Digital Commons Network^™

Understanding The Instructional Decisions Of Middle-School Mathematics Teachers: Three Case Studies, Alissa Lockwood

Theses and Dissertations

This action research study aimed to explore how middle-school mathematics teachers make instructional decisions in the absence of a required curriculum. While the school site has an adopted textbook, many of the mathematics teachers view this resource as invaluable. Better understanding the decision-making process of mathematics teachers at the school site can provide critical information to better support the teachers. The research question that guided this action research was: How does it seem that middle-school mathematics teachers make instructional decisions? This sequential two-phase qualitative study examined decision-making from a 6^th, 7^th, and 8^th grade mathematics …

Creating Systems Of Professional Learning To Encourage Deep Thinking In Social Studies: A Qualitative Study, Elizabeth Poda King

Theses and Dissertations

This paper describes a problem that developed due to a lack of systems in place to provide professional learning for teachers in social studies. This problem was ignited when revised standards were adopted which shifted from heavy content focus to skills and content. Standards requiring both skills and content encourage student inquiry and promote deep thinking by students through the use of historical evidence. Therefore, the purpose of the improvement science plan-do-study-act (PDSA) cycles was to develop a system of job-embedded professional learning to assist teachers with teaching strategies that use historical evidence to promote deep thinking in social studies …

Expanding Tailored Nanomaterials With Precise Spatial And Morphological Control, Mengxue Zhang

Theses and Dissertations

Multicomponent nanocomposites with precise spatial control are important for diverse fields spanning from energy conversion to optoelectronics and catalysis. Traditional methods using hydrophilic interactions alone are limited to random mixtures when multiple nanoparticle (NP) types are combined. To improve capabilities, a new strategy for polymer micelle design combining orthogonal hydrophilic (H) and fluorophobic (F) interactions to independently control two distinct NP populations was developed.

Initial research aimed at understanding F-interaction adjustments, which further enabled the switchability of FNP distribution states (dispersion vs aggregation) within polymer films through immersion annealing. Next, dual-NP assembly was examined using a diblock poly (H-b-F) where …

The Influence Of Instruction On Underrepresented Stem Leaders On Elementary Students’ Stem Identity And Perceptions Of Stem, Megan Elizabeth Willson

Theses and Dissertations

This action research study explored the influence of exposure to underrepresented STEM leaders on third-grade students’ STEM identity and their interest in STEM careers. Using an integrative STEM approach and guided by both Constructivist Learning Theory and Social Cognitive Career Theory, this convergent mixed methods study consisted of an eight-week intervention with lessons based on different STEM leaders and related activities each week. This eight-week period collected data through weekly researcher field notes, exit tickets and was prefaced and followed by a pre- and post-survey and pre- and post-interviews. Findings from the quantitative data, the Role Identity Survey in STEM …

The Design And Optimization Of Optical Systems For The Detection And Characterization Of Phytoplankton, Caitlyn M. English

Theses and Dissertations

Phytoplankton are among the smallest organisms found in marine and freshwater ecosystems. Despite their small size, phytoplankton play a vital role in sustaining life on Earth as primary producers. Through oxygenic photosynthesis phytoplankton are also responsible for large scale carbon fixation and oxygen production. The distribution of phytoplankton in a given water resource can exhibit a high degree of variability across time and space, and this is in large part due to their varying sensitivities to environmental conditions such as resource availability and grazing by predator organisms. As such, phytoplankton community structure is widely used as an investigative tool for …

Design And Performance Analysis Of Fiber Bragg Grating Temperature Sensor For Industrial Processes Sensing Applications, Paul Stone Stone Brown Macheso S.B.

