Digital Commons Network^™

Discovery Of Counter Iads Swarming Autonomy Behaviors With Machine Learning, Joshua Robbins

Dissertations

Counter air-defense operations in highly contested airspaces pose significant risk to human life and scarce material resources, making it desirable to reduce the exposure of personnel to risk of loss of life and limb. Replacing human-piloted air platforms with a swarm of low-cost, unmanned systems in the contest for air superiority is therefore an area of intense interest. However, no doctrinal or tactical best practices for swarming combat yet exist. This dissertation documents research conducted to develop a systematical framework for discovery of counter-air defense tactics for unmanned aerial vehicles under control of a cognitive agent, using a reinforcement learning …

A Pipeline To Study Hst Acs/Wfc3 Data And Examples Of Its Applications, William V. Waldron

Dissertations

Even at over 30 years after its launch, HST still provides cutting-edge data in the optical, especially with its imaging cameras WFC3 and ACS. We present a pipeline to reduce and study the WFC3 and ACS data on nearby galaxies. Particularly, the results on an archetypal galaxy undergoing RPS, ESO 137-001, in the nearby cluster Abell 3627, are discussed in detail. ESO 137-001 is known to host a prominent tail caused by RPS that is detected in many bands from X-rays, Hα to CO. The HST data reveal significant features indicative of RPS such as asymmetric surface brightness and dust …

Development Of An Explainability Scale To Evaluate Explainable Artificial Intelligence (Xai) Methods, Stephen Mccarthy

Dissertations

Explainable Artificial Intelligence (XAI) is an area of research that develops methods and techniques to make the results of artificial intelligence understood by humans. In recent years, there has been an increased demand for XAI methods to be developed due to model architectures getting more complicated and government regulations requiring transparency in machine learning models. With this increased demand has come an increased need for instruments to evaluate XAI methods. However, there are few, if none, valid and reliable instruments that take into account human opinion and cover all aspects of explainability. Therefore, this study developed an objective, human-centred questionnaire …

Evaluation Of Automated Eye Blink Artefact Removal Using Stacked Dense Autoencoder, Matthew Rigney

Dissertations

The presence of artefacts in Electroencephalograph (EEG) signals can have a considerable impact on the information they portray. In this comparative study, the automated removal of eye blink artefacts using the constrained latent representation of a stacked dense autoencoders (SDAE) and comparing its ability to that of the manual independent component analysis (ICA) approach was evaluated. A comparative evaluation of 5 stacked dense autoencoder architectures lead to a chosen architecture for which the ability to automatically detect and remove eye blink artefacts were both statistically and humanistically evaluated. The ability of the stacked dense autoencoder was statistically evaluated with the …

Scrolling Vs Paging: Reading Performance And Preference Of Reading Modes In Long-Form Online News, Richard Herlihy

Dissertations

This study explores the impact of scrolling and dynamic pagination in long-form online documents on reader performance and reader experience. Previous research has produced mixed results, indicating no difference between modes, or a positive effect favouring scrolling. Recent advances in web standards have enabled simpler, dynamic, performant methods of pagination to tailor content responsively to any screen, meriting renewed study in this area. This paper uses one such method to load subsequent online news pages instantly without buffering. In an online browser experiment with 38 participants, an increase in reading speed in the scrolling mode was found at a level …

Schooled To The Streets? Exploring The Relationship Between K-12 Educational Experiences And Early Careers In Activism, David Abraham Castro

Dissertations

Since the late eighteenth century, organizing and activism have been part of the urban landscape, from the labor organizing of Eugene Debs in the early twentieth century to the community organizing work of Saul Alinsky during the 1950s and 1960s. The development of community organizers is strongly tied to local institutions such as factories, houses of worship, and schools. For many youths in Chicago, schools often become the sites of political and social awakening and lead to activism beyond the schoolhouse. Within the current context of urban education scholars, practitioners, policymakers, and community organizers alike agree that the perspectives of …

Investigating The Bactericidal Activity Of Lactobacillus Crispatus Cell-Free-Supernatant, Omar Majed Abdul-Rahim

