Engineering Commons^™

Scale-Up And Measurement Enhancements Of A Biogenerator Bioreactor, Jason J. Glas

Electronic Thesis and Dissertation Repository

Renewable energies in the form of wind and solar have seen steadfast growth across the world, however the abundance of these technologies that demonstrate short-term variability in power output threatens power grid stability and necessitates the use of fossil fuels for rapid throttling capability. A requirement for large scale energy storage systems becomes necessary and a system based on hydrogen generation, storage, and consumption for electrical grid supply-demand stabilization using a ferric sulfate oxidant is herein explored, named the BioGenerator. As the name implies, the system functions as an indirect microbial fuel cell using a biologically active broth dominated by …

Breast Cancer Risk In Women With Breast Bilateral Asymmetry: Machine Learning Based Risk Analysis And Mitigation Through Developing A Framework For Customized Bra Design, Xi Feng

Electronic Thesis and Dissertation Repository

Breast cancer is the most prevalent form of cancer globally, accounting for 12.5% of all new cases annually. Research has found a significant correlation between breast bilateral asymmetry and an increased risk of cancer, with women diagnosed with breast cancer having higher levels of bilateral asymmetrical breast volume. Unfortunately, 87% of women with breast asymmetry lack adequate tools for assessing their cancer risk. Early screening using bilateral asymmetry to predict a woman's long-term risk of breast cancer can help physicians make informed decisions about whether to recommend sequential imaging and the frequency of screening. Another important factor in understanding the …

Investigation Of Segregation In Mixing Pharmaceutical Powders Using Passive Acoustic Emissions In A V-Blender, Omar Salem

Electronic Thesis and Dissertation Repository

Powder mixing is a crucial and complex step in pharmaceutical production. Monitoring of mixing and segregation processes can be achieved using process analytical technologies to improve product quality. Passive acoustic emissions were examined during mixing in a V-blender. Vibrations from the emissions were measured through an accelerometer affixed to the outer V-shell arm lid. Horizontal and vertical loading configurations of particles were examined. Stable mixtures were reached when the measured amplitude plateaued around the approximate weighted average of the particles in the outer V-shell arm. Horizontal loading trials mixed faster and reached stable mixtures in fewer revolutions than vertical loading …

Machine Learning Classifiers For Chronic Obstructive Pulmonary Disease Assessment Using Lung Ct Data., Halimah Alsurayhi

Electronic Thesis and Dissertation Repository

Chronic Obstructive Pulmonary Disease (COPD) is a condition characterized by persistent inflammation and airflow blockages in the lungs, contributing to a significant number of deaths globally each year. To guide tailored treatment strategies and mitigate future risks, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) employs a multifaceted assessment system of COPD severity, considering patient's lung function, symptoms, and exacerbation history. COPD staging systems, such as the high-resolution eight-stage COPD system and the GOLD 2023 three staging systems, have been later developed based on these factors. Lung Computed Tomography (CT) is becoming increasingly crucial in investigating COPD as it …

Physical And Geometrical Modulation Of Human Fibroblast Behaviour, Sarah M. Brooks

Electronic Thesis and Dissertation Repository

This thesis investigates the impact of mechanical stimuli, specifically substratum topography and elastic modulus, on dermal and gingival fibroblast behaviour associated with scarring and regeneration. Scar formation presents a significant issue for implanted biomaterials often leading to device failure. Even though scar formation is a normal end point to adult human dermal wound healing, gingival wounds are capable of tissue regeneration or scarless wound healing. Understanding how these cells respond to environmental cues, including substratum topography and elastic modulus, is central to the development of novel biomaterials for stimulation of tissue regeneration. It was hypothesized that topographic features, with submicron …

Numerical Study Of Ozone Decomposition Reaction Behaviours In Gas-Solids Circulating Fluidized Bed Reactors, Zhengyuan Deng

Electronic Thesis and Dissertation Repository

This study numerically investigated the reaction behaviours of catalytic ozone decomposition reaction in a 10.2-meter-tall gas-solids circulating fluidized bed (CFB) reactor. A pseudo-homogeneous reactive transport model for ozone decomposition, integrated with the two-fluid model, was developed and validated using experimental data. Based on the model, the impacts of turbulence models, specularity coefficients, and simulation methods on reaction behaviours in the CFB riser reactor were explored. These three factors were found to significantly affect the hydrodynamic characteristics and the reaction behaviours in the riser. A comparative study of CFB riser and downer reactors was conducted. Operations in the direction of and …

Bioactive And Electrically Conductive Nanocomposite Bone Biomaterials, Rebeca A. Arambula-Maldonado

Electronic Thesis and Dissertation Repository

Electrically conductive carbon-based materials are emerging as potential biomaterials for bone tissue engineering. Their incorporation into organic-inorganic nanocomposites mimics the structural composition and electrically conductive nature of bone.