Tanzania Journal of Engineering and Technology (TJET)

The Fiber Bragg Grating (FBG) sensor has become a widespread sensing device because of its small size, passive design, immunity to electromagnetic interference, and direct ability to measure physical properties like temperature and strain. Recently, femtosecond infrared laser processing and regeneration techniques have resulted in the development of stable high-temperature gratings, which are a powerful tool in smart factories, an aspect of the fourth Industrial Revolution (4IR), and show promise for application in harsh environments like high pressure, high temperature, or ionizing radiation. The development of stable high-temperature gratings that can withstand harsh environmental factors like high temperatures, pressures, and …

Application Of Artificial Neural Network Models For Predicting Diesel And Petrol Prices In The Geographically Sparsed Regions In Tanzania, John M. Kafuku

Tanzania Journal of Engineering and Technology (TJET)

Fuel consumption in Tanzania, mainly diesel and petrol, accounts for 82 percent of the energy consumption in the country, with significant price volatility affecting market stability, availability of fuel, and investment decisions. This study uses an artificial neural network (ANN) with a backpropagating algorithm to predict fuel prices in four regions of Tanzania. Key input parameters include the currency inflation rate (CIR), the petrol fuel inventory (PFI), the diesel fuel inventory (DFI), and the fuel transport costs (FTC). The study selected the 6-10-10-2 ANN structures for Sumbawanga-Rukwa, Mpanda-Katavi, and Mbeya-Mbeya as well as 6-10-9-2 for the Songea-Ruvuma region. The results …

Clustering Mini-Grids To Enhance Power Systems Reliability In Distributed Generation, Santos Kihwele

Tanzania Journal of Engineering and Technology (TJET)

This study investigates the effectiveness of clustering mini-grids as a method to improve the reliability and operational stability of distributed generation systems in remote areas, particularly where renewable energy sources are predominant. As renewable resources like solar and wind are increasingly integrated into mini-grids, these systems face various challenges, particularly in maintaining stable voltage and frequency across interconnected networks. Such issues are compounded by the intermittent nature of renewable energy sources and the lack of extensive communication infrastructure in rural or resource-constrained settings. To address these control challenges, this study applies droop control techniques to two mini-grids in Uganda, utilizing …

Synthetic Inertia Provision For Load Frequency Control In Networks With High Penetration Of Renewable Energy Sources, Paulina Mkoi

Tanzania Journal of Engineering and Technology (TJET)

The integration of renewable energy sources (RESs) such as solar photovoltaic (PV) and wind energy has become a promising solution as the world shifts toward clean energy. Solar PV and wind resources are increasingly replacing conventional synchronous generators, leading to reduced system inertia and increased vulnerability to frequency instability during disturbances. To address this challenge, this study proposes a novel synthetic inertia provision strategy using a battery energy storage system (BESS) integrated alongside solar PV. The proposed method dynamically compensates for the loss of inertia by considering the variability of solar PV output due to changes in irradiance and temperature. …

Thermodynamic Study Of Ligand Coordination On Lead Halide Perovskite Quantum Dots, Bishal Adhikari

Theses and Dissertations

Inorganic lead halide perovskite (ILHP) has been extensively studied in thin films and bulk crystals as promising materials for their photovoltaic and optoelectronic properties. These are stable enough to be prepared as colloidal quantum dots that can be dispersed, deposited and used to achieve quantum confinement; however, selection of the suitable surface passivating ligand remains challenge for long term stability of the colloidal quantum dots. Several ligand coordination chemistries used to achieve greater stability or specific functions: these can be installed at time of synthesis in some cases they can also be installed to preexisting quantum dots by ligand exchange …

Exploring The Aesthetic Representation Of Pinisi As The Basis Of Urban Experience, Imtihan Hanom, I Gede Mugi Raharja, I Made Pande Artadi, I Ketut Sida Arsa

ARSNET

This study explores the aesthetic representation of the Pinisi ship as the basis of an attractive urban space. In particular, it focuses on the aesthetic of a pedestrian bridge in the Sudirman Central Business District (SCBD), Jakarta. The study argues that the visual representation of the Pinisi ship as the epitome of indigenous sailing craft in Indonesia provides a cultural experience that attracts pedestrians, creating relations between the aesthetics of urban space and the overall visitor interest. This study aims to identify the elements of the Pinisi ship that are represented through aesthetic principles and analyse the relationship between representation …

Extracting Metamorphic Histories Utilizing U-Pb Laser Ablation Zircon Geochronology From The Southern Appalachians Crystalline Rocks And Detrital Sediment, Meredith Kay Love Gawai

