Digital Commons Network^™

The Impacts Of Using Geogebra On Students’ Perceptions And Achievement In Learning Trigonometric Ratios, Robert Carlos Trejo

Theses and Dissertations

GeoGebra, a dynamic mathematics software, was used to study high school students’ perceptions and achievements in learning trigonometric ratios. The study addresses a critical gap in the literature concerning the use of GeoGebra for understanding trigonometric concepts, particularly in fostering conceptual clarity and problem-solving skills. Rooted in a constructivist pedagogical framework, the research examines how GeoGebra facilitates interactive and exploratory learning environments that encourage active student engagement and deeper comprehension of trigonometric ratio principles.

The study employed a quantitative approach to evaluate the efficacy of GeoGebra. Quantitative data focused on student achievement in solving trigonometric ratio problems through pre- and …

Density Functional Theory And Machine Learning Analysis Of C—C Reductive Coupling From Terminal Cyanido And Cyaphido Complexes, Roberto Magdiel Escobar

Theses and Dissertations

Carbon–carbon (C–C) bond activation has gained increased attention as a direct method for the synthesis of pharmaceuticals and industrial chemistry. Due to the thermodynamic stability and kinetic inaccessibility of the C–C bonds, however, activation of C–C bonds by homogeneous transition-metal catalysts under mild homogeneous conditions is still a challenge. Most of the systems in which the activation occurs either have aromatization or relief of ring strain as the primary driving force. The activation of unstrained C–C bonds of phosphaalkynes does not have this advantage. This study employs Density Functional Theory (DFT) calculations using the Gaussian16 package to elucidate and compare …

Feasibility Study On Microwave Glucose Level Monitoring, Ricardo Cepeda

Theses and Dissertations

Diabetes management heavily relies on regular blood glucose monitoring, which traditionally involves invasive techniques. In recent years, significant research has been directed towards developing non-invasive glucose monitoring methods, particularly using electromagnetic waves. This study explores the feasibility of detecting blood glucose levels non-invasively by measuring the resonant frequency shifts of an antenna, influenced by the dielectric properties of blood. Microwave measurement techniques have garnered attention due to their ability to safely penetrate human tissue and detect biochemical markers like glucose. While previous studies have established a link between glucose concentration and dielectric properties, many techniques suffer from poor sensitivity or …

Primary And Secondary Resonances Of Fringe Effect Electrostatically Actuated Mems Cantilever Resonators, Miguel Armando Martinez

Theses and Dissertations

The nonlinear dynamics of micro-electromechanical system (MEMS) cantilever resonators actuated by the fringe field at parametric and primary resonances are studied. Three models are used based on different descriptions of the system capacitance. In the fringe and capacitance models, the electrostatic force due to the parallel-plate capacitance is neglected due to a hole in the ground plate (removes overlapping area). The SolidWorks model is based on numerical capacitance simulations performed on SolidWorks using EMS. All three models that approximate the fringe field capacitance are compared with one another. The Method of Multiple Scales (MMS) and Reduced Order Model (ROM) up …

Understanding The Influence Of Traffic And Noise On The Wildlife Community Surrounding Fm106 And Sh100 In South Texas, Anna Rose Mehner

Theses and Dissertations

In South Texas, highways create landscape fragmentation, habitat degradation, and result in wildlife vehicle collisions. Vehicle collisions are the highest known cause of mortality of the endangered ocelot (Leopardus pardalis), which led Texas Department of Transportation to install nine wildlife crossing structures (WCS) on Farm-to-Market 106 and five on State Highway 100. These highways are along Laguna Atascosa National Wildlife Refuge, which is the location of the southernmost breeding population of ocelots in the United States. Many other wildlife species including bobcat (Lynx rufus) and coyote (Canis latrans), are present along these highways and …

Structure Modifications And Alternative Monitoring Designs Of Wildlife Road Mitigation Structures, Madison T. Nadler

Theses and Dissertations

Wildlife mitigation structures are designed to keep animals off roadways while providing them safe passage to the other side and not impeding traffic flow. Camera traps are commonly used to assess the success of these mitigation structures, but there are downfalls to both the methods and structures. Alternative mitigation structure designs are needed to better prevent wildlife from accessing roadways in areas where they should be deterred. Additionally, traditional camera trapping methods do not accurately capture the full wildlife communities that may be utilizing these structures and other survey methods are needed, specifically aimed at small mammals, amphibians, and reptiles. …

