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Full-Text Articles in Engineering

Bouncing Dynamics Of A Class Of Mem/Nem Switching Systems, Mohamed Bognash Jan 2019

Bouncing Dynamics Of A Class Of Mem/Nem Switching Systems, Mohamed Bognash

Electronic Thesis and Dissertation Repository

The aim of the present research is to understand the bouncing dynamic behavior of NEM/MEM switches in order to improve the switch performance and reliability. It is well known that the bouncing can dramatically degrade the switch performance and life; hence, in the present study, bouncing dynamics of a cantilever-based NME/MEM switch has been studied in detail. To this end, a model of a MEM switch that incorporates electrostatic force, squeeze film air damping force as well as asperity-based contact force has been proposed for an electrostatically actuated switch. An actuation force due to piezoelectric effects is further ...


Heat Of Hydration Thermal Performance And Flexural Capacity Of Stainless-Steel Reinforced Concrete Sections, Mokhtar Khalifa Jan 2019

Heat Of Hydration Thermal Performance And Flexural Capacity Of Stainless-Steel Reinforced Concrete Sections, Mokhtar Khalifa

Electronic Thesis and Dissertation Repository

Stainless steel (SS) is increasingly used in the construction field due to its high strength and corrosion resistance. However, its coefficient of thermal expansion is different from that of concrete. This difference raises concerns about the potential for concrete cracking during the hydration process. To address this concern, a thermal-structural finite element model was developed to predict the stresses in SS reinforced concrete (RC) sections during the hydration process. Different curing regimes were taken into consideration. The analysis was performed in two stages. First, a transient thermal analysis was performed to determine the temperature distribution within the concrete section as ...


Secured Data Masking Framework And Technique For Preserving Privacy In A Business Intelligence Analytics Platform, Osama Ali Dec 2018

Secured Data Masking Framework And Technique For Preserving Privacy In A Business Intelligence Analytics Platform, Osama Ali

Electronic Thesis and Dissertation Repository

The main concept behind business intelligence (BI) is how to use integrated data across different business systems within an enterprise to make strategic decisions. It is difficult to map internal and external BI’s users to subsets of the enterprise’s data warehouse (DW), resulting that protecting the privacy of this data while maintaining its utility is a challenging task. Today, such DW systems constitute one of the most serious privacy breach threats that an enterprise might face when many internal users of different security levels have access to BI components. This thesis proposes a data masking framework (iMaskU: Identify ...


Aversion And Warning Factors For Assessing Existing Reinforced Concrete Structures, Marcie Van Weerdhuizen Dec 2018

Aversion And Warning Factors For Assessing Existing Reinforced Concrete Structures, Marcie Van Weerdhuizen

Electronic Thesis and Dissertation Repository

In a world of aging infrastructure, sustainability initiatives require additional investment in the assessment of existing reinforced concrete structures. Reliability-based assessment should minimize costs by reducing conservatism, while ensuring levels of safety equivalent to those for new designs. Current Canadian and US provisions assign target reliability levels for structural assessment based on criteria including occupancy type, expected failure behaviour, and the eect of element failure on the overall structural integrity. These criteria are defined using discrete and qualitative parameter values. It is shown that the true structural conditions can be better represented by verifying the applicability and completeness of these ...


Corrosion Dynamics Of Carbon Steel In Used Fuel Container Environments, Dan Guo Dec 2018

Corrosion Dynamics Of Carbon Steel In Used Fuel Container Environments, Dan Guo

Electronic Thesis and Dissertation Repository

The current Canadian used nuclear fuel container (UFC) design uses a pressure‑grade carbon steel (CS) vessel with its outer surface coated with a thin layer of copper. One concern regarding the structural integrity of the UFC design is the potential internal corrosion of the CS vessel. Moisture trapped inside a UFC could condense within the gap between the hemispherical head and the cylindrical body of the vessel. The internal UFC environment will be exposed to a continuous flux of ionizing radiation arising from the decay of radionuclides trapped in the used UO2 fuel matrix.

This thesis research project ...


