple financial crises that occurred in the late eighteenth century: seven crises took place between 1760 and 1797 alone, appearing seemingly out of nowhere and creating a climate of financial meltdown. But how did the awareness of economic turbulence filter into the creative consciousness? Through an interdisciplinary focus on cultural studies and behavioral economics, …

Two-Dimensional Hydrodynamic Modeling Of Two-Phase Flow For Understanding Geyser Phenomena In Urban Stormwater System, Zhiyu S. Shao

Theses and Dissertations--Civil Engineering

During intense rain events a stormwater system can fill rapidly and undergo a transition from open channel flow to pressurized flow. This transition can create large discrete pockets of trapped air in the system. These pockets are pressurized in the horizontal reaches of the system and then are released through vertical vents. In extreme cases, the transition and release of air pockets can create a geyser feature.

The current models are inadequate for simulating mixed flows with complicated air-water interactions, such as geysers. Additionally, the simulation of air escaping in the vertical dropshaft is greatly simplified, or completely ignored, in …

Moisture And Unit Weight Readings From A Complex Impedance Measuring Instrument, Kirk Andrew Jenkins

Theses and Dissertations--Civil Engineering

Complex Impedance Measuring Instruments (CIMI’s) are non-nuclear devices that calculate the dry unit weight and moisture content of soil by means of electromagnetic wave propagation theory. Unlike nuclear based test devices, these devices do not require certification or elaborate maintenance to own and operate. CIMI operation requires a soil specific calibration process where soil moisture and unit weight are correlated to electrical parameters. A new, smaller acrylic mold was developed as an alternative calibration tool to the manufacturer’s recommended mold. Calibrated soil models were generated using manufacturer recommended procedures as well as new procedures involving an acrylic mold. Models were …

Development Of A Multilayered Association Polymer System For Sequential Drug Delivery, Sharath Kumar Chinnakavanam Sundararaj

Theses and Dissertations--Biomedical Engineering

As all the physiological processes in our body are controlled by multiple biomolecules, comprehensive treatment of certain disease conditions may be more effectively achieved by administration of more than one type of drug. Thus, the primary objective of this research was to develop a multilayered, polymer-based system for sequential delivery of multiple drugs. This particular device was designed aimed at the treatment of periodontitis, a highly prevalent oral inflammatory disease that affects 90% of the world population. This condition is caused by bacterial biofilm on the teeth, resulting in a chronic inflammatory response that leads to loss of alveolar bone …

Kentrack 4.0: A Railway Trackbed Structural Design Program, Shushu Liu

Theses and Dissertations--Civil Engineering

The KENTRACK program is a finite element based railway trackbed structural design program that can be utilized to analyze trackbeds having various combinations of all-granular and asphalt-bound layered support. It is applicable for calculating compressive stresses at the top of subgrade, indicative of potential long-term trackbed settlement failure. Furthermore, for trackbeds containing asphalt layer, it is applicable for calculating tensile strains at the bottom of the asphalt layer, indicative of potential fatigue cracking. The program was recently expanded to include both English and international units. A procedure has been incorporated to provide a path to save results in a text …

Pressure Measurement At The Ballast-Tie Interface Of Railroad Track Using Matrix Based Tactile Surface Sensors, Michael T. Mchenry

Theses and Dissertations--Civil Engineering

The pressure distribution at the ballast-tie interface of railroad track plays a key role in overall track support. Failure of the ballast or tie can result from excessive loads that were not designed for, requiring increased maintenance and reducing railroad operating efficiency. Understanding the forces acting on the ballast and tie are required to design higher performance and longer lasting track. To further this understanding, the use of Matrix Based Tactile Surface Sensors (MBTSS) is employed to measure the actual pressure distribution at the ballast-tie interface, characterized by individual ballast particle contact points and non-uniform pressures. The research explores this …

Development Of A Constitutive Model Of Compacted Shales And Determination Of The Effect Of Weathering On Its Parameters, Isabel Cristina Gomez-Gutierrez

Theses and Dissertations--Civil Engineering

Compacted shales cause problems because they tend to degrade with time due to weathering. Degradation results in the shale deteriorating from a hard rock-like material to a soft fine-grained soil mass with lower shear strength and high deformability. Consequently, common problems that occur in embankments constructed with compacted shales include settlement and instabilities. Therefore, accelerating weathering prior to compaction by wetting and breaking down the shales before placement can reduce the deterioration during the service life of the construction. Extensive laboratory testing was performed in order to characterize the mechanical behavior of compacted shales.