Dissertations

Antimicrobial-resistant (AMR) microorganisms are an increasingly seriousproblem worldwide, accounting for thousands of fatalities annually. The current literature on combating AMR pathogens often centers on commensal microbes such as Lactobacillus species, which are most frequently found in asymptomatic ‘healthy’ patients and are believed to elicit protective effects. In this dissertation, I sought to investigate the protective effect of Lactobacillus crispatus, utilizing our vast collection of clinical isolates. Previous work from our lab had found that cell-free-supernatant (CFS) of L. crispatus is robustly bactericidal, and that this killing activity does not depend on hydrogen peroxide or lactic acid. We identified phenyl-lactic acid …

Broaching The Topics Of Religion And Spirituality In Therapy: Considering The Influence Of Therapist Competence And Organizational Competence, Papa N. Adams

Dissertations

Many individuals have identified religion and/or spirituality (R/S) as integral in the construction of their worldview and important in mental health. Research has demonstrated that clinicians hold positive attitudes towards integrating R/S into therapy yet reported low levels of actually integrating R/S into therapy sessions. This study examined therapist behavior in regard to broaching discussions about R/S in psychotherapy sessions. This study proposed that clinician broaching behavior would be correlated with the clinician’s R/S competence. Furthermore, the relationship between broaching and clinician’s competence would be moderated by the R/S competence of the clinician’s environment (defined as the organizational/institutional R/S competence). …

School Leaders’ Assessment Of Teachers’ Preparedness For Culturally Responsive Teaching, Victoria Maria Siliunas

Dissertations

Societal and school inequities continue to be highlighted via widening achievement gaps that adversely impact historically marginalized groups of students and their communities. An acknowledgement of the importance of developing teachers who are prepared to work with students of culturally differing identities from their own in the day-to-day work of teaching has inspired a shift in language and practice from a more general multicultural approach to a culturally responsive teaching methodology in which a purposeful inclusion of the ethnic and cultural backgrounds of students is prioritized. Addressing challenges schools face related to cultural difference between teachers and the students they …

Self-Efficacy And Job Satisfaction As Predictors Of Burnout Among School Psychologists In The Midwest United States, Elizabeth Mcknight-Romney

Dissertations

Problem

The concept of burnout is expressed as a syndrome evidenced by chronic exhaustion, depersonalization, and a lack of personal accomplishment. Burnout or work burnout syndrome is conceptualized as a prolonged process of emotional fatigue, involving loss of motivation and expectations, generating a feeling of failure affecting personal, work, and social levels (Maslach et al., 2001). Victims of burnout usually become exhausted, cynical about work-related matters, and question their capacity or ability to perform. Job burnout includes feeling exhausted physically, emotionally, and or mentally in the context of work (Maslach & Jackson, 1981). The demanding profession of school psychology has …

A Study Of Teacher Burnout In Private Seventh-Day Adventist And Public Schools In Trinidad/Tobago And Michigan, Usa, Carla Copeland-Joseph

Dissertations

Problem

Burnout as described by Maslach and Leiter (2007) is a syndrome involving psychological processes that result from Emotional Exhaustion, Depersonalization and diminished Personal Accomplishment in the workplace. It is represented as a stressful experience that is rooted in a person’s own interpretation of social relationships and needs. The aim of this study was to investigate teacher burnout and its interactions with individual factors (Gender, Years of Experience, Emotional Intelligence, Nationality), organizational factors (School Type, School Culture), and transactional factors (Technology Use, Teacher Self-Efficacy) for teachers in Trinidad and Tobago and the state of Michigan in the United States. The …

Racial And Cultural Competence Through The Eyes Of Public-School Educators, Laquita Mcmillion

Dissertations

The discussion of racial and cultural competence in public schools today is necessary. The student population of public schools across the United States has significantly grown racially and culturally diverse. Through the use of a narrative inquiry and a critical lens, this study explored the perception and experiences of public-school educators focused on the topic of racial and cultural competence as it relates to their classroom practice and educational policies. The focus of this research (1) describes and analyzes my personal experiences through the use of qualitative approaches, (2) shares the experiences and perceptions of three public-school educators, and (3) …

