Engineering Commons^™

Analytical Airflow Solution Of A Helicopter Engine Bay And Novel Bay Cooling Cowling Design, Daniel Evan Yastishock

Theses and Dissertations

The objective of this thesis is to develop an analytical-numerical solution for the engine bay cooling airflow in a representative helicopter based on the Augusta-Westland 101, and evaluate the performance of a novel rotating scoop cowling on the airflow. The methodology was created in PythonTM. Results obtained via the analytical method were compared against a CFD model constructed with Ansys® at a hover, 50 fps forward flight, and 250 feet per second forward flight using a k−ε turbulence model. Performance of the rotating scoop was compared to that of a conventional inlet orifice and fixed scoop in a similar airspeed …

Hydrogen/Diesel Co-Combustion In Compression Ignition Engines Through Hydrogen Ingestion And Direct Hydrogen Injection, Helge Hening Von Helldorff-Garn

Theses and Dissertations

This dissertation develops, implements, and validates the computational tools necessary for the computational simulation of hydrogen-enhanced Diesel combustion for premixed hydrogen charges ingested into the intake air and for direct injected hydrogen pilot charges into the cylinder. This includes a dual-fuel mechanism, a Lagrangian gaseous injection scheme, an improved spray particle breakup model, an advanced chemical kinetic reaction solver, as well as a complex n-heptane chemical kinetic reaction mechanism consisting of 35 species and 119 reversible reactions capable of describing both premixed and mixing controlled hydrogen/Diesel co-combustion at various fuel concentrations. The results showed that low levels of either hydrogen …

Extraction Of Pendulum Model Parameters From Steady-State Slosh Data With Adaptive Gradient Descending Optimization Method For Spacecraft Propellant Tanks, Tengjie Gao

Theses and Dissertations

This thesis proposes a new experimental approach to extract pendulum model parameters from spacecraft propellant tank slosh data. The novelty of the approach is in the utilization of steady-state triaxial force measurements at the support points of the tank under sinusoidal excitation, which enables repeatable and accurate determination of pendulum model parameters in contrast to the single-axis force sensing and multiple repetitions averaging techniques associated with the more common decay approach. This approach may be used for tanks with free slosh; however, this thesis considers a diagram tank with three different diaphragm configurations under translational oscillatory lateral excitation. With the …

Behavior Of Selective Oxygen Functional Groups Upon Hydrothermal Carbonization And Pyrolysis Of Biomass And Their Roles On Selective Applications, Nepu Saha

Theses and Dissertations

Hydrothermal carbonization (HTC) is a thermochemical process where biomass is treated in water under high temperature and corresponding vapor pressure. During HTC, biomass undergoes a series of reactions including hydrolysis, decarboxylation, dehydration, aromatization, and polymerization. As a result, a solid product is produced from biomass after HTC process, which is widely known as hydrochar. Depending on the HTC process conditions, a wide-variety of oxygen-containing groups formed on hydrochar surfaces. Many of these groups could play critical roles in applications such as adsorption, and energy and gas storage, etc. However, not all functional groups are exposed on the surface due to …

Bioink Optimization And Effects Of Microgravity On 3d Bioprinted Cell Laden Constructs, Likitha Somasekhar

Theses and Dissertations

Bioengineered 3D tissue constructs have gained attention as in vitro tools for the study of cell-cell and cell-matrix interactions and are being explored for potential use as experimental models for mimicking human tissues. One of the main problems in tissue engineering is the necessity to vascularize complex engineered tissues and sacrificial printing has been recognized as a possible solution to vascularization of the bioprinted tissues. Research studies have demonstrated that exposure to microgravity in space induces adaptive alterations in vascular structure and function. Changes in the morphology and gene expression is observed when endothelial cells are exposed to microgravity and …

A Comparative Study To Assess The Osteogenic Potential Of Competing Bioceramics For Bone Tissue Engineering, Nashaita Patrawalla

