Digital Commons Network^™

Vocabulary Learning Strategies Used By Esl Saudi Students In The United States, Alya Abdullah K. Suliman

Dissertations

Problem

The purpose of this study was to discover the preferred and used English vocabulary learning strategies of Saudi Arabic-speaking English as a Second Language (ESL) learners. In the light insufficient empirical and theoretical studies exploring the complex structure of vocabulary learning by Arabic-speaking ESL learners, this study investigated which strategies students viewed as significant in assisting them in learning new English vocabulary. Finally, the study sought to identify Saudi Arabic-speaking student attitudes toward and motivations for learning English as a second language; and whether these attitudes influenced which vocabulary learning strategies they preferred and used commonly.

Method

The research …

Adequately Generating Captions For An Image Using Adaptive And Global Attention Mechanisms., Shravan Kumar Talanki Venkatarathanaiahsetty

Dissertations

Generating description to images is a recent surge and with latest developments in the field of Artificial Intelligence, it can be one of the prominent applications to bridge the gap between Computer vision and Natural language processing fields. In terms of the learning curve, Deep learning has become the main backbone in driving many new applications. Image Captioning is one such application where the usage of Deep learning methods enhanced the performance of the captioning accuracy. The introduction of the Encoder-Decoder framework was a breakthrough in Image captioning. But as the sequences got longer the performance of captions was affected. …

Improving A Network Intrusion Detection System’S Efficiency Using Model-Based Data Augmentation, Vinicius Waterkemper Lodetti

Dissertations

A network intrusion detection system (NIDS) is one important element to mitigate cybersecurity risks, the NIDS allow for detecting anomalies in a network which may be a cyberattack to a corporate network environment. A NIDS can be seen as a classification problem where the ultimate goal is to distinguish between malicious traffic among a majority of benign traffic. Researches on NIDS are often performed using outdated datasets that don’t represent the actual cyberspace. Datasets such as the CICIDS2018 address this gap by being generated from attacks and an infrastructure that reflects an up-to-date scenario.

A problem may arise when machine …

An Evaluation On The Performance Of Code Generated With Webassembly Compilers, Raymond Phelan

Dissertations

WebAssembly is a new technology that is revolutionizing the web. Essentially it is a low-level binary instruction set that can be run on browsers, servers or stand-alone environments. Many programming languages either currently have, or are working on, compilers that will compile the language into WebAssembly. This means that applications written in languages like C++ or Rust can now be run on the web, directly in a browser or other environment. However, as we will highlight in this research, the quality of code generated by the different WebAssembly compilers varies and causes performance issues. This research paper aims to evaluate …

A Hybrid Neural Network For Stock Price Direction Forecasting, Daniel Devine

Dissertations

The volatility of stock markets makes them notoriously difficult to predict and is the reason that many investors sell out at the wrong time. Contrary to the efficient market hypothesis (EMH) and the random walk theory, contribution to the study of machine learning models for stock price forecasting has shown evidence of stock markets predictability with varying degrees of success. Contemporary approaches have sought to use a hybrid of convolutional neural network (CNN) for its feature extraction capabilities and long short-term memory (LSTM) neural network for its time series prediction. This comparative study aims to determine the predictability of stock …

Identifying Significant Features For Player Evaluation In Nfl Comparing Anns And Traditional Models, Ronan Walsh

Dissertations

The evaluation of player performance in sports is popular and important in modern sports, enabling teams to use real data in the construction of their rosters. This dissertation proposes to apply machine learning algorithms to predicting the player evaluations from a leading NFL analytics company who use a combination of statistics and expert evaluation. In addition, it will investigate what features are significant in the evaluation of a position. Data for the dissertation is obtained from multiple online sources - Pro Football Reference and Pro Football Focus (the the NFL analytics company). These data sets are combined and analysed before …

Identifying Roles Of Software Developers From Their Answers On Stack Overflow, Dean Power