Theses and Dissertations

The southern Appalachian mountain belt is an accretionary orogen that formed in the southeastern United States through several phases of oceanic subduction and continental collision during the Paleozoic Era and culminated in the formation of the supercontinent Pangaea. Although many U-Pb zircon ages have been collected from the igneous, metaigneous and metasedimentary rocks in the crystalline core of the southern Appalachians, there remain opportunities to better reconstruct the metamorphic and magmatic history of the southern Appalachians through the lens of zircon geochronology. Such data are valuable in identifying genetic relationships between candidate terranes of the orogen. Herein, I present laser-ablation …

The Effects Of Implementing A Mindfulness Program In Two Elementary School Math Classrooms, Sara Lilley

Theses and Dissertations

This action research study examined the effects of utilizing trauma-informed social-emotional learning (SEL) teaching practices in two elementary math classrooms located in a Title 1 public school in North Carolina. The classrooms consisted of one third-grade classroom with 18 students and one fifth-grade classroom with 22 students. These classrooms integrated 10 minutes of mindfulness practice which included direct instruction on calming strategies and breathing techniques. This study worked to help foster a learning environment that supported the academic and mental health needs of the student participants and looked at potential relationships between calming strategies and math assessment data. This study …

Dust And Metals In Distant Galaxies, Fatima Elkhatib

Theses and Dissertations

Interstellar dust causes reddening and dimming of light from background objects. To analyze how different the dust in distant galaxies is compared to dust in nearby galaxies, we look at multiple background quasars and try to fit their spectra with various models for known galaxies that have differing dust grain populations combined with a quasar spectrum template. Through fitting these models, we found that dust in most of the foreground galaxies we analyzed is similar to the SMC bar, a relatively thin area selected from the Small Magellanic Cloud (SMC). However, we note that all the objects we studied did …

Keep Your Head Up: An Examination Of Out-Of-School Literacy Practices In An Intergenerational Family System, Johnnie D. Bryant-Johnson

Theses and Dissertations

The asset-based qualitative study used a phenomenological approach within a Community Cultural Wealth framework to question the practices of an intergenerational family system in the Southeastern United States. The study investigated the family system’s out-of-school literacy practices and the exposure to culturally relevant literature. The study revealed that an elder who actively participated in rearing school-aged children intentionally introduced culturally relevant literature. Similarly, the study revealed that the primary caregivers did engage their school-aged children in conversations related to social justice and introduced them to culturally relevant texts. However, a child's inquiry into the topic initiated primary caregivers’ introduction to …

Symmetries Of Del Pezzo Surfaces, Jonathan Smith

Theses and Dissertations

For each del Pezzo surface X of degree d, the action of the automorphism group Aut(X) on the exceptional curves of X induces a map ρ : Aut(X) → W(R_d), where W(R_d) is the Weyl group of a root system R_d dependent on the degree of X. The image of ρ is well defined up to conjugacy in W(R_d), so we say that a group G acts by automorphisms on a del Pezzo surface X of degree d if a representative of the …

Bayesian Joint Modeling Of Longitudinal Data And Interval-Censored Failure Time Data, Yuchen Mao

Theses and Dissertations

Longitudinal data are a collection of repeated observations of the same subjects at different points in time. Interval-censored data arise when the time to the event of interest for each subject is never exactly observed but known to fall between two consecutive points in time. Joint analysis of longitudinal data and interval-censored failure time data can lead to more accurate estimates compared to separate modeling when the correlation among events of interest or intracluster correlation is present. The aim of this dissertation is to develop efficient and reliable joint analyses of longitudinal and interval-censored failure time data using Bayesian methods. …

Relative Performance Of Mlr, Wlsmv, And Bayes Estimators: An Investigation Using Confirmatory Factor Analysis With Ordinal Data, Tiejun Zhang

Theses and Dissertations

This study investigated the performance of four robust estimators— robust Maximum Likelihood for continuous data (MLR-CON), robust Maximum Likelihood for categorical data (MLR-CAT), robust Weighted Least Squares (WSLMV), and Bayes estimation—in the context of Confirmatory Factor Analysis (CFA) with ordinal data. The objective was to conduct a comprehensive assessment of their efficacy across varied data conditions. A simulation study was designed to comprise conditions that may be encountered with empirical research. The design included 90 cells with two levels of model specification (correct, misspecified), three sample sizes (100, 200, 500), five item distributions (symmetric, moderately asymmetric, moderately asymmetric-alternating, extremely asymmetric, …