Technical Potential And Challenges For Agrivoltaic Development In Nigeria, Ifeoluwa Ezekiel Babarinde

Theses and Dissertations

The co-location of agriculture and solar photovoltaic (PV) infrastructure, known as agrivoltaics, is an increasingly popular practice that offers co-benefits like reduced plant drought stress and improved yields of shade-tolerant crops, particularly in water-scarce agricultural regions. Despite its global growth, knowledge on the technical potential, opportunities, and challenges for agrivoltaic development remains limited in the Global South. Here we address this knowledge gap for Nigeria, Africa’s most populous country, by identifying high-potential regions based on the premise that agrivoltaic co-benefits are generally most pronounced in arable lands with both high solar irradiation and water stress. We find that northern regions, …

Guiding Wildlife: Evaluating Wildlife Exit Designs And Sensor Lights For Safer Highways In South Texas, Rupesh Maharjan

Theses and Dissertations

Roadside exclusionary fencing is more prevalent on highways to prevent wildlife-vehicle collisions. Although it can mitigate wildlife road mortality by limiting their access to the road, it can also create a barrier for wildlife stranded within the right-of-way. In State Highway 100 of Texas, the Texas Department of Transportation installed ten wildlife exits to allow wildlife to escape the fenced roadway, and a pair of sensor lights on 13 wildlife guards (WGs) to scare off target species (bobcats and coyotes) from crossing the guards and accessing the roadway. In this study, the effectiveness of three wildlife exit (WE) designs were …

Implementing Organic Fertilization Practices To Improve Aloe Vera Growth And Soil Health In The Lower Rio Grande Valley, Isaiah Edward Jaramillo

Theses and Dissertations

Aloe vera (L.) (Aloe) Burm. f., is valued for its applications across the cosmetic, medicinal, and food industries due to its leaf gel. In the aloe industry, the extraction of gel from leaves generates significant quantities of organic waste, which presents an opportunity to repurpose this material as an amendment in aloe cultivation. While Aloe is renowned for its resilience, understanding the feasibility of using these organic shavings as a soil fertility amendment in aloe production is critical. This research aims to identify sustainable fertilization methods for Aloe that can maintain and/or improve crop yield while enhancing soil health. This …

Proof Of Concept: Simulating Drone Tracking In A Border Security Context, Jose Ruben Espinoza

Theses and Dissertations

Worldwide availability of drone technology has risen to unprecedented levels within the past century due to its commercial availability. While there has been various positive applications of such technology, it has additionally found usage within security critical contexts. Specifically, there have been reports of illegal drug smuggling along the Mexico-United States border in which quadrocopter based drones have been used. Within our research we aim to showcase, as a proof of concept, that autonomous drone technology can be leveraged within a defensive approach via the usage of reinforcement learning and object detection for security critical contexts. To promote the importance …

A Nursery Study Of The Interplay Between Soil Texture, Rooting Space, And Nurse Plants On Seedling Growth And Root Development In Woody Species Of Tamaulipan Thornscrub, Lance I. Santos

Theses and Dissertations

Reforestation attempts in semi-arid regions are plagued with seedling mortality. Blanket greenhouse practices may not be optimal, in addition, commensalism interactions between nurse plants are considered. To better understand the effects of soil texture and nurse plant interactions on growth and drought tolerance, two experiments were developed. For soil texture, Border palo verde seedlings were grown in different-sized plant bands with three soil types. To observe the effects of nurse plants, an experiment using guayacan, was developed using Texas Ebony, as a leguminous nurse plant. Plants were also exposed to a drought experiment. The results suggest that some soil textures …

Evaluation Of Polymerization Condition Reactions Of Methyl Vinyl Ketone For Hydrogen Storage, Rituborna Ghosh

Theses and Dissertations

Hydrogen is widely regarded as one of the most promising clean alternative fuel sources; however, its widespread adoption has been hindered by significant challenges related to storage and transportation. Various storage methods have been proposed and developed, with continuous advancements being made to address these issues. Among the most effective solutions is the utilization of polymers, which serve as safe and efficient hydrogen storage media. This work investigated the polymerization of methyl vinyl ketone using different ratio of monomer: initiator and monomer: crosslinker using N,N′-methylenebisacrylamide (MBA) as crosslinker and ammonium persulfate (APS) as initiator in a free radical polymerization mechanism. …

