Digital Commons Network^™

An Integrated Framework For Early Detection And Transmissibility Assessment Of Emerging Variants In Wastewater, Xingwen Chen, Tin Phan, Wei Lin Lee, Katie Clark, Steven F Rhode, Samantha Brozak, Bruce Pell, Tsultrim Palden, Mats Leifels, Anna Gitter, Yang Kuang, Stefan Wuertz, Janelle Thompson, Kristina D Mena, Eric J Alm, Fuqing Wu

Faculty, Staff and Student Publications

Tracking the emergence of new viral variants is critical for epidemic preparedness, but remains challenging because variants typically circulate at low prevalence during the early phase of outbreaks. Here, we present an integrated framework that combines sensitive variant detection in wastewater with quantitative assessment of transmissibility through dynamic epidemic modeling. Using the SARS-CoV-2 Omicron variant as a proof of concept, we developed a novel nested allele-specific RT-qPCR assay (NAS-PCR) that achieved a thousand-fold increase in sensitivity compared with allele-specific RT-qPCR (limit of detection: 0.5 copies/μl). NAS-PCR detected Omicron in wastewater samples from the Greater Boston area starting in September 2021, …

Securing Cloud-Native Systems: From Vulnerability Analysis To External And Insider Threat Detection, Jiongchi Yu

Dissertations and Theses Collection (Open Access)

Cloud-native systems have become the backbone of modern software infrastructure. However, their dynamic resource orchestration and complex configurability introduce a large attack surface and intricate security challenges. Adversaries can externally exploit vulnerabilities in cloud components or perform insider movement within cloud environments to launch attacks. As these systems increasingly support critical services, security breaches can lead to severe operational and economic consequences.

Despite extensive efforts in vulnerability detection and attack monitoring, existing approaches struggle to remain effective in cloud-native environments characterized by rapid evolution and inherent heterogeneity. In particular, they exhibit three fundamental limitations: (1) Insufficient understanding of defect patterns …

Enhancing Reliable Performance Of Microgrids With Autonomous Control Of Distributed Energy Resources, Sahand Liasi

All Dissertations

This dissertation presents a comprehensive investigation into enhancing the reliability, efficiency, and autonomous operation of modern power networks through advanced microgrid integration and control strategies. The research addresses critical challenges across three interconnected domains: microgrid control, thermodynamic modeling of heat recovery system (HRS), and optimal distribution network reliability.

In the realm of microgrid control, this work introduces novel methodologies for grid forming inverter-based resources (IBRs). A significant contribution is the development and validation of an "Auto Frequency Change" controller, which drastically reduces microgrid synchronization time with the main grid from several minutes to approximately four seconds, with theoretical potential for …

Generative Ai Of Breast Cancer Progression In Gene Expression Space, Xusheng Ai

All Dissertations

Breast cancer is one of the most common and deadly cancers in the world. Although doctors can use gene activity data to better understand different types of breast cancer, it is still difficult to identify the most important genes and to track how the disease changes over time. This is partly because gene data are very large and complex.

This dissertation develops a computer-based framework to study breast cancer using gene expression data. The work focuses on three goals: creating realistic synthetic gene data, identifying important genes linked to cancer, and modeling how breast cancer changes from normal tissue to …

Safe Control Design For Quadruped Locomotion In Unstructured Environments Using Linear Transfer Operators, Sriram Sundar Krishnamoorthy Shankara Narayanan

All Dissertations

Deploying quadruped robots in unstructured, obstacle-rich environments requires control and planning methods that remain safe and reliable despite complex terrain geometry, limited sensing, and inevitable modeling errors. This thesis develops operator-theoretic tools for safe control design of robotic systems using linear transfer operators, with a focus on quadruped locomotion in unstructured environments. The central goal is to develop a unified operator-theoretic framework for safe control design based on the Perron–Frobenius (P–F) and Koopman operators. In particular, the thesis leverages \emph{density functions} to develop safe navigation frameworks in the dual space of densities. In the operator-theoretic perspective, the P–F operator governs …

