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Full-Text Articles in Engineering

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 ...


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

Development Of Digital Control System 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 ...


Hydrogen Production By Photocatalytic Water Splitting Under Near-Uv And Visible Light Using Doped Pt And Pd Tio2, Bianca Rusinque Sep 2018

Hydrogen Production By Photocatalytic Water Splitting Under Near-Uv And Visible Light Using Doped Pt And Pd Tio2, Bianca Rusinque

Electronic Thesis and Dissertation Repository

Photocatalysis is a promising methodology for hydrogen production. It involves the use of an unlimited source of energy, sunlight, and a semiconductor material to split water with zero carbon emissions.

This Master’s thesis reports high efficiencies in terms of hydrogen production via water splitting using 2.0v/v% ethanol as scavenger, platinum and palladium as noble metals on TiO2 photocatalysts at three metal loadings (1.0, 2.5 and 5.0wt%). Both near UV and visible light were used in the studies developed. These photocatalysts were synthetized using a sol-gel method whose morphological properties were enhanced due to ...


Automatic Recall Of Lessons Learned For Software Project Managers, Tamer Mohamed Abdellatif Mohamed Aug 2018

Automatic Recall Of Lessons Learned For Software Project Managers, Tamer Mohamed Abdellatif Mohamed

Electronic Thesis and Dissertation Repository

Lessons learned (LL) records constitute a software organization’s memory of successes and failures. LL are recorded within the organization repository for future reference to optimize planning, gain experience, and elevate market competitiveness. However, manually searching this repository is a daunting task, so it is often overlooked. This can lead to the repetition of previous mistakes and missing potential opportunities, which, in turn, can negatively affect the organization’s profitability and competitiveness. In this thesis, we present a novel solution that provides an automatic process to recall relevant LL and to push them to project managers. This substantially reduces the ...


Field Test Of Electrokinetically-Delivered Thermally Activated Persulfate For Remediation Of Chlorinated Solvents In Clay, Nicholas Andrew Head Aug 2018

Field Test Of Electrokinetically-Delivered Thermally Activated Persulfate For Remediation Of Chlorinated Solvents In Clay, Nicholas Andrew Head

Electronic Thesis and Dissertation Repository

Due to extensive industrial applications, chlorinated solvents are among the most prevalent groundwater contaminants found at hazardous sites. Given their recalcitrant nature and adverse health effects upon exposure, effective remediation technologies are needed to treat sites impacted by chlorinated solvents. In-situ chemical oxidation (ISCO) has shown success; however, its performance is often hindered in low-permeability media due to the transport of oxidants in such soils being limited. This field-scale study investigated the novel approach of applying electrokinetics (EK) to enhance the delivery of persulfate and electrical resistance heating (ERH) to activate the delivered persulfate for low-permeability soil remediation. Results demonstrated ...


Synthesis And Drop-On-Demand Deposition Of Graphene Derivative Inks For Flexible Thin Film Electronics, Dogan M. Sinar Aug 2018

Synthesis And Drop-On-Demand Deposition Of Graphene Derivative Inks For Flexible Thin Film Electronics, Dogan M. Sinar

Electronic Thesis and Dissertation Repository

This dissertation presents methods for deposition and post-processing of Graphene-Carboxymethyl Cellulose (G-CMC) and Graphene Oxide (GO) aqueous functional inks using a custom drop-on-demand (DOD) printer to fabricate mechanically flexible, non-transparent and transparent thin film electronic devices. Thin films on flexible substrates find use in lightweight, low profile, and conformable electronic devices. Such devices can include chemical sensors, flexible RFID tags, bioelectronics circuits, lightweight electronics for space systems, and transparent electrodes for optoelectronic systems. The goal of this research project is to provide simple methods for fabrication of these devices using environmentally friendly and easy to synthesize functional inks. Therefore, two ...


