Digital Commons Network^™

Elementary Statistics Instructors' Uptake Of The Teaching Practices Recommended By The American Statistical Association, Marisol Sanchez Cortez

Theses and Dissertations

Previous studies point out there has been a wide gap, in the teaching of mathematics, between the practices recommended in the credential programs and the practices teachers actually do. The purpose of this study is to explore how consistent the teaching practices of introductory statistics instructors are to the recommendations endorsed by the American Statistical Association, to understand what their attitudes to the gap are, and to identify the factors that prevent the instructors from implementing the recommended practices. Data were collected from nine statistics instructors at a state university through survey, classroom observations, and interviews. Findings indicate that the …

Oblivion, Angela V. Scardigno

Theses and Dissertations

I believe I am drawn to work with wood because of genetic reasons. My grandfather was a carpenter. I remember him as a hardworking and busy man. As something inseparable and equally inspiring, I remember his studio which was a small house that was full of creativity and great memories. My grandparents’ house is one of my first memories where I learned to create art and collage. I have started to notice, as I get older, that I am constantly trying to bring back an atmosphere that resembles that warm and safe place of childhood. I have also noticed that …

Glorious Indignities, Benito Salinas Jr.

Theses and Dissertations

The purpose of this creative work is to illustrate the relationship between the identity of the Rio Grande Valley as a whole, corporate control, immigration status, and interpersonal connection. This illustration is achieved through a series of interconnected short stories that culminate in a telling of a real-life event, the prison riot in the Willacy County Correctional Facility. This event has ramification for every character in the novel and for an entire county. This work attempts to simultaneously take a birds-eye view and microscopic examination of the events that lead up to the riot over the course of two and …

An Advanced Approach For Contract Time Determination In Highway Projects, Cuauhtemoc Torres Cantu

Theses and Dissertations

In project management, finishing a project on schedule is one of the most important aspects. The Texas Department of Transportation (TxDOT) has been experiencing delays in some projects that can be accounted to an inaccurate project time estimation process. This research presents the development of a user-friendly and comprehensive computer-based contract time determination system. The enhanced system implements probabilistic scheduling techniques such as Program Evaluation and Review Technique, and Monte Carlo Simulation. Additionally, the application of a lognormal two-point PERT method is explored in this study. The new system proposes the use of a database of production rates based on …

Degree Of Bilingualism, Age, Income And Teacher Ratings Of Giftedness As Potential Predictors Of Dichotic Listening Performance, Francisco J. Sierra

Theses and Dissertations

Bilinguals and gifted individuals have consistently shown distinctive patterns of performance on measures of brain laterality and auditory processing. The purpose of this study is to examine the relationship between bilingualism, teacher ratings of giftedness, and auditory divided attention by comparing children and adults with income partialed out. Child participants from first to fifth grade were included in addition to an adult comparison group. Assessment of bilingualism, auditory divided attention, and giftedness occurred via the Woodcock-Munoz Language Survey-III (WMLS-III), the Dichotic Test of Attention (DITA), and the Hispanic Bilingual Gifted Screening Instrument (HBGSI). The main hypothesis of this study is …

Graphene-Fibers Hybrid Structures As Adsorbents For Heavy Metal Ions In Aqueous Solutions, Dulce C. Capitanachi

Theses and Dissertations

The project focuses on the study of graphene-fiber hybrid structures for adsorption of heavy metal ions in aqueous solutions. Polyvinyl alcohol-based graphene–fiber structures were created using centrifugal spinning and a carbonization process.