"You Must Prophesy Again": The Mission Of God's People In Revelation 10-14, Adenilton Tavares De Aguiar

Dissertations

The primary task of this study was to delineate the theology of mission in the book of Revelation, with a focus on chaps. 10–14 and special attention to the people of God as participants in the mission of God. The historical survey demonstrated that the theology of mission conveyed by the book of Revelation is a topic broadly neglected in recent scholarship and, hence, requires an in-depth treatment. The object of research was addressed from a biblical-theological perspective by means of an exegetical analysis of relevant passages and key terms that were identified on the basis of a semantic field …

Ensemble Approach To The Semantic Segmentation Of Satellite Images, Brendan Kent

Dissertations

Automatic classification and segmentation of land use land cover(LULC) is extremely important for understanding the relationship between humans and nature. Human pressures on the environment have drastically accelerated in the last decades, risking biodiversity and ecosystem services. Remote sensing via satellite imagery is an excellent tool to study LULC. Research has shown that deep learning encoder-decoder architectures have achieved worthy results in the area of LULC, however the application of an ensemble approach has not been well quantified. Studies have shown it to be useful in the area of medical imaging. Ensembling by pooling together predictions to produce better predictions …

An Analysis On Network Flow-Based Iot Botnet Detection Using Weka, Cian Porteous

Dissertations

Botnets pose a significant and growing risk to modern networks. Detection of botnets remains an important area of open research in order to prevent the proliferation of botnets and to mitigate the damage that can be caused by botnets that have already been established. Botnet detection can be broadly categorised into two main categories: signature-based detection and anomaly-based detection. This paper sets out to measure the accuracy, false-positive rate, and false-negative rate of four algorithms that are available in Weka for anomaly-based detection of a dataset of HTTP and IRC botnet data. The algorithms that were selected to detect botnets …

Dark Patterns: Effect On Overall User Experience And Site Revisitation, Deon Soul Calawen

Dissertations

Dark patterns are user interfaces purposefully designed to manipulate users into doing something they might not otherwise do for the benefit of an online service. This study investigates the impact of dark patterns on overall user experience and site revisitation in the context of airline websites. In order to assess potential dark pattern effects, two versions of the same airline website were compared: a dark version containing dark pattern elements and a bright version free of manipulative interfaces. User experience for both websites were assessed quantitatively through a survey containing a User Experience Questionnaire (UEQ) and a System Usability Scale …

Evaluating The Performance Of Vision Transformer Architecture For Deepfake Image Classification, Devesan Govindasamy

Dissertations

Deepfake classification has seen some impressive results lately, with the experimentation of various deep learning methodologies, researchers were able to design some state-of-the art techniques. This study attempts to use an existing technology “Transformers” in the field of Natural Language Processing (NLP) which has been a de-facto standard in text processing for the purposes of Computer Vision. Transformers use a mechanism called “self-attention”, which is different from CNN and LSTM. This study uses a novel technique that considers images as 16x16 words (Dosovitskiy et al., 2021) to train a deep neural network with “self-attention” blocks to detect deepfakes. It creates …

An Investigation Of The Relationship Between Subjective Mental Workload And Objective Indicators Of User Activity, Greg Byrne

Dissertations

Whilst the concept of physical workload is intuitively understood and readily applicable in system design, the same cannot be said of mental workload (MWL), despite its importance in our increasingly technological society. Despite its origin in the mid 20th century, the very concept of ”mental workload” is still a topic of debate in the literature, although it can be loosely defined as “the amount of mental work necessary for a person to complete a task” (Miller, 1956; Longo, 2014). Several methods have been utilized to measure of MWL, including physiological methods such as neuro-imagery, performance-based metrics, and subjective measures via …

Direct And Constructivist Approaches For The Design Of Instruction In Well-Structured Domains: A Comparison Of Efficiency Via Mental Workload And Performance., Giuliano Orru

