Digital Commons Network^™

Autism Spectrum Disorder, Vidhya Lakshmi Jeevarathinam

Electronic Theses, Projects, and Dissertations

Autism Spectrum Disorder (ASD) diagnosis requires an integrative approach that combines behavioral, biomedical, and computational methodologies for enhanced accuracy. This study introduces a comprehensive framework that employs machine learning (ML) and deep learning (DL) techniques alongside linear regression to model relationships between behavioral traits, biomedical markers, and ASD likelihood. Behavioral inputs, such as social interaction patterns, repetitive behaviors, and communication characteristics, are analyzed using linear regression to identify significant predictors of ASD. Simultaneously, a Convolutional Neural Network (CNN) is trained on image datasets to detect visual cues, such as facial expressions, associated with ASD. Advanced techniques, including transfer learning and …

Prediction Of Dislocation Density During Casting Of 316 Stainless Steel Based Alloys As A Function Of Chromium And Nickel Composition, Abhishek Chitradurga Ranganath

All Theses

By the 1990s, computational methods were beginning to be used to study dislocation density in mental casting. Prior to that time research was based heavily on laboratory studies. This move was encouraged by the need to overcome limitations that experimental approaches had, including high costs and time-consuming processes, and needs of researchers to understand atomic-scale phenomena. Computational techniques allow complex materials to be simulated in cost effective way and can provide insight into behaviour that could never be determined through experimental methods alone.

This work utilized molecular dynamics (MD) simulations along with machine learning approaches to examine the dislocation density …

Application Of Lossy And Lossless Compression To Dicom Files, Yizhe Yang

All Theses

The Digital Imaging and Communications in Medicine (DICOM) standard is widely utilized for the management, storage, and transfer of medical images. However, the substantial file sizes associated with DICOM data present challenges in terms of storage and data transmission. Data reduction techniques help address these challenges by minimizing the size of the data while preserving its integrity. This thesis examines various compression methods aimed at reducing the size of DICOM files. We evaluate five lossless compressors and four lossy compressors on DICOM data to compare and assess their performance. Through an analysis of each compressor’s compression efficiency and resulting image …

Microbial-Chemical Degradation Of Styrene In Co-Mingled Plumes With Ethylbenzene, Benzene, And Carbon Tetrachloride, Marcela C. Flórez-García

All Theses

Industrial sites contaminated with a complex matrix of chemicals represent a problem for the ecosystem and a high risk for the health of all individuals. That is why remediation strategies are needed to mitigate this environmental impact. The latex zone, located at the Corteva industrial site in San Lorenzo, Argentina, is the subject of this research. The environmental impacts in this area are a consequence of petrochemical operations carried out for many years.

Monoaromatic hydrocarbons such as styrene, ethylbenzene, and benzene, and chlorinated methanes like carbon tetrachloride, chloroform, dichloromethane, and chloromethane are among the contaminants identified at the site that …

Effects Of Concrete With The Implementation Of Spent Coffee Grounds, Nathan Limon

Construction Management

During this study, compression tests were performed on three different concrete mix designs to evaluate the effects of spent coffee grounds as an admixture. The initial mix design was the control mix, composed of a general concrete mix design containing aggregate, cement, and water. The second mixture utilized was high strength concrete; this included aggregate, cement, and water, fly ash. The third mixture tested consisted of aggregate, cement, water, and spent coffee grounds. The purpose of evaluating these three different mixtures is to see whether spent coffee grounds can be implemented into concrete without compromising the compressive strength. Substituting 15% …

Assessment Of Pedestrian Safety At Roundabout Slip Lanes: A Study On Design Configurations And Surrogate Safety Measures, Norran Kakama Novat

Masters Theses

The implementation of slip lanes at roundabouts has been widely adopted to improve traffic flow and reduce vehicle conflicts. However, the presence of slip lanes introduces significant risks for pedestrians, influencing vehicle speeds, merging behaviors, and increasing the potential for pedestrian-vehicle conflicts. This study investigates pedestrian safety at roundabouts with various slip lane designs, focusing on their impact on vehicle speeds, pedestrian-vehicle conflicts, and yielding behavior. Also, the study evaluates commonly used surrogate safety measures by employing extreme value models to assess their efficiency.