Theses and Dissertations

Biomimetic composite scaffolds comprising of bioactive ceramic-based materials incorporated within a polymeric framework have shown considerable promise for use in bone tissue engineering (BTE) applications. Although bioceramics have shown immense promise for use in BTE, few studies have performed a head-to-head comparison of the osteogenic properties of the most promising bioceramic materials. The goal of this study was to compare three different bioceramics – Bioglass 45S5 (BG), Laponite XLG (LAP), and β-Tricalcium Phosphate (TCP) – on the physical properties (i.e., swelling, stability, compressive modulus, bone bioactivity) of methacrylated collagen (CMA) hydrogels and osteogenic differentiation of human MSCs (hMSCs) encapsulated within …

Validation Of Arterial Distensibility Neural Network Model With Clinical Data, Cassondra Michelle Petersen

Theses and Dissertations

Cardiovascular diseases continue to plague the world as the number one killer of adults each year. As cardiovascular diseases can start with seemingly no symptoms, heart disease has been coined as the silent killer. With the ongoing COVID-19 global pandemic, the need for advances in cardiovascular advances has become even more prevalent as this virus is known to cause more severe damage to those who have underlying cardiovascular problems. These two reasons show the dire clinical need for researchers to continue to use novel techniques such as neural networks to find new approaches for helping physicians non-invasively and quickly add …

Over The Ocean Rf Propagation Modeling And System Design For Wireless Broadband Systems, Rayan Enaya

Theses and Dissertations

The research presented in this document considers the development of a terrestrial wireless communication system for providing connectivity to vessels within coastal waters. The system operates in the 2.4GHz ISM band and can provide throughputs that are on the order of 1-20Mbps. Several important aspects of the system design are considered. First, the propagation path loss in the2.4GHz band over the coastal water is characterized. The characterization is performed through an extensive measurement campaign. A practical propagation model is developed. Second, since 2.4GHz is an unlicensed spectrum, it hosts many other wireless systems. These systems create substantial noise in the …

Flagellation Testing Of Composite Finger Skirts For Surface Effect Ship (Ses) Application, Natalie Marie Holliday

Theses and Dissertations

The objective of this research is to create flagellation data for SES finger skirts. The SES design allows it to have a high tonnage with low draft, little drag, low wavemaking resistance, remarkable carrying capacity, and incredible propulsive efficiency. A SES is a sidehull hovercraft, with air cavity sealing components at the bow and stern. The fingers at the bow collectively make up an elastic, flexible full sealing skirt, dissipating oncoming waves and allowing for the vessel to be self-stabilizing. The problem with SES vessels is that the bow finger skirts wear significantly over a short period of time (~ …

The Effect Of Simulated Mangrove Forest Width On Shoreline Stabilization At Multiple Tidal Water Levels, James Edward Austin

Theses and Dissertations

Red mangrove (Rhizophora mangle) forests protect hundreds of miles of Florida’s shorelines from erosion and wave damage associated with severe storms and daily wave action. Shorelines are often protected from erosion with man-made structures such as seawalls, revetments, and breakwaters. However, these man-made structures disrupt natural ecosystems and cause scour and erosion in surrounding areas. The presence of mangroves not only prevents erosion but shelters marine life and filters water, promoting ecological health. Mangroves are now being implemented for wave energy reduction and shoreline stabilization, but there is little quantitative data about the precise sediment transport induced or prevented by …

A Deep Learning-Based Automatic Object Detection Method For Autonomous Driving Ships, Ojonoka Erika Atawodi

Master's Theses

An important feature of an Autonomous Surface Vehicles (ASV) is its capability of automatic object detection to avoid collisions, obstacles and navigate on their own.

Deep learning has made some significant headway in solving fundamental challenges associated with object detection and computer vision. With tremendous demand and advancement in the technologies associated with ASVs, a growing interest in applying deep learning techniques in handling challenges pertaining to autonomous ship driving has substantially increased over the years.