Building A Framework For Analyzing Non-Linear And Multidimensional Kinetics, Mainak Dhar

Theses and Dissertations

Many materials exhibit multiple rates of molecular relaxation due to structural complexities. Standard linear and one-dimensional kinetic cannot extract all the necessary dynamic information about these systems. This dissertation contributes to an overarching scheme to develop new non-linear and multidimensional kinetic experiments to obtain this information. The studies span computation and experiments, picosecond to second timescales, and both single-molecule and pulsed-laser kinetics

Single-molecule kinetics experiments yield time series that contain information about unique structural and dynamic properties of materials. However, these time series are noisy, and data analysis is challenging. Parametric methods are computationally intensive and require strong, unverifiable assumptions …

Generalized Sierpiński Numbers And New Irreducibility Criteria On Legendre Polynomials, Robert Scottfield Groth

Theses and Dissertations

A Sierpiński number is an odd positive integer k such that k·2n +1 is composite for all n ∈ Z+. Similarly, a Riesel number is an odd positive integer k such that k · 2n − 1 is composite for all n ∈ Z+, and a Brier number is a number that is both Sierpiński and Riesel. In this dissertation, we consider a generalization of a Sierpiński number and establish their existence by showing, for every fixed A ≥ 2, there are infinitely many odd positive integers k such that the k · an + 1 is composite for every …

Explorations Of Multi-Carboranyl Thiols And Phosphines, Jared Ross Riffle

Theses and Dissertations

In order to ascribe the impact of substituent groups on the bis-ortho-carborane, closo-{C2B10}-closo-{C2B10} multi-cluster system, the first sulfur-containing biscarborane derivatives were synthesized. Biscarborane dithiol, disulfide, bis(methyl)thioether, as well as multiple dithiolate salts were structurally characterized. The exceedingly long C–C bonds and shortened C–S bonds in biscarborane dithiol and its doubly deprotonated dithiolate salts are indicative of significant delocalization of electron density from the sulfur atoms into the cluster. Additionally, a new concept of ligand ambiphilicity is described where, instead of the involvement of only a single center in a ligand, this amphiphilicity relies on the redox behavior of the indirectly …

Photometric Redshifts Of Galaxies In Quasar Fields, Ananthavishnu Santhigiri Unni

Theses and Dissertations

Understanding the gas in and around galaxies is crucial for understanding galaxy evolution. Absorption lines detected in the spectra of background quasars offer a powerful tool to study the gas in and around the intervening galaxies. As a part of an effort to understand how the gas interacts with the stellar component of galaxies, our team previously obtained imaging and spectroscopic observations for a large sample of galaxies using the Hubble Space Telescope (HST), the Very Large Telescope (VLT), and the Atacama Large Millimeter Array (ALMA). This sample includes thousands of galaxies, including many without spectroscopic data. The overall goal …

The Impact Of Microlearning Professional Development On Educator Social And Emotional Competencies And Beliefs About Middle School Students’ Social And Emotional Learning, Kelly M. Abbott

Theses and Dissertations

The COVID-19 pandemic disrupted educational experiences for students with extended school closures and social distancing during the 2020-2021 school year and beyond. School closures, social isolation, and societal issues impacted students and caused mental health challenges as well as behavioral issues in the classroom. This study explored the impact of educator social and emotional competencies (SEC) on social and emotional learning (SEL) in the classroom. Previous research on SEL has found benefits to student’s relationship skills, emotional regulation abilities, and increases in academic achievement. This action research study used a mixed method design to gather data from surveys, interviews, classroom …

Static Characteristics Of An Electromagnetic Three-Phase Reactive Power Sensor For Converting Asymmetric Currents, Timur Urunbayevich Kurbaniyazov

Chemical Technology, Control and Management

This article discusses the processes in the elements and structures of three-phase electromagnetic current sensors used in measuring and controlling three-phase asymmetric reactive power in power supply systems, research models of quantities and parameters, physical mechanisms, and mathematical formulas based on graphical models.