Experimental Testing And Modeling Of Partial Nitrification At Different Temperatures, Xiaoguang Liu Dec 2018

Experimental Testing And Modeling Of Partial Nitrification At Different Temperatures, Xiaoguang Liu

Electronic Thesis and Dissertation Repository

Nitrogen in wastewater treatment plant effluents has adverse environmental effects on aquatic systems. Excessive concentrations of nitrogen in water bodies can result in the depletion of dissolved oxygen, deterioration of water quality, and shifts of biotic community. Conventional biological nitrogen removal (BNR) processes consume high energy for nitrification and require external carbon for denitrification. Alternatively, partial nitrification is of interest as an emerging technology for its lower need of organic carbon addition and cost savings in aeration. In this study, the main objectives are: 1- developing a mathematical model involving operational parameters for the determination of successful partial nitrification conditions ...


Current Implementation Of The Flooding Time Synchronization Protocol In Wireless Sensor Networks, Asma Khalil Dec 2018

Current Implementation Of The Flooding Time Synchronization Protocol In Wireless Sensor Networks, Asma Khalil

Electronic Thesis and Dissertation Repository

Time synchronization is an issue that affects data accuracy within wireless sensor networks (WSNs). This issue is due to the complex nature of the wireless medium and can be mitigated with accurate time synchronization. This research focuses on the Flooding Time Synchronization Protocol (FTSP) since it is considered as the gold standard for accuracy in WSNs. FTSP minimizes the synchronization error by executing an algorithm that creates a unified time for the network reporting micro-second accuracy. Most synchronization protocols use the FTSP implementation as a benchmark for comparison. The current and only FTSP implementation runs on the TinyOS platform and ...


Propane Oxidative Dehydrogenation Under Oxygen-Free Conditions Using Novel Fluidizable Catalysts: Reactivity, Kinetic Modeling And Simulation Study, Samira Rostom Nov 2018

Propane Oxidative Dehydrogenation Under Oxygen-Free Conditions Using Novel Fluidizable Catalysts: Reactivity, Kinetic Modeling And Simulation Study, Samira Rostom

Electronic Thesis and Dissertation Repository

Propane oxidative dehydrogenation (PODH) was studied using VOx/γAl2O3 and VOx/ZrO2-γAl2O3 (1:1 wt.%) catalysts, as well as consecutive propane injections under oxygen-free conditions. These catalysts were synthesized with 2.5, 5 and 7.5 wt.% vanadium loadings, and prepared using a wet saturation impregnation technique. Different characterization techniques were used to establish catalyst properties including NH3-TPD, pyridine FTIR and NH3-TPD kinetics. As well, PODH runs in the CREC Riser Simulator were developed under oxygen free atmospheres at 500-550°C, close to 1 atm., 10-20 ...


Quantification Of Uncertainties In Inline Inspection Data For Metal-Loss Corrosion On Energy Pipelines And Implications For Reliability Analysis, Tammeen Siraj Nov 2018

Quantification Of Uncertainties In Inline Inspection Data For Metal-Loss Corrosion On Energy Pipelines And Implications For Reliability Analysis, Tammeen Siraj

Electronic Thesis and Dissertation Repository

One of the major threats to the oil and gas transmission pipeline integrity is metal-loss corrosion. Pipeline operators periodically inspect the size of the metal loss corrosion in a pipeline using in-line inspection (ILI) tools to avoid pipe failure which may lead to severe consequences. To predict pipe failure efficiently, reliability-based corrosion management program is gaining popularity as it effectively incorporates all the uncertainties involved in the pipe failure prediction. The focus of the research reported in this thesis is to investigate the unaddressed issues in the reliability-based corrosion assessment to assist in better predicting pipe failure.

First, a methodology ...


Robust Earthquake Site Classification Assessment At Ontario Bridge Sites., Alex Bilson Darko Nov 2018

Robust Earthquake Site Classification Assessment At Ontario Bridge Sites., Alex Bilson Darko

Electronic Thesis and Dissertation Repository

Canadian seismic design guidelines classify subsurface ground conditions based on the average shear-wave velocity (VS) of the upper 30 meters (VS30). We seek to optimize a robust earthquake site classification procedure for Ontario bridge sites, assessed primarily from blind comparison of non-invasive VS depth profiling techniques. Non-invasive seismic testing is performed at 10 bridge sites in southern Ontario co-located with invasive penetration and/or borehole VS measurements. Non-invasive surface wave dispersion and site amplification functions are jointly inverted to retrieve VS profiles at each site. A general correlation between corrected VS and cone tip ...