The study addresses two primary objectives: (1) analyzing the effects of different slip lane configurations on …

Using Nano-Ities For Detection Of Metal Ions In Complex Aqueous Solutions, Mohammed Muzammil Nishar Ahmed

Theses and Dissertations

Recent urbanization has induced a rapid increase in heavy metal exposure to humans. The exploitation of heavy metals for economic gains coupled with poor and economically infeasible recycling methods have led to poor management of heavy metal wastes, which has opened up several pathways for heavy metals to enter the human body. Such heavy metals target many vital organs, but the early symptoms are common and difficult to diagnose. Severe symptoms appear in later stages and are very expensive to treat and the damage caused to the health are not typically reversable in such later stages. To counter this issue, …

Adsorption Of Harmful Algal Bloom Toxins Using Biochar, Cadianne Chambers

Theses and Dissertations

Harmful Algal Bloom (HAB) events involve the proliferation of microalgae which discharge lethal toxins into fresh and brackish water bodies due to anthropogenic and climatic activities. Common examples of HABs include causative organisms such as Cyanobacteria, Pyrodinium bahamense and more. These genera are known to release potent toxins including Microcystins, and Saxitoxins, respectively, which can seriously endanger human and marine health. Ingestion of these toxins can result in several health problems, such as nausea, vomiting, gastroenteritis, skin irritation, liver damage, paralysis, and respiratory arrest. The Great Lakes, Gulf of Maine, Florida’s coasts, Lake Erie, and Lake Okeechobee have all been …

Tac-It An Affective Computing User Interface Design, Andrew Biron

Theses and Dissertations

TAC-IT affective computing user-interface design is an independent computer peripheral that is a tool to be utilized to obtain a user’s self-reported emotional state in real-time. Doctor Rosalind Picard first coined and used the term affective computing in her paper Affective Computing [Picard, R. (1995)]. Affective Computing is defined as the study and development of systems and devices that can recognize, interpret, process, and simulate human affects. It is an interdisciplinary field spanning computer science, psychology, and cognitive science. Since that time, areas of research have expanded exponentially, and areas of interest include how to trigger emotions in a test …

Theoretical Advancements In Hawkes Processes And Their Practical Applications, Xi Zhang

Theses and Dissertations

Hawkes self-exciting point processes have been widely used in fields such as seismology, finance and social media analysis. Despite decades of research focusing on these processes, several key aspects remain under-explored. These include broadly applicable methods for model evaluation and selection, intuitive nonparametric inference approaches akin to kernel density estimation for probability density functions, and strategies to enhance the performance of generative point process models in predictive tasks. In this dissertation, first, we extend the time-rescaling theorem, which is traditionally limited to non-terminating processes with complete observations, to accommodate terminating processes and incomplete observations as well. This extension allows for …

Advancing Biofabrication Methodologies To Develop Biomimetic Tissue Scaffolds For Musculoskeletal Applications, Nashaita Yezdi Patrawalla

Theses and Dissertations

Musculoskeletal injuries impose a significant global burden, affecting millions and generating an economic toll exceeding $14 billion. Tissue engineering has gained traction as a promising strategy offering potential for functional restoration of damaged musculoskeletal tissues. This research aims to advance biofabrication techniques for generation of biomimetic tissue scaffolds, by optimizing scaffold design and modulating fabrication process parameters to generate scaffolds for musculoskeletal regeneration with application-specific tailored properties. In this realm, collagen-based biomaterials have been extensively investigated for tendon and ligamentous applications, and in combination with bioceramics incorporated into the collagen framework to produce composite scaffolds that better recapitulate the native …

Zero-G Exercise Equipment, Charisse Biglete, Jake Brajevich, James Monroe, Ethan Siahpush

Mechanical Engineering

In a micro-gravitational environment, the body undergoes less loading than that found on Earth. This leads to muscular atrophy, Osteoporosis, decreases in protein synthesis, and various other undesirable outcomes. To prevent this, astronauts undergo a strict exercise regime to maintain their health. The current exercise equipment available for spacecraft is large, heavy, complicated to use, costly, and unsafe. There is a definite need for the re-engineering of the exercise equipment to be used by astronauts while in microgravity environments to rectify these issues.