Characterization methods of the graphene–fiber hybrid structures (GFHS) include SEM, FTIR, TGA, and EDX. Single-step batch-type adsorption studies were performed to analyze the interaction of Cu (II) and Pb (II) ions onto GFHS surface. Different heavy metal ion concentrations were used, as well as a variation of pH values. Elemental analysis of the adsorbent’s surface after filtration experiments was studied by EDX and spectroscopy to verify the presence …

An Examination Of Professional Learning Community And Teacher Leadership Practices As Perceived By Educators In A District-Wide Plc, Melissa Castaneda

Theses and Dissertations

This quantitative research explored the correlational and causal analysis between professional learning community (PLC) and teacher leadership, as well as the demographic and capacity-building variables and dimensions of the PLCA-R and TLSS instruments as perceived by educators in an identified emergent district-wide PLC (Lopez, 2015) located in south Texas. The overarching question focused on examining the associations between professional learning communities (PLCs) and teacher leadership in South Central ISD (pseudonym).

The findings lend support to the notion that teacher leadership and PLCs are correlated concepts, and further establish that a healthy school culture embraces and empowers teachers by providing professional …

Photocatalytic Degradation Of Simazine Under Visible Light Using Zinc Oxide/Molybdenum Disulfide Heterostructures, Alexandria Castillo

Theses and Dissertations

The photocatalytic degradation of simazine under visible light by using ZnO/MoS2 heterostructures was investigated. Reaction parameters studied to optimize simazine degradation included pH, loading mass of the photocatalyst, and percentage of MoS2 in the heterostructure. pH 2 was the optimal environment for the degradation reaction of all catalysts. A loading mass of 20 mg for each of the ZnO/MoS2 photocatalysts was determined to be the most effective for in the degradation process. The degradation reactions were observed to follow 2nd order kinetics for all photocatalysts at all temperatures. Band gap studies confirmed a lower energy than that of pure ZnO …

Understanding College Readiness Through The Framework For Success In Postsecondary Writing: An Analysis Of Algebra Writing In High School, Gabriel Cerda

Theses and Dissertations

The topic of college readiness in the United States has become increasingly important as the number of students entering post-secondary institutions has continued to increase. Along with efforts to increase college readiness for students in K-12, calls have been made to better define what it means to be college ready and understand what factors play a role in preparing students for a postsecondary education. This study uses the Framework for Success in Postsecondary Writing as a critical lens and method of analysis to understand how the Framework can broaden our understanding of college readiness. This is a mixed methods study …

Learning To Detect Pedestrians By Watching Videos, Andrew Y. Chen

Theses and Dissertations

The field of deep learning has experienced a resurgence in the recent years, particularly resulting with the advent of AlexNet. Supervised learning is currently the most common and practical machine learning method. The struggle with employing supervised learning to approach problems is that it requires training data. Sufficient training data is correlated with performance for deep learning models. The issue is that preparing the training data can be a tedious and labor intensive task, especially on a large scale. The purpose of this paper is to determine how efficient a machine can learn when trained on automatically annotated data. The …

Viability Of Wetland Crops For Use In Treatment Wetlands: Nitrogen Removal From Water And Production Of Food, Andrew Denson Corder

Theses and Dissertations

Treatment wetlands are used to treat wastewater from a variety of sources, but their functionality depends on the macrophytes present therein. To better understand the viability of wetland macrophytes both as sources of food and as agents of nitrogen removal from wastewater, this study quantified plant growth, food production, and nitrogen removal capacity of three common wetland crops as well as three locally dominant graminoid species in a variety of relevant ecological contexts. All six plant species and a control were grown over a ten-week period in three related experiments: (1) under three moisture regimes, (2) with or without competition …

Assessing The Rehabilitation Status Of The Reflooded Bahia Grande, Texas Based On Trace Gas Fluxes, Benthic Macroinvertebrates, And Fish Community Data Along Salinity And Seagrass Gradients, Catherine M. Eckert

Theses and Dissertations

The Bahia Grande is a 6,500-acre tidal basin located at the southernmost tip of Texas. Tidal flow into this coastal estuary was cut off by construction projects in the 1930s, causing the basin to dry up for ~70 years. In 2005, a pilot channel was built to reconnect the estuary to tidal waters, allowing the basin to refill. However, the pilot channel, in addition to other barriers within the basin, do not allow for adequate tidal exchange, leading to intermittent, extreme hypersalinity. Presumably because of the extreme hypersalinity in parts of the Bahia Grande, seagrass beds, which play vital roles …