Dissertations

This doctoral research investigates the efficiency of two instructional designs: a design based on the direct-instruction approach to learning and its extension with a collaborative activity based upon the community of inquiry approach to learning. This is motivated by the educational challenge associated with the improvement of the learning phase. The goal is to investigate the extent to which highly guided communities of inquiry, when added to direct-instruction teaching methods, can actually improve the efficiency of learners. A total of 577 students participated in the experiments across 24 third-level classes that were divided into two groups. A control group of …

Kg-Cnn: Augmenting Convolutional Neural Networks With Knowledge Graphs For Multi-Class Image Classification, Aidan O'Neill

Dissertations

Computer vision is slowly becoming more and more prevalent in daily life. Tesla has recently announced that it plans to scale up the manufacturing of their Robotaxis by 2024, with this increase in self-driving vehicles being just one example, the importance of computer vision is growing year by year. Vision can be easy to take for granted, as most humans grow up using vision as their primary way of absorbing environmental information. The way humans process and classify visual information differs significantly from how current computer vision systems process and organise visual information. The human brain can use its past …

The Impact Of Emotion Focused Features On Svm And Mlr Models For Depression Detection, Alexandria Mulligan

Dissertations

Major depressive disorder (MDD) is a common mental health diagnosis with estimates upwards of 25% of the United States population remain undiagnosed. Psychomotor symptoms of MDD impacts speed of control of the vocal tract, glottal source features and the rhythm of speech. Speech enables people to perceive the emotion of the speaker and MDD decreases the mood magnitudes expressed by an individual. This study asks the questions: “if high level features deigned to combine acoustic features related to emotion detection are added to glottal source features and mean response time in support vector machines and multivariate logistic regression models, would …

Evaluating The Performance Impact Of Fine-Tuning Optimization Strategies On Pre-Trained Distilbert Models Towards Hate Speech Detection In Social Media, Aidan Mcgovern

Dissertations

Hate speech can be defined as forms of expression that incite hatred or encourage violence towards a person or group based on race, religion, gender, or sexual orientation. Hate speech has gravitated towards social media as its primary platform, and its propagation represents profound risks to both the mental well-being and physical safety of targeted groups. Countermeasures to moderate hate speech face challenges due to the volumes of data generated in social media, leading companies, and the research community to evaluate methods to automate its detection. The emergence of BERT and other pre-trained transformer-based models for transfer learning in the …

Performance Evaluation Of An Edge Computing Implementation Of Hyperledger Sawtooth For Iot Data Security, Sean Connolly

Dissertations

Blockchain offers a potential solution to some of the security challenges faced by the internet-of-things (IoT) by using its practically immutable ledger to store data transactions. However, past applications of blockchain in IoT encountered limitations in the rate at which transactions were committed to the chain as new blocks. These limitations were often the result of the time-consuming and computationally expensive consensus mechanisms found in public blockchains. Hyperledger Sawtooth is an open-source private blockchain platform that offers an efficient proof-of-elapsed-time (PoET) consensus mechanism. Sawtooth has performed well in benchmarks against other blockchains. However, a performance evaluation for a practical application …

Examining The Effects Of Disabilities On Vr Usage And Accessibility Issues For Persons With Disabilities, Sean Williams

Dissertations

Virtual Reality (VR) is an emerging technology that’s popularity has been increasing at a yearly rate. Despite this, concerns about the accessibility of VR devices are ever-growing as many users struggle to use the technology, especially users with disabilities. This study analyses how different types of disabilities affect how often a user uses VR and any associated re-occurring difficulties that are related to specific types of disability. To do this, a previous survey regarding VR accessibility run by Disability Visibility Project and ILMxLAB is examined. In this survey, 79 participants who identify as having a disability answered questions related to …

Phase Rule And Isomorphism Principle Analysis Of Critical Phenomena In Multicomponent Systems, Xingjian Wang

