Engineering Commons^™

Characterization And Control Of A Woven Biomimetic Actuator For Wearable Neurorehabilitative Devices, Vaughan K. Murphy

Electronic Thesis and Dissertation Repository

Strokes are a major cause of death and disability, with nearly 300,000 Canadians suffering from stroke-related disability. Many survivors suffer from upper limb paresis, which makes ordinary tasks difficult. Availability of care is an issue, with only 43.3% of patients in Ontario receiving proper treatment. Robot-assisted neurorehabilitation has been used to address limited clinician availability, and has been shown to improve patient strength and range of motion faster than or comparable to traditional methods. However, the size and weight of current devices limit their use to within therapists’ offices. Incorporating actuators into clothing would make the devices more comfortable, natural …

Simulation Of Operational Extreme Wind Conditions For Horizontal Axis Wind Turbines Based On Iec Standard, Kamran Shirzadeh Ajirlo

Electronic Thesis and Dissertation Repository

The possibility of simulating deterministic extreme operational conditions for horizontal axis wind turbines based on the IEC 61400-1 standard in the WindEEE Dome at Western University was investigated. WindEEE has 60 fans (a matrix of 4 by 15 with 0.8m diameter each) on one of the walls to generate straight and sheared flows. These fans were controlled by their power set-points and by their adjustable Inlet Guiding Vanes (IGV) to generate the Extreme Operational Gust (EOG), positive and negative Extreme Vertical Shear (EVS), and Extreme Horizontal Shear (EHS) cases as per IEC 61400-1 standard to be further applied for testing …

Joint Wind And Ice Effects On Transmission Lines In Mountainous Terrain, Daniel Davalos Arriaga

Electronic Thesis and Dissertation Repository

Atmospheric icing on mountainous terrain can produce catastrophic damages to transmission lines when incoming particles impinge and accrete on the cable surface of the system. The first challenge in wind-ice loading is determining joint statistics of wind and ice accretion on transmission lines. This study analyzes the weather characteristics for a specific site of study using 15 years of historical data to use as inputs for ice accretion modeling. The joint wind and ice hazard is characterized by simulating 500 years of icing events from the fitted probability distributions of ice accretion and wind on ice velocities. The second challenge …

Numerical Study Of The Effect Of Gas Distributors And Baffles On The Bubble Distribution, Gas And Solid Mixing In A Fluidized Bed, Xuelian Xing

Electronic Thesis and Dissertation Repository

In this study, the multi-phase Eulerian-Eulerian two-fluid method (TFM) coupled with the kinetic theory of granular flow (KTFG) was used to investigate hydrodynamics of particle flows (Geldart Group B) in a lab-scale fluidized bed Geldart Group B particles, operating in bubbling and turbulent regimes. The effect of gas distributors and baffles on the distribution of the gas bubbles, and the mixing of gas and solids were investigated under various superficial gas velocities.

The numerical model is validated by experimental results from two different measurement methods with various gas distributor configurations and a superficial gas velocity ranging from 0.4 m/s to …

Deep Reinforcement Learning In Medical Object Detection And Segmentation, Dong Zhang

Electronic Thesis and Dissertation Repository

Medical object detection and segmentation are crucial pre-processing steps in the clinical workflow for diagnosis and therapy planning. Although deep learning methods have achieved considerable performance in this field, they impose several shortcomings, such as computational limitations, sub-optimal parameter optimization, and weak generalization. Deep reinforcement learning as the newest artificial intelligence algorithm has great potential to address the limitation of traditional deep learning methods, as well as obtaining accurate detection and segmentation results. Deep reinforcement learning has a cognitive-like process to propose the area of desirable objects, thereby facilitating accurate object detection and segmentation. In this thesis, we deploy deep …

Effect Of The C-Source And Cod/N On Nitrite And Partial Nitrate Denitrification, Ahmed Fathy Elyas Badia

Electronic Thesis and Dissertation Repository

The main objectives of this study were: (i) to investigate dynamic specific denitrification rates (SDNR) from nitrite at various chemical oxygen demand (COD) / nitrogen (N) ratios using municipal wastewater (MWW) and acetate, and to study the kinetic parameters, (ii) to investigate the dynamic specific denitrification rates (SDNRs) from nitrite at various COD/N ratios in a system that uses methanol as a complementary carbon source, and studying the effect in case if nitrate replaced nitrite, and (iii) to investigate and compare between the nitrite shunt and N-PDN-anammox technologies through studying the dynamic specific denitrification rates (SDNRs) from nitrate and nitrite …