Monomial Quadratic Identities Of Hecke Eigenforms, Trevor Vilardi

All Dissertations

Duke and Ghate independently studied the question of when it is possible for the product of two eigenforms to be an eigenform. In this dissertation, we take up a generalization of that question, namely is it possible for the product of two eigenforms to be equal to a different product of two eigenforms? Under this formulation, the question becomes closer to one about unique factorization, i.e., how closely do eigenforms work like irreducible elements? Our conjecture is that there are only finitely many cases where the product of two eigenforms is equal to a different product of two eigenforms, and …

The Impact Of Label Material On Perceived Value And Environmental-Friendliness Of Beverages In Returnable Glass Bottles Versus Actual Environmental Impact Via Life Cycle Assessment, Toni Sharp

All Dissertations

With guidance from the EPA to reduce virgin packaging use and alternatively increase reuse, the concept of reusable packaging has re-emerged as a potential sustainable alternative to single-use and recyclable packaging. For businesses, an understanding of the potential environmental benefits of switching from single-use packaging to reusable packaging, along with consumer willingness to pay for sustainable packaging are paramount. Existing literature on willingness to pay (WTP) for ethical or sustainable products typically relies on consumers’ stated preferences found through surveys using hypothetical products and prices. It has been revealed that sustainability claims printed on the label or products in glass …

How Academic Pressure Is Declining The Mental Health Of South Korean Students, Lilyanne Boyland

East Asian Studies

South Korea’s education system is widely recognized for its academic excellence; however, this may highly impact students’ mental health and overall well-being, which can hinder their academic performance. Students are known to dedicate long hours of their day to their education, in addition to their daily academic schedules. This study focuses on how academic pressure, that is mostly driven by parents and educators, as well as traditional cultural values on education, affects the mental health of South Korean students. This thesis is divided into three sections: Historical and Cultural Contexts, South Korea’s Current Educational Environment, and Next Steps for South …

Intersectionality And Belonging: Higher Education Mathematics, Ashley Natalie

Mathematics and Statistics

Students with intersecting marginalized identities (such as race, gender, socioeconomic status, disability, or first-generation background) often face unique challenges in advanced mathematics that affect confidence, participation, amounting to a sense of belonging. These experiences remain underrepresented in mathematics education research. This qualitative, narrative-based study examines how these students experience classroom dynamics and belonging in upper-level mathematics courses. Semi-structured interviews will be analyzed thematically to identify patterns related to identity, classroom culture, instructor behavior, and peer interactions. Findings aim to highlight barriers and supportive practices, informing more inclusive teaching strategies and equitable learning environments in advanced mathematics.

Intersectionality And Belonging: Higher Education Mathematics, Ashley Williams

Mathematics and Statistics

Students with intersecting marginalized identities (such as race, gender, socioeconomic status, disability, or first-generation background) often face unique challenges in advanced mathematics that affect confidence, participation, amounting to a sense of belonging. These experiences remain underrepresented in mathematics education research. This qualitative, narrative-based study examines how these students experience classroom dynamics and belonging in upper-level mathematics courses. Semi-structured interviews will be analyzed thematically to identify patterns related to identity, classroom culture, instructor behavior, and peer interactions. Findings aim to highlight barriers and supportive practices, informing more inclusive teaching strategies and equitable learning environments in advanced mathematics.

Mechanism Of Formation Of Guanine-Guanine Crosslinks As Products Of One-Electron Oxidation Of 1-Methylguanosine In Acidic Medium, Ibrahim Braimah Mr

Electronic Theses and Dissertations

Reactive oxygen species (ROS) from normal metabolism and environmental exposure may cause oxidative DNA damage. Guanine (G) is the most oxidizable nucleobase. One-electron oxidation (OEO) of G in produces guanine radical cation (G•⁺), which deprotonates to form guanyl radical G(-H)•.This radical exists in two tautomeric forms: G(N1-H)• and G(N2-H)•. Dimerization of guanyl radical yields G-G cross-links (D1/D2); a tautomeric form for dimer formation remains elusive. This study presents the first characterization of G• dimerization products from the OEO of 1-MeGuo in acidic medium. Photolysis at 470 nm in the presence of S₂O₈²⁻ and Ru(II)(bpy)₃²⁺ generates two major stereoisomers (D1AW* and …

Academic And Demographic Predictors Of Retention And Persistence In Business Programs: Post-Covid Cohorts Of Traditional And Ncccs Transfer Students, Matthew K. Crump

Electronic Theses and Dissertations

This quantitative study examined academic and demographic predictors of first-year retention and major persistence among traditional first-year and North Carolina community college transfer students enrolled in undergraduate business programs. Guided by Tinto’s 1993 Model of Student Retention and Astin’s 1984 Theory of Student Involvement, the research focused on students who entered two AACSB-accredited institutions within the UNC System during Fall 2021, Fall 2022, and Fall 2023 as traditional first-year students or as transfer students from North Carolina community colleges.

Institutional data from the Banner Student Information System provided the basis for logistic regression analyses that examined predictors including high school …

Durable, Distributed Llm Inference On Cots Devices, Brycen E. Dunn

Electronic Theses and Dissertations

The advancement of Large Language Models (LLMs) has fundamentally changed the nature of natural language processing. The substantial memory requirements of frontier models creates a significant barrier to entry, centralizing inference. This thesis presents the design and implementation of a distributed inference framework designed to democratize LLMs by leveraging commodity devices. The framework combines the resources of heterogeneous COTS devices into a unified compute pool, enabling the inference of models exceeding a single device's memory capacity. A novel Task Partitioning Engine (TPE) analyzes model architectures, profiles node capabilities, and supports pipeline and expert parallelism strategies. The primary contribution is a …

A Machine Learning Framework For Early-Stage Cost Estimation Of Transportation Projects, Pritom Paul

Electronic Theses and Dissertations

To address the limitations of traditional planning-level cost estimating methods, such as reliance on statewide averages, heavy reliance on engineering judgment, and high levels of inaccuracy, this study developed two data-driven frameworks and corresponding tools. The first framework focused on resurfacing projects and used treatment-specific simple linear regression based on lane miles and geographic location. The second addressed a broader group of construction projects and used multiple linear regression with project length, route type, and right-of-way cost as key predictors. In both frameworks, the final estimates are computed by aggregating multiple estimates produced by county-, region-, and state-level models. The …

Discrete-Event Simulation: A Leslie System Model For Transportation Demography, Md Zobaer Ahammad

Electronic Theses and Dissertations

Transportation systems are influenced by demographic change, household formation,and patterns of vehicle ownership. These factors affect long-run transportation demand and congestion levels within urban infrastructure. Understanding how demographic dynamics interact with transportation behavior is therefore important for analyzing the long-term evolution of transportation systems. This thesis develops a modeling framework that integrates discrete-event simulation with a Leslie-type matrix model to study transportation–demography interactions.Simulation outputs are aggregated to construct a transition matrix describing changes in transportation states. This matrix acts as a linear (or affine) transformation on the transportation state vector, allowing the system to be analyzed as a discrete linear …

Ai Institute Summer Camp Webinar Summary, Dora Nguyen

Paul English Applied Artificial Intelligence (AI) Institute Publications

This report summarizes the AI Institute Summer Camp informational webinar hosted by the Paul English Applied Artificial Intelligence Institute (PEAAII) at the University of Massachusetts Boston. The webinar introduced the structure, curriculum, learning objectives, and student outcomes associated with the 2026 AI Institute Summer Camp. In addition to summarizing the webinar content, this report analyzes participant questions, engagement trends, and areas of audience interest. Findings indicate strong interest in coding accessibility, mentorship opportunities, student outcomes, research experiences, and program flexibility. The report also identifies opportunities for improving future webinar delivery, including expanded eligibility guidance, pre-camp learning resources, enhanced presentation of …

Decomposition And Spectral Characterization Of Unsteady Loads In Pulse-Jet Propulsion Testing, Cesar Benitez

Theses and Dissertations

Pulsed jet propulsion systems produce inherently unsteady forces whose time-resolved characterization is essential for performance assessment, yet the measured load signal conflates aerodynamic forcing with the dynamic response of the measurement balance itself. This thesis develops a load centered framework for the dynamic characterization of a pulsed jet system, treating the measured load fluctuation as the primary physical observable rather than attempting full true-thrust reconstruction. A single-degree-of-freedom balance model identified through ringdown testing provides the structural reference scale, yielding a natural frequency of 8.5 Hz and damping ratio of 18%. Power spectral density, phase-averaging, and synchronous–residual decomposition is applied uniformly …

Exploration Of Extended Chemical Reaction Networks, Ramiro Santos

Theses and Dissertations

Chemical Reaction Networks (CRNs) is a well-established model for analyzing distributed and concurrent systems. A central problem studied across CRNs is the reachability problem, which asks whether a target configuration can be obtained from a given initial configuration through a sequence of valid transitions. Classical CRNs are highly expressive but not Turing-universal; their reachability problem is Ackermann-complete, indicating extremely high computational complexity that nevertheless falls short of full universality.