Critical State theory is a clever …

Visual Semantic Segmentation And Its Applications, Jizhou Gao

Theses and Dissertations--Computer Science

This dissertation addresses the difficulties of semantic segmentation when dealing with an extensive collection of images and 3D point clouds. Due to the ubiquity of digital cameras that help capture the world around us, as well as the advanced scanning techniques that are able to record 3D replicas of real cities, the sheer amount of visual data available presents many opportunities for both academic research and industrial applications. But the mere quantity of data also poses a tremendous challenge. In particular, the problem of distilling useful information from such a large repository of visual data has attracted ongoing interests in …

Toric Varieties And Cobordism, Andrew Wilfong

Theses and Dissertations--Mathematics

A long-standing problem in cobordism theory has been to find convenient manifolds to represent cobordism classes. For example, in the late 1950's, Hirzebruch asked which complex cobordism classes can be represented by smooth connected algebraic varieties. This question is still open. Progress can be made on this and related problems by studying certain convenient connected algebraic varieties, namely smooth projective toric varieties. The primary focus of this dissertation is to determine which complex cobordism classes can be represented by smooth projective toric varieties. A complete answer is given up to dimension six, and a partial answer is described in dimension …

Regularity And Uniqueness Of Some Geometric Heat Flows And It's Applications, Tao Huang

Theses and Dissertations--Mathematics

This manuscript demonstrates the regularity and uniqueness of some geometric heat flows with critical nonlinearity.

First, under the assumption of smallness of renormalized energy, several issues of the regularity and uniqueness of heat flow of harmonic maps into a unit sphere or a compact Riemannian homogeneous manifold without boundary are established.

For a class of heat flow of harmonic maps to any compact Riemannian manifold without boundary, satisfying the Serrin's condition,

the regularity and uniqueness is also established.

As an application, the hydrodynamic flow of nematic liquid crystals in Serrin's class is proved to be regular and unique.

The natural …

Relative Perturbation Theory For Diagonally Dominant Matrices, Megan Dailey

Theses and Dissertations--Mathematics

Diagonally dominant matrices arise in many applications. In this work, we exploit the structure of diagonally dominant matrices to provide sharp entrywise relative perturbation bounds. We first generalize the results of Dopico and Koev to provide relative perturbation bounds for the LDU factorization with a well conditioned L factor. We then establish relative perturbation bounds for the inverse that are entrywise and independent of the condition number. This allows us to also present relative perturbation bounds for the linear system Ax=b that are independent of the condition number. Lastly, we continue the work of Ye to provide relative perturbation bounds …

Thermobarometry Of Metamorphosed Pseudotachylyte And Determination Of Seismic Rupture Depth During Devonian Caledonian Extension, North Norway, Susan E. Leib

Theses and Dissertations--Earth and Environmental Sciences

Crustal faulting has long been known as the source of shallow seismicity, and the seismogenic zone is the depth (3-15 km) within the crust that is capable of co-seismic slip, largely under brittle conditions. However, some continental seismicity occurs at depths >> 15 km. I performed thermobarometry of mylonitic pseudotachylyte to determine the P-T of a seismogenic extensional fault in the Caledonian Norwegian margin. Two shear zones (Eidsfjord and Fiskfjord) located in northern Norway exhibit brittle extension propagating into the ductile regime of the lower crust as evidenced by the presence of pseudotachylyte. Averages from Eidsfjord (653 ± 38°C and 570 …

Shear-Wave Imaging And Birefringence In A Complex Near-Surface Geological Environment, Ali Z. Almayahi

Theses and Dissertations--Earth and Environmental Sciences

Multiple geophysical and geological data sets were compiled, reprocessed, and interpreted using state-of-the-art signal processing and modeling algorithms to characterize the complex post-Paleozoic geology that overlies the southwestern projection of the Fluorspar Area Fault Complex (FAFC) in western Kentucky. Specific data included 21.5 km of SH-wave seismic reflection, 1.5 km of P-wave seismic reflection, 2 km of electrical resistivity, vertical seismic profiles, Vp and Vs sonic-suspension logs, and 930 lithologic borehole logs. The resultant model indicates three general northeast–southwest-oriented fault zones pass through the study area as southwestern extensions of parts of the FAFC. These fault zones form two significant …