Fabrication And Charcaterization Of Pullulan-Collagen Nanofibers Via Forcespinning, Valeria Leon Leal

Theses and Dissertations

Extensive research on collagen has spurred advancements in tissue engineering and biomaterial development, given collagen´s pivotal role in regulating various tissue structures across diverse organisms. This study delves into fabricating nanocomposites utilizing collagen, along with silver nanoparticles, chondroitin sulfate and pullulan, for potential applications in antibacterial medical devices, and cell regeneration. Collagen, abundant in the extracellular matrix, provides essential structural support, while silver nanoparticles and chondroitin confer antimicrobial properties, crucial for combating infections. Pullulan, a polysaccharide polymer, serves as a biocompatible carrier for silver nanoparticles whilst being the starting nanofiber forming material. Utilizing Forcespinning® technology, composite nanofibers were successfully synthesized. …

Recovery Resiliency Of Interdependent Power Systems Infrastructure Subject To Extreme Events, Partha P. Sarker

Graduate Theses and Dissertations (2019 - present)

When Hurricane Maria struck the island of Puerto Rico on September 20, 2017, it devastated the island’s aging power systems infrastructure and inflicted an island-wide power outage that left Puerto Rico in total darkness for an entire week before the system slowly started to recover. This unprecedented failure of the critical power systems infrastructure exacerbated the failure of other critical infrastructures or lifeline systems of the island. This research explores and quantifies the relationships or interdependencies that exist between the power systems and other critical infrastructure systems by investigating the post-hurricane recovery data of these lifeline systems. Subsequently, the research …

Cyclic Thermal Stability Of Native Oxide Solar Thermal Absorbers On Femnnialcr High Entropy Alloys For Energy Applications, Xiaoxue Gao

Dartmouth College Ph.D Dissertations

High entropy alloys (HEAs) are promising candidates for cost-effective high-temperature materials in high-efficiency power cycles. A potential application is in concentrated solar power (CSP) systems, where native oxides of cost-effective FeMnNiAlCr HEAs can also synergistically serve as a high-efficiency solar thermal absorber. However, the huge and repetitive temperature change of the CSP system in day-night cycles greatly challenges its thermal stability. In this thesis, we investigated the cyclic oxidation behavior of FeMnNiAlCr HEAs to improve the optical performance and thermal stability of their native oxides as a solar absorber for next-generation CSP systems. We found that the duplex oxide scale …

Bonsai Merkle Tree Streams: Bulk Memory Verification Unit For Trusted Program Verification System, Richard J. Rios

Master's Theses

Today, all modern computing systems are undoubtedly vulnerable to numerous types of attacks that could be targeted toward any layer of the system from dedicated hardware to highly abstracted software. Unfortunately, many devices and systems naturally contain inadequately protected components or software modules that un- dermine their security as a whole. Additionally, security is heavily variable system to system, and has a huge dependence on adequate implementation and ongoing support from device and software manufacturers. To address these various security issues in a very general way, TrustGuard, a containment security system utilizing an external device called the Sentry that would …

The Practical Adoption And Application Of Blockchain Technology Within The Beverage Industry, Alexander Adams Jr

Electronic Theses, Projects, and Dissertations

Abstract

The beverage industry is facing heightened scrutiny as the demand for transparency and accountability reaches new heights. In the age of information technology, companies must prioritize enhanced traceability to ensure product safety, comply with government regulations, maintain customer trust, and protect brand integrity. This thesis explores the potential of blockchain technology as a solution to these challenges, focusing on its ability to decentralize data, improve traceability, and expedite response times during safety recalls. The research provides an overview of the evolution of food safety regulations, beginning with the first establishment by Upland Sinclair, and examines current traceability practices and …

Nanostructured Silicon Meta-Waveguides And Surfaces For Enhanced Light-Matter Interaction, Saddam Gafsi

All Dissertations

In this study, we tackle the challenge of light-matter interaction engineering and local field enhancement using various silicon photonic platforms based on three different approaches. (i) The first approach is based on boundary condition engineering where we present and show through simulation and experimental results, a silicon nanodisk “diabolo” configuration able to support significant local field enhancement levels in the range ~102 to 104 in the high index medium through proper structural modifications at the nanoscale. We show that the presented optical behavior is consistent with the anapole modes characterized by the observed near-field enhancement and coinciding with far-field suppression. …

Optimization Of Polymeric Micelles As A Delivery System For Crispr/Cas9 Ribonucleoprotein, Lucian Williams