Theoretical Insights And Analysis Into Luneburg Lens, Aram Flores

Theses and Dissertations

Advancements in wireless communications necessitate innovative antenna designs for radar systems and satellite communications. The Luneburg lens, theorized by Rudolf Luneburg in 1944, is a gradient-index lens capable of focusing electromagnetic waves onto a point on its surface, offering potential improvements in antenna gain and performance. Access to the lenses, courtesy of Assured Space Access Incorporated, enabled me to research the lenses response, and specific design details remain confidential. Practical assessments of 3D-printed Luneburg lenses of varying sizes are limited, including factors such as lens alignment and focal point offset. This study investigates the performance of 6-inch and 13.25-inch Luneburg …

Student Loan Debt Disparity Among White, African American And Hispanic Women: A National View, Arnoldo Trejo

Theses and Dissertations

Published research into the student loan debt problem reveals a disproportionate impact on underrepresented groups within higher education, notably Hispanics, African Americans, and women students. Research on student loan debt underscores that lower-income and first-generation college students are significantly more affected when compared to their higher-income counterparts. The escalating trends in student loan debt are forcing college-going students in the United States to postpone major life events such as homeownership, marriage, and starting a family. The burden of high student debt negatively influences the accumulation of family wealth, including critical aspects such as home ownership, retirement savings, investments, and other …

Online Learning Communities And Secondary Educators' Tech-Enhanced Instructional Practices: A Correlational Study, Oscar R. Carrera

Theses and Dissertations

This correlational study investigated how secondary educators' engagement in online learning communities relates to their tech-enhanced instructional practices, a relationship that gained importance following the COVID-19 pandemic's acceleration of educational technology adoption. Through the lens of Keller's ARCS Model of Motivation (Keller, 1987) and demographic analysis, the research examined three key aspects: the relationship between community engagement and tech-enhanced instructional practices, demographic predictors of engagement, and correlations between ARCS motivational components and engagement. Data collected through a cross-sectional survey of 115 secondary educators revealed a statistically significant moderate positive correlation between engagement in online learning communities and tech-enhanced instructional practices. …

Enhancing Educator Technology Skills In The Digital Age: A Comparative Analysis Of Video And Screenshot Microlesson Professional Development, Brittni Knebel Kalich

Theses and Dissertations

This study examined video and screenshot microlesson formats as a technology professional development for enhancing educators’ technology skills. As educators face increasing demands for technology proficiency in the twenty-first century classroom, this study was conducted to help address a need for further investigation into whether screenshot or video microlessons can serve as effective PD tools for teachers (Bowman, Vongkulluksn, Jiang, and Xie, 2020). Using a comparative design, this study evaluated three groups: one receiving video microlessons, another receiving screenshot-based microlessons, and a control group receiving no lesson. Data were collected through post test scores (multiple choice questions), a Likert-scale survey, …

Bayesian Lasso Regularized Quantile Regression And Its Applications, Priscilla Kissi-Appiah

Theses and Dissertations

Since the pioneering work of (Koenker and Bassett Jr 1978), quantile regression has been a popular regression technique that helps researchers investigate a whole distribution of the response variable. In addition, due to the quantile check loss function, it is robust against outliers and heavy-tailed distributions of the response variable and can provide a more comprehensive picture of modeling via exploring the conditional quantiles of the response variable. In this research, we study the lasso regularized quantile regression from a Bayesian perspective. We develop an efficient sampling algorithm to generate posterior samplings for making posterior inference by using a location-scale …

Teachers’ Perceptions On The Impact And Effectiveness Of Certification Programs In Preparing And Retaining Educators, Teresa De Jesus Padilla

Theses and Dissertations

Mathematics is integral to STEM fields, making math critically important for the stability and development of the nation. As a result, mathematics teachers have a crucial role in our society. A role whose importance needs the necessary support to accomplish its numerous responsibilities. However, research indicates that certification routes—traditional and alternative—often fail to adequately prepare math teachers for the challenges they face, leading to high turnover rates. This study explores the impact of these certification routes on teachers’ abilities to support student achievement, address diverse learning needs, and manage additional duties. Surveying secondary math teachers in the Rio Grande Valley, …

