Self-Healing Of Concrete Under Diverse Environmental Exposure, Ahmed Ramadan Suleiman

Electronic Thesis and Dissertation Repository

Self-healing efficiency of cement-based materials has so far been evaluated mostly through the healing of surface cracks, without adequately capturing the dominant effects of environmental exposure or accurately quantifying the volume of cracks healed. In addition, the effects of diverse additions such as silica-based materials, swelling agents, superabsorbent polymers, and carbonating minerals on self-healing performance under different environmental exposure, remain largely unexplored.

In this dissertation, multiple test methods were used to investigate self-healing of cracks in cement mortar incorporating metakaolin, bentonite, fly ash, superabsorbent polymers, and calcium carbonate microfiller under different environmental exposure (i.e. cold and hot temperatures, high and …

Design And Implementation Of Anomaly Detections For User Authentication Framework, Iman Abu Sulayman

Electronic Thesis and Dissertation Repository

Anomaly detection is quickly becoming a very significant tool for a variety of applications such as intrusion detection, fraud detection, fault detection, system health monitoring, and event detection in IoT devices. An application that lacks a strong implementation for anomaly detection is user trait modeling for user authentication purposes. User trait models expose up-to-date representation of the user so that changes in their interests, their learning progress or interactions with the system are noticed and interpreted. The reason behind the lack of adoption in user trait modeling arises from the need of a continuous flow of high-volume data, that is …

Role Of Groundwater-Lake Interactions On The Behavior Of Chemicals In A Nearshore Aquifer, Sabina Rakhimbekova

Electronic Thesis and Dissertation Repository

It is well recognized that groundwater-surface water interactions play an important role in controlling the flux of groundwater-derived inorganic chemicals to surface waters. While these interactions have been well-studied in marine, and river and stream settings, the influence of these interactions on chemical fluxes to large lakes is poorly understood. Nearshore aquifers adjacent to inland coastal waters, such as the Great Lakes, are characterized by dynamic flow patterns and the mixing of groundwater and lake water, which have distinct chemical compositions. This sets up an important reaction zone in the nearshore aquifer that may modify the fate of groundwater-derived chemicals …

Partial Nitritation Anammox Process For Sidestream Wastewater Treatment In Mabr Technology, Panagiota Stamatopoulou

Electronic Thesis and Dissertation Repository

There has been an increased interest in alternative wastewater treatment systems to improve nutrients removal and energy consumptions while achieving acceptable discharge limits. Wastewater treatment plants (WWTP) have shifted their interest in treating the sidestream wastewater; a reject liquid post anaerobic digestion, rich in ammonium-nitrogen. A dedicated sidestream wastewater treatment unit has become an attractive option with the finding of a relatively new species of bacteria, anaerobic ammonium oxidizers (anammox), able to convert ammonium and nitrite into nitrogen gas. However, anammox bacteria are sensitive in environmental changes, and in combination with their low growth rate, it is challenging to establish …

Effects Of Impurities On Calcium Oxalate Crystallization As Measured By Atomic Force Microscopy, Himasha Wijesekara

Electronic Thesis and Dissertation Repository

Calcium oxalate crystals are found in kidney stones as either calcium oxalate monohydrate (COM) or calcium oxalate dihydrate (COD). COM crystals are the most abundant form as they are thermodynamically more stable than COD crystals under physiological conditions. Certain aspartic acid-rich molecules such as osteopontin (OPN) are known to affect stone formation by inhibiting COM and COD growth. We have studied COM {010} and COD {100} faces in the presence of OPN, poly-aspartic acid (poly-ASP) and synthetic peptides derived from OPN to investigate the inhibitor mechanism.

We observed that poly-ASP preferentially inhibits one particular direction of {010} faces on COM …

Algorithms For Mappings And Symmetries Of Differential Equations, Zahra Mohammadi

Electronic Thesis and Dissertation Repository

Differential Equations are used to mathematically express the laws of physics and models in biology, finance, and many other fields. Examining the solutions of related differential equation systems helps to gain insights into the phenomena described by the differential equations. However, finding exact solutions of differential equations can be extremely difficult and is often impossible. A common approach to addressing this problem is to analyze solutions of differential equations by using their symmetries. In this thesis, we develop algorithms based on analyzing infinitesimal symmetry features of differential equations to determine the existence of invertible mappings of less tractable systems of …

Anaerobic Digestion Modeling Of A High Rate Acidification Pre-Treatment Technology, Connor Pritty