In this thesis, we study, design, and implement an object recognition framework that detects and recognizes objects found in the sea. We first curated …

Impact Of Antecedent Wetness And Rainfall Spatial Variability On Design Floods, Rachael Nicole Mcmahon

Theses and Dissertations

In the absence of long hydrologic records, water engineering design application rely primarily on the concept of design storms and subsequently design floods. However, despite the long-lasting use of these approaches there are several aspects that merit careful consideration and possibly revision. Representation of spatial variability of rainfall extremes in design storms has relied primarily on the use of area reduction factors that while useful, they do not represent realistic patterns of flood inducing storms. Furthermore, the impact of antecedent wetness on the transformation of design storms to design floods is often neglected. In this work we carry out a …

Editorial: Let's Talk About P(Ee), Brooke K. Mayer

Civil and Environmental Engineering Faculty Research and Publications

Practitioner points

• Phosphorus recycling and reuse are imperative, and the water industry has an important role to play in this effort.
• Technologies capable of removing phosphorus to ultra-low levels and subsequent recovery for phosphorus reuse are needed.
• Inorganic ion exchange resins and organic bioadsorbents are promising for phosphorus removal and recovery as part of the waste-to-resource paradigm.

Development Of A Laser-Assisted Chemical Vapor Deposition (Cvd) Technique To Grow Carbon-Based Materials, Abiodun Ademola Odusanya

Graduate Theses/Dissertations

Carbon-based materials (CBMs) including graphene, carbon nanotubes (CNT), highly ordered pyrolytic graphite (HOPG), and pyrolytic carbon (PyC) have gained so much attention in research in recent years because of their unique electronic, optical, thermal, and mechanical properties. CBMs are relatively very stable and have minimal environmental footprint. Various techniques such as mechanical exfoliation, pulsed laser deposition, and chemical vapor deposition (CVD) have been used to grow CBMs and among them thermal CVD is the most common. This study aims to explore ways of reducing the energy requirement to produce CBMs, and for that, a novel pulsed laser-assisted CVD technique had …

Heterogeneous Graph-Based User-Specific Review Helpfulness Prediction, Dongkai Chen

Dartmouth College Master’s Theses

With the popularity of e-commerce and review websites, it is becoming increasingly important to identify the helpfulness of reviews. However, existing works on predicting reviews’ helpfulness have three major issues: (i) the correlation between helpfulness and features from review text is not clear yet, although many standard features are proposed, (ii) the relations between users, reviews and products have not been considered, (iii) the effectiveness of the existing approaches have not been systematically compared. To address these challenges, we first analyze the correlation between standard features and review helpfulness that are widely used in other work. Based on this analysis, …

A Fully-Automated, Deep Learning-Based Framework For Ct-Based Localization, Segmentation, Verification And Planning Of Metastatic Vertebrae, Tucker Netherton, Tucker James Netherton

Dissertations and Theses (Open Access)

Palliative radiotherapy is an effective treatment for the palliation of symptoms caused by vertebral metastases. Visible evidence of disease is localized on medical images as part of the treatment planning process. However, complicating factors such as time pressures, anatomic variants in the spine, and similarities in adjacent vertebrae are associated with wrong level treatments of the spine. In addition, erroneous manual contouring of anatomic structures is a major failure mode in radiotherapy treatment planning.

The purpose of this study is to mitigate the challenges associated with treatment planning of the spine by automating the treatment planning process for three-dimensional conformal …

Development Of Quantitative Ultrasound-Mediated Molecular Imaging Of The Tumor Microenvironment, Trevor Mitcham

Dissertations and Theses (Open Access)

While conventional diagnostic imaging modalities provide anatomical information to clinicians, these techniques are not sensitive to critical physiological processes. In order to properly classify cancer, it is necessary to investigate noninvasive methods which can provide insight into these processes, allowing clinicians to determine personalized therapeutic options. Therefore, molecular imaging is focused on visualization and characterization of biomarkers within the tumor microenvironment (TME), which can then be combined with the anatomical information provided from diagnostic imaging.

Two such biomarkers of interest are blood oxygen saturation (SO₂) and cell receptor expression. SO₂ is a measure of the fraction of …

Cortical Dynamics Of Language, Kiefer Forseth

Dissertations and Theses (Open Access)

The human capability for fluent speech profoundly directs inter-personal communication and, by extension, self-expression. Language is lost in millions of people each year due to trauma, stroke, neurodegeneration, and neoplasms with devastating impact to social interaction and quality of life. The following investigations were designed to elucidate the neurobiological foundation of speech production, building towards a universal cognitive model of language in the brain. Understanding the dynamical mechanisms supporting cortical network behavior will significantly advance the understanding of how both focal and disconnection injuries yield neurological deficits, informing the development of therapeutic approaches.