Examining Hispanic Beginning Farmers And Ranchers In The Rio Grande Valley Through A Community Capitals Framework, Perla Kimberly Schrock

Theses and Dissertations

While existing literature addresses the experiences of beginning farmers and ranchers (BFR), there is a notable gap in research focused on Hispanic beginning farmers and ranchers (HBFR). This study aimed at exploring the unique experiences of HBFR in a predominantly Hispanic region, the Rio Grande Valley (RGV), employed the Community Capitals Framework (Flora et al., 2016). I conducted 16 semi-structured interviews with HBFR and local nonprofit organizations and federal employees, complemented by participant observations. Through thematic and content analysis of the interview transcripts, findings revealed valuable insights into the livelihoods of HBFR. Despite HBFR facing significant challenges, this study demonstrated …

Leveraging A Community Of Practice To Advance Stem Education Reform And Promote Teacher And Student Self-Efficacy, Ruth Renee Colyer

Theses and Dissertations

This dissertation examined the impact of the CREST-MECIS community of practice on K-12 STEM teachers and undergraduate and graduate students, addressing the urgent need for innovative approaches in science education to meet the challenges of the 21st century. The study was grounded in response to three primary problem statements: 1) the significant learning losses and socio-emotional challenges stemming from the COVID-19 pandemic, 2) the inadequacy of traditional instructional methods in post-pandemic classrooms, and 3) the need for culturally relevant and inclusive teaching practices that acknowledge students’ lived experiences. Data were collected through pre- and post-interviews, survey analyses, and qualitative feedback …

Challenges And Strategies In Science Learning: A Thematic Review And Meta-Analysis, Angelica A. Guanzon

Theses and Dissertations

This study thoroughly explores the relationships between the challenges faced by students and the alternative problem-solving strategies employed. By analyzing these connections, the research aims to offer a comprehensive understanding of how students address difficulties in science learning and the adaptive strategies they apply. Through this research, teachers can gain valuable understanding in adapting learning resources that successfully address diverse needs of students. By identifying specific challenges and correlating effective strategies, targeted interventions are designed to enhance the overall science learning experience. The study emphasizes the importance of a dynamic and adaptable teaching approach that caters to the evolving landscape …

Exploring 3rd-8th Grade Teachers’ Conceptions Of The Nwea Map Assessment And The Relationship On Grade Level, Content Area, And Students’ Academic Growth, Dymphna Jewelle Canales

Theses and Dissertations

In education, assessment helps shape teaching practices and student outcomes, as it influences how teachers perceive their roles, approach instruction, and engage with students. This study investigated 3rd-8th grade English Language Arts and mathematics teachers' conceptions of the NWEA MAP Growth assessment, focusing on four key factors: (1) improvement for teaching and learning, (2) school accountability, (3) student accountability, and (4) assessment irrelevance. The research examined the relationship between teachers' conceptions and variables such as grade levels, content areas, and students' academic growth as measured by NWEA MAP scores. Using a descriptive correlational design, data were collected from 61 teachers …

Machine Learning Optimized Depolymerization Of Pet (Polyethylene Terephthalate) Via Glycolysis, Mehwash Aamir

Theses and Dissertations

Over 90% of the approximately 1 million PET bottles sold every minute end up in landfills or oceans, where they can persist for centuries. Plastic pollution urgently needs sustainable management and recycling solutions to mitigate the environmental impact of PET waste. From all techniques to recycle plastic waste, catalytic glycolysis stands out for its rapid reaction time, high monomer yields, lower costs, and enhanced durability.

In this work glycolysis of PET was evaluated under microwave conditions using 1,5,7-Triazabicyclo [4.4.0] dec5-ene (TBD) and 1,8-Diazabicyclo [5.4.0] undec-7-ene (DBU) as catalysts, being DBU as the best catalyst for further analysis. The effect of …

Microwave-Assisted Green Synthesis Of Spiroindolinopyranopyrazoles, Esther Owusu

Theses and Dissertations

Green Chemistry, usually known as sustainable chemistry, is widely implemented worldwide to safeguard human health and the environment. Recent investigations in organic synthesis and chemical transformation have demonstrated that green chemistry techniques are significantly reducing both chemical waste and reaction time. In order to fulfill this ecological requirement, it is crucial to lessen the utilization of perilous solvents and noxious chemicals, while also creating innovative reaction methods that decrease the production of trash. The implementation of such methodologies can greatly enhance the field of green chemistry. A more environmentally friendly synthetic method was utilized to generate spiro chemicals and their …

Enhancing Student Learning Of The Physics Of The Human Eye In The Context Of Computer Vision Syndrome During Covid-19, Liang Zeng, Guang Zeng

Physics & Astronomy Faculty Publications

No abstract provided.