Dissertations

This dissertation investigates critical phenomena in the liquid mixture near its liquid-liquid critical solution temperature, especially for critical effects on solubilities and turbidities. According to the Griffiths-Wheeler rule, the critical effect is expected for the derivatives of a density variable with respect to a field variable in the system with less than two fixed density variables. The power of the phase rule for solving the number of fixed densities and predicting critical effects is examined in multicomponent systems with the numbers of fixed density variables between zero to two. When the excess solid solute is added into a binary liquid …

Investigating The Effect Of An Immersive Extracurricular Stem Program On Underrepresented And Disadvantaged High School Students' Self-Efficacy, Science Anxiety, And Career Aspirations, Nikki Mertz

Dissertations

This mixed methods study was designed to assess how an immersive extracurricular STEM program affected a student’s self-efficacy, science anxiety, and career aspirations. This study utilized the SIC-STEM survey to quantify student self-efficacy in science and the STEM Semantics survey to quantify student interest in STEM. Both surveys also assessed student interest in pursuing careers in STEM. The Science Anxiety survey was used to evaluate how student anxiety in science changed throughout the study. A subject matter survey was utilized to quantify student understanding and comprehension of an advanced science topic. Focus groups were used as the qualitative piece to …

Exploring The Utility Of Geostationary Satellite Observations In Air Quality Studies, Peiyang Cheng

Dissertations

The air quality community uses numerical models for air quality forecasting and establishing regulatory policies. However, the prediction of clouds and the estimation of emissions remain highly uncertain, limiting the credibility and usefulness of model results. This study explored how Geostationary Operational Environmental Satellite (GOES) observations can be used to reduce the uncertainty in air quality simulations. The major findings are summarized as follows. First, assimilating the GOES-13 cloud products into a numerical weather prediction model improved the agreement between model-predicted and satellite-observed clouds by 3.5%. Model surface insolation bias and error were reduced by 7.1 W m^–2 (13.1%) …

Adaptive Sliding Mode Control Of Small Satellites In Formation For Distributed Beamforming Applications, Mason Earl Nixon

Dissertations

The rising popularity of small satellites over the past few decades has created a new boom in space, and, in particular, in low-Earth orbit. Exciting novel applications are being proposed that enable these small satellites to offer many advantages over their monolithic counterparts which can allow for augmentation, or possibly even replacement of more expensive and large alternatives. One particular enabling method is flying small satellites in formation for antenna array applications, which, through coupled dynamical modeling, can be facilitated through robust, nonlinear techniques of control. Thus, control of a perturbed satellite formation antenna array, with dual quaternion dynamics, is …

Nanomaterials In Theranostics : Therapeutics And Diagnosis Against Infectious Diseases, Unnatiben S. Patel

Dissertations

Nanomaterials-based hybrid nano therapy is gaining attraction as a promising way to treat intracellular bacterial infections. Gold-based nanomaterials have been widely used for biomedical applications such as photothermal therapy (PTT). This thesis discusses the development of a combination therapeutic approach that kills intracellular bacteria in conjunction with photothermal and antibiotic therapy using gold nanorod (GNR) based nano-assembly. This NIR laser-activated nano-assembly delivers antibiotics to the site of infection and offers PTT. The synergistic application of both therapies increases the efficacy of treatment. The protected delivery of antibiotics and their release in the proximity of the bacterial surface decreases off-target toxicity …

Accuracy Improvement Of Dynamic Sensors Measured Input Reconstruction Using Sliding Mode Observers, Rajesh Rayala Jayasheelareddy

Dissertations

Sensor dynamics adversely affect the accuracy of the obtained measurement by dynamically distorting the true value. The accuracy of the measurement may be further degraded by noise/exogenous perturbations. A sensor’s accuracy and performance are improved by reconstructing the true input signal of the sensor from the distorted measurement polluted by a corruption signal or exogenous inputs using Sliding mode and Higher-order sliding mode observer (SMO/HOSMO). The proposed technique is used to reconstruct/estimate a sensor’s true signal, thereby improving the transient response and driving the estimation steady state error to zero in finite time. The proposed SMO algorithm is based on …