Digital Commons Network^™

Improving Quality Of Experience With Http/3 And Extensible Prioritization Scheme, Abhinav Gupta

Doctoral Dissertations

The internet is an indispensable part of modern life, with billions of users accessing countless web pages daily. While loading speed is crucial, the overall Quality of Experience (QoE) significantly influences user satisfaction and engagement with websites. Incomplete or delayed page loading can lead to frustration, reduced site visits, and financial losses. In our preliminary study, we examined how network protocols like HTTP/2 and HTTP/3 impact both Quality of Service (QoS) and QoE by assessing throughput and six Lighthouse performance metrics. Our findings highlight the relationship between QoS and QoE, emphasizing the need for efficient resource scheduling and prioritization to …

Dimensions Of Green Crabs, Carcinus Maenas (Linnaeus 1785), And Oysters, Crassostrea Virginica (Gmelin 1791), In Great Bay Estuary, New Hampshire, Kelsey Meyer

Doctoral Dissertations

Invasive species may alter how an ecosystem functions, such as the Great Bay Estuary (GBE) inNew Hampshire. In GBE, an invasive species of particular interest is the green cab (Carcinus maenas) because historically (and currently) there are no mitigation or eradication plans that have been implemented. It is not well-known how green crabs are interacting with oysters in GBE, whether that be wild, restored, or aquacultured. The aim of this dissertation was to document NH oyster growers’ perspectives on the issue of green crabs and oyster predation, understand their abundance, distribution and diet among natural/restored oyster areas and oyster farms …

Dynamic Defense Strategies For Field Programmable Gate Array (Fpga) Security, Sandeep Sunkavilli

Doctoral Dissertations

Field Programmable Gate Arrays (FPGA) have gained popularity and usage in recent years, and they have been widely used in mission-critical applications. Due to its popularity, the security of FPGA has become a big concern. Most existing research on FPGA security focuses on hardware Trojans, side-channel attacks, and reverse engineering. The existing FPGA countermeasures against the attacks above are typically limited to the FPGA systems implemented in the old FPGA utilization model. An increase in cloud-based FPGA providers, third-party accelerator suppliers, and open-source FPGAdesign tools has changed the FPGA utilization model, which requires new security measures for modern FPGAs. This …

Analysis And Procedures For Conducting Laboratory And Field Dielectric Measurements For Asphalt Pavement Density Evaluation, Anh Tran

Doctoral Dissertations

Achieving proper asphalt concrete pavement density, through combination of rigorous field and laboratory practices, is one of the top priorities of state agencies and contractors due to its significant impact on pavement performance and longevity. The field and laboratory traditional methods have limitations and pose challenges in terms of equipment and measurements which can influence the accuracy and efficiency of pavement density evaluation. In the field, various methods such as field coring, nuclear and non-nuclear density gauges are costly, time-consuming and only provide limited coverage of density assessment. In the lab, methods for evaluating the bulk specific gravity (Gmb) of …

Investigation Of Elastin-Like Polymer Surfaces By Electrochemical Impedance Spectroscopy In Redox Mediated And Non-Redox Mediated Electrolytes, Stanley Grant Feeney

Doctoral Dissertations

As the biomedical engineering industry grows, so does the need for on-line, continuous monitoring of specific biomolecules in industrial bioreactors. Elastin-like polymers, a thermoresponsive, protein-based macromolecule that mimics the behavior of the naturally occurring elastin protein, may hold the answer in the form of their stimuli-responsive conformation change. Surface-bound ELPs still require characterization, especially under conditions relevant to on-line sensing in bioreactors. The protocol for fabricating ELP-modified electrodes needs to be fine-tuned for reproducibility, with careful consideration for physisorption. Additionally, bioreactors require carefully controlled environments, without the presence of exogenous reagents. Therefore, the stimuli-responsive behavior of ELPs will need to …

Design And Synthesis Of Single Atom Catalysts For Solar Fuel Generation, Allison Harper St. John

Doctoral Dissertations

Solar fuel generation from photocatalytic carbon dioxide (CO2) reduction is a growing area of interest to mitigate global energy and climate crises. Graphitic carbon nitride (C3N4) is a light-absorbing semiconductor with a promising outlook for solar fuels, gaining popularity in recent years due to its low cost and appropriate band positions for many environmentally relevant reactions. The addition of atomically dispersed single atom catalysts (SACs) to semiconducting materials is a viable strategy for creating active sites to improve photocatalytic performance of the semiconductors studied. Designing C3N4 materials as a support for SACs with well-defined binding motifs and sufficiently high concentrations …