Spatio-Temporal Variability In Groundwater Discharge And Contaminant Fluxes Along A Channelized Stream In Western Kentucky, Ganesh N. Tripathi

Theses and Dissertations--Earth and Environmental Sciences

Spatio-temporal variability in groundwater discharge and contaminant fluxes along a channelized stream in western Kentucky

Surface and groundwater discharges and contaminant fluxes can vary with time and space depending upon the hydrogeological processes and geological setting of the area of interest. This study examined a ~300-m-long, channelized reach of a first-order perennial stream, Little Bayou Creek, in the Coastal Plain of far western Kentucky during the period October 2010–February 2012. Along the study reach, springs discharge groundwater contaminated by the chlorinated organic compound trichloroethene (TCE) and radionuclide technetium-99 (⁹⁹Tc) released as a result of past activities at the …

Distribution And Impacts Of Petroleum Hydrocarbons In Louisiana Tidal Marsh Sediments Following The Deepwater Horizon Oil Spill, Rachel S. Hatch

Theses and Dissertations--Earth and Environmental Sciences

Following the 2010 Deepwater Horizon (DWH) spill, sediment cores were analyzed from marshes at various levels of oiling to determine how deeply oil penetrated sediment in these marsh environments, and if at these sites it had quantifiably affected benthic ecosystems. Minimum mixing depths were determined from penetration of the lithogenic radionuclide ²³⁴Th, which ranged from 0.25 to 4.5 cm. Sediment accumulation rates were determined using ²¹⁰Pb, with verification from ¹³⁷Cs in selected cores. Lead-210 profiles revealed long-term (decadal) mixing. Bay Jimmy, Louisiana was significantly affected by the DWH oil spill, as indicated by total polycyclic aromatic hydrocarbon …

Identifying Risk And Protective Factors Of Preparatory And Non-Preparatory Students In Agricultural Education Programs Of A Rural Kentucky High School, Randy J. Adams

Theses and Dissertations--Community & Leadership Development

Today there is an increased demand for secondary agriculture education programs to prepare students to be college and career ready through a program of study. The purpose of this study was to identify risk and protective factors of preparatory and non-preparatory students within an agriculture education program at Anderson County High School in Lawrenceburg, Kentucky. The results of this study did not determine that there was a difference in risk and protective factors between preparatory and non-preparatory students within agriculture education courses. The study concluded that students among both categories were equally exposed to risks such as family conflict and …

Evaluation Of Motivation And Professional Development Of Curriculum For Agricultural Science Education (Case) Lead And Master Teachers, Miranda Rose Chaplin

Theses and Dissertations--Community & Leadership Development

Curriculum for Agricultural Science Education™ (CASE) is an instructional system of support that provides professional development, curriculum, and assessments to agricultural educators. Through the CASE model, two CASE Lead or Master Teachers facilitate professional development, known as a CASE Institute. This study utilizes three sets of surveys to describe the motivation for CASE certified teachers applying to become CASE Lead and Master Teachers, determine the effectiveness of the professional development provided to Lead and Master Teachers during the Lead Teacher Orientation, and determine the Lead and Master Teachers’ demographic information.

Cofinite Induced Subgraphs Of Impartial Combinatorial Games: An Analysis Of Cis-Nim, Scott M. Garrabrant, Eric J. Friedman, Adam Landsberg

Physics Faculty Scholarship

Given an impartial combinatorial game G, we create a class of related games (CISG) by specifying a finite set of positions in G and forbidding players from moving to those positions (leaving all other game rules unchanged). Such modifications amount to taking cofinite induced subgraphs (CIS) of the original game graph. Some recent numerical/heuristic work has suggested that the underlying structure and behavior of such “CIS-games” can shed new light on, and bears interesting relationships with, the original games from which they are derived. In this paper we present an analytical treatment of the cofinite induced subgraphs associated with the …

Analysis Of Spatial Data, Xiang Zhang

Theses and Dissertations--Statistics

In many areas of the agriculture, biological, physical and social sciences, spatial lattice data are becoming increasingly common. In addition, a large amount of lattice data shows not only visible spatial pattern but also temporal pattern (see, Zhu et al. 2005). An interesting problem is to develop a model to systematically model the relationship between the response variable and possible explanatory variable, while accounting for space and time effect simultaneously.