The aim of this research was to design bone biomaterials from gelatin-based polymers, tertiary bioactive glasses (BG) via a sol-gel method, and multiwall carbon nanotubes (MWCNT). The incorporation of calcium into organic-inorganic nanocomposites plays an essential role in the development of bioactive bone biomaterials. Calcium chloride and calcium ethoxide were investigated as calcium sources in gelatin-BG-MWCNT nanocomposites. The resulting surface elemental distribution was homogeneous, but the swelling, degradation and porosity properties of …

Value Of Service-Oriented Multi-Service Provisioning And Resource Allocation In Integrated Localization, Sensing And Communication Systems, Biwei Li

Electronic Thesis and Dissertation Repository

The unprecedented proliferation of wireless infrastructures and their ongoing convergence with diverse industrial Internet of Things (IoT) applications introduce new demands for upcoming wireless networks. In response to such diversity of demands, envisioned future wireless networks must have multiple beyond communication capabilities, such as localization and sensing. To efficiently utilize, allocate, and manage these capabilities, the integration of localization, sensing, and communication (ILSAC) within a unified wireless system structure is of utmost importance. However, the seamless integration of ILSAC into intricate network infrastructures is encumbered by critical challenges, including high-accuracy localization/sensing algorithm, efficient resource management and allocation scheme, and robust …

The Development And Testing Of A Gyroscope-Based Neck Strengthening Rehabilitation Device, Nicole D. Devos

Electronic Thesis and Dissertation Repository

Neck pain can be debilitating, and is experienced by the majority of people at some point over the course of their life. Resistance training has been shown to have significant improvement in pain or disability for patients. There are few options available for telerehabilitation, and the use of gyroscope stabilizers is proposed for this use. A biomechanics model of a head--neck--gyroscope system was created. In order to also model the dynamics of such a system, this work proposes a blended method using the Denavit--Hartenberg (DH) convention, popular in the field of robotics, with the Lagrangian mechanics approach to analyze an …

Attribution Robustness Of Neural Networks, Sunanda Gamage

Electronic Thesis and Dissertation Repository

While deep neural networks have demonstrated excellent learning capabilities, explainability of model predictions remains a challenge due to their black box nature. Attributions or feature significance methods are tools for explaining model predictions, facilitating model debugging, human-machine collaborative decision making, and establishing trust and compliance in critical applications. Recent work has shown that attributions of neural networks can be distorted by imperceptible adversarial input perturbations, which makes attributions unreliable as an explainability method. This thesis addresses the research problem of attribution robustness of neural networks and introduces novel techniques that enable robust training at scale.

Firstly, a novel generic framework …

Modeling Thermosyphon And Heat Pipe Performance For Mold Cooling Applications, Dwaipayan Sarkar

Electronic Thesis and Dissertation Repository

Thermosyphons are enhanced heat transfer devices that can continuously transfer very large amounts of heat rapidly over long distances with small temperature differences. The high heat transfer rate is achieved through simultaneous boiling and condensation of the working fluid and the continuous heat transfer is achieved through recirculation of the working fluid in its liquid and vapor phase. A potentially important application of the thermosyphons has been towards reducing the cycle times of the mold cooling processes which would provide economic incentives to the automotive industry.

Different operational and geometrical parameters such as the input heating power, fill ratio (FR), …

Analyses For Assessing The Centreline Translation, Asymmetrical Wind-Field, And Velocity Fluctuations Of Tornado Vortices, Niall C. Bannigan

Electronic Thesis and Dissertation Repository

Tornadoes present an ever-increasing threat to communities worldwide, especially those with geographic conditions that place them in the path of several tornadoes annually. These conditions are likely to be exacerbated by ongoing trends in the climate. As such, it is necessary to move towards experimental and numerical tornado-like vortex studies that allow for more advanced simulation methods. Novel techniques for tracking and analysing tornado vortices simulated at high spatial and temporal resolution are presented herein. Significant wandering of the tornado's position and large peaks in the velocity field can be captured, demonstrating tangential gusting at more than 1.5 times the …