In this thesis, we study Extended Models of Chemical Reaction Networks in which the dynamics of the system are modified. We analyze these models through two fundamental questions. First, simulation, we …

Vision-Language Guided Quadruped Navigation With Reinforcement Learning Control, Chen Yuan Wang

Theses and Dissertations

Large Language Models and their multimodal variants, Vision-Language Models (VLMs), can interpret natural language instructions and visual context. Reinforcement Learning (RL) methods such as Proximal Policy Optimization (PPO) have been shown to successfully learn stable quadruped locomotion. This work investigates whether a VLM integrated with an RL controller can control a quadruped robot to perform instruction-following navigation to a predefined target using text instructions, egocentric vision, and proprioceptive state.

Most VLM-based robotics work directly target prediction of robot actions from multimodal inputs. This approach often depends on large amounts of expert demonstration data, generated by controllers such as trained RL …

Using Siamese Neural Networks To Effectively Detect Trojans In Fpgas When Trojans Manipulate Encryption Operations At The Bitstream Level, Kylie Arnett

Graduate Theses and Dissertations (2019 - present)

This research investigates security vulnerabilities in Field-Programmable Gate Arrays (FPGAs) at the bitstream level, focusing on hardware trojans (HTs) that manipulate encryption operations. This study addresses two critical questions: (1) The feasibility of exploiting FPGA bitstreams to selectively bypass encryption operations when a predefined input pattern is observed (all ones), thereby exposing sensitive data, and (2) the efficacy of Siamese Neural Networks (SNNs) in detecting such trojans with high accuracy. FPGAs are vulnerable to malicious modifications during manufacturing or deployment, posing risks to data integrity and system functionality. In this work, a trojan is inserted into a Xilinx series-7 FPGA …

Polyglot File Detection For Forensic Investigations, Chase Stevens

Graduate Theses and Dissertations (2019 - present)

As technology has become far more ubiquitous over the years, so too has the amount of digital evidence that can and needs to be collected and processed. Forensic tools are developed in response to the growing need, but are limited to what they are programmed to do. One such forensic tool is Autopsy, one of the most widely used open-source tools. Autopsy uses known file-type signatures (e.g., headers, trailers) to identify and recover files from forensic images. Polyglot files introduce a unique problem to both these forensic tools and investigators alike. In the context of the research conducted, polyglot files …

Detecting Sophisticated Cyberattacks On Public Water Infrastructure, Ayrton Purdy

Graduate Theses and Dissertations (2019 - present)

In recent years there has been an increasing number of cyberattacks on public water generation and distribution systems. Advanced persistent attackers could usurp sensors and control systems to contaminate public drinking water. In order to conceal their malicious activity, they can manipulate sensor data flows to give the appearance of normal activity. The compromised sensors would report normal chemical levels even though unsafe water is entering the distribution system. In response, this research proposes a multi-sensor, cross-comparison approach to anomaly detection. The proposed approach is designed to detect sophisticated cyberattacks which are not easily detectable using traditional cyber tools. The …

Developing A Framework For Microchip Design Recovery, Eric Diep

Graduate Theses and Dissertations (2019 - present)

Due to the increase in diverse chip production over the past decade, reverse engineering has become a difficult and daunting task. This research develops a methodology for microchip design recovery, seeking to validate and reproduce prior approaches to physical reverse engineering using low-cost tools and techniques. We used mechanical hardware abrasion tools and techniques to delayer and capture silicon integrated chip (IC) layout. We focused on the Mifare Classic EVl microchip, commonly implemented in public transit/transportation cards, to extract information for design recovery. The research explores limitations and advantages of mechanical abrasion and optical microscopy in context to modem chip …

Manufacturing Systems: Characteristics And Dynamics, Alan J. Fitzmorris

Graduate Theses and Dissertations (2019 - present)