The Effect Of Joint Alignment After A Wrist Injury On Joint Mechanics And Osteoarthritis Development, Puneet Kaur Ranota

Electronic Thesis and Dissertation Repository

Wrist injuries are common and can lead to the development of post-traumatic osteoarthritis. For example, one major complication after a wrist fracture, is when the fractured bone heals in a mal-aligned position, called malunion. It has been assumed that a malunion after wrist fractures alters joint congruency and mechanics leading to the development of post-traumatic osteoarthritis and poor functional outcomes. It is unclear whether anatomical restoration is a key component for the management of wrist injuries and to limit the progression of post-traumatic osteoarthritis. However, the mechanistic pathways between joint structure (and mal-alignment) and patient outcomes, such as the development …

Development Of Water-Soluble Polyesters For Tissue Engineering Applications, Trent Gordon

Electronic Thesis and Dissertation Repository

The development of tunable polymers has become increasingly important for both tissue engineering and drug delivery. This thesis investigates the development of water-soluble polyesters that contain both natural and synthetic components. These polymers offer tunable chemical structures, as well as functional groups for the conjugation of crosslinking moieties or cell signaling molecules. The first series of polymers was synthesized from poly(ethylene glycol) (PEG) and aspartic acid (Asp) via a titanium catalyzed transesterification method to provide polymers with molar masses of 12 kg/mol. After deprotection, the pendent functional groups of Asp were reacted with methacrylic, maleic, and itaconic anhydride to introduce …

Chemically Enhanced Primary Treatment: Modelling And Resources Recovery, Wenjuan Mu

Electronic Thesis and Dissertation Repository

The chemically enhanced primary treatment (CEPT) process is gaining momentum for carbon redirection, thereby lowering the downstream liquid train load and maximizing energy recovery from the primary sludge. CEPT technique enhances coagulation and flocculation, that enable faster settling of particulate and colloidal solids and dissolved ions such as phosphate to enhance removal efficiency. Comprehending the dynamic behaviour of CEPT clarifiers is critical to not only develop a reliable whole plant simulation but also fully understand the efficacy of the treatment plant performance. To achieve such purposes, a great amount of efforts has been contributed to the advancement of primary clarifier …

Development And Validation Of Augmented Reality Training Simulator For Ultrasound Guided Percutaneous Renal Access, Yanyu Mu

Electronic Thesis and Dissertation Repository

Percutaneous renal access (PCA) is a critical step in needle-based renal procedures. Traditional PCA training relies on apprenticeship, which raises concerns about patient safety and limits training opportunities. In this thesis, we reviewed simulation-based training for PCA, described the development of a novel augmented reality (AR) simulator for ultrasound (US)-guided PCA, and evaluated its validity and efficacy as a teaching tool.

Our AR simulator allows the user to practice PCA on a silicone phantom using a tracked needle and US probe emulator under the guidance of simulated US on a tablet screen. 6 Expert and 24 novice participants were recruited …

Navigation And Patient Specific Instrumentation In Shoulder Arthroplasty, Joseph Cavanagh

Electronic Thesis and Dissertation Repository

The humeral head osteotomy influences shoulder arthroplasty component height, version and neck shaft angle and therefore outcomes. The purpose of this study is to develop and utilize navigation to execute the osteotomy.

3D printed models were used to develop a navigation technique, and then to execute planned osteotomies. Free hand, fixed angle guide, patient specific guides, and real time navigation osteotomies were completed. The height, neck shaft angle and version were recorded. Also collected, were the planes of the guides once they were placed.

Navigation had significantly less error from the planned osteotomy in neck shaft angle versus all other …

Characterization For Spray Droplet Behaviour In Afterburner-Like Flow Conditions, Matthew D. Mahaffy

Electronic Thesis and Dissertation Repository

Fuel injection processes can contribute to combustion instability in highly energetic combustion systems. In gas turbine engine afterburners, jet-in-crossflow (JIX) injection is used. Part one of the thesis study investigates the interaction between spray droplets and turbulent flow properties of a JIX. Jet-in-counterflow (JIC) configuration was also investigated. Part two of the investigation examined the behaviour of JIX droplets around a bluff body. Droplet size and flow turbulence was characterized simultaneously using particle image velocimetry and image processing techniques. Turbulence and droplet size were correlated, particularly at momentum flux ratios ≥ 60. High speed imaging was used to identify droplet …

Evaluation Of Warpage For Composite Automotive Components, Eric J. Martin

Electronic Thesis and Dissertation Repository

Thermoplastic composite parts are manufactured using compression molding for the purposes of assembly in a car seat sub-assembly. Concerns about the dimensional accuracy of the parts prompted an investigation into the part warpage. The warpage of the parts needs to be evaluated for the purposes of determining processing conditions which are linked to part warpage, in order to reduce part warpage.