Design Of Active Pharmaceutical Ingredients Solid States In Crystallization Processes, Weizhong Gong

Electronic Thesis and Dissertation Repository

Crystallization is an important technique to obtain solid-state drugs from solutions. Physicochemical properties of the active pharmaceutical ingredients (APIs) are determined by crystallization. More than half of the active pharmaceutical ingredients exhibit polymorphism, the phenomenon of chemical species showing more than one unit-cell structure in the solid state. Controlling polymorphism is one of the most important goals during pharmaceutical manufacturing. Nevertheless, the control of polymorphism is sometimes not enough to realize the targeted physicochemical properties. Suitable additives (coformers/salt formers) are explored to generate new multi-component solid phases of poorly soluble/bioavailable active pharmaceutical ingredients (APIs). The design of pharmaceutical cocrystals and …

The Effect Of Steam Explosion On Lipids Extraction From Microalgae And Derivation Of Pectin Films From Waste Culture, Shahil Chhiba

Electronic Thesis and Dissertation Repository

The objective of this study was to investigate the properties of sustainable replacements for plastics and diesel fuel, derived from microalgae (Chlorella vulgaris) subjected to steam explosion. During the process, oven temperatures of up to 500 °C were reached, with the experiments left for different times after reaching their maximum internal temperature. Lipids were extracted from algal cultures using a modified Folch method. The waste microalgae were combined with pectin and glycerol to form biodegradable films, and their solubilities and tensile strengths were measured. The highest yield was 124 mg lipids/g microalgae from 400 °C steam explosion for …

Towards Patient Specific Mitral Valve Modelling Via Dynamic 3d Transesophageal Echocardiography, Patrick Carnahan

Electronic Thesis and Dissertation Repository

Mitral valve disease is a common pathologic problem occurring increasingly in an aging population, and many patients suffering from mitral valve disease require surgical intervention. Planning an interventional approach from diagnostic imaging alone remains a significant clinical challenge. Transesophageal echocardiography (TEE) is the primary imaging modality used diagnostically, it has limitations in image quality and field-of-view. Recently, developments have been made towards modelling patient-specific deformable mitral valves from TEE imaging, however, a major barrier to producing accurate valve models is the need to derive the leaflet geometry through segmentation of diagnostic TEE imaging. This work explores the development of volume …

Investigation Of Thermofluid Processes In A Pcm Based Thermal Storage Module, Luca M. Crnjac

Electronic Thesis and Dissertation Repository

Latent heat thermal energy storage systems can capture and store solar thermal energy, enhancing the reliability of solar energy by facilitating a continuous and consistent energy supply. However, phase change materials used in these systems suffer from low thermal conductivities making it difficult to achieve suitable charging and discharging rates. The present research investigated this issue using computational and experimental approaches to improve the design of a thermal storage module through heat transfer enhancement. Various heat transfer enhancements including a finned honeycomb structure, and metal wool were incorporated into a thermal storage module to analyze their effect on charging and …

Analysis And Characterization Of Embroidered Textile Strain Sensors For Use In Wearable Mechatronic Devices, Jose Guillermo Colli Alfaro

Electronic Thesis and Dissertation Repository

Stroke and musculoskeletal disorders affect hundreds of millions of people around the world. To aid in the recovery process of people affected by these conditions, the use of wearable mechatronic devices has been proposed during traditional rehabilitation therapies. However, factor such as rigidity, increased weight, and overall bulkiness have hindered the adoption of these devices in a clinical setting. Therefore, alternative solutions in the form of soft wearable mechatronic devices have been proposed recently. This is due to these devices being lightweight and comfortable, and compliant, which makes them easier to conform to the human body. To achieve such compliance, …

Temperature-Controlled Partial Nitrification For Mainstream Wastewater Deammonification Using Batch, Semi-Batch And Continuous Systems, Niema Afroze

Electronic Thesis and Dissertation Repository

Aeration is a critical component of the two-step nitrification, the biological conversion of ammonia (NH₃) to nitrite (NO₂-) and then to nitrate (NO₃-), in municipal wastewater treatment plants. Aeration provides the necessary dissolved oxygen for the growth and activity of nitrifying bacteria to Partial nitrification-Anammox (PN-Anammox) is a two-step biological wastewater treatment process, used to remove nitrogen compounds from wastewater efficiently without the need for external carbon. It combines partial nitrification, where ammonia is partially oxidized to nitrite, with anaerobic ammonium oxidation (Anammox) to remove both ammonia and nitrite. About a 60% to 80% …

Characterizing Tkr Biomechanics Using A Novel Muscle-Driven Joint Motion Simulator, Alexandre Galley

Electronic Thesis and Dissertation Repository

Total knee replacement (TKR) is the end-stage treatment for severe cases of knee osteoarthritis (OA). Despite its success in alleviating pain and restoring mobility to the knee, patient satisfaction rates post-TKR are still lower than other common joint replacement surgeries. Knee kinematics and stability, key determinants of successful TKR, are assessed intraoperatively and tracked post-operatively in in vivo clinical studies. However, the persistently low satisfaction rates suggest that more sophisticated pre-clinical testing methods are needed to better understand the biomechanics of these implants early in their development. During pre-clinical testing of TKR implants, different joint motion simulators are used for …

Multi-Dimensional Qos And Collaborative Mac Layer Design For Dense, Diverse, And Dynamic Iot Network, Jiyang Bai

Electronic Thesis and Dissertation Repository

With the ubiquitous proliferation of Internet of Thing (IoT) devices, Access Points (APs) of future Wireless Fidelity (Wi-Fi) networks are expected to support dense Stations (STAs) with diverse Quality-of-Service (QoS) requirements under dynamic channel conditions. On account of high access collision and optimization problem complexity, the performance degradation brings new challenges to the existing Media Access Control (MAC) layer design in Wi-Fi. This thesis proposes novel technologies to enable low-latency high-performance MAC layer designs, which support dense access of STAs with real-time solutions of resource allocation and link adaptation problems. Both grouping and collaborative architectures are utilized based on game …

Study Of Multi-Dimensional Transfer Effects In Applied Smouldering Systems, Seyed Ziaedin Miry Mr

Electronic Thesis and Dissertation Repository

Smouldering is a flameless form of combustion that is driven by oxygen directly diffusing into the surface of condensed phase fuel (liquid or solid) and involves a complex interplay between heat and mass transfer through porous media, chemical reactions, and multiphase flow. Applied smouldering systems have been gaining popularity for a variety of applications including (i) energy and resource recovery, (ii) waste-to-energy, (iii) pyrolysis and gasification, and (iv) applied smouldering of organic liquids/solids for environmental benefits. In all contexts, smouldering is a complicated oxygen-limited phenomenon where multi-dimensional transfer effects (i.e., non-uniformities in …

Understanding Real-World And Laboratory Traumatic Brain Injury (Tbi) Using The Computational Model With Brain Functional Regions, Kewei Bian

Electronic Thesis and Dissertation Repository

Traumatic brain injury (TBI), including mild traumatic brain injury (mTBI) or concussion, is a severe health concern. Many symptoms, such as headache, dizziness, and working memory deficits, are reported to be related to the dysfunction of brain functional regions, but the underlying mechanism remains unknown. Hence, further developing tools and analyses to understand brain dysfunction for better TBI prevention are important. Additionally, such analyses should be conducted for both real-world TBI cases and laboratory studies, as TBI data can only be collected from the real world, and prevention measures, such as helmets, are developed and evaluated in the lab. Accordingly, …

Performance Recovery Of Scale Reduced Cyclone Particle Separators Using A Rotating Classifier, Mark J. Parker

Electronic Thesis and Dissertation Repository

Cyclone particle separators are often used to collect particles that are of value or environmental concern. These devices achieve high Total Collection Efficiency (TCE) with steady pressure drop. Increasing the height of the cyclone improves both TCE and pressure drop. However, due to the height of the cyclone, these devices are often forced to be placed outside, which can lead to decreased performance over time. The research examines the outcome of scale reducing a cyclone. This is achieved by (i) how the scale reduction changes the flow field, (ii) identifying what flow aspects contribute to the reduction in TCE and …

An Investigation Into Computational Modelling Of Melting And Solidification Of Phase Change Materials, Maryam Hemmat

Electronic Thesis and Dissertation Repository

This thesis evaluates the effectiveness of the enthalpy-porosity approach in simulating melting and solidification of phase change materials within latent heat thermal energy storage systems. It systematically investigates the sensitivity of the computational model to four adjustable parameters: mushy zone coefficient, thermal expansion coefficient, solidus/liquidus temperatures, and latent heat. The study includes individual and combined analyses of these factors in simulations of the melting process by comparing outcomes with extensive experimental data, resulting in a calibrated melting model. The calibrated model is validated across various heating conditions in the cylindrical cavity, and then in a rectangular cavity, confirming its reliability …