Electronic Thesis and Dissertation Repository

Through the application of a computerized model (BioWin), anaerobic co-digestion (AcoD) of source separated organics (SSO) and a high rate acidification technology (pretreatment) for a conventional wastewater treatment plant was reviewed. Through this combined approach of high rate acidification, and co-digestion techniques it was found that the experimental modeling scenarios offered increases when compared to the existing base scenario production levels. With the addition of the high rate acidification technology and application of source separated organics the maximum increases in biogas production came when an OLR of 5.24 kg-COD/m³/day and 97g COD/L/d was experimentally modeled. It is therefore, recommended that …

Miniature Cone Penetration Tests With Shear Wave Velocity And Electrical Resistivity Measurements In Characterization Of Silica Sand, Ronit Ganguly

Electronic Thesis and Dissertation Repository

Geotechnical engineering design and analysis require sound identification and characterization of in-situ soil. To characterize is to gather information about the engineering properties of a particular soil which will affect the performance of any structure built on it. As a result of complications associated with the retrieving of undisturbed samples of cohesionless soils, calibration chamber-based experiments under controlled laboratory settings are used for the determination of several geotechnical engineering parameters. The capability of a reduced-scale calibration chamber-based cone penetration testing system along with shear wave velocity and electrical resistivity measurements, to better characterize in-situ soil is examined in this study. …

Examining The Role Of Integration Experiences In Shaping Immigrants’ Post-Migration Food Choices And Eating Practices In Ontario, Canada, Eunjeong Eugena Kwon

Electronic Thesis and Dissertation Repository

Despite the extensive literature on immigrants’ post-migration dietary transitions and their implications for long-term health and well-being, little research has been conducted to link these processes to their integration experiences. This dissertation contributes to the current literature by examining the interrelationship between immigrants’ integration experiences – especially their economic integration – and their post-migration food choices and eating practices.

The first integrated article (Chapter 2) draws on qualitative interviews with 38 recent immigrants in two Ontario cities (Toronto and London) in Canada. First, this chapter focuses on illustrating recent immigrants’ general experiences in managing their post-migration food choices and eating …

Biomechanical Analysis Of Open-Skull High-Rate Traumatic Brain Injury Using Finite Element Mouse Brain Model, Lihong Lu

Electronic Thesis and Dissertation Repository

To better understand traumatic brain injury (TBI), it is necessary to correlate with injuries, which are observed from in vivo laboratory experiments, to brain mechanical responses, which can so far be best predicted by finite element (FE) models. Firstly, a previously validated FE model was improved to investigate the effect of repeated impacts and lateral movements on brain responses to ensure the accuracy and reproducibility of controlled cortical impact (CCI) across different labs. Then, a new FE mouse brain model with the detailed three-dimensional (3D), non-linear vasculature was developed to study how the vasculature affected brain response in CCI and …

Resignation Or Resistance? Examining The Digital Privacy Attitudes And Behaviours Of East Yorkers, Kaitlyn Cavacas

Electronic Thesis and Dissertation Repository

Digital technologies have become enmeshed in everyday life causing the public to become exposed to potential privacy risks through data collection and aggregation practices. Further, the upsurge in use of social networking platforms has also created opportunities for privacy violations through institutional and social surveillance. Employing a qualitative thematic analysis, this study explores how adults (N=101) living in East York, Toronto, navigate privacy through their use of the internet and digital services. Participants expressed feelings of mistrust, loss of control, resignation, and perceived self-unimportance with regards to their digital data. Importantly, others noted their desire and attempts to …

Enriched Derivators, James Richardson

Electronic Thesis and Dissertation Repository

In homotopical algebra, the theory of derivators provides a convenient abstract setting for computing with homotopy limits and colimits. In enriched homotopy theory, the analogues of homotopy (co)limits are weighted homotopy (co)limits. In this thesis, we develop a theory of derivators and, more generally, prederivators enriched over a monoidal derivator E. In parallel to the unenriched case, these E-prederivators provide a framework for studying the constructions of enriched homotopy theory, in particular weighted homotopy (co)limits.

As a precursor to E-(pre)derivators, we study E-categories, which are categories enriched over a bicategory Prof(E) associated to E. We prove a number of fundamental …

High-Pressure Studies On The Transition From Red Phosphorus To Black Phosphorus, Heng Xiang

Electronic Thesis and Dissertation Repository

Black phosphorus (BP) is a promising material in many research fields. However, the transition process from amorphous red phosphorus (ARP) is elusive and hence hinders large scale synthesis and applications. This work describes the application of the high-pressure method to study the transition process from ARP to BP.