Recurrent Neural Network Architectures Toward Intrusion Detection, Wafaa Anani Aug 2018

Recurrent Neural Network Architectures Toward Intrusion Detection, Wafaa Anani

Electronic Thesis and Dissertation Repository

Recurrent Neural Networks (RNN) show a remarkable result in sequence learning, particularly in architectures with gated unit structures such as Long Short-term Memory (LSTM). In recent years, several permutations of LSTM architecture have been proposed mainly to overcome the computational complexity of LSTM. In this dissertation, a novel study is presented that will empirically investigate and evaluate LSTM architecture variants such as Gated Recurrent Unit (GRU), Bi-Directional LSTM, and Dynamic-RNN for LSTM and GRU specifically on detecting network intrusions. The investigation is designed to identify the learning time required for each architecture algorithm and to measure the intrusion prediction accuracy ...


Dynamic Calibration Of Emg Signals For Control Of A Wearable Elbow Brace, Taylor Stanbury Aug 2018

Dynamic Calibration Of Emg Signals For Control Of A Wearable Elbow Brace, Taylor Stanbury

Electronic Thesis and Dissertation Repository

Musculoskeletal injuries can severely inhibit performance of activities of daily living. In order to regain function, rehabilitation is often required. Assistive devices for use in rehabilitation are an avenue explored to increase arm mobility by guiding therapeutic exercises or assisting with motion. Electromyography (EMG), which are the muscle activity signals, may be able to provide an intuitive interface between the patient and the device if appropriate classification models allow smart systems to relate these signals to the desired device motion.

Unfortunately, there is a gap in the accuracy of pattern recognition models classifying motion in constrained laboratory environments, and large ...


Development Of Image-Based Surgical Planning Software For Bone-Conduction Implants, Carlos D. Salgado Aug 2018

Development Of Image-Based Surgical Planning Software For Bone-Conduction Implants, Carlos D. Salgado

Electronic Thesis and Dissertation Repository

The BONEBRIDGE bone-conduction device is used to treat conductive and mixed hearing losses. The size of its floating mass transducer (FMT) can preclude implantation in certain anatomies, necessitating comprehensive surgical planning. Current techniques are time consuming and difficult to transfer to the operating room. The objective of this thesis was to develop software for calculating skull thickness to the dura mater to find locations for the FMT and to the first air cells which guarantee sufficient bone for the implant screws to grasp. Temporal bone computed tomography (CT) images were segmented and processed and custom Matlab code was written to ...


Biohydrogen Production From Synthetic Lignocellulosic Hydrolysates: Acclimatization And Inhibition, Basem Mikhaeil Fawzy Haroun Aug 2018

Biohydrogen Production From Synthetic Lignocellulosic Hydrolysates: Acclimatization And Inhibition, Basem Mikhaeil Fawzy Haroun

Electronic Thesis and Dissertation Repository

The growing concerns regarding climate change, population growth, depletion of fossil fuel, and pollution arising from the combustion of petroleum-based fuel can be identified as the most important factors driving the urgent need for environmentally friendly renewable energy. Among all the recognized alternatives to gasoline-based fuel, hydrogen is not only considered as a clean energy but also it has a high energy content of 142 kJ/g which is almost three times higher compared to other fossil fuels. Only water and heat are the by-products of hydrogen combustion. Dark fermentative hydrogen production is a feasible option in which inexpensive, low-grade ...


Microinjection Molding Of Carbon Filled Polymer Composites, Shengtai Zhou Aug 2018

Microinjection Molding Of Carbon Filled Polymer Composites, Shengtai Zhou

Electronic Thesis and Dissertation Repository

There has been increasing demand for microparts in the areas of electronics, automotive, biomedical and micro-electro-mechanical systems. Microinjection molding (μIM) is becoming an important technology to fabricate miniature products or components to satisfy the ever-increasing needs of the above industries. Polymers and polymeric composites are ubiquitously adopted as molding materials due to their weight advantage, good processability and excellent resistance to corrosion.

Earlier studies have been primarily focused on the μIM of unfilled thermoplastics; however, microparts with multi-functionalities, such as electrical, thermal and mechanical properties are always accommodated by using multi-functional filler loaded polymer composites. Recently, μIM of carbon nanotubes ...


Development Of An Emg-Based Muscle Health Model For Elbow Trauma Patients, Emma Farago Aug 2018

Development Of An Emg-Based Muscle Health Model For Elbow Trauma Patients, Emma Farago

Electronic Thesis and Dissertation Repository

Musculoskeletal (MSK) conditions are a leading cause of pain and disability worldwide. Rehabilitation is critical for recovery from these conditions and for the prevention of long-term disability. Robot-assisted therapy has been demonstrated to provide improvements to stroke rehabilitation in terms of efficiency and patient adherence. However, there are no wearable robot-assisted solutions for patients with MSK injuries. One of the limiting factors is the lack of appropriate models that allow the use of biosignals as an interface input. Furthermore, there are no models to discern the health of MSK patients as they progress through their therapy.