This research answers three basic questions. First, what are the behaviors (dynamics) of a manufacturing system in the context of system performance? Are these dynamics best described as linear deterministic, periodic, nonlinear deterministic, or stochastic? Second, what are the complexity (chaotic) characteristics of a manufacturing system, namely the maximal Lyapunov exponent, correlation dimension, and Kolmogorov-Sinai entropy? Third, is there a relationship between complexity characteristics and manufacturing system performance? This research involves four high level steps: data analysis, system dynamics analysis, system complexity analysis, and correlation analysis. The data analyzed consists of concrete plant and shipbuilding shop time series performance data. …

Perceptions Of The Teacher Excellence And Accountability For Mathematics And Science Act On Rural Secondary Math Teachers' Practices, Motivation For Professional Development, Collaboration, And Job Satisfaction, Katina Stallworth

Graduate Theses and Dissertations (2019 - present)

The persistent shortage of qualified secondary mathematics and science teachers in rural schools has prompted states to adopt incentive-based policies aimed at improving teacher recruitment and retention. In Alabama, the Teacher Excellence and Accountability for Mathematics and Science (TEAMS) Act was enacted in 2021 to address these shortages through substantial salary supplements tied to professional development requirements and the relinquishment of tenure protections. While early reports indicate that the TEAMS program has increased the number of credentialed STEM teachers in classrooms, less is known about how participation in the program influences teachers' instructional practices, motivation for professional development, collaboration, and …

Narcissism And Eyewitness Identification, Haley M. Hearn

Graduate Theses and Dissertations (2019 - present)

According to the Innocence Project, 69% of individuals exonerated by DNA evidence were initially found guilty due to an eyewitness misidentification (Innocence Project, n.d.-a). A way that investigators attempt to prevent misidentification is by assessing how confident eyewitnesses are in their identifications. There is a large body of research suggesting that these confidence estimates can, in many instances, operate as reliable barometers of accuracy. However, what if an eyewitness is overconfident? Narcissism is a personality trait characterized by overconfidence. If a narcissistic eyewitness reports confidence in their identification of a suspect, should this report be trusted? Two studies were conducted …

Career Aspirations Of Generation Alpha In A Changing World: Perspectives Of Students, Parents, And Educators In Religiously Affiliated Private Schools, Cynthia Susan Grace

Graduate Theses and Dissertations (2019 - present)

This qualitative case study served as a needs assessment to examine how students, parents, and educators perceived and influenced career development within a contemporary high school context, with particular attention to Generation Alpha as its oldest members entered secondary education. To contextualize the study, research on prior generations and evolving career trajectories was reviewed to better understand the shifting landscape shaping this cohort's development. The study was grounded in Social Cognitive Career Theory (SCCT; Lent et al., 1994) and informed by a values-based perspective of purpose, examining the interaction between individual beliefs, contextual influences, and emerging career pathways. Data were …

Passive Microwave Remote Sensing Of Flash Drought Impacts On Vegetation, Quinton R. Deppert

School of Natural Resources: Dissertations, Theses, and Student Research

In 2002, Dr. Mark Svoboda characterized a new form of drought known as flash drought. Flash drought was defined as a rapid decline in vegetation health caused by severe heat and drought. In recent years, attempts to quantify the impacts of flash drought via precipitation, soil moisture, evapotranspiration, and temperature indicators have proliferated. What has rarely been quantified is what the rapid decline in vegetation health amid flash drought looks like through remote sensing. This is because vegetation health indices like the Normalized Difference Vegetation Index (NDVI) are derived from the visible and infrared regions of the electromagnetic spectrum and …

Enhancing Food Security In Stann Creek, Belize Using Meat Rabbits: Engineering Perspective, Lindsey Garretson

Biological and Agricultural Engineering Undergraduate Honors Theses

The purpose of this paper is to discuss the engineering perspective within the overall project of using meat rabbits to enhance food security and nutrition within Stann Creek, Belize. From the engineering perspective, the overarching goals were like the overarching project goals including the construction and materials required guide within the manual, designing potential upgrades to the design including a solar and battery system and an automatic watering system, and to design the system to be “practically sustainable” where possible. The constraints for this project included cost, the size of land dedicated for the rabbitry, and the operational and environmental …

A Concerted Effort: How The Roberts Court Demolished Anti-Gerrymandering Protections, Samuel Ogden

Seattle Journal for Social Justice

No abstract provided.