Tibiotalar Arthrodesis: Development Of A Novel Jig And Alignment Guide, Adam Mathew Ropchan Nov 2018

Tibiotalar Arthrodesis: Development Of A Novel Jig And Alignment Guide, Adam Mathew Ropchan

Electronic Thesis and Dissertation Repository

Tibiotalar arthrodesis is a surgical procedure, used for the treatment of end-stage ankle arthrosis and instability. There are dozens of described procedures in the literature, all with varying rates of success. Two of the most common reasons for reoperation in tibiotalar arthrodesis are nonunion and infection; few studies have established any associations between patient/surgical factors and reoperation for nonunion and infection.

The first part of this thesis focuses on determining the rate of reoperation to the ipsilateral lower limb and if any patient/surgical factors are associated with reoperation for nonunion and infection. The second part of this thesis ...


Transient Analysis Of Full Scale And Experimental Downburst Flows, Junayed Chowdhury Nov 2018

Transient Analysis Of Full Scale And Experimental Downburst Flows, Junayed Chowdhury

Electronic Thesis and Dissertation Repository

Downbursts are highly transient natural phenomena which produce strong downdrafts evolving from a cumulonimbus cloud They induce an outburst of damaging winds on or near to the ground causing an immense damage to the ground mounted structures and aircrafts. This study investigates the transient nature of downbursts using wind speed records from full scale downburst events employing an objective methodology. This method can detect the abrupt change points in a downburst time series based on statistical parameters such as mean, standard deviation and linear trend. In addition to the analysis of the full scale downburst events, several large scale experimental ...


Use Of Regional Scale Field And Modelling Methods To Evaluate Nearshore Groundwater Discharge To A Large Glacial Lake, Hayley A. Wallace Ms. Nov 2018

Use Of Regional Scale Field And Modelling Methods To Evaluate Nearshore Groundwater Discharge To A Large Glacial Lake, Hayley A. Wallace Ms.

Electronic Thesis and Dissertation Repository

Groundwater discharge may be an important pathway for delivering pollutants to large lakes, but this pathway is poorly understood. Understanding the potential for groundwater discharge to deliver pollutants to lakes requires an evaluation of the magnitude and spatial variability of groundwater discharge to the lake, and the history of the discharging groundwater. The first objective of this thesis was to evaluate and quantify the spatial variability of groundwater discharge to a large glacial lake, Lake Simcoe, Ontario, using the naturally occurring radon isotope tracer (222Rn). Regional scale boat surveys were conducted along 80% of the Lake Simcoe shoreline using ...


Investigation And Validation Of Imaging Techniques For Mitral Valve Disease Diagnosis And Intervention, Claire Vannelli Nov 2018

Investigation And Validation Of Imaging Techniques For Mitral Valve Disease Diagnosis And Intervention, Claire Vannelli

Electronic Thesis and Dissertation Repository

Mitral Valve Disease (MVD) describes a variety of pathologies that result in regurgitation of blood during the systolic phase of the cardiac cycle. Decisions in valvular disease management rely heavily on non-invasive imaging. Transesophageal echocardiography (TEE) is widely recognized as the key evaluation technique where backflow of high velocity blood can be visualized under Doppler. In most cases, TEE imaging is adequate for identifying mitral valve pathology, though the modality is often limited from signal dropout, artifacts and a restricted field of view. Quantitative analysis is an integral part of the overall assessment of valve morphology and gives objective evidence ...


Continuous Monitoring Of Neutral Grounding Resistors And Reactors, Rahim Jafari Nov 2018

Continuous Monitoring Of Neutral Grounding Resistors And Reactors, Rahim Jafari

Electronic Thesis and Dissertation Repository

Electrical power system components are designed three-phase balanced and symmetric with the internal connection of wye or delta. The common point of the wye-connected equipment, which is called neutral, is impedance grounded for many reasons such as fault ride through by controlling transient overvoltages, and limiting the ground overcurrents. Depending on the application, different neutral impedance grounding methods exist that employ resistors or reactors with/without neutral grounding transformers. These apparatuses are known as Neutral Grounding Devices (NGD). The most well-known sort of NGDsarethe Neutral Grounding Resistor (NGR) and Neutral Grounding Reactor (NGL) which are the main focus of this ...


