Digital Commons Network^™

A Deep Learning Framework For Blockage Mitigation In Mmwave Wireless, Ahmed Hazaa Almutairi

Dissertations and Theses

Millimeter-Wave (mmWave) communication is a key technology to enable next generation wireless systems. However, mmWave systems are highly susceptible to blockages, which can lead to a substantial decrease in signal strength at the receiver. Identifying blockages and mitigating them is thus a key challenge to achieve next generation wireless technology goals, such as enhanced mobile broadband (eMBB) and Ultra-Reliable and Low-Latency Communication (URLLC). This thesis proposes several deep learning (DL) frameworks for mmWave wireless blockage detection, mitigation, and duration prediction. First, we propose a DL framework to address the problem of identifying whether the mmWave wireless channel between two devices …

Living On The Outskirts Of Things: Women And Nonbinary People Of Color With Cognitive Disabilities Describe Their Employment Experiences, Laura Spura Rodriguez

Dissertations and Theses

This study examines the experiences of discrimination and the strategies used to navigate employment for women of color and nonbinary people of color (POC) with cognitive disabilities (CD) through their own narratives. Using Dis/ability Critical Race Theory and an interpretive description methodology, this study engaged 10 women of color and/or nonbinary POC with CD in semi-structured interviews in order to answer the following research questions: 1) What stories do women of color and nonbinary POC with CD tell about their experiences seeking employment? 2) What are the narratives of women and nonbinary POC with CD about their experiences of racism, …

The Women Of The Oregon State Insane Asylum: 1900-1910, Rebekah Catherine Averette

Dissertations and Theses

This thesis explores the lives of female patients at the Oregon State Insane Asylum between 1900 and 1910 and examines the significance of that decade as a period of transition in asylum care from a moral treatment model to a focus on moral hygiene practices to subvert insanity before it took root and medicalized psychiatric treatment for severe or chronic cases requiring institutionalization.

At the turn of the twentieth century, state insane asylums were in the aspirational early stages of transforming into specialized psychiatric and medical hospitals. Ultimately, the hoped-for transformation would not materialize in a meaningful way until well …

Residential Ders In Service-Oriented Load Participation: Enhancing Grid Flexibility, Zhongkai Zeng

Dissertations and Theses

Amidst concerns about power consumption during peak periods and potential grid instability, the role of Distributed Energy Resource (DER) aggregation comes into consideration. Smart electric water heaters with remote capabilities and energy storage offer load reduction capabilities that can help maintain grid stability and manage residential energy consumption. DERs address challenges posed by stochastic renewable energy generation and fossil fuel power plant emissions, playing a contributing role in load shifting and enhancing grid flexibility by participating in energy management programs.

However, high unenrollment rates in demand response programs, notably programs that use direct load control, persist due to customer dissatisfaction. …

H1-Conforming Finite Elements On Nonstandard Meshes, Samuel Edward Reynolds

Dissertations and Theses

We present a finite element method for linear elliptic partial differential equations on bounded planar domains that are meshed with cells that are permitted to be curvilinear and multiply connected. We employ Poisson spaces, as used in virtual element methods, consisting of globally continuous functions that locally satisfy a Poisson problem with polynomial data. This dissertation presents four peer-reviewed articles concerning both the theory and computation of using such spaces in the context of finite elements. In the first paper, we propose a Dirichlet-to-Neumann map for harmonic functions by way of computing the trace of a harmonic conjugate by numerically …

Immigration Policy Evaluation For Technology Professionals Immigrants In The United States, Angel Contreras Cruz

Dissertations and Theses

The U.S. Immigration System is complex for technology professionals seeking to relocate to the United States for employment or education. The United States relies on its employment-based immigration to attract and select the best talent to fill the shortage of skilled jobs. Technology professionals, a stream of highly skilled immigrants, tend to contribute and be more beneficial to the U.S. economy, which is one of the principles of U.S. immigration policies. Although U.S. immigration policies are constantly updating, policymakers, experts, and scholars suggest that the United States needs significant immigration reform to solve current issues, such as improving technological capabilities …

Exploring The Curriculum And Institutional Contexts Of Stem Future Faculty Programs, Amy Mae Forester

Dissertations and Theses

While there are a multitude of contributing factors, under-represented student success in STEM appears to be critically interdependent with teaching and learning practices that are responsive to diverse epistemologies and inclusive pedagogies. However, the professional literature has yet to identify a set of faculty development best practices that might guide the field. Furthermore, the institutional supports required to drive the success of STEM-oriented future faculty programs remain unknown. This inquiry proposal intended to address these concerns through a critical comparative qualitative study in seeking evidence-based practices and institutional elements of STEM faculty professional development programs that support diverse graduate and …

Is This My Place? Contributing Factors To Community College Students' Longitudinal Sense Of Belonging And The Connection Of Sense Of Belonging To Student Success, Kelly Elizabeth Love

Dissertations and Theses

Community colleges serve a large percentage of historically under-represented populations including students of color, low-income, and first-generation students. Unfortunately, less than half of students who begin at a community college return the following Fall and only about one-fourth of students eventually graduate. Previous research indicates that students' sense of belonging may be a key factor in retention and completion rates. However, large-scale datasets have yet to comprehensively explore students' sense of belonging in the community college setting. To address that issue, the purpose of this quantitative exploratory study was to examine individual and institutional variables associated with a measure of …

Permission To Play: A District's Initiative To Innovate Kindergarten And Promote Developmentally Appropriate Practices, Cristin Mcdonough

Dissertations and Theses

Kindergarten's original purpose was to promote socialization skills for young children using play. However, recent research has shown an increased focus on teaching literacy and math skills, combined with pronounced increases in more advanced academic tasks and activities. Given this shift in kindergarten, as well as a lack of professional development for teachers to assist them in promoting developmentally appropriate practices, the Kindergarten Innovation Cohort was created in the Portland School District to address these needs for both students and teachers. Using findings from interviews and field notes, the current study addresses the question: What does the implementation of the …

A Hierarchical Decision Model For Evaluating The Strategy Readiness Of Quantitative Machine Learning/Data Science-Driven Investment Strategies, Mohammadsaleh Saadatmand

Dissertations and Theses

Big data and computational technologies are increasingly important worldwide in asset and investment management. Many investment management firms are adopting these data science methods and technologies to improve performance across all investment processes. Researchers actively use these methods to develop more effective systematic investment strategies and produce more reliable outcomes less vulnerable to human decision-making biases. However, the success of such a strategy depends heavily on the scientific rigor applied throughout the process. "Best practices involve understanding how to make better decisions in the research design process. A good question is whether we can make better decisions in developing quantitative …

Designing For Deployable, Secure, And Generic Machine Learning Systems, Li-Yun Wang

Dissertations and Theses

Machine learning systems have catalyzed numerous image-centric applications owing to the significant achievements of machine learning algorithms and models. While these systems have showcased the efficacy of machine learning models, certain challenges persist, such as machine learning system design and security vulnerabilities inherent in deep neural networks. Moreover, the deployment of deep neural network models remains a significant hurdle. This dissertation introduces a multimedia prototyping framework tailored for visual analytical applications, improving the reusability of video analysis software tools with minimal performance overhead. Furthermore, we present novel image-processing techniques designed to bolster the robustness of deep neural networks and propose …

Quantum Search Algorithms For Constraint Satisfaction And Optimization Problems Using Grover's Search And Quantum Walk Algorithms With Advanced Oracle Design, Abdirahman Sheikh Hassan Alasow

Dissertations and Theses

The field of quantum computing has emerged as a powerful tool for solving and optimizing combinatorial optimization problems. To solve many real-world problems with many variables and possible solutions for constraint satisfaction and optimization problems, the required number of qubits of scalable hardware for quantum computing is the bottleneck in the current generation of quantum computers. In this dissertation, we will demonstrate advanced, scalable building blocks for the quantum search algorithms that have been implemented in Grover's search algorithm and the quantum walk algorithm. The scalable building blocks are used to reduce the required number of qubits in the design. …