Spatial-temporal linear model and the corresponding likelihood-based statistical inference are important tools for the analysis of spatial-temporal lattice data. We propose a general asymptotic framework for spatial-temporal linear models and …

James-Stein Type Compound Estimation Of Multiple Mean Response Functions And Their Derivatives, Limin Feng

Theses and Dissertations--Statistics

Charnigo and Srinivasan originally developed compound estimators to nonparametrically estimate mean response functions and their derivatives simultaneously when there is one response variable and one covariate. The compound estimator maintains self consistency and almost optimal convergence rate. This dissertation studies, in part, compound estimation with multiple responses and/or covariates. An empirical comparison of compound estimation, local regression and spline smoothing is included, and near optimal convergence rates are established in the presence of multiple covariates.

James and Stein proposed an estimator of the mean vector of a p dimensional multivariate normal distribution, which produces a smaller risk than the maximum …

Conviction Celerity, Punishment Severity, And Treatment Compliance As Predictors Of Dui Recidivism: Mediation And Moderation Models Of Deterrence, Megan F. Dickson

Theses and Dissertations--Sociology

Driving under the influence (DUI) is one of the most frequently committed offenses in the United States and approximately one-third of DUI offenders are recidivists. Researchers have evaluated multiple DUI prevention approaches, most of which have been rooted in deterrence theory. Recently, the criminal justice system has moved away from deterrence-based approaches and begun employing various forms of rehabilitation to reduce DUI recidivism. This shift in the criminal justice system has lead researchers to begin exploring the effects of rehabilitation on DUI offenders, including an examination of offender compliance with rehabilitation programs. Although each of these areas has been investigated …

A Framework For Understanding The Public's Perspectives Of Mining Applied To The Kentucky Coal Industry, Joshua M. Hoffman

Theses and Dissertations--Mining Engineering

People’s perceptions of mining are heavily based on the media they consume and the messages therein. News outlets ordinarily report on mining only when there is an accident or environmental concern. When messages that the public is exposed to are negative, it is no wonder that there are negative perceptions about mining.

Current public relations campaigns on the behalf of specific companies or select sectors do exist; however, this is often a reactionary move in response to recent shifts in the socio-political environment. The details of these campaigns are often tied up in proprietary information or withheld by public relations …

Characterizing The Variability In Respirable Dust Exposure Using Johnson Transformation And Re-Examining 2010 Proposed Changes To The U.S. Underground Coal Mine Dust Standard, Al I. Khan

Theses and Dissertations--Mining Engineering

Coal workers’ pneumoconiosis (CWP), commonly referred to as black lung, is a chronic lung disease that results from the inhalation and deposition of coal dust in the lungs. While this disease continues to afflict coal miners, its prevalence has steadily declined over three decades since 1970. Based on a voluntary X-ray surveillance program, conducted by the National Institute for Occupational Safety and Health (NIOSH), this downward trend, however, ended in 2000 and has actually begun to rise. The Mine Safety and Health Administration (MSHA) instituted a Comprehensive Initiative to “End Black Lung” to combat the reported upturn in black …

Cavitation Nanobubble Enhanced Flotation Process For More Efficient Coal Recovery, Ahmed S. Sayed Ahmed

Theses and Dissertations--Mining Engineering

Froth flotation is a widely used, cost effective particle separation process. However, its high performance is limited to a narrow particle size range, e.g., between 50 µm and 600 µm for coal and between 10 µm and 100 µm for minerals. Outside this range, the efficiency of froth flotation decreases significantly, especially for difficult-to-float particles of weak hydrophobicity (e.g., oxidized coal).

Nanobubbles integrated into a specially designed column flotation expanded the particle size range for efficient froth flotation as a result of increased probabilities of particle- bubble collision and attachment and reduced probability of detachment.

The major advantages of nanobubble …

Assessing And Mitigating Airborne Noise From Power Generation Equipment, Limin Zhou

Theses and Dissertations--Mechanical and Aerospace Engineering

This dissertation examines the assessment and mitigation of airborne noise from power generation equipment.

The first half of the dissertation investigates the diagnosis and treatment of combustion oscillations in boilers. Sound is produced by the flame and is reflected downstream from the combustion chamber. The reflected sound waves perturb the mixture flow or equivalence ratio increasing the heat release pulsations and the accompanying sound produced by the flame. A feedback loop model for determining the likelihood of and diagnosing combustion oscillations was reviewed, enhanced, and then validated. The current work applies the feedback loop stability model to two boilers, which …