Experimental Investigation Of The Heat Source Orientation On The Transient Flow And Thermal Behaviour Of Phase Change Material During Phase Transition, Steven Jevnikar Nov 2018

Experimental Investigation Of The Heat Source Orientation On The Transient Flow And Thermal Behaviour Of Phase Change Material During Phase Transition, Steven Jevnikar

Electronic Thesis and Dissertation Repository

The present study reports the characterization of transient flow and transient thermal behavior of phase change material (PCM) during solid-liquid phase change (melting) through experimental investigation. Two specific aspects of the current work, both important in the field of latent heat thermal energy storage, are to investigate the influence of the flow behavior within liquid PCM on the melting and heat transfer processes, and the impact of heat source orientation on the underlying melting and heat transfer processes. A relationship between heat source orientation and the Nusselt number was discussed. The results show that the fluid velocity is critical for ...


Piston Modelling And Gas-Solid Mixing Characterization In Jbr, Tian Dong Cai Nov 2018

Piston Modelling And Gas-Solid Mixing Characterization In Jbr, Tian Dong Cai

Electronic Thesis and Dissertation Repository

The Jiggle Bed Reactor (JBR), a batch fluidized bed microreactor, is inexpensive and easy to operate with a small amount of solids. The main goal of this thesis was to provide practical tools for the design and operation of JBR systems that will ensure good gas-solids mixing.

A model was developed to predict the piston motion. The model uses four empirical parameters that change depending on the equipment characteristics. Two parameters characterize the gas supply to the piston and two parameters are used to describe the frictional forces on the piston. The model was validated with high speed video.

Experiments ...


Spectral And Energy Efficient Communication Systems And Networks, Abdulbaset Hamed Oct 2018

Spectral And Energy Efficient Communication Systems And Networks, Abdulbaset Hamed

Electronic Thesis and Dissertation Repository

In this thesis, design and analysis of energy- and spectral-efficient communication and cellular systems in micro wave and millimeter wave bands are considered using the following system performance metrics: i) Energy efficiency; ii) Spectral efficiency; iii) Spatial spectral efficiency; iv) Spatial energy efficiency, and v) Bit error rate. Statistical channel distributions, Nakagami-m and Generalized-K, and path loss models, Line of Sight (LOS) and Non-Line of Sight (NLOS), are used to represent the propagation environment in these systems. Adaptive M-QAM and M-CPFSK communication systems are proposed to enhance their efficiency metrics as a function of Signal-to-Noise Ratio (SNR) over the channel ...


Generalized Scattering-Based Stabilization Of Nonlinear Interconnected Systems, Anastasiia Usova Oct 2018

Generalized Scattering-Based Stabilization Of Nonlinear Interconnected Systems, Anastasiia Usova

Electronic Thesis and Dissertation Repository

The research presented in this thesis is aimed at development of new methods and techniques for stability analysis and stabilization of interconnections of nonlinear systems, in particular, in the presence of communication delays. Based on the conic systems' formalism, we extend the notion of conicity for the non-planar case where the dimension of the cone's central subspace may be greater than one. One of the advantages of the notion of non-planar conicity is that any dissipative system with a quadratic supply rate can be represented as a non-planar conic system; specifically, its central subspace and radius can be calculated ...


Electroflotation For Treatment Of Paint Wastewater: Experiments, Kinetics And Hydrodynamics, Syed Reza Mohtashami Oct 2018

Electroflotation For Treatment Of Paint Wastewater: Experiments, Kinetics And Hydrodynamics, Syed Reza Mohtashami

Electronic Thesis and Dissertation Repository

Electroflotation (EF) is a process used to remove suspended particles from water using the gas bubbles generated from the water electrolysis. This dissertation focuses on the fundamental principles and applications of EF in the treatment of industrial wastewaters, and in particular, treatment of automotive paint wastewater. In the first part, an extensive review of applications of electroflotation in the treatment of different categories of industrial wastewaters, including the fundamentals of the process, electrode materials, design aspects and process variables, is conducted. The second part is focusing on the kinetic study, statistical analysis and empirical modeling of available experimental data from ...