Adaptive Sampling For Seabed Identification From Ambient Acoustic Noise, Matthew Sullivan

Dissertations and Theses

This thesis discusses distinguishing geoacoustic properties of seabeds by adaptively sampling ambient acoustic measurements using an autonomous underwater vehicle. Modern advancements in seabed characterization motivate an online method for distinguishing between two seabed types using Fourier transformed ambient acoustic noise snapshots. These snapshots are assumed to be associated with their spatial location and seabed, making the goal to organize unlabeled seabed locations. The snapshots are transformed to obtain pairwise similarities between locations. Locations with similarities exceeding a threshold are classified together with the goal of identifying all locations with similarities below this threshold using a process known as level set …

Co-Designing With First-Generation Transfer Students, Randi Petrauskas Harris

Dissertations and Theses

Roughly 80% of community college students indicate that they intend to transfer to a four-year institution, 30% of those students eventually transfer, and 13% of those students persist to graduate with a baccalaureate degree. There has been previous research on transfer students and on first generation students, but the intersection of first-generation transfer students is under-reported. Prior research indicates that sense of belonging is an important factor in student persistence to graduation for transfer students. Higher education institutions, specifically four-year public institutions, are positioned to support first-generation transfer student sense of belonging by fostering a "transfer receptive culture." Recognizing that …

Doubly Almost Bipartite Leonard Pairs, Shuichi Masuda

Dissertations and Theses

In Linear algebra, the concept of Leonard pair (LP) was motivated by the theory of Q-polynomial distance-regular graphs. In this dissertation, we will first give a brief introduction to LPs and to two closely-related classes of objects: (i) bipartite Leonard pairs (BLPs) and (ii) almost bipartite Leonard pairs (ABLPs). Taking these as departure points, we will introduce a new class of object - doubly almost bipartite Leonard pairs (DABLPs). The primary aim of our work is to fully classify (up to isomorphism) this new family. In addition, since there is known to be a natural correspondence between Leonard pairs …

Varecia Rubra (Red Ruffed Lemur) Diel Activity And Calling At Andranobe, Masoala National Park, Madagascar, Hannah Elena Hilden-Reid

Dissertations and Theses

With respect to the natural variation in abiotic and biotic conditions present between daytime and nighttime periods, many animal species show evolutionary adaptations specialized for diurnality, nocturnality, or crepuscularity. Biologists have traditionally viewed categorizations of this kind as fixed within taxonomic groups, emphasizing how intricately species’ survival is contingent on the ability to adapt to low light, high light, or twilight conditions. However, movement away from such distinct temporal niche categories began within chronobiological studies following the discovery of more flexible patterns of activity in numerous taxa during the late 1970s. This shift generated increased interest in elucidating the complex …

Understanding Waveguides In Resonance, Pieter Johannes Daniel Vandenberge

Dissertations and Theses

Several important classes of modern optical waveguides, including anti-resonant reflecting and photonic bandgap fibers, make use of geometries that guide energy in low refractive index material, a property that makes them of significant interest in numerous applications, notably including high-power delivery and guidance. These waveguides frequently exhibit resonance phenomena, in which their ability to propagate an input signal is sharply curtailed at particular operating frequencies. In this work we detail new advances in understanding these resonance effects and their implications for numerical modeling of these structures.

Part 1 focuses on the fields of slab waveguides, relatively simple structures for which …

The Wage Of Wellness: The Relationship Between Socioeconomic Status, Race, And Work Recovery, Emily Julia Ready

Dissertations and Theses

A substantial share of the workforce is made up of low-income workers. Many of these workers fall below the federal poverty line and are considered low socioeconomic status (SES) and are disproportionately more likely to be racial minorities. However, this population is often neglected in the industrial-organizational psychological literature. Specifically, work recovery research has not considered the unique life circumstances of this particular group in the development of the research questions, theoretical framework, or practical implications in relation to this phenomenon. The purpose of the current study is to understand the relationship between socioeconomic status, race, and work recovery experiences …