Responding To Range Expansion: Assessing Insect Communities, Tree Decline Symptoms, And Tree Mortality Risk As The Southern Pine Beetle Moves North, Caroline Rachel Kanaskie

Doctoral Dissertations

Climate change is shifting species distributions. In New England, warmer winters allow southern species to survive further north. The northward range expansion of the tree-killing southern pine beetle is the focus of this dissertation. Outbreaks of this beetle cause both ecological and economic damage, which threaten the globally rare pine barrens ecosystem. I used an interdisciplinary approach to study this insect: 1) I synthesized literature on the beetle’s natural enemies; 2) I used a suite of chemical attractants to investigate the insect community attracted to the beetle’s pheromones and assessed the diversity and abundance of its potential predators; 3) I …

Molecular Simulation Studies Of Peptide Transport Across The Mitochondrial Membrane, Son Nguyen

Doctoral Dissertations

Molecular transport across membranes is an important biophysical process. Designing molecules capable of crossing cell membranes and targeting specific organelle is becoming necessary in treating many diseases and disorders. In recent decades, cell-penetrating peptides have been studied and utilized to deliver a variety of cargoes. My dissertation work focuses on studying the molecular details of the peptide translocation process across a cell membrane. Specifically, I investigated the dynamics of mitochondrial-targeting peptides and their mechanisms of translocation across the mitomembrane. I conducted molecular dynamics (MD) simulations of model mitochondrial-targeting peptides with distinct physical and chemical properties such as sequence lengths, functional …

Investigating The Role Of Soundscape Properties And Genetic Material As Sentinel Indicators Of The Acoustic Environment In Gulf Of Maine Coastal Marine Ecosystems, Grant Alexander Milne

Doctoral Dissertations

ABSTRACT By identifying soundscape properties and taxa detected with metabarcoding that accurately predict substrate composition, assumptions about propagative properties of the environment can be rapidly formed without the use of active acoustic sensing or invasive environmental sampling techniques. “Sentinel indicators,” are variables, processes, or components within ecosystems that can be measured or quantified and have sensitivity to environmental pressures. Passive acoustic monitoring (PAM) and metabarcoding of seawater samples (MSS) are two minimally invasive potential methods of identifying sentinel indicators of soundscape and propagation properties of marine habitats by detecting the presence of marine taxa and extracting information from soundscapes. To …

Multiscale Materials Characterization And In-Situ Process Monitoring In Additive Manufacturing Via Non-Contact Optical Thermometry Techniques, Rifat-E-Nur Hossain

Doctoral Dissertations

While additive manufacturing (AM) is experiencing rapid growth, its development is uneven across different branches. Some areas are still emerging, while even the more established branches are still facing ongoing challenges that require further development. Regardless of their development stage, both emerging and mature AM require process monitoring and part characterization. Process monitoring helps to achieve more control over the process and build a self-adaptive system, while characterization of printed parts speeds up process optimization and ensures required quality. Together, process monitoring and build characterization will transform AM into a more dependable and commercially viable technique. Build surface temperature is …

Solid-State Crystallization Of Zeolites And Their Use In Plastic Upcycling Applications, Yixin Liao

Doctoral Dissertations

Plastics have been an irreplaceable component of modern technology as well as everyday life. They have brought much convenience to us with their characteristics of great malleability, durability, and stability. The versatile and low-cost nature of plastics also enables their wide engagement in many modern industries including automobile, medical, communication as well as aerospace. Polyethylene (“PE”), made from polymerization of ethylene, is one of the most widely used plastics in the world. Being cheap, flexible, and long-lasting, they are extensively used in the packaging industry, especially for plastic bags and other sorts of containers. However, the durability of plastics, on …

Smoothed Particle Hydrodynamics For Free-Surface Flows And Time Series Forecasting Approach For Computational Fluid Dynamics, Huali Ye

Doctoral Dissertations

With the increase in computing power, numerical simulation has become an essential approach to solving problems in engineering and science. Numerical simulations provide a platform for theoretical validation and facilitate novel discovery. Even though extensive mesh-based numerical methods are utilized, significant limitations exist, particularly in Computational Fluid Dynamics (CFD). Because of the grid distortion, issues related to large deformations, moving interfaces, and free surfaces may lead to considerable computational errors, constraining their efficacy in numerous applications. As a mesh-free method, Smoothed Particle Hydrodynamics (SPH) was introduced in 1977 and has been widely applied in many fields such as astrophysics and …