In this thesis, the following three objectives were achieved: (1) to understand the mechanism of the transition, (2) to facilitate the synthesis of BP by taking the advantage of less pure ARP, (3) to propose new methods of synthesizing BP-based materials, such as the moderately oxidized BP and the black phosphorus/ amorphous …

Public Interest In Razón Pública: A Data-Driven Network Analysis, Emilio Calderon Reyes

Electronic Thesis and Dissertation Repository

This thesis is a case study based on a network analysis of the magazine Razón Pública. This project took an inductive, data-driven approach to public interest in the context of a specific digital network. The main objectives were to characterize the magazine’s authors and subscribers, identify its prevalent news topics, and validate to what extent subscribers agree that the resulting topics are of public interest or not. In order to achieve these objectives, a mixed methodology was used; it consisted of combining Natural Language Processing (NLP) techniques -keyword network, n-grams analysis, and Latent Dirichlet Allocation (LDA) topic modeling-, qualitative …

Objective Estimation Of Tracheoesophageal Speech Quality, Yousef S Ettomi Ali

Electronic Thesis and Dissertation Repository

Speech quality estimation for pathological voices is becoming an increasingly important research topic. The assessment of the quality and the degree of severity of a disordered speech is important to the clinical treatment and rehabilitation of patients. In particular, patients who have undergone total laryngectomy (larynx removal) produce Tracheoesophageal (TE) speech. In this thesis, we study the problem of TE speech quality estimation using advanced signal processing approaches. Since it is not possible to have a reference (clean) signal corresponding to a given TE speech (disordered) signal, we investigate in particular the non-intrusive techniques (also called single-ended or blind approaches) …

Energy Modelling To Evaluate The Thermal Regulation Of Aquaculture Raceways Using Geothermal Heat Exchange, Mitchell H. Kuska

Electronic Thesis and Dissertation Repository

Raceways are used in the aquaculture industry to farm fish species that swim against an upstream current. Raceways often draw water from a large waterbody and hence, their temperature changes due to seasonal variation, which directly affect the production yield. This study investigates a novel approach to regulate the raceway water temperature in a sustainable way by utilizing geothermal energy exchange. Energy models were developed to simulate heat transfer in a geothermal borehole heat exchange system and in the raceway system. The two models were then coupled to simulate the thermal regulation of the raceway water via borehole heat exchangers. …

The Co-Delivery Of Syngeneic Adipose-Derived Stromal Cells And Macrophages On Decellularized Adipose Tissue Bioscaffolds For In Vivo Soft Tissue Regeneration, Hisham A. Kamoun

Electronic Thesis and Dissertation Repository

Decellularized adipose tissue (DAT) bioscaffolds are a promising platform for the delivery of pro-regenerative cell populations with the goal of promoting adipose tissue regeneration. The current study investigated the effects of seeding DAT bioscaffolds with syngeneic bone marrow-derived macrophages and/or adipose-derived stromal cells (ASCs) on in vivo soft tissue regeneration. Methods were established to derive the macrophages from MacGreen mice, which were dynamically seeded onto the DAT scaffolds alone or in combination with ASCs. Seeded and unseeded scaffolds were implanted subcutaneously into C57Bl/6 mice. At 2 and 4 weeks, cell infiltration, angiogenesis, and adipogenesis were analyzed through histology and immunohistochemistry. …

Numerical And Semi-Analytical Estimation Of Convective Heat Transfer Coefficient For Buildings In An Urban-Like Setting, Anwar Demsis Awol

Electronic Thesis and Dissertation Repository

Urban building arrangements such as packing density, orientation and size are known to influence the microclimate surrounding each building. Studies on the impact of urban microclimatic changes on convective heat transfer coefficient (CHTC) from a stock of buildings, however, have been rare in surveyed literature. The present study focuses on numerical and analytical investigation of CHTC from building-like models with homogeneous set of equal and unequal planar and frontal densities. Consequently, the study discusses the CHTC response in relation to broader changes in the urban surface form. Part of the process involves the development of a simplified one-dimensional semi-analytical CHTC …

Leveraging Cloud-Based Nfv And Sdn Platform Towards Quality-Driven Next-Generation Mobile Networks, Hassan Hawilo