This thesis describes the ...


Electrokinetically-Enhanced Emplacement Of Lactate In A Chlorinated Solvent Contaminated Clay Site To Promote Bioremediation, Ainsley M. Inglis Aug 2018

Electrokinetically-Enhanced Emplacement Of Lactate In A Chlorinated Solvent Contaminated Clay Site To Promote Bioremediation, Ainsley M. Inglis

Electronic Thesis and Dissertation Repository

Bioremediation through the injection of electron donors and bacterial cultures is effective at treating chlorinated solvent contamination but faces limitations in low permeability zones where the injected amendments cannot be delivered successfully. Using electrokinetics in combination with bioremediation to enhance the delivery of amendments was tested at a chlorinated solvent contaminated field site, where lactate was injected into clay under a direct current. Advection at locations with higher hydraulic conductivities contributed to lactate transport and dilution of aqueous chlorinated solvents. There was evidence of successful delivery of lactate by electromigration (EM) in all monitoring locations with EM lactate transport rates ...


Signal Identification In Discrete-Time Based On Internal-Model-Principle, Jie Chen Aug 2018

Signal Identification In Discrete-Time Based On Internal-Model-Principle, Jie Chen

Electronic Thesis and Dissertation Repository

This work presents an implementation of a signal identification algorithm which is based on the internal model principle. By using several internal models in feedback with a tuning function, this algorithm can decompose a signal into narrow-band signals and identify the frequencies, amplitudes and relative phases. A desired band-pass filter response can be achieved by selecting appropriate coefficients of the controllers and tuning functions, which can reject the noise and improve the performance. To achieve a result with fast transient characteristics, this system is then modified by adding a low-pass filter. This work is based on the previous work in ...


Automatic Image Classification For Planetary Exploration, Lei Shu Aug 2018

Automatic Image Classification For Planetary Exploration, Lei Shu

Electronic Thesis and Dissertation Repository

Autonomous techniques in the context of planetary exploration can maximize scientific return and reduce the need for human involvement. This thesis work studies two main problems in planetary exploration: rock image classification and hyperspectral image classification. Since rock textural images are usually inhomogeneous and manually hand-crafting features is not always reliable, we propose an unsupervised feature learning method to autonomously learn the feature representation for rock images. The proposed feature method is flexible and can outperform manually selected features. In order to take advantage of the unlabelled rock images, we also propose self-taught learning technique to learn the feature representation ...


Insecs: An Intelligent Network Security System, Nadun Rajasinghe Aug 2018

Insecs: An Intelligent Network Security System, Nadun Rajasinghe

Electronic Thesis and Dissertation Repository

There are new challenges in network security, introduced by the nature of modern networks like IoT systems, Cloud systems, and other distributed systems. System resource limitations in IoT, delays in processing the large stream of data from Cloud and distributed system, incapability to handle multi-step attacks due to delay in updates, limited datasets used for Intrusion Detection System (IDS) training which impacts the system performance are some of the pressing issues. To address these challenges, the author proposes Intelligent Network Security Systems, a framework that can handle these issues and also be as accurate as a commercial grade IDS. The ...


Anaerobic Digestion Of Aqueous Pyrolysis Condensate, Connie Wen Aug 2018

Anaerobic Digestion Of Aqueous Pyrolysis Condensate, Connie Wen

Electronic Thesis and Dissertation Repository

Lignocellulosic material can be subjected to pyrolysis to yield pyrolysis liquid, biochar, and gas. The pyrolysis liquid resulting from the condensation of vapours can be separated into a rich organic condensate and an acidic “aqueous pyrolysis condensate” (APC) which may be considered a waste. The target of this research is subjecting APC to anaerobic digestion to produce biogas that can be energy purposed, and to reduce the organic load of APC to acceptable levels for possible disposal. From this study, it was found that without any treatment, the inoculum requires 50 to 60 days of adaptