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 …