Electronic Thesis and Dissertation Repository

Network virtualization has become a key approach for Network Service Providers (NSPs) to mitigate the challenge of the continually increasing demands for network services. Tightly coupled with their software components, legacy network devices are difficult to upgrade or modify to meet the dynamically changing end-user needs. To virtualize their infrastructure and mitigate those challenges, NSPs have started to adopt Software Defined Networking (SDN) and Network Function Virtualization (NFV). To this end, this thesis addresses the challenges faced on the road of transforming the legacy networking infrastructure to a more dynamic and agile virtualized environment to meet the rapidly increasing demand …

The Effects Of Turbulent Cross-Winds On Combusting Jets At Low Velocity Ratios, Md Mahbub Hossain

Electronic Thesis and Dissertation Repository

Gas flares have been distinguished as a potential major source of hydrocarbon emissions from refineries and chemical plants. Flaring is the burning of waste gasses through a flare stack or other combustion device. By generating atmospheric turbulence in wind tunnel, an in-depth study has been conducted to capture the mechanics involving the reactive jet and stack-wake regions, which resembles the real world scenario of gas flaring, but at a reduced scale. In this study, a methodology has been described to generate atmospheric turbulence by passive grid to obtain the ideal turbulence intensities (I_u) and length scales (L_{x …}

Design And Analysis Of A Compliant 3d Printed Energy Harvester Package For Knee Implants, Geofrey Yamomo

Electronic Thesis and Dissertation Repository

Instrumented implants provide the potential to measure the in vivo tibiofemoral forces that are transmitted through total knee replacements (TKR). The continuous feedback from instrumented implants can be used to objectively justify actions to reduce the risk of implant failure. The main obstacle in developing “smart implants” is reliably powering such devices. Energy harvesting mechanisms, such as the triboelectric effect, can be leveraged to produce usable electricity and measure the transmitted loads in TKRs. A compliant package that interlocks with commercially available TKR components was designed to house triboelectric generators (TEG). Prototypes were more compliant than what was expected from …

Albert Forms, Quaternions, Schubert Varieties & Embeddability, Jasmin Omanovic

Electronic Thesis and Dissertation Repository

The origin of embedding problems can be understood as an effort to find some minimal datum which describes certain algebraic or geometric objects. In the algebraic theory of quadratic forms, Pfister forms are studied for a litany of powerful properties and representations which make them particularly interesting to study in terms of embeddability. A generalization of these properties is captured by the study of central simple algebras carrying involutions, where we may characterize the involution by the existence of particular elements in the algebra. Extending this idea even further, embeddings are just flags in the Grassmannian, meaning that their study …

Sodium-Glucose Cotransporter-2 Inhibitor Use And The Risk Of Acute Kidney Injury In Older Adults In Routine Clinical Practice: A Population-Based Cohort Study, Carina Iskander

Electronic Thesis and Dissertation Repository

Regulatory agencies warn about acute kidney injury (AKI) risk following sodium-glucose cotransporter-2 (SGLT2) inhibitor use. This population-based retrospective cohort study in Ontario, Canada quantified the 90-day AKI risk in older adults who were newly dispensed either SGLT2 inhibitors or dipeptidyl peptidase-4 (DPP4) inhibitors in an outpatient setting between 2015 and 2017. Risk ratios (RR) were obtained using modified Poisson regression and risk differences using binomial regression. Relative to new use of a DPP4 inhibitor, initiation of an SGLT2 inhibitor was associated with a lower 90-day risk of a hospital encounter with AKI: 216 events in 19,611 patients (1.10%) versus 388 …

Cluster-Based Chained Transfer Learning For Energy Forecasting With Big Data, Yifang Tian

Electronic Thesis and Dissertation Repository

Smart meter popularity has resulted in the ability to collect big energy data and has created opportunities for large-scale energy forecasting. Machine Learning (ML) techniques commonly used for forecasting, such as neural networks, involve computationally intensive training typically with data from a single building/group to predict future consumption for that same building/group. With hundreds of thousands of smart meters, it becomes impractical or even infeasible to individually train a model for each meter. Consequently, this paper proposes Cluster-Based Chained Transfer Learning (CBCTL), an approach for building neural network-based models for many meters by taking advantage of already trained models through …

Clinical Application Of 3d Ultrasound In Neonatal Intraventricular Hemorrhage, Priyanka Roy