Development Of Digital Control Systems For Wearable Mechatronic Devices: Applications In Musculoskeletal Rehabilitation Of The Upper Limb, Tyler Desplenter Oct 2018

Development Of Digital Control Systems For Wearable Mechatronic Devices: Applications In Musculoskeletal Rehabilitation Of The Upper Limb, Tyler Desplenter

Electronic Thesis and Dissertation Repository

The potential for wearable mechatronic systems to assist with musculoskeletal rehabilitation of the upper limb has grown with the technology. One limiting factor to realizing the benefits of these devices as motion therapy tools is within the development of digital control solutions. Despite many device prototypes and research efforts in the surrounding fields, there are a lack of requirements, details, assessments, and comparisons of control system characteristics, components, and architectures in the literature. Pairing this with the complexity of humans, the devices, and their interactions makes it a difficult task for control system developers to determine the best solution for ...


Development Of Granulation Tissue Mimetic Scaffolds For Skin Healing, Adam Hopfgartner Oct 2018

Development Of Granulation Tissue Mimetic Scaffolds For Skin Healing, Adam Hopfgartner

Electronic Thesis and Dissertation Repository

Impaired skin healing is a significant and growing clinical concern, particularly in relation to diabetes, venous insufficiency and immobility. Previously, we developed electrospun scaffolds for the delivery of periostin (POSTN) and connective tissue growth factor 2 (CCN2), matricellular proteins involved in the proliferative phase of healing. This study aimed to design and validate a novel electrosprayed coaxial microsphere for the encapsulation of fibroblast growth factor 9 (FGF9), as a component of the POSTN/CCN2 scaffold, to promote angiogenic stability during wound healing. For the first time, we observed a pro-proliferative effect of FGF9 on human dermal fibroblasts (HDF) in vitro ...


Development Of Material Model Subroutines For Linear And Nonlinear Response Of Elastomers, Asim Gillani Oct 2018

Development Of Material Model Subroutines For Linear And Nonlinear Response Of Elastomers, Asim Gillani

Electronic Thesis and Dissertation Repository

The nature of elastomers has been extensively studied ever since the vulcanization of rubber in the 19th century. Elastomers have been heavily employed in various fields, such as automobile, aerospace, robotics, biomimetics, dynamics and energy harvesting. Due to their molecular nature, these materials display hyperelastic and viscous response when deformed. Their response has been studied in a number of works, which tend to explain their nature through the theory of polymer dynamics or using rheological models. As elastomers are designed as actuators, generators or artificial tissues with complex geometries, the need for finite element analysis to study their response is ...


A Biomechanical And Physiological Signal Monitoring System For Four Degrees Of Upper Limb Movement, Allison R. Goldman Sep 2018

A Biomechanical And Physiological Signal Monitoring System For Four Degrees Of Upper Limb Movement, Allison R. Goldman

Electronic Thesis and Dissertation Repository

A lack of adherence to prescribed physical therapy regimens in improper healing results in poor outcomes for those affected by musculoskeletal disorders (MSDs) of the upper limb. Societal and psychological barriers to proper adherence can be addressed through the system presented in this work consisting of the following components: an ambulatory biosignal acquisition sleeve, an electromyography (EMG) based motion repetition detection algorithm, and the design of a compatible capacitive EMG acquisition module.

The biosignal acquisition sleeve was untethered, unobtrusive to motion, contained only modular components, and collected biomechanical and physiological sensor data to form full motion profiles of the following ...


Non-Pilot Protection Of The Inverter-Dominated Ac Microgrid, Houman Lahiji Sep 2018

Non-Pilot Protection Of The Inverter-Dominated Ac Microgrid, Houman Lahiji

Electronic Thesis and Dissertation Repository

The main objective of this research is to develop reliable non-pilot protection and control strategies for the inverter-dominated microgrid. First, an improved Proportional-Derivative (PD) droop control strategy is proposed for enhanced disturbance response of the inverter-dominated AC microgrid. The proposed strategy significantly improves microgrid dynamic response and stability without requiring communication between distributed energy resources. Moreover, the impacts of large startup currents of induction motors on the stability and power quality of the inverter-dominated microgrid are investigates and recommendations for minimizing the associated adverse effects are made.