All Dissertations

Clustered regularly interspaced short palindromic repeats (CRISPR) is an adaptive immune system in bacteria that has been harnessed to perform precise genetic modifications in mammalian cells. Among CRISPR-associated (Cas) proteins, Cas9 has emerged as a transformative tool in gene editing due to its simplicity, high specificity, and versatility compared to the other Cas proteins and gene-editing technologies. Despite its potential to cure genetic disorders, the clinical application of Cas9 has been hindered by challenges such as immunogenicity, off-target effects, and low delivery efficiency. To address these issues, this dissertation explores using polymeric nanoparticle systems to encapsulate and protect Cas9 and …

Supporting Holistic, Informed, Decision-Making Through The Complementarity Of Life Cycle Assessment And Radiological Protection, Bryanna Wattier-Weisensee

All Dissertations

Decision making is challenging and it is necessary to consider all relevant data to make an informed decision. The work herein provides a pathway wherein the fields of radiological protection and life cycle assessment (LCA) can be utilized synergistically to benefit the decision-making using the other (and vice versa). Specifically, LCA parallels decision-aiding techniques used in the optimization of radiological protection and LCA includes an ionizing radiation potential (IRP) impact category wherein the impacts associated with an emission of radioactive material is quantified to determine the human health impact. Thus this body of work focuses on (1) expanding the platform …

Quantitative Evaluation Of Baseflow Separation Methods Using An Integrated Hydrologic Model: A Case Study In A Snow-Dominated Watershed, Jihad Othman

All Graduate Reports and Creative Projects, Fall 2023 to Present

Baseflow, commonly referred to as the groundwater contribution to streamflow, constitutes approximately 50% of streamflow in mountainous regions of the Western United States. Accurately quantifying the amount of baseflow is critical for water management and decision-making, as it significantly impacts stream water quality, low flow availability, and ecosystem health. Traditionally, baseflow has been estimated using conceptual and automated baseflow separation methods, which are known to be both arbitrary and ambiguous, posing a challenge to validate them. In this study, we developed an integrated hydrologic model that seamlessly integrated the exchange between surface and subsurface flows to physically quantify the baseflow …

Designing A Robust Lab Scale Electrocoagulation Reactor For Removal Of Micro- And Nanoplastics From Drinking Water, Emmanuel Louis Aduhene

All Graduate Reports and Creative Projects, Fall 2023 to Present

The widespread occurrence of micro and nanoplastics in drinking water sources could cause serious public health issues. These plastics particles, products of industrial operations and weathering of larger plastics, can interact with other contaminants in the environment, leading to more severe environmental pollution. Present drinking water treatment technologies were designed to remove suspended colloids. However, due to the distinct chemical and physical properties of micro and nanoplastics from conventional colloids, it is challenging for traditional chemical coagulation/flocculation/sedimentation process to achieve satisfying removal performance. This report investigates a design of a lab-scale electrocoagulation reactor for the removal of nanoplastics from drinking …

Engineered Microalgae Cultivations Systems: Conversion Of Wastewater Nutrients Into Biofuels And Bioplastics, Jacob Watkins

All Graduate Theses and Dissertations, Fall 2023 to Present

Dissolved Nitrogen and Phosphorus in wastewater can contribute to harmful algae blooms if released into the environment. One technology that can be used to recover dissolved nutrients from wastewater is the Rotating Algae Biofilm Reactor (RABR), which supports microalgae growth in an easily-harvested biofilm and produces nitrogenand phosphorus-rich biomass that can be used to produce slow-release fertilizers, biofuels, and compostable bioplastics. This thesis (1) examines the effects of several environmental factors on the biomass production rate and nutrient removal efficiency of RABRs treating municipal wastewater, (2) quantifies the composition and biofuel yields of microalgae biomass cultivated using a RABR at …

A Mass Balance Model Of The Great Salt Lake, Ut With Adaptive Management Applications, Diana Dunn

All Graduate Theses and Dissertations, Fall 2023 to Present

The Great Salt, Utah, USA is a saline lake that provides critical habitat for ecologic communities and generates $1.3 billion annually. It has gone through detrimental change since the 20^th century. Streamflow reaching the lake has been decreased by upstream withdrawal for industrial and municipal use, causing the lake level to drop and salinity to increase to unhealthy levels. Further, in 1959, it was segregated into north and south sections by a railroad causeway. Due to the causeway and limited exchange of water through two bridges, the lake sections have significantly different water surface elevation and salinity levels. The …