Patterned Heating Induced Propulsion, Saajid A. Aman

Electronic Thesis and Dissertation Repository

This study explores propulsion effects generated by patterned heating acting on smooth and corrugated surfaces. The model problem assumes that the upper plate moves freely, and the lower plate is stationary, equipped with grooves, and exposed to spatially distributed heating. Our findings identify two distinct propulsion effects: thermal streaming and thermal drift. Thermal streaming occurs when given sufficient heating intensity with net flow in the left or right direction characterized by a pitchfork bifurcation. The efficiency of this technique can be controlled using the wavelength of heating. Thermal drift represents a pattern interaction effect. Its strength depends on the relative …

Investigation Of Foam Based Photobioreactor For The Cultivation Of Chlorella Vulgaris Cpcc 90, Anuradha Krishnan

Electronic Thesis and Dissertation Repository

Today, microalgae are cultured in large-scale systems such as open ponds and photobioreactors. Open pond systems, while not expensive, have disadvantages, including contamination and high water consumption, resulting in increased cost of harvesting and quick evaporation. Photobioreactors overcome some of the challenges of an open pond system. However, the reactor setup, operation, and microalgae harvesting are relatively more expensive when compared to conventional techniques. In this study, a novel foam-based photobioreactor system was applied to investigate both the cultivation and harvest of microalgae using different surfactant agents, i.e., rhamnolipids, Bovine Serum Albumin (BSA), saponin, and the commercial surfactant Pluronic f127 …

Head Impact Effects In Small Remotely Piloted Aircraft System (Srpas) Collisions: Gender Specific Risks And Vulnerable Population Protection, Md Farhan Hoque Sagar

Electronic Thesis and Dissertation Repository

This study focuses on supporting the development of safety regulations for vulnerable populations during drone to head impacts. First, the small female head and neck model was compared to cadaveric data. Then, combined with lab’s previous work, gender-based disparities in head impact responses were highlighted, with small females experiencing higher injury risk metrics, despite lower skull von Mises stress. Beyond small females, children of various ages and their head responses during impacts were also analyzed. In addition to the previously developed quadcopter drone model, a new Mavic Pro drone model was developed, and this model was integrated with human head …

Experimental And Simulation Study Of Reactive Silver Ink Droplet Evaporation, Weipeng Zhang

Electronic Thesis and Dissertation Repository

The evaporation of particle-free silver ink droplets on heated substrates directly impacts the morphology of the resultant silver particles and films. In this thesis, COMSOL Multiphysics simulations of the solvent (water-ethylene glycol mixture) droplet evaporation process are used to explain the microflows, mass transfers, and heat distribution responsible for the experimental observations. The reactive ink incorporates fluoro-surfactant FS-31 and poly (acrylamide) (PAM) to suppress the coffee-ring effect that negatively impacts the electrical conductivity. Experiments show that the droplet evaporation process results in varied silver particle morphology, depending on the locations within the droplet, leading to uneven surfaces. Large particles (3 …

Free-Hand Photoacoustic Imaging Of Breast Cancer Tissue, Elina Rascevska

Electronic Thesis and Dissertation Repository

Approximately 19% of breast cancer patients undergoing breast conserving surgery (BCS) must return for a re-excision surgery due to positive margin reported by pathology. This problem is mainly associated with lack of intraoperative cancer margin assessment tools. Our previous work demonstrated that lipid-weighted photoacoustic imaging (PAI) can be used intraoperatively to successfully differentiate between cancerous and healthy tissue with high sensitivity. However, the technology was cumbersome and significantly prolonged the procedure time. The goal of this work was to develop a compact hand-held probe, working on lipid-weighted PAI principles, that can provide feedback during BSC without significantly altering the surgical …

Impinging Jet Flow And Hydraulic Jump Of Newtonian And Viscoplastic Liquids, Wenxi Wang

Electronic Thesis and Dissertation Repository

The steady laminar incompressible flow of an axisymmetric impinging jet of either a Newtonian fluid or a viscoplastic fluid of the Heschel-Bulkley type and the hydraulic jump of either a circular or polygonal shape on a solid disk is analyzed. The polygonal jump is induced by azimuthal dependence edge conditions: a non-circular disk or a circular disk with a variable edge film thickness. The thin-film and Kármán–Pohlhausen approaches are utilized as theoretical tools.

To cross the jump smoothly, a composite mean-field thin-film approach is proposed. The stress singularity for a film freely draining at the disk edge is found to …