Improving Treatment Of Local Liver Ablation Therapy With Deep Learning And Biomechanical Modeling, Brian Anderson, Kristy Brock, Laurence Court, Carlos Eduardo Cardenas, Erik Cressman, Ankit Patel

Dissertations and Theses (Open Access)

In the United States, colorectal cancer is the third most diagnosed cancer, and 60-70% of patients will develop liver metastasis. While surgical liver resection of metastasis is the standard of care for treatment with curative intent, it is only avai lable to about 20% of patients. For patients who are not surgical candidates, local percutaneous ablation therapy (PTA) has been shown to have a similar 5-year overall survival rate. However, PTA can be a challenging procedure, largely due to spatial uncertainties in the localization of the ablation probe, and in measuring the delivered ablation margin.

For this work, we hypothesized …

Development Of Biomaterials For Drug Delivery, Raquel De Castro

Graduate Theses and Dissertations

Drug delivery systems (DDS) have highly evolved in the last decades with the development of hydrogels and nanoparticles. However, high systemic uptake, side effects, low bioavailability, and encapsulation efficiency continue to be a major hurdle faced by such DDSs.

Nanoparticles and hydrogels can be specifically designed for targeted DDSs to mitigate some of the problems. This dissertation aimed to design two DDSs for ocular drug delivery and one for cancer treatment. The first project sought to develop chitosan nanoparticles (Cs-NP) using PEGDA as a copolymer to encapsulate gentamicin (GtS) for ocular drug delivery. Cs-NPs contain positive charges that can interact …

Exploration Of Antimicrobial And Cell Proliferation Properties Of Nanofibers Incorporating Nopal (O. Cochenillifera) Extract, Cristobal Rodriguez

Theses and Dissertations

This study focused on the fabrication of Forcespinning® nanofibers composed of Opuntia cochenillifera, ‘nopal’, mucilage (N) extract, chitosan (CH), and pullulan (PL) (N/CH/PL) were developed with an optimum fiber average diameter of 406±127 nm, and studied for their ability to sustain adhesion and proliferation of mouse embryonic fibroblast (NIH 3T3) cells. After a 6-day incubation period, N/CH/PL nanofibers displayed robust cell proliferation, while also exhibiting inhibitory properties through an N extract dip-coating process against gram-negative bacteria Escherichia coli in a 24 h bacterial growth study. A demonstration of integrated natural bioactive compounds with combined biodegradable polymers, provide an enhanced …

Automated Quality Control In Manufacturing Production Lines: A Robust Technique To Perform Product Quality Inspection, Mark Anthony Reyna

Theses and Dissertations

Quality control (QC) in manufacturing processes is critical to ensuring consumers receive products with proper functionality and reliability. Faulty products can lead to additional costs for the manufacturer and damage trust in a brand. A growing trend in QC is the use of machine vision (MV) systems because of their noncontact inspection, high repeatability, and efficiency. This thesis presents a robust MV system developed to perform comparative dimensional inspection on diversely shaped samples. Perimeter, area, rectangularity, and circularity are determined in the dimensional inspection algorithm for a base item and test items. A score determined with the four obtained parameter …

Analysis, Modeling, And Simulation (Ams) Case Studies Of Connected And Automated Vehicle (Cav) Implementations Specific To The South Central Region, Christopher Melson, Jiaqi Ma

Publications

Connected and automated vehicles (CAVs) offer potentially transformative and far-reaching impacts to the transportation system. However, realized benefits will be directly tied to how well agencies prepare for these technologies. This report documents efforts that support CAV preparatory actions in Louisiana and includes: (1) conducting a stakeholder survey to inform engagement activities to develop strategic partnerships in CAV deployment and (2) conducting crash analyses for deployment scenarios of CAV-based queue warning systems (QWSs).

An electronic survey was developed and disseminated to 273 Louisiana organizations. The purpose of the survey was to engage these organizations under the context of CAV planning …

Wearables And Wearable Data In Tele-Health Applications, Jack Mazza

Honors Theses

With the sudden emergence of Covid-19, Tele-Health has been forced into the forefront of healthcare. With no human contact, regular in-person doctor or clinic visits could not be made. Unfortunately, there is a gap in patient data for healthcare professionals when making diagnoses remotely. Fortunately, many users are constantly collecting some primary health data through wearables that have become commonplace in users' homes. Tapping into this unused data could provide healthcare professionals with a better picture of patients' health remotely. In this thesis, I will determine whether this wearable data can be a viable addition to Tele-Health applications, providing additional …

Improving The Efficacy Of Epinephrine Delivery For Anaphylaxis Through Development Of A Novel Auto-Injector Device And Increased User Education, Jennifer Ansley Myers

Honors Theses

Anaphylaxis is a life-threatening condition caused by the body’s overreaction to a certain allergen. The most widely accepted treatment for this condition is immediate administration of epinephrine, a hormone secreted by the adrenal glands that initiates the body’s fight or flight response, through an intramuscular injection. In most cases, patients that experience anaphylaxis are prescribed an epinephrine auto-injector to carry with them at all times which contains a single dose of epinephrine. Though these devices have been widely accepted for many years, there are many problems caused by their design and the lack of training that their users receive. The …

Aveva Competition 2021: Dimethyl Ether Production Process, Nicholas Gaouette

Honors Theses

The following study was conducted to assess the economic and process feasibility of a dimethyl ether (DME) production process. A portion of the methanol produced by an existing facility would be used to produce DME through a dehydration reaction. DME production is being considered as a means to compensate for lost methanol revenue, as methanol prices have recently decreased and an excess supply is present on the open market.

The first milestone in the study was the construction of a working process model within AVEVA Process Simulation. This steady-state process model would provide information essential to further design and optimization …

Feasibility Study Of Portable Solar Powered Blood Storing Refrigerator, Saroj Subedi

Honors Theses

This report is focused on the preliminary feasibility of portable solar-powered blood-storing refrigerators primarily based on calculations of energy required to maintain the temperature of the refrigerator, the electricity required throughout the day, calculating sufficiency of power supplied by the solar panel, and selection of battery for power storage. The method and the trend of a feasibility study involve the study of blood properties, separation of blood components after donation, and their storage conditions. Then, the portable size of the refrigeration has been proposed with three different compartments for storage of each blood component. The further methods involve the selection …

An Open-Baffle Motional Feedback Loudspeaker, Matthew Quinlivan, William Harvie

Honors Theses

A dynamic loudspeaker mounted in an open baffle has the same parameters as a loudspeaker in free space. A subwoofer mounted in an open baffle has a small total quality factor and therefore the frequency above which the driver has a significant output is too high despite the subwoofer's low resonant frequency. To address this issue, we implemented a motional feedback circuit with the goal of introducing both velocity feedback and acceleration feedback into the loudspeaker system and thus altering the resonant frequency and total quality factor of the system. After verifying the efficacy of our feedback circuit with computer …

Design And Analysis Of A Process To Convert Methanol Into Dimethyl Ether, Elisa M. White

Honors Theses

A recent economic downturn led to the loss of a contract for a company that sells methanol. The company has two options to recover some of the profit lost from the contract termination. One option is to sell the excess methanol at the spot market price, and the second option is to implement a process to convert the excess methanol into dimethyl ether. This project investigated the implementation of a process to convert the methanol from the lost contract into dimethyl ether. The process was simulated in AVEVA Process Simulation to estimate the size of equipment needed. A toller provided …

A Golden Age For Computing Frontiers, A Dark Age For Computing Education?, Christof Teuscher

Electrical and Computer Engineering Faculty Publications and Presentations

There is no doubt that the body of knowledge spanned by the computing disciplines has gone through an unprecedented expansion, both in depth and breadth, over the last century. In this position paper, we argue that this expansion has led to a crisis in computing education: quite literally the vast majority of the topics of interest of this conference are not taught at the undergraduate level and most graduate courses will only scratch the surface of a few selected topics. But alas, industry is increasingly expecting students to be familiar with emerging topics, such as neuromorphic, probabilistic, and quantum computing, …