Dissertations

Stack Overflow is the world’s largest community of software developers. Users ask and answer questions on various tagged topics of software development. The set of questions a site user answers is representative of their knowledge base, or “wheelhouse”. It is proposed that clustering users by their wheelhouse yields communities of similar software developers by skill-set. These communities represent the different roles within software development and could be used as the basis to define roles at any point in time in an ever-evolving landscape of software development. A network graph of site users, linked if they answered questions on the same …

Can Generative Adversarial Networks Help Us Fight Financial Fraud?, Sean Mciver

Dissertations

Transactional fraud datasets exhibit extreme class imbalance. Learners cannot make accurate generalizations without sufficient data. Researchers can account for imbalance at the data level, algorithmic level or both. This paper focuses on techniques at the data level. We evaluate the evidence of the optimal technique and potential enhancements. Global fraud losses totalled more than 80 % of the UK’s GDP in 2019. The improvement of preprocessing is inherently valuable in fighting these losses. Synthetic minority oversampling technique (SMOTE) and extensions of SMOTE are currently the most common preprocessing strategies. SMOTE oversamples the minority classes by randomly generating a point between …

Performance Comparison Between A Distributed Particle Swarm Algorithm And A Centralised Algorithm, Ciarán O’Loughlin

Dissertations

Particle Swarm optimisation (PSO) is a particular form of swarm intelligence, which itself is an innovative intelligent paradigm for solving optimization problems. PSO is generally used to find a global optimum in a single optimisation function. This typically occurs on one node(machine) but there has been a significant body of research into creating distributed implementations of the PSO algorithm. Such research has often focused on the creation and performance of the distributed implementation in an isolated manner or compared to different distributed algorithms.

This research piece aims to bridge a gap in the existing literature, by testing a distributed implementation …

Feature Highlighting Visualization, Sui Gong

Dissertations

This dissertation presents a collection of visualization techniques that highlight features (i.e, certain visual aspects that are interesting to the viewers, such as sharp corners on a boundary). These include three Marching Squares extensions: (1) Sharp Corner Sensitive Marching Squares (SCS-MS) that recovers sharp corner features in isocontours, (2) Dual Marching Squares (DMS) that recovers curved features in isocontours and (3) Fine Feature Sensitive Marching Squares (FFS-MS) that recovers small and narrow areas enclosed by boundaries. Also included is a novel motion visualization technique that generates speedlines that mimick the speedline style of Manga artist Osamu Tezuka. Experimental results and …

The High Confidence Data Classification Method With Near Zero Classification Error, Truong Xuan Tran

Dissertations

Many machine learning applications require a high degree of confidence in the correctness of the classification results. Ideally, no decision made by the classification model should be a misclassification. However, no classifier can guarantee to provide a correct classification for all data items. Therefore, it is reasonable to allow the classification model to classify a data item only when the certainty level is high and reject to make a decision if the certainty level is not high. In this dissertation, a high confidence data classification method is developed. The method helps the classification model avoid classifying data items that are …

Secure Data Integrity In Wireless Ad Hoc Networks, Elbasher O Esalmi Elmahdi

Dissertations

Wireless ad hoc networks (WANETs) have become increasingly popular in our everyday business and personal lives. As long as nodes in the network belong to the same organization and share the same goal, it can generally be expected that all nodes can be trusted. So, without any security measures in place, any node is capable of compromising the integrity of the data it forwards. It is necessary to save or secure data transmission in WANETs to achieve effective communication because most of the routing protocols proposed for WANETs assume a trusted and reliable environment and they do not consider the …

Hardware Security Primitives Using Nand Flash Memory, Mohammad Sadman Sakib

Dissertations

Counterfeit electronics is a serious problem for ensuring the security and reliability of any electronic system. Unfortunately, the number of counterfeit components has increased considerably after the introduction of horizontal semiconductor supply chain. Various types of counterfeit ICs – recycled, remarked, overproduced, out-of-spec/defective, cloned, forged documentation, and tampered – have made the supply chain vulnerable to various attacks. Recycled and remarked are the most common counterfeit types among all of them; almost 80% of total counterfeiting. This dissertation focus on providing anti-counterfeit solutions for securing the supply chain of NAND flash chips. There are very few existing solutions on detecting …