Laser line probes (LLP) are becoming a more attractive tool for the purposes of part inspection. LLPs quickly acquire point cloud data from complex surfaces and are a non-contact method of measurement; these qualities make LLPs the best tool …

Lanthanide Nanoparticles As Contrast Agents For In Vivo Dual Energy Microcomputed Tomography Of The Mouse Vasculature, Charmainne Cruje

Electronic Thesis and Dissertation Repository

Dual energy (DE) computed tomography (CT) has the capability to influence medicine and pre-clinical research by providing quantitative information that can detect nascent lesions, identify perfusion restoration or inhomogeneities within tissues, and recognize the presence of calcium deposits. A wide variety of instrumentation techniques and scan protocols have been developed for DE CT, with a common goal of acquiring a pair of images that reports the attenuation of a given volume to two different x-ray distributions. While DE image acquisition has benefitted from technical advancements in CT, the contrast agents that are used are still predominantly composed of iodinated small …

Analytical And Computational Modelling Of The Ranque-Hilsch Vortex Tube, Nolan J. Dyck

Electronic Thesis and Dissertation Repository

The Ranque-Hilsch vortex tube (RHVT) is a simple mechanical device with no moving parts capable of separating a supply of compressed fluid into hot and cold streams through a process called temperature separation. The overall aim is to develop models which can be used to assess the temperature separation mechanisms in the RHVT, leading to a better overall understanding of the underlying physics. The introductory chapter contains a thermodynamic analysis and introduction to the flow physics, alongside three miniature literature reviews and critiques identifying research gaps.

The body of the thesis contains three articles. The first article studies the flow …

Cfd Simulations Of Bubble Column Equipped With Bundles Of Concentric Tubes, Glen C. Dsouza

Electronic Thesis and Dissertation Repository

Bubble column reactors are multiphase contactors that have found several industrial applications owing to various attractive features including excellent thermal management, low maintenance cost due to simple construction and absence of moving parts. In order to attain desired performance for a given application, these reactors are usually equipped with internals such as vertical tube bundles to facilitate heat transfer. The column hydrodynamics and turbulence parameters are altered when the column is occluded with internals which adds to the complexity of the problem. The use of Computational Fluid Dynamics (CFD) tools for the study of multiphase flows has gained a lot …

Performance Of A Drinking Water Treatment System For A Small Community In Rural Ghana, West Africa, Xiya Xu

Electronic Thesis and Dissertation Repository

In many African countries, the shortage of water resources is a common phenomenon. Providing safe and adequate water is an issue that must be considered by community leaders and municipal authorities. The present project investigated the performance of a small drinking water treatment system in a small community at Enyan Abaasa, Central Region, Ghana, through sampling and laboratory testing. The treatment system, which is fed by a deep borehole, consists sequentially of polypropylene (PP) yarn pre-filter, sand filter, layered activated carbon-softener resin filter, PP yarn micron filter, reverse osmosis (RO) membrane, PP yarn final filter and two ultraviolet (UV) disinfection …

Sustainable Smouldering For Waste-To-Energy: Scale, Heat Losses, And Energy Efficiency, Tarek L. Rashwan

Electronic Thesis and Dissertation Repository

Applied smouldering combustion is emerging as a highly energy efficient approach towards waste-to-energy. This thesis aims to better understand this potential by addressing a critical knowledge gap between laboratory scale smouldering research and large-scale applications. Altogether, new understanding in provided on the complex and dynamic interactions between the reaction zone (smouldering front) and the cooling zone (treated inert porous media) by integrating theory, experiments, analytical modelling, and global energy balance calculations. The experiments spanned a range of reactor sizes and smouldering conditions (from weak to robust) with dry (carbon) and wet (sludge) fuels mixed in sand. This work revealed that …

Experimental And Numerical Study Of Polymorphism In Crystallization Processes, Mengxing Lin

Electronic Thesis and Dissertation Repository

Polymorphism, which is exhibited in more than half of the active pharmaceutical ingredients, has a direct impact on the stability, bioavailability and processability of the product. Despite extensive studies on polymorphism in the field of crystal engineering, the control of polymorphism is still one of the most challenging tasks in pharmaceutical manufacturing.