The Temperature Versus Orbital Period Relation Of Am Cvns: Insights From Their Donors, Colin W. Macrie, Liliana Rivera Sandoval, Yuri Cavecchi, Tin Long Sunny Wong, Manuel Pichardo Marcano

Physics & Astronomy Faculty Publications

We studied the spectral energy distribution of 22 known AM CVns with orbital periods (Porb) larger than 35 minutes using multiwavelength public photometric data to estimate the effective temperature of the accreting white dwarf. We find an infrared (IR) excess in all systems when compared to a single blackbody, both when the disk should be extended and when it should be truncated by the accretor's magnetic field. This suggests a dominant contribution from the donor to the IR flux. When fitting two blackbodies, the temperature of the hot component decreases with Porb, as expected by evolutionary models. …

Correlates Of Creativity And Elementary School Students’ Perceptions Of Individual And Sociocultural Factors, Seokmin Kang, Hye-Sook Park

Teaching and Learning Faculty Publications

The study investigated the relationships between individual and sociocultural factors and students’ creativity based on a sociocultural perspective. The participants are 7,324 fifth graders from 242 schools obtained from the Korean Educational Longitudinal Study 2013. Through multilevel modeling, student gender, self-regulation behaviors, academic achievement, extrinsic motivation, and perceived parenting style at level 1, and school characteristics such as teacher’s teaching methods, students’ relationship with their teacher, and their teacher’s academic pressure at level 2 were incorporated. The final model incorporating both level 1 and level 2 variables showed that the most significant variable related to students’ creativity was self-regulation, followed …

Anomaly Detection Using Unsupervised Machine Learning Algorithms: A Simulation Study, Edmund F. Agyemang

School of Mathematical & Statistical Sciences Faculty Publications

This study presents a comprehensive evaluation of five prominent unsupervised machine learning anomaly detection algorithms: One-Class Support Vector Machine (One-Class SVM), One-Class SVM with Stochastic Gradient Descent (SGD), Isolation Forest (iForest), Local Outlier Factor (LOF), and Robust Covariance (Elliptic Envelope). Through systematic analysis on a synthetically simulated dataset, the study assessed each algorithm’s predictive performance using accuracy, precision, recall, and F1 score specifically for outlier detection. The evaluation reveals that One-Class SVM, Isolation Forest, and Robust Covariance are more effective in identifying outliers in the synthetic simulated dataset, with Isolation Forest slightly outperforming the other algorithms in terms of balancing …

On Representations Of The Super-Yangian Of The Queer Lie Superalgebra, Elena Poletaeva

School of Mathematical & Statistical Sciences Faculty Publications

Let Q(n) be the queer Lie superalgebra. We determine conditions under which two 1-dimensional modules over the super-Yangian of Q(n) can be extended nontrivially. We describe the dual modules of the simple finite-dimensional modules over YQ(1) . We use these results to describe blocks in the subcategory of finite-dimensional YQ(1) -modules admitting the zero generalized central character.

Modelling Tinnitus Functional Index Reduction Using Supervised Machine Learning Algorithms, Edmund F. Agyemang

School of Mathematical & Statistical Sciences Faculty Publications

This study aims to model the reduction in the Tinnitus Functional Index (TFI) utilizing supervised machine learning algorithms, focusing primarily on Ordinary Least Squares (OLS), K-Nearest Neighbor (KNN), Ridge, and Lasso regressions. Our analysis highlighted Group, ISI, and SWLS as significant predictors of TFI reduction, identified through the best subset selection and confirmed by both forward and backward selection criteria in the OLS regression. Notably, the shrinkage methods, Ridge and Lasso regressions, demonstrated superior performance compared to OLS and KNN, with the Ridge regression presenting the smallest test mean square error (MSE) of 318.30. This finding establishes the Ridge regression …