Effects Of Altering Variable, Basic Residues Of Ribosomal Proteins Ul4 And Ul22 Facing The Ribosomal Exit Tunnel On Growth, Resistance,And Gene Expression In Escherichia Coli: Focus On Ul22 K90d, Elizabeth A. Franklin

Dissertations

Mutational changes in bacterial ribosomes that confer antibiotic resistance decrease cell fitness. Determining the genetic factors that interconnect antibiotic resistance and cell fitness is critical in the fight against bacterial infections. This study describes gene expression and phenotypic changes presented in Escherichia coli cells carrying a uL22 K90D mutant ribosomal protein, which showed growth defects and resistance to macrolide antibiotics. Other uL4 and uL22 mutation, in basic, non-conserved residues, were examined for phenotypic changes, however the uL22 K90D mutation displayed the most consistent phenotypes when compared to the wild type strain, and thus was the focus of this study. Ribosome …

Energetic Neutral Atom Flux From The Inner Heliosheath And Its Connection To Termination Shock Properties, Bishwas L. Shrestha

Dissertations

The energetic neutral atom (ENA) fluxes observed by the Interstellar Boundary Explorer (IBEX) spacecraft show power-law-like spectra in the energy range ~0.5 to 6 keV. However, the temperature of the thermal core solar wind (SW) protons in the inner heliosheath (IHS) measured by Voyager 2 spacecraft is too low to create keV ENAs with Earth-directed trajectories. On the other hand, the temperature of the pickup ions (PUIs) that are reflected and energized in the upstream motional electric field of the heliospheric termination shock (HTS) is too high to create a significant number of ENAs in the IBEX-Hi energy range. Instead, …

An In Depth Analysis Of Ic And Cg Lightning From The Perspective Of Glm, Jacquelyn S. Ringhausen

Dissertations

The Geostationary Lightning Mapper (GLM) detects total lightning continuously from space without distinguishing intra-cloud (IC) from cloud-to-ground (CG) lightning. This research focuses on improving our understanding of the differences between CG and IC lightning as detected by GLM with the potential for classification of these flashes. First, we explore optical differences in flash characteristics for CG and IC lightning by implementing a Random Forests (RF) model to predict flash type, with Earth Networks Total Lightning Network (ENTLN) acting as truth. The results show the most important flash characteristic for distinguishing flash type is the maximum-group-area while other important features include …

Total Ionizing Dose Effects On The State-Of-The-Art Nand Flash Memories With An Emphasis On Dosimeter Design, Preeti Kumari

Dissertations

Radiation effects are an important reliability concern for space and defense electronics, especially for non-volatile memory (NVM). State-of-the-art radiation hard NVMs have very limited capacity (in megabytes range), and high cost, making them impractical for several applications that require larger storage capacities. In this context, NAND flash memory is very attractive due to its high density (>1 tera-bytes/sq. inch) relatively low cost (<$1 per giga byte), light weight and small form factor. Hence this dissertation conducts a systematic study on the radiation effects on the commercially available off-the-shelf NAND flash memory chips. First, an experimental demonstration of radiation effects were performed on the 3-D NAND flash memory using a Co60 Gamma-ray source at Sandia National Laboratory. A significant layer-to-layer bit error variation within a physical memory block of the irradiated memory chip was observed. The possible application of these findings for the radiation-tolerant smart memory controller design were explored. Second, this dissertation evaluates a radiation induced error mitigation strategy using read-retry method. The read-retry function is typically offered in the high-density NAND memory chips to recover data once the default memory read method fails. In this work the read-retry method was applied on the irradiated 3-D NAND chip and an algorithm is proposed for its efficient implementation. Third, a systematic study was conducted on the effects of low dose gamma radiations ( 2rad(Si)/day) on high density NAND flash memory chips. The measured cumulative bit error rate (BER) over two months shows significant linear increase with exposure time and BER is independent of the prior damage. Fourth, a theoretical framework was developed to understand the total ionizing dose sensitivity of the commercial flash memory chips. The theoretical framework motivated the basic design rules for using the commercial flash memory chips as dosimeter.