Numerical Study Of Cone Penetration In Calcareous Sands: Investigating Cone Tip Resistance Correction Factors For Crushable Soils, Stephanie Michelle Hyder

Dissertations and Theses

The cone penetration test (CPT) is used to characterize the behavior and properties of soils, including the susceptibility to earthquake liquefaction triggering. The cone tip resistance relates to liquefaction susceptibility through relative density, where relative density is closely related to both cone tip resistance and liquefaction susceptibility. Currently, published methods of estimating liquefaction potential (i.e., cyclic resistance ratio) are based on silica sands and do not properly characterize calcareous sands. The measured cone tip resistance in calcareous sands is lower than in silica sands at the same relative density; this difference is generally attributed to the higher compressibility of calcareous …

The Relationship Between Adverse Childhood Experiences And Juvenile Offender Typology, Aliza Beth Lipman

Dissertations and Theses

Approximately 1 in 5 girls and in 20 boys in the United States are victims of child sexual assault every year. Child sexual assault can lead to multiple negative short term and long-term impacts affecting general health, mental health, interpersonal relationships, socio-economic status, criminal behavior and more. Prevention research focuses on a thorough understanding of the perpetrators of assault and the context surrounding offenses in order to reduce and prevent assault. Within this research, juvenile offenders are perceived as a single homogenous group whereas adult offenders are consistently specified based on offender and offense characteristics. The exploration of the relationship …

Corporatizing Violence: Targeted Repression Of Indigenous Dissent In Democratic States, Laikaika Layne Rivera

Dissertations and Theses

This thesis explores state repression of disruptive protests against private development projects in democracies. Using a mixed methods approach, including logistic regression and case studies, the research identifies key factors influencing repression. Indigenous leadership, fragmented public opposition, and private elite influence increase the likelihood of violent repression. The findings suggest that when public resistance is insufficient against powerful private interests, coercive institutions resort to violent strategies to quell disruptions and signal increased costs for future dissent. State repression is more likely when the protest movement is comprised of Indigenous groups than compared to those of the general public. The study …

Comparison Of Conventional And Adaptive Acoustic Beamforming Algorithms Using A Tetrahedral Microphone Array In Noisy Environments, Megan Brittany Ewers

Dissertations and Theses

In situ acoustic measurements are often plagued by interfering sound sources that occur within the measurement environment. Both adaptive and conventional beamforming algorithms, when applied to the outputs of a microphone array arranged in a tetrahedral geometry, are able to capture sound sources in desired directions and reject sound from unwanted directions. Adaptive algorithms may be able to measure a desired sound source with greater spatial precision, but require more calculations and, therefore, computational power. A conventional frequency-domain phase-shift algorithm and a modified adaptive frequency-domain Minimum Variance Distortionless Response (MVDR) algorithm were applied to simulated and recorded signals from a …

Faculty Mentors' Influence On Latino/A/X Stem Undergraduates' Stem Identity Development, Sandy Cerda-Lezama

Dissertations and Theses

Despite Latino/a/x college student attendance rising substantially over the past decades, their graduation rates do not match the increased admission rates. In addition, Latino/a/x students are considerably under-represented in STEM. However, research suggests that when these students are encouraged by social partners to have meaningful participation and given resources such as mentoring, this eases the barriers they experience. The current study utilized interviews with 11 Latino/a/x STEM undergraduates (aged 18-29) to understand how faculty mentors influence their STEM identity development. Students shared answers about how faculty promoted and inhibited their STEM identity development through conversations about their sense of competence, …

A Survey Of North American Electric Bicycle Owners, Cameron Steven Bennett

Dissertations and Theses

Rapid recent growth in the popularity of electric bicycles (e-bikes) has captured the attention of transportation researchers and policymakers seeking safe, sustainable, and active alternatives to conventional transportation modes. This thesis presents an investigation of e-bike owners in North America, complementing previous efforts in 2013 and 2017, and suggests implications for North American transportation planning.