Association Between Lifetime Adverse Events, Emotion Dysregulation, Posttraumatic Stress Symptoms, Acculturation, And Chronic Pain: A Moderated Mediation Model, Miriam El-Haj

Theses and Dissertations

The association between traumatic experiences and chronic pain is well established. Lesser is known about how acculturation might affect this relation, specifically with Hispanics. In the present study, self-report measures on traumatic experiences, posttraumatic stress symptoms, emotion dysregulation, chronic pain, and acculturation were administered to 140 participants (71.4% females) aged 18–65 years old (M = 35.06, SD = 11.55), to determine whether acculturation moderates the relation between adverse lifetime experiences and chronic pain as mediated by posttraumatic stress symptoms and emotion dysregulation.

Those who were highly acculturated to the U.S. Anglo culture were higher on chronic pain than those who …

Comparison Of Rl Algorithms For Learning To Learn Problems, Adolfo Gonzalez Iii

Theses and Dissertations

Machine learning has been applied to many different problems successfully due to the expressiveness of neural networks and simplicity of first order optimization algorithms. The latter being a vital piece needed for training large neural networks efficiently. Many of these algorithms were produced with behavior produced by experiments and intuition. An interesting question that comes to mind is that rather than observing and then designing algorithms with beneficial behaviors, can these algorithms be learned through a reinforcement learning by modeling optimization as a game. This paper explores several reinforcement learning algorithms which are applied to learn policies suited for optimization.

Application Of Solar Water Heaters For Industrial Use, Lucas T. Atkins

Theses and Dissertations

Solar water heating is a technology that is mainly used for domestic water heating in residential homes. In most applications, the idea is to make a home “off the grid” in that there is no requirement for outside infrastructure or need for energy utility to provide power to this home. This falls in line with the trend of “going green” in an effort to reduce energy use, increase efficiency, or reduce emissions and other harmful byproducts.

This technology can be adapted to reduce the energy costs of industrial manufacturing plants. By eliminating the need for certain sections of a process …

Parametric Study Of Selective Laser Alloying Of Elemental Titanium And Boron Powders Using An Automated Deposition Mechanism, Julian V. Gonzalez

Theses and Dissertations

An automatic powder deposition and leveling mechanism was designed and constructed to assist in surface roughness experiments for titanium-boron samples. Previously developed energy models and x-ray diffraction analysis was used to confirm the creation of titanium diboride samples. To study TiB2 at different energy values, a 52 (2 factors, 5 levels) factorial design was used and carried out under an argon atmosphere, through the AM250 laser melting system. Two experimental runs were carried out and a total of 50 samples were assigned a surface roughness measurement through the Dektak XT profilometer. Graphically and with statistical analysis, the data was determined …

A Study Of Human Balance And Coordination Using A Head Mounted Display, Daniel Gracia De Luna

Theses and Dissertations

Virtual Reality (VR) is growing with new technologies and applications. The new technologies help the user to feel more immersed in virtual environments, but interaction and immersion is an area that has not been well studied. Immersion is the feeling and reaction of users while they are in a virtual environment. This investigation is focused on the study of the human balance and coordination when human subjects are inside a virtual environment. Over 60 subjects are studied under an experiment, where their trajectory is captured and analyzed to identify possible differences or similitudes between male and female subjects.

Comparison Of Eight Remnant Tamaulipan Biotic Province Plant Communities In The Lower Rio Grande Valley Using Multivariate Analyses [Comparación De Ocho Comunidades Vegetales Remanentes De La Provincia Biótica Tamaulipeca El Valle Del Río Grande Usando Análisis Multivariada], Raziel I. Flores

Theses and Dissertations

The Tamaulipan Biotic Province falls within a biogeographic ecotone between temperate North America, the neotropics and the Chihuahuan Desert, and has consequently been defined as “Tamaulipan brushlands.” No quantitative, comparative study has ever been undertaken on the many and varied plant communities that occur in the region. This study compares eight remnant, primary plant communities to test the null hypothesis that the province comprises a single definable vegetation type. Four 50 x 10 m belt-transects were established at each site and woody plants taller than 1 m were recorded to determine species frequency, density, stratification and dominance. Community diversity was …