Real-Time Prediction Of Dynamical Systems Using A Hybrid Analog Computer: Network Traffic Modeling, Majd Zuhair Tahat

Doctoral Dissertations

As the number of online users grows exponentially, the number and severity of cyber threats escalate, urgently requiring advancements in real-time network modeling and response. Swiftly predicting and analyzing network traffic is crucial for effective network monitoring and control, preventing cyber breaches, and maintaining healthy network functionality. This research presents a novel approach to real-time modeling based on analyzing evolving properties and patterns in a dynamical network system using a hybrid analog-digital computer. An analog computer was utilized as a co-processor to compute differential equations that model the Transmission Control Protocol (TCP) window size. A comparative analysis was conducted between …

A Human-In-The-Loop Framework For Scalable And Interpretable Event Triaging In Large-Scale Systems, Ibrahim Khaled Al-Agha

Doctoral Dissertations

This dissertation presents a comprehensive and scalable framework for real-time fault detection and event triage in industrial systems, addressing critical challenges such as class imbalance, ambiguous feature boundaries, and the prioritization of complex, high-dimensional event data. The proposed framework integrates advanced methodologies, including micro-batch processing, retrospective divergence-based event detection (DB-RED), association rule mining (ARM), clustering, and Dempster-Shafer Theory (DST) for conflict resolution. Together, these components enable the systematic stratification of events into actionable priority levels, ensuring robust and interpretable decision-making in real-time environments. DB-RED forms the cornerstone of the framework, leveraging KL-divergence and PE-divergence metrics to detect subtle and transient …

Creating A Framework To Develop Project-Based Platforms To Support Engineering And Technology Education, Casey Daniel Kidd

Doctoral Dissertations

Engineering education has evolved over the last few decades to increasingly include project-based learning (PBL) throughout the curriculum to give students more hands-on experience. However, there can be a hesitancy from faculty and instructors to move from traditional lectures to PBL-based curricula. Research has been conducted to identify barriers to research-based instructional strategies (RBIS), which include PBL. However, this research does not go into depth about the specific barriers for these individual RBIS. Furthermore, it has been found that the adoption of a new practice within a community has more success through a propagation paradigm, where the change agents are …

Application Of Artificial Intelligence Techniques To Improve Leadership Decision Making With Uncertainty, Michael David Parrish

Doctoral Dissertations

"Every good leader is a good manager, but not every good manager is a good leader. The difference between the leader and the manager is critical decision-making. Today’s decision-making environment is characterized as Volatile, Uncertain, Complex, and Ambiguous (VUCA). With the exponential increase in the technical capabilities of systems, the human has become the weakest link in the use of such systems. To remain relevant, good leaders must continuously adapt to new advances in technology and processes.

The research contributions of this work provide several unique and novel solutions for leaders to utilize artificial intelligence tools to improve and optimize …

Experimental Study Of Defects In Coaxial Wire-Based Laser Metal Deposition, Remy Mathenia

Doctoral Dissertations

This work seeks to improve the usability and capability of coaxial wire-based laser metal deposition (LMD) through the experimental study of process parameters on output geometry, directional effects, and defect formation. Wire-based LMD is a directed energy deposition (DED) strategy that uses a focused laser heat source to melt and fuse metal wire as it is deposited. This process is used to build parts layer-by-layer until a desired geometry is accomplished. LMD enables the creation of complex components at a high build rate with low material and energy waste. This work focuses on the deposition of titanium wire in the …

Development Of Dual-Scan Nuclear Magnetic Resonance (Nmr) Pulse Programs For Spin-Lattice Relaxation Measurements, Zachary Mayes

Doctoral Dissertations

This research develops and refines the Split Inversion Pulse and Recovery (SIP R) methodology for spin-lattice relaxation (T₁) measurements in NMR spectroscopy. SIP R introduces a two-scan difference technique using a split inversion pulse sequence, where the 180° pulse is split into two 90° pulses phase-shifted with respect to each other. This approach simplifies data fitting, requiring only two parameters to extract T₁ values, compared to the traditional inversion-recovery method, which needs three. The SIP-R-DS and SIP-R-S adaptations extend this framework by incorporating selective NMR resonance excitations, enhancing its applicability to cross-polarization experiments and enabling unobstructed NOE measurements. These adaptations …