Subsequently, a fast, selective, and reliable protection strategy for the inverter-dominated microgrid is ...


New Algorithms For Locating Faults In Series Capacitive Compensated Transmission Lines, Tirath Bains Sep 2018

New Algorithms For Locating Faults In Series Capacitive Compensated Transmission Lines, Tirath Bains

Electronic Thesis and Dissertation Repository

The precise location of the fault in a series capacitive compensated transmission line (SCCTL) plays an integral part in limiting the maintenance time following its tripping due to the occurrence of a permanent fault. Since, an SCCTL acts as a huge corridor of power, its outage will result in huge monetary losses which are directly proportion to the time it remains out of service. In worst case scenario, the tripping of an SCCTL might lead to the cascaded tripping of the parallel transmission lines due to overloading. Therefore, the need for an accurate and robust fault location algorithm for the ...


Numerical Simulation Of Three-Phase Flows In The Inverse Fluidized Bed, Yunfeng Liu Sep 2018

Numerical Simulation Of Three-Phase Flows In The Inverse Fluidized Bed, Yunfeng Liu

Electronic Thesis and Dissertation Repository

The inverse three-phase fluidized bed has excellent potentials to be used in chemical, biochemical, petrochemical and food industries because of its high contact efficiency among each phase which leads to a good mass and heat transfer. The understanding of the hydrodynamics and flow structures in inverse three-phase fluidized beds is important for the design and scale up purposes.

A CFD model based on the Eulerian-Eulerian (E-E) approach coupled with the kinetic theory of the granular flow is successfully developed to simulate an inverse three-phase fluidization system. The proposed CFD model for the inverse three-phase fluidization system is validated by comparing ...


The Spanwise Structure Of The Roof-Level Turbulence In A Street Canyon Flow, Tomek Jaroslawski Sep 2018

The Spanwise Structure Of The Roof-Level Turbulence In A Street Canyon Flow, Tomek Jaroslawski

Electronic Thesis and Dissertation Repository

In the present work, for the first time, the spanwise organization of turbulent flow along an urban street canyon subjected to wind normal to the street axis using a boundary layer wind tunnel is systematically investigated.The effect of upstream roughness and canyon width on the turbulence in a street canyon flow is presented. Measurements in a horizontal plane were conducted at near roof-level of a street canyon using Stereoscopic Particle Image Velocimetry. Three upstream roughness arrays and two canyon width (W) to height (h) aspect ratios (AR = W / h = 1 and 3) were investigated. The results show a significant ...


Spraying Slurries: Impact Of Slurry Properties On Spray Characteristics And Agglomerate Formation In Fluidized Beds, Joshua Idowu Sep 2018

Spraying Slurries: Impact Of Slurry Properties On Spray Characteristics And Agglomerate Formation In Fluidized Beds, Joshua Idowu

Electronic Thesis and Dissertation Repository

Abstract

Fluid CokingTM is a process that upgrades Alberta’s heavy oil. The recycle stream in the process contains unwanted fines which could affect the interaction between the liquid feed and the bed particles and the tendency to form agglomerates. Agglomeration leads to lower product yields and vessel damage.

The impacts of slurry solids on spray stability and angle were measured in open air while the impacts on agglomerate stability and liquid distribution were studied in a fluidized bed. Particle properties were varied to understand the impact of the solids on agglomerates.

In open air, it was observed that ...


Electrospun Collagen Fibers For Tissue Regeneration Applications, Ying Li Sep 2018

Electrospun Collagen Fibers For Tissue Regeneration Applications, Ying Li

Electronic Thesis and Dissertation Repository

Tissue engineering aims to regenerate damaged and deceased tissue by combining cells with scaffold made from an appropriate biomaterial and providing a conducive environment to guide cell growth and the formation or regeneration of new tissue or organ. While collagen, an important material of the extracellular matrix (ECM), is a natural choice as a scaffold biomaterial, the conducive environment can only be created by having the ability to control the geometry, organization, structural and mechanical properties of the scaffold. Moreover, degradability and degradation rate control of the scaffold has to be taken into consideration too. In this work, we aim ...