Electronic Thesis and Dissertation Repository

Preterm neonates are at risk for intraventricular hemorrhage (IVH) and subsequent post-hemorrhagic hydrocephalus (PHH). A well-accepted interventional therapy for PHH is ventricular tap (VT). Permanent treatment, ventriculo peritoneal shunt surgery (VPS) is required in the case of some neonates under some conditions (weight, immunological status, CSF protein level) who receive multiple interventions. The objective of this study was to apply a 3D ultrasound system clinically to determine CSF volume within the ventricle, to guide the neurosurgeon regarding the amount of CSF should be removed during every intervention, which lateral ventricle is better to intervene and to predict the possibilities of …

Prufrock: A Monodrama For Baritone And Electronics, Daniel Gardner

Electronic Thesis and Dissertation Repository

Prufrock is a musical dramatization of T.S. Eliot’s, The love song of J. Alfred Prufrock for solo baritone and electronics; a full performance of the work should take approximately forty (40) minutes.

The work uses text from both Eliot’s original publication and a section removed from the text called Prufrock’s Pervigilium—first published in Christopher Ricks’s Inventions of the March Hare—and superimposes a narrative onto Eliot’s monologue of a man whose internal experience differs wildly from reality. As such Prufrock emphasizes the psychodramatic elements of the original text, reflecting them through the use of “auditory illusions” (particularly those described …

Spatial And Temporal Characteristics Of Temperature-Precipitation Covariability Across Canada In A Changing Climate, Harsimrenjit Singh

Electronic Thesis and Dissertation Repository

Changes in the regional characteristics of temperature and precipitation can intensify the occurrence and severity of extreme events such as rain-on-snow induced flooding, droughts and wildfires. Analyzing these climate variables in isolation without considering their interdependencies might result in severe underestimation of their combined effects. In this study, copula functions are used to describe the joint behaviour of temperature and precipitation across Canada over a historical period of 1910-present using observations and further till the end of the 21st century using three large ensembles of regional climate models. Moreover, given the lack of observation data over Canada, gridded datasets are …

X-Ray Absorption Spectroscopy, X-Ray Diffraction And Optical Luminescence Studies Of Phase Transition Of Titania Nanotubes, Lu Yao

Electronic Thesis and Dissertation Repository

The one-dimensional (1D) TiO₂ nanotubes (NTs) and their derivatives have been extensively studied due to their wide applications, such as photocatalysts, solar cell, paints and so on. Since TiO₂ has a wide band gap (~3.0 eV), its photo-absorption as the photocatalyst only occurs in the UV region that wastes mostly solar energy. Therefore, the solution to higher photocatalytic efficiency has been sought for some time. This thesis presents a study of the size-dependent phase transitions of TiO₂ NTs using synchrotron-based X-ray techniques. The chemical environment including local symmetry and the luminescence origin of the TiO₂ NTs …

The Role Of Adult Hippocampal Neurogenesis In Depression-Relevant Reward-Related Behaviours, Katrina Zmavc

Electronic Thesis and Dissertation Repository

The variability in the symptomatology of depressive disorders and antidepressant treatment response has led to an increased interest in the molecular, cellular, and circuit mechanisms of many aspects of affect. Evidence suggests a reduction in adult hippocampal neurogenesis (AHN) is associated with an increase in depression-like behaviour, though much of this evidence has been from studies using aversive tests (e.g., forced swim test). Here, I used touchscreen operant chambers, which allow for non-aversive and translational testing, to test the hypothesis that AHN plays a contributing role in emotion regulation. A panel of three touchscreen tests were chosen to assess different …

Reliability And Validity Of Two Performance-Based Outcome Measures In Rehabilitation Following Total Knee Arthroplasty, Jennifer L. Van Bussel

Electronic Thesis and Dissertation Repository

Objectives: Performance-based outcome measures (PBOM) are suggested to evaluate change in function during rehabilitation after total knee arthroplasty (TKA). The purpose of this study was to evaluate the measurement properties of the 30-Second Chair Stand Test (30CST) and 10-Metre Walk Test (10MWT) in patients following TKA.

Methods: Eighty-three patients completed two PBOM on three occasions following surgery. Patients also completed the Western Ontario and McMaster Universities Osteoarthritis Index and Global Rating of Change (GRC).

Results: Intraclass correlation coefficients ranged from 0.82 to 0.96. The standard errors of measurement at 6 and 12 weeks postop, respectively, were: 30CST ±0.67 and ±0.79, …