Algorithms For Feature Extraction And Optimisation Of Object Recognition Operator, Hudayberdiev Xakkulmirzayevich Mirzaakbar, Bobomurod Mamitjonovich Tojiboev, Feruza Komiljonovna Samadova

Chemical Technology, Control and Management

This paper deals with the development and analysis of feature extraction and optimisation algorithms for object recognition operators. Different algorithms are used to improve the efficiency of recognition operators in the automatic analysis of remote sensing images. The information model of objects and methods for selecting, extracting and optimising their features have been studied. The issue of extracting important features of objects using spectral, textural and statistical features and constructing optimal operators based on them has also been studied. Effective approaches based on the theory of convex hulls and multidimensional analysis methods have been proposed, taking into account the mutual …

Algorithms For Fast Fire Risk Prediction And Real-Time Data Processing, Mirzoyan Mirzaaxmedovich Kamilov, Tolaniddin Ramziddinovich Nurmukhamedov, Oybek Zokirovich Koraboshev, Bakhodir Saydullayevich Achilov

Chemical Technology, Control and Management

Ensuring fire safety in facilities with high fire risk is one of the pressing problems of modern society. Nowadays, there is a great need for accurate and effective prediction systems for fire prevention and rapid response. Since traditional methods do not provide the ability to quickly analyze and predict in real time, the development of algorithms and modern approaches using modern technologies is of great importance. This article analyzes fire risk prediction algorithms, their principles of operation and effectiveness, and considers methods for assessing and predicting fire risk using Artificial Intelligence (AI), Machine Learning (ML), and Big Data technologies. The …

Detection Of Http Flood Attacks Based On Machine Learning Algorithms, Norbek Karimov, Furkat Rakhmatov, Oybek Xolmuminov

Chemical Technology, Control and Management

This paper analyzes the effectiveness of Random Forest and SVM models for detecting HTTP Flood attacks. Experimental results demonstrate that both models achieve high accuracy. Evaluation was conducted using Precision, Recall, and F1 Score metrics. Additionally, key features of network traffic were extracted through correlation analysis to enable real-time application of the models in attack detection. The findings provide important insights into detecting DDoS attacks using machine learning and improving model performance.

Infusing Aboriginal Perspectives In Cyber Education, John Shannahan, Mohiuddin Ahmed

Research outputs 2022 to 2026

While human factors are important in cyber security, the discipline has largely not explored incorporating indigenous perspectives—or, more specifically, in an Australian context, Aboriginal perspectives—in its curricula. In this paper, we introduce a promising approach for aligning Aboriginal perspectives with the needs of cyber security graduates and incorporating diverse perspectives into cyber degrees. The approach advocates for the centrality of good curriculum design fundamentals: backward design, constructive alignment, and student outcomes. The paper ends by reflecting on challenges and lessons from the first implementation and review of the material. It provides recommendations for other cyber practitioners exploring ways of incorporating …

Filter Relative Notions Of Size With Applications To Semigroup Ramsey Theory, Conner Griffin

Electronic Theses and Dissertations Archive

There are many branches of problems in Ramsey theory which each belong to at least one of a number of subjects: graph theory, number theory and set theory. The successful methods of solution are also varied. Methods of solution have been found relying on probability theory, ergodic theory, dynamical systems theory, algebra and topology. We take the pigeonhole principle as a foundation for the problems in Ramsey theory that we consider. Pigeonhole Principle. Let A be a set with |A| > n for some n ∈ N. Let A = Sn i=1 Ci be a finite partition of A. There is …

Technical Feasibility Analysis Of Green Energy Storage Options And Hornsea Wind Farms, Muhammad Maqbool, Jahir Rizvi, Yeaw Chu Lee, Pablo Borja

School of Engineering, Computing and Mathematics

The global transition towards clean energy sources is becoming essential to reduce reliance on conventional fuels and mitigate carbon emissions. In the future, the clean energy storage landscape, green hydrogen, and green ammonia (powered by renewable energy sources) are emerging as key players. This study explores the prospectives and feasibility of producing and storing offshore green hydrogen and green ammonia. The potential power output of Hornsea one and Hornsea two winds farms in the United Kingdom was calculated using real wind data. The usable electricity from the Hornsea one wind farm was 5.83 TWh/year, and from the Hornsea two wind …