Charge Structure In Central Argentina Thunderstorms : Characterization And Processes, Bruno Lisboa Medina

Dissertations

In the RELAMPAGO-CACTI field campaigns held in the Argentinian province of Cordoba from November 2018 to April 2019, multiple instrumentations were deployed to study thunderstorms that are among the most intense in the world. In this study, the charge structures within these thunderstorms are investigated, along with the conditions associated with each charge structure archetype such as meteorological conditions, cloud condensation nuclei concentration, and radar-inferred microphysical and kinematic processes. Tested conditions are thought to contribute to high liquid water contents in the mixed-phase layer, which induce positive charging of graupel and anomalous charge structure storms through the non-inductive charging mechanism. …

Event-Driven Servers Using Asynchronous, Non-Blocking Network I/O: Performance Evaluation Of Kqueue And Epoll, Lorcan Leonard

Dissertations

This research project evaluates the performance of kqueue and epoll in the context of event-driven servers. The evaluation is done through benchmarking and tracing which are used to measure throughput and execution time respectively. The experiment is repeated for both a virtualised and native server environment. The results from the experiment are statistically analysed and compared. These results show significant differences between kqueue and epoll, and a profound impact of virtualisation as a variable.

A Program Evaluation Of One School’S Third Through Fifth Grade Instructional Practices, Yvette Edwards

Dissertations

The purpose of this study was to determine whether the instructional practices implemented by teachers using the State Standards were effective for instructing students in Grades 3-5 who were economically disadvantaged. The context of this inquiry was an urban elementary school in a large public school district in the United States of America. The need to implement an effective strategy to improve teacher instructional practices to improve student achievement using the State Standards was an issue in schools of the district under study with students who were economically disadvantaged. The need to meet the rigor necessary for students to obtain …

Finding The Child: Exploration Into Pedagogical Foundations In The Roman Catholic Church, Erica L. Saccucci

Dissertations

Children are important members of society. Their membership as participants in humanity has gotten lost at times throughout history. Children have a particular type of dependency in relationships with the adults around them. This means that adults need to understand children in a different light; from the perspective of the child. In Roman Catholic social ethics, children are always understood as under the authority of their parents. Rarely are children understood in a way that gives them dignity in their subjectivity. This work provides a historical review of the theological ethics of child in the Roman Catholic Church from both …

Characterizing Galectin And Lysosomal Rupture's Role In Spreading Parkinson Disease Pathology, Kevin Burbidge

Dissertations

The misfolding and subsequent accumulation of alpha-synuclein (α-syn) is central to the pathogenesis of Parkinson's disease (PD). Several lines of evidence suggest pathological α-syn spread cell-to-cell via a "prion-like" mechanism. Furthermore, this pathological α-syn is capable of "seeding" further misfolding of non-pathological α-syn, converting them to the pathological form. While a vast body of both genetic and experimental evidence indicates that α-syn is critical to PD development, how α-syn induces progressive neuronal dysfunction and cell death remains unclear.Autophagy, conventional for macroautophagy, is the primary degradation pathway for α-syn aggregates. Autophagy also influences the unconventional secretion of both pathological and non-pathological …

The Development Of The Country Satisfaction Scale, Daewon Kim

Dissertations

In light of nation-wide events and its impact on mental health, this study developed the Country Satisfaction Scale (CSS) to measure individual’s country satisfaction. This study interviewed 7 participants in the United States to generate scale items, collected data for preliminary factor analysis (N = 371), and for final factor analyses (N = 802). The results confirmed a 3-factor (Systemic Structures, Equality & Acceptance, and Resources & Benefits) structure with two additional complementary factor models: second-order 3-factor model and bifactor-(S-1) model with general (G) factor and 2 specific factors. Further validity tests also confirmed the CSS. The results of this …

Political Justificationism: A More Realistic Epistemology Of Political Disagreement, Randolph Jay Carlson