Channel Dynamics In Response To Compounding Hydrogeomorphic Disturbances In A Steep Burned Watershed, Paxton Ridgway

All Graduate Theses and Dissertations, Fall 2023 to Present

Wildfires significantly increase sediment input to rivers through various pathways, including post-fire debris flows. Understanding how mountain rivers respond to these sediment inputs is crucial for predicting and managing downstream impacts on infrastructure, water security, and aquatic habitats. While the causes and characteristics of post-fire debris flows have been extensively studied, the morphological changes in downstream fluvial channels remain poorly understood. This study uses scripted spatial analysis toolsets, high-resolution pre- and post-fire DEMs, repeat cross-sectional surveys, time-lapse footage, and pebble counts to document channel responses to sediment supply in a burned steep mountain stream in the upper Colorado River Basin, …

Barriers And Drivers To Bus Electrification: The Transit Agency's Perspective, Aleks C. Paskett

All Graduate Theses and Dissertations, Fall 2023 to Present

Battery-electric buses (BEBs) have become increasingly common in recent years, as transit agencies around the world seek to reduce their carbon emissions. Although many agencies and governments have set ambitious climate goals pushing for increased adoption of BEBs, some agencies face difficulty transitioning their fleets to this technology. This study seeks to understand the challenges faced by these agencies, as well as their motivations for adopting BEBs. Researchers conducted a series of interviewers with twelve transit leaders representing ten transit agencies who were leading BEB adoption programs, asking questions about their experiences trying to implement this technology. The interviewees stated …

Assessing Canopy Features, Its Shading Factor, And Their Influence In The Estimation Of Evapotranspiration In Almond Orchards Using Uas Information And The Two-Source Energy Balance Model, Moises R. Duran-Gomez

All Graduate Theses and Dissertations, Fall 2023 to Present

This study explored how canopy biomass and shadows affect evapotranspiration (ET) estimates, a crucial factor for irrigation management in almond orchards in California’s Central Valley. Data from 24 drone flights over three almond plots in 2021 and 2022 were analyzed using the Two-Source Energy Balance (TSEB) model, combined with meteorological data from EC-towers. The study found that filtering out shadows improved ET estimation, particularly in young orchards, and identified the importance of using new Leaf Area Index (LAI) models for better accuracy. This research is part of the T-REX initiative, which integrates drone and ground-based data to enhance water use …

Developing A Bioengineered Nanoparticle For Improving Oral Absorption Of Iron Supplements., Mila Biswas

Open Access Theses & Dissertations

Iron deficiency (ID) and iron deficiency anemia (IDA) are widespread nutritional issues, affecting millions globally. Conventional iron supplements often suffer from low absorption rates and gastrointestinal side effects. We investigated β-glucan derivatives as potential carriers to enhance iron absorption and mitigate these drawbacks. This study explored a novel β-glucan-based carrier system loaded with ferrous sulfate heptahydrate. In-vitro studies demonstrated sustained iron stability for over six hours in simulated gastric fluids due to the carrier's affinity for stomach mucin. Particle size analysis and scanning electron microscopy (SEM) images confirmed this specific binding. Additionally, drug release studies revealed a pH-dependent release profile, …

Accessibility And Usability Of Medical Devices For Users With Disabilities: Insights From A Bibliometric And Thematic Analysis, Karen Daniela Gonzalez Silva

Open Access Theses & Dissertations

No abstract provided.

Optimal Route Planning Considering Microlevel Sequence Of Delivery Task Using Computer Simulation, Dana Alejandra Zamorano Orozco

Open Access Theses & Dissertations

As globalization reshapes our industries worldwide, supply chain management has evolved into a highly interconnected world that oversees traditional management, making countries more interdependent. Driven by rapid technological advancements, this shift allows companies to share information in a matter of seconds across continents, aligning operations and building adaptability to quick changes. Therefore, industries have greatly needed to adjust to and use the new technology to their advantage. However, even when this impact can be observed globally, the general impact can be analyzed and eradicated by performing micro-level analysis within the supply chain using technologies to their advantage. AnyLogic is a …