Developing Multispectral Imaging Techniques To Determine Canopy Coverage And Carbon Storage Of Seagrasses In The Gulf Of Mexico, Ivy Michelle Hinson

Theses and Dissertations

Although seagrass beds provide global ecosystem services, coverage is in rapid decline, with the capacity of seagrasses to sequester carbon of special concern. Current seagrass monitoring methods are labor intensive and may not offer a complete picture of coverage. Remote sensing offers the ability to oversee landscapes but water in coastal environments presents challenges, as the commonly used near-infrared wavelength dissipates in water.

This project aimed to provide reliable methodology to assess seagrass coverage using multispectral imagery taken from an unmanned aerial vehicle and to provide evidence for the link between seagrass coverage and stored belowground carbon for common seagrasses …

Electrostatically Actuated Double Wall Carbon Nanotubes To Include Intertube Van Der Waals Forces, Ezequiel Juarez Ocanas

Theses and Dissertations

This work deals with the amplitude-frequency and amplitude-voltage responses of parametric and primary resonances of electrostatically actuated double-walled carbon nanotubes (DWCNTs). Nonlinear forces acting on the DWCNT are intertube van der Waals and electrostatic forces. Soft AC excitation and small viscous damping are assumed. In coaxial vibration, the outer and inner carbon nanotubes move together (in-phase), maintaining their geometric concentricity; while in noncoaxial vibration, the CNTs move in opposite direction (out-of-phase). Modal coordinate transformation is formulated. The Harmonic Balance Method (HBM) is used to find the free response solutions of the DWCNT. The Reduced Order Model (ROM) method is also …

Essays On Alternative Investments, Chad Kwon

Theses and Dissertations

This dissertation considers the role of cultural traits in the markets for alternative investments. The latter refers to assets that are not traditionally discussed when building a financial portfolio for ordinary investors. These are subject to low turnover, high maintenance costs, and low liquidity for investors. These features distinguish them to be non-typical assets that demand more careful strategy to acquire, maintain, and sell these belongings. Nevertheless, investors are interested in these assets for the dual purposes of building equities and consuming benefits simultaneously during ownership. We focus on two types of durable assets—residential houses and paintings at art auctions—to …

Wildlife Road Mortality Survey Methodologies, Trinity Dale Livingston

Theses and Dissertations

Wildlife mortality due to vehicle collisions is detrimental to species with slower reproduction times, habitat specialists, low density populations, species with large home ranges, or rare species. Vehicle-caused wildlife mortality is an important conservation issue, but before we can ameliorate the effects of road mortalities, we must understand what why it is happening. Wildlife road mortality surveys may be conducted in several ways based on the target species, time available, finances, and safety. Survey methodologies include using accident reports by police and warden agencies, pedestrian road surveys, using citizen scientists, and driving surveys. These methods present a safety risk to …

Empirical Bayes Estimators And Borel-Tanner Distribution, Celestina Ruby Soltero

Theses and Dissertations

The motivation for this paper stems from the role Borel-Tanner (BT) distribution has as the distribution of the total outbreak number in epidemics modeled by branching processes. We briefly review Borel-Tanner distribution and its applications. In Chapter II we outline the Bayes decision problem, a construction for an Empirical Bayes (EB) estimator proposed by Liang [9] and discuss risk analysis. In Chapter III, the importance of randomization addressed and a classical construction of a monotonized EB estimator proposed by Houwalingen [14] is outlined. Lastly in Chapter IV we use R software to perform a Monte Carlo simulation and conduct a …