Development, Characterization And Testing Of Traditonal And Advanced Nuclear Fuel Cladding Materials, Joshua Eddy Rittenhouse

Doctoral Dissertations

Kanthal D and FeCrAl alloys in general, are prospective candidates as accident tolerant nuclear fuel cladding materials. The work presented herein focuses on applying two techniques of severe plastic deformation, equal channel angular pressing (ECAP) and high-pressure torsion (HPT), as means of grain refinement to improve irradiation resistance. Samples of as-received, ECAP, and HPT processed Kanthal D were exposed to neutron irradiation to a dose of 2 DPA at two different temperatures, 300 °C and 500 °C. Detailed characterization was performed including mechanical and microstructural, and several positive improvements with regards to irradiation resistance were identified in the ECAP and …

Design And Synthesis Of Organocatalyts For Efficient Decontamination Of Organophosphate-Based Nerve Agents And Pesticides, Emmanuel Kingsley Darkwah

Doctoral Dissertations

Exposure to organophosphate-based nerve agents and pesticides poses significant health and security threats to civilians, soldiers, and first responders. Despite extensive efforts to develop chemical detoxification agents for use in topical applications on exposed skin surfaces and for intravenous injections, there remains an unmet need for effective, non-hazardous decontaminating agents. The current state-of-the-art decontaminating agent, Dekon-139 (2,3-butanedione oxime, potassium salt), exhibits adverse effects when applied to the skin.

In this study, we designed and synthesized pharmaceutically relevant aminoguanidine-derived aldimines that are relatively non-toxic and substantially more effective at decontaminating nerve agents and pesticides compared to existing agents, and they act …

Deep Learning Architecture Design For Nano-Satellite Image Super-Resolution, William Everette Symolon

Doctoral Dissertations

Increasing threats to U.S. national security satellite constellations have resulted in an increased interest in constellation resilience and satellite redundancy. NanoSats have contributed to commercial, scientific and government applications in remote sensing, communications, navigation, and research. They also have the potential to enhance satellite constellation resilience. However, the inherent size, weight, and power limitations of NanoSats enforce constraints on imaging hardware; the small lenses and short focal lengths result in imagery with low spatial resolution, which limits the utility of CubeSat images for military planning purposes and national intelligence applications. This research proposed a deep learning architecture capable of enhancing …

The Impacts Of Social Media On Teacher Environment Perceptions, Victoria Puglia

Doctoral Dissertations

Social media significantly influences teachers’ perceptions of their professional environment, shaping job satisfaction, respect, autonomy, and professional support. This dissertation, split into three articles, investigates how exposure to positive, negative, or mixed social media posts impact these perceptions, addressing concerns surrounding teacher well-being and attrition in K-12 education. The study began with a literature review in Article 1 to establish a theoretical framework, followed by a series of validation steps to refine a survey instrument aligned with teaching perception constructs in Article 2. The final survey was administered to 406 K-12 teachers across the United States in Article 3, using …

Phase-Field Modeling Of Rapid Solidification Processes, Nima Najafizadeh

Doctoral Dissertations

"Many advanced manufacturing processes such as additive manufacturing utilize rapid solidification of alloys, as it enables the formation of exotic non-equilibrium microstructure and thus improved properties. However, the interrelationship between the processing parameters and the resulting microstructure in rapid solidification is yet to be fully understood. We aim to investigate the microstructure evolutions during the rapid solidifications using phase-field modeling. The phase-field method assumes a diffuse interface, which avoids tracking the moving interface and hence enables efficient numerical simulations for complex microstructure evolution. A phase-field model with coupled solute-thermal diffusion and solute trapping effect is developed to investigate the rapid …

Drone-Based Multimodal Sensing On Vegetations And Data Analytics For Early Detection Of Gas Leakage From Underground Pipelines, Pengfei Ma

Doctoral Dissertations

"This study explored the feasibility of using multimodal remote sensors in the early detection of natural gas leaks from underground pipelines, as vegetation situated above pipelines can discern microbial changes in soil when affected by gas and exhibit physiological stress symptoms on leaves. Three sensors (RBG, thermal, and hyperspectral cameras) were utilized to monitor vegetation stress as an indicator of gas leaks. A laboratory experiment was conducted to evaluate the workability of vegetation for gas leak detection. Regular hyperspectral imagery was collected from test vegetations to identify gas stress and distinguish it from other environmental stressors such as salinity impact, …