The aim of this work is to crystallize the desired polymorph with the help of process modeling and process analytical technologies. First, we investigated the crystallization properties of imatinib mesylate, including polymorphism characterization, solubility measurement, polymorphic transformation and kinetic parameter estimation, as they are the fundamental information for …

Experimental Modelling Of Downburst And Downburst Line Outflows, Kyle Graat

Electronic Thesis and Dissertation Repository

The outflow velocity vector fields of simulated stationary thunderstorm downbursts and downburst lines were resolved in two plane orientations, vertical and horizontal, using a dense fluid release system and Particle Image Velocimetry. Single event releases were scaled to show agreement with past studies based on radial velocity magnitude and location and radial and vertical front propagation. The vortex trajectory of a single event using the vortex aspect ratio supported density's role in the outflow after the time and location of the maximum radial velocity. The interaction between two release events varied temporally and spatially and showed that the interaction region's …

Material Properties And Heat Transfer Parameters In Compression Molding Of Glass Mat Thermoplastics, Cheng Xu

Electronic Thesis and Dissertation Repository

The compression molding of glass mat thermoplastics (GMT) allows high volume manufacture of composite parts with a short production cycle. Computer simulation is often used to assist process development and optimization. Reliable simulation depends on input of material property parameters and accurate prediction of heat transfer. This thesis developed experimental methods to characterize material property and heat transfer process parameters. Results were obtained by applying the methods to a selected commercial GMT sheet. Heat transfer coefficients including convection coefficients during pre-heating and transfer, as well as contact conductance at sheet-mold interface were estimated by a parameter-fitting approach. Viscoelastic parameters of …

Machine Learning Prediction Of Mechanical And Durability Properties Of Recycled Aggregates Concrete, Itzel Rosalia Nunez Vargas

Electronic Thesis and Dissertation Repository

Whilst recycled aggregate (RA) can alleviate the environmental footprint of concrete production and the landfilling of colossal amounts of demolition waste, there need for robust predictive tools for its effects on mechanical and durability properties. In this thesis, state-of-the-art machine learning (ML) models were deployed to predict properties of recycled aggregate concrete (RAC). A systematic review was performed to analyze pertinent ML techniques previously applied in the concrete technology field. Accordingly, three different ML methods were selected to determine the compressive strength of RAC and perform mixture proportioning optimization. Furthermore, a gradient boosting regression tree was used to study the …

Development Of An Optical Guide For Parabolic Dish Solar Collectors, Zane Charran

Electronic Thesis and Dissertation Repository

With the possibility of a global energy crisis on the horizon, the need for renewable energy processes is more crucial than ever before. Solar energy, specifically solar concentrated collectors can provide a green alternative to fossil fuel consumption, but several factors need to be considered to improve their efficiency and make them viable. The present research is aimed at the development of a novel “Optical Guide” to improve performance of traditional thermal receivers in Parabolic Dish Solar Collectors for use in a domestic solar water heater with PCM latent heat storage integration. Two ray trace programs, SolTrace and Tracer were …

Assessment Of The Performance Of Field-Scale Bioretention Systems To Reduce Phosphorus Loads From Urban Stormwater, Jaeleah J. Goor

Electronic Thesis and Dissertation Repository

High nutrient loading can degrade surface water quality worldwide. Bioretention systems are low impact development stormwater management features designed to remove pollutants, including phosphorus (P), from urban stormwater runoff. In this study, two field-scale bioretention systems installed in London, Ontario, Canada were monitored to develop detailed understanding of P behaviour and the hydro-biogeochemical mechanisms that govern overall P retention. Net retention of total P and dissolved organic P, and net release of soluble reactive P (SRP) and total dissolved P were observed. Prolonged input of road de-icing salts (NaCl) in winter and early spring may result in high P release …

The Effect Of Free-Stream Turbulence On Turbulent Boundary Layers And Convective Heat Transfer From Flat Plates, Ivian Carolina Alfaia De Magalhaes