An online survey was distributed to e-bike owners in the United States and Canada through email outreach, purchase incentive programs, and social media. The survey included questions on the respondents’ demographics, e-bikes, purchase decisions, travel behavior, perceptions of e-bikes, crash experience, maintenance needs, and receipt …

Teaching In A Kenyan Refugee Camp: A Critical Ethnography Of The Impact Of Teacher Preparation And Cultural Experience On Pedagogy, James Adiok Mayik

Dissertations and Theses

This research involved an investigation of the classroom experiences of formally unprepared refugee teachers in Kakuma Refugee camp. The purpose was to understand how refugee teachers with no preservice preparation in accordance with the standards of Kenya Teacher Service Commission (TSC) perceive and interact with pedagogical content knowledge (PCK) and cultural relevancy in their daily classroom experiences with students in a refugee camp-based school in Kenya. What informed this study was the view that refugee teachers bring with them their respective and diverse cultural knowledge--ontology, epistemology, and axiology. To gain better understanding of the experiences and perspectives of these educators, …

Understanding The Other: Mentor Ethnocultural Empathy And Relationship Quality And Duration In Youth Mentoring, Miriam Miranda-Diaz

Dissertations and Theses

Given the positive youth outcomes associated with participation in mentoring programs, there is growing interest to explore factors associated with mentoring relationship quality and duration in formal youth mentoring programs. In comparison to the majority of volunteer mentors, many young people participating in formal mentoring programs are of a racial-ethnic minority group and tend to be economically disadvantaged. This study investigates factors associated with these socio-cultural background differences between mentors and mentees. More specifically, this study investigates the association between a mentor's level of ethnocultural empathy, as reflected in empathic perspective-taking and acceptance of cultural differences, and the quality and …

Queer Rural Youth Online: A Digital Ethnography, Joseph Robert Burns

Dissertations and Theses

This thesis is based on digital ethnographic fieldwork conducted in 2023 within Queer subcommunities on the social media sites Reddit and Twitter (now known as X) and data collected from interviews with Queer rural youth members of these communities. The data reveal that social media use directly influences the lives and actions of Queer rural youth, who use the space to build social connections, shape their personal identities, and seek advice pertaining to their in-person lives and decisions. By using these spaces, Queer rural youth build both bonding and bridging social capital, learn to subvert restrictions to their Internet access, …

It Takes A Village: An Examination Of Social Relationships And Mental Health, Em Francis Trubits

Dissertations and Theses

Social relationships are impactful to mental health and well-being, both positively and negatively. Different sources of support vary in their ability to meet our needs and ultimately influence our well-being. While research has examined aspects of supportive and harmful social relationships and mental health, much of this work is cross-sectional or limited to a single source of support. This dissertation aimed to better elucidate the relationship between social relationships and mental health by integrating multiple theoretical perspectives and multiple sources of support, in a series of three empirical studies in order to inform theory and interventions targeting mental health of …

A Qualitative Study On The Persistence Of Seasoned Student Affairs Professionals, Russell Taylor Jones

Dissertations and Theses

The attrition of student affairs professionals has plagued higher education for decades and continues to negatively impact the profession. Over 40% of new student affairs professionals leave the field and leading contributors to this departure include unsustainable working norms, outdated and deficient job-related incentives, and burnout. Prior research focused primarily on why staff intend to leave and do leave student affairs, but little research has explored why professionals persist and successfully cultivate a long-term, sustainable career in student affairs. The purpose of this study was to explore the experiences of seasoned student affairs professionals who have persisted in the field …

The Mirror Project: Reflections On The Experiences Of African-American Female Adolescents Experiencing Foster Care, Bahia Anise-Cross Degruy Overton

Dissertations and Theses

As the author Zora Neale Hurston says, "If you're silent about your pain, they'll kill you and say you enjoyed it." The Mirror Project (MP) aims to break this silence by giving voice to Black women who have experienced foster care in Portland, Oregon during their adolescence. In focus groups and interviews, participants shared their stories. Racial identity development theory, phenomenology and Afrocentric feminist epistemology provided lenses for gaining insight into their experiences in a predominantly white city. The MP revealed six themes: lack of youth engagement in foster care decisions, the need for a cultural lens in social work, …