Processing And Densification Of Multi-Phase High-Entropy Ceramics, Steven Smith

Doctoral Dissertations

"This work focuses on the processing and densification of multiphase, high-entropy ceramics to promote their use in friction stir welding technologies. Several high-entropy systems including high-entropy borides, carbides, and their composites were produced. Boro/carbothermal and carbothermal synthesis were used to produce high-entropy powders from oxide powder mixtures. Composites of high-entropy borides and high-entropy carbides were produced using a sequential approach to produce both phases. The carbide was first produced using carbothermal reduction, then ZrH2 and B4C were added to the carbide powder to produce the high-entropy boride phase. The resulting powder was densified by spark plasma sintering and pressureless sintering, …

Raft-Based Polymer And Nanoparticle Materials For Traumatic Brain Injury Treatment And Diagnostics, Aaron Priester

Doctoral Dissertations

"Traumatic brain injury (TBI) is a leading cause of death and disability worldwide. Neurodegenerative diseases that develop post-TBI can be, in part, attributed to DNA and cell-damaging reactive oxygen species (ROS) and lipid peroxidation products (LPOx). This thesis focused on overcoming the limits of current TBI material treatment approaches by employing a RAFT (reversible-addition fragmentation chain transfer) polymer approach that incorporated novel therapeutic, diagnostic and peptide-targeting monomers. An improved nanoparticle synthesis approach was also developed. Thiol and thioether-containing monomers neutralize both ROS and LPOx while Gd-containing monomers with enhanced magnetic resonance imaging (MRI) contrast provide diagnostics and material tracking in …

The Evolving Use Of Strategic Planning Tools In The Manufacturing Environment: Implications For Quality 4.0 And Beyond, Richard Lee Wilson

Doctoral Dissertations

"Having a strong strategic plan is critical for success for any business no matter the size of the organization, the product or service they provide, or the industry they serve. There are many methods businesses use to develop their strategic plans. One such method is known as Hoshin Kanri, which has been in use for decades. However, recent years have seen an increase in artificial intelligence, big data, data analytics, and other technology tools to create cyber physical systems on the manufacturing floor. The increase in technology in manufacturing to integrate cyber systems with physical systems spawned a new industrial …

Shock Wave And Vortex Ring Dynamics From Explosively Driven Shock Tunnels, Rachel Louise Bauer

Doctoral Dissertations

"Blast and shock tubes are frequently used to create shock waves to study their effects and impacts on structures, humans, and personal protective equipment. These tubes are also found in other industries including wind tunnels for aerodynamic testing, jet engines for propulsion research, spacecraft reentry simulations, and industrial applications such as material testing and high-velocity impact studies. Despite their widespread use, there is no standard design, with variations in geometry, size, and energy sources. Current research only evaluates the peak pressure of the shock wave produced and does not consider the effects of changing the size or geometry of the …

Transport And Plugging Behavior Of Co2-Resistant Preformed Particle Gels In High Conductive Channels For Conformance Control, Adel Alotibi

Doctoral Dissertations

"Improving oil recovery is essential with rising global oil demand and declining production in mature fields. CO₂ flooding has been widely applied as a major Enhanced Oil Recovery (EOR) method due to its effectiveness in boosting oil recovery while enabling safe carbon storage in the subsurface. However, in fractured and highly heterogeneous reservoirs, CO₂ often flows through paths of least resistance, leading to early breakthrough or quick excessive CO₂ production and leaving substantial oil in unswept zones or areas. Traditional in-situ polymer gels have been applied to control CO₂ flooding conformance, their performance has been varied, …

Development And Testing Of Irradiation-Tolerant High-Entropy Alloys, Matthew John Luebbe

Doctoral Dissertations

"High entropy alloys (HEAs) are a novel class of alloys made of multiple principal elements in near equal proportions. They have been observed to possess an array of useful engineering properties, such as good ductility and fracture toughness, high temperature strength, oxidation and corrosion resistance and irradiation resistance. This makes them promising candidates for harsh environments, especially nuclear reactors. These properties could potentially realize advanced Gen IV nuclear reactor designs. However, most HEA compositions contain Co, which activates under irradiation, generating safety and waste management concerns. This work studies three compositions of Co-free HEAs whose strength and microstructures are evaluated …