Antecedents And Consequences Of Leaders’ Security Orientation, Joseph J. Simpson

Theses and Dissertations

Organizations’ leaders are responsible for ensuring that firms’ proprietary assets are protected from expropriation. Firms are increasingly targets of large-scale proprietary assets breaches that jeopardize their ability to financially benefit from their innovation activities. Some firms have proactively built capabilities that allow them to protect their proprietary assets, while leaders are more security oriented and therefore do more to protect their organizations from proprietary assets breaches? Current research on leaders’ role in the protection of proprietary assets is lacking at the strategic level because most studies on organizational security have emphasized employee-level behaviors (e.g., da Veiga & Eloff, 2010, Lee, …

Analysis Of The Cnn Algorithm In Target Recognition By Using The Mstar Database, Ligang Zou

Theses and Dissertations

With the rapid development of artificial intelligence technology and the emergence of a large number of innovative theories, the concept of deep learning is widely used in object detection, speech recognition, language translation and other fields. One of the important practices is target recognition in SAR images. Although it shows certain effectiveness in some researches, when using deep learning algorithm, there are still many problems that have not yet been solved. For example, people do not have a good understanding of how convolution works and the impact of convolution on the algorithm, although convolution works well in the CNN algorithm. …

Enhancing Transport In Classical And Quantum Systems Using Non-Hermiticity, Fatemeh Mostafavi

Theses and Dissertations

Non-Hermiticity, the presence of gain and loss in the structures, provides a flexible platform to utilize the wave propagation in classical and quantum system. Here in this thesis by using this advantage we aim to enhance the transport in both realms.

Teen Dating Violence In A Sample Of High School Students In The Rio Grande Valley, Gabriela Ontiveros

Theses and Dissertations

This study analyzes the extent of teenage dating violence (TDV) perpetration and victimization among a sample of high school students in the Rio Grande Valley and its relationship with the occurrence of Adverse Childhood Experiences (ACEs) and exposure to interparental violence. Two hundred and twenty participants out of 426 were eligible for analyses. Rates of male and female physical abuse perpetration and victimization were similar although females reported significantly higher perpetration and males higher victimization rates. Regression analyses indicated that females exposed to interparental violence reported higher rates of overall TDV perpetration and physical abuse perpetration.

Females with higher occurrences …

2-Hyponormality On Unilateral Weighted Shifts, Juan G. Benitez

Theses and Dissertations

Given the concept of a normal operator, several weaker notions have been proposed in order to extend the properties of normal operators to a wider range of operators. One such notion is that of k-hyponormal operators. In this document, we focus our attention on the 2-hyponormality of weighted shift operators over a discrete Hilbert space. It will be shown that if a certain relation between the weights α = ( α0, α1,...) of a weighted shift Wα is satisfied, then the 2-hyponormality of Wα implies the hyponormality of Wαm for any m = 2, 3,....

Energy Harvesting Techniques To Power Onboard Railway Bearing Condition Monitoring Systems, Jacob Nathaniel Bensen

Theses and Dissertations

Limitations of the standard wayside hotbox detection system as a method to identify failing railway bearings severely inhibit the reliability and safety of rail transport. An onboard bearing condition monitoring system would address and ameliorate the issues present in the current detection system. The onboard system would provide more frequent and reliable information regarding bearing condition. For the system to succeed in reducing maintenance time and preventing bearing failure, a method of providing the system with sufficient energy to power its instrumentation is necessary. The instrumentation location environment poses a significant challenge. The device must be placed on the steel …

A Search For A High-Order Excitation Of Surface Phonon Polaritons On Silicon Carbide Metasurfaces, Md Litan Ali

Theses and Dissertations

Metasurfaces promise a control of light in free and confined spaces like optical waveguides using subwavelength-scale nanostructures. In this work, we experimentally investigate a variety control of light in more confined spaces which is localized surface waves of light. A control of surface waves has been challenged because of a lack of efficient nanostructures. For example, conventional and widely used metallic nanostructures have a high coupling efficiency of light due to free charge carriers but the charge carriers induce a high optical power loss. We recently designed and fabricated metal/dielectric multilayer aperture on ionic crystal, which shows a strong resonance …