Electronic Thesis and Dissertation Repository

The present work investigates the effect of free-stream turbulence (FST) on turbulent boundary layers and forced convective heat transfer from flat plates. High resolution, 2-D and 3-D, steady Reynolds-Averaged Navier-Stokes (RANS) simulations using Computational Fluid Dynamics (CFD) techniques were performed to analyze the influence of different free-stream conditions, such as turbulence intensity (TI), integral length scale (L_u) and free-stream velocity (U_o) on local and total skin friction and convective heat transfer coefficients (CHTC), as well as on turbulent boundary layer parameters (boundary layer thickness and momentum thickness). The present study shows that …

Biomechanics Of Trees Under Extreme Wind Loading Events, Mojtaba Dargahi

Electronic Thesis and Dissertation Repository

For urban planners, arborists and foresters, understanding tree stability under self-weight and applied loads from wind and snow is important when developing management strategies to reduce the risk of damage from these abiotic agents. Current predictive approaches are generally empirical and based on a posteriori surveys of failures. A more rigorous engineering approach to understanding response phenomenon in trees subjected to extreme winds has been attempted herein. The size of trees and their architecture (shape and structure) greatly influence their mechanical stability under dynamic loading. Considering trees as porous media, wind loads on them are affected by their resistance to …

Measurement And Modeling Of Micro Residual Stresses In Pure Zirconium And Zr-2.5nb Polycrystals, Abdulla Alawadi

Electronic Thesis and Dissertation Repository

In CANada Deterium Uranium (CANDU) nuclear reactors, Zr-2.5Nb alloy pressure tubes separate the hot water and cold moderator. Pressure tubes are susceptible to the diffusion of hydrogen from water and formation of a brittle phase called zirconium hydrides. The diffusion and formation of hydrides are affected by the state of stresses within the tubes. As such, it is of great significance to understand the source of the stresses that develop within the tubes. This thesis focuses on the characterization of the micro and nano scale residual stresses that develop in pure zirconium and Zr-2.5Nb polycrystals. With using three-dimensional synchrotron X-ray …

Hydrostatic Performance Of Reinforced Concrete Pipe For Infiltration, Lui Sammy Wong

Electronic Thesis and Dissertation Repository

Groundwater infiltration into underground sewer systems has long been a costly issue for municipalities. With reinforced concrete pipe (RCP) being a primary option for sewer systems, existing hydrostatic testing methods conducted by manufacturers to measure internal pipe pressure, as required by specifications, do not reflect in-situ external hydrostatic conditions. This thesis records the development of a novel testing method to evaluate the RCP joint performance for infiltration. The test is safe and easy to conduct by RCP producers at the factory. The test method mimics field conditions of possible RCP joint gap and joint offset. Over 100 tests were conducted, …

Ultimate And Serviceability Limit States Of Large Shallow Foundations Under Combined Loading, Pengpeng He

Electronic Thesis and Dissertation Repository

Estimation of the bearing capacity and deformations of large shallow foundations under combined loadings can be of great significance. Some geotechnical design guidelines recommend the failure load envelope method for ultimate limit state analysis. Since many investigations of this method focus primarily on undrained failure envelopes using unlimited-tension interfaces, zero-tension interfaces have not been well investigated. In addition, less work is available on drained failure envelopes. For serviceability limit states, the majority of approaches used are based on uncoupled, isotropic assumptions. Further work needs to be done on more appropriate elastic solutions for combined loadings.

General VHMT failure envelopes for …

A Simple, Realistic Walled Phantom For Intravascular And Intracardiac Applications., Hareem Nisar, John Moore, Roberta Piazza, Efthymios Maneas, Elvis C S Chen, Terry M Peters

Robarts Imaging Publications

PURPOSE: This work aims to develop a simple, anatomically and haptically realistic vascular phantom, compatible with intravascular and intracardiac ultrasound. The low-cost, dual-layered phantom bridges the gap between traditional wall-only and wall-less phantoms by showing both the vessel wall and surrounding tissue in ultrasound imaging. This phantom can better assist clinical tool training, testing of intravascular devices, blood flow studies, and validation of algorithms for intravascular and intracardiac surgical systems.

METHODS: Polyvinyl alcohol cryogel (PVA-c) incorporating a scattering agent was used to obtain vessel and tissue-mimicking materials. Our specific design targeted the inferior vena cava and renal bifurcations which were …