Dissertations

Disagreement is probably the most salient feature of our contemporary political environment. This project aims to examine political disagreements from the perspective of the recent discussions of the epistemology of disagreement more generally. Some, known as conciliationists, argue that when confronted with a disagreement with someone who is equally knowledgeable and well-informed as you are on the issue (known as an "epistemic peer"), one should become substantially less confident in that antecedently held belief. While some have tried to straightforwardly apply the conciliationist approach to political disagreements, I argue that such an approach makes us vulnerable to significant cognitive biases …

Disrupting The School-To-Prison Pipeline: A Mixed-Methods Systematic Review Of Alternative Discipline Practices To Reduce Exclusion And Promote Equity, Cara Diclemente

Dissertations

Zero tolerance policies were designed to create safety by implementing automatic exclusion (e.g., suspensions, expulsions) for misbehavior in response to rising school violence in the United States. However, evidence over the past four decades shows that these policies fail to increase objective and subjective safety, and instead foster poor school climate and disproportionate rates of minority groups in the school-to-prison pipeline. Previous research and literature reviews suggest there are a host of developing Multi-Tiered System of Supports (MTSS) practices that have promising potential to reduce exclusionary outcomes and foster equitable treatment of vulnerable student populations, such as Positive Behavioral Intervention …

Ecological Systems In The Contexts Of Foster Care And Parental Incarceration, Lauren A. Hindt

Dissertations

This bundled dissertation sought to advance research about children in the contexts of foster care and/or parental incarceration. The first study, “Developmental Differences in Children's Visits with Their Parents in Jail,” expanded upon previous research of young children's experiences visiting jail by including a sample of 3-17-year-olds. The study described children's visitation through quantitative (measured by the Jail-Prison Observation Checklist) and qualitative (themes gleaned from observations of children's visits with parents in jail) analyses with an ecological systems framework. The second longitudinal study, “Visits with Fathers Involved in the Criminal Justice System and Behavioral Outcomes among Children in Foster Care,” …

Molecular Determinants Of Fetal Tolerance And The Transition To Adult Immunity, Yi Wei Lim

Dissertations

The perinatal immune system is highly tolerogenic and is phenotypically and functionally distinct from the adult immune system. This tolerogenic nature is a double-edged sword for newborns. While it is beneficial to prevent excessive inflammation against the vast array of foreign antigens encountered after birth, it also causes a lack of immune responses to life-threatening infections. My dissertation research aims to investigate the mechanisms by which perinatal T cells contribute to immune tolerance in infants. A deeper understanding of the nature of the perinatal immune system will provide pivotal knowledge to develop safe and effective strategies to protect infants from …

Social Determinants Of Economic Self-Sufficiency (Ess) In Health Profession Opportunity Grants (Hpog): Focusing On The Process Of Health Care Career Pathways, Jang Ho Park

Dissertations

The purpose of this dissertation was to investigate the social determinants of economic self-sufficiency among low-income jobseekers in a federally sponsored healthcare career pathways program. Particularly this dissertation focused on the effects of the process element of self-sufficiency called psychological self-sufficiency, which consist of perceived employment barriers (PEB) and employment hope (EH) (Hong 2013; 2016). Although many studies have evaluated the effectiveness of workforce development programs that focus on economic outcomes, little empirical research has been conducted to examine the psychological prerequisites for achieving economic self-sufficiency. To address this gap in the literature, this dissertation examined potential effect of psychological …

Unique Approaches To Novel Antifungal Discovery, Chelsea Nichole Powers

Dissertations

No abstract provided.

The Effect Of Microstructural Defect Evolution During Elastic Fatigue Loading On Subsequent Mechanical Properties, Joseph Indeck

Dissertations

Evolution of mechanical properties due to fatigue loading is often overlooked in the design process. Material properties in the as-received condition from a vendor are characterized and then these properties become the basis of design considerations. The effect of expected fatigue loading during operation and its potential to degrade mechanical performance is frequently accounted for with appropriate safety factors. Most notably, the aerospace industry does not have the luxury of large safety factors due to the detrimental effect of weight on cost and performance. Therefore, it becomes necessary to quantify not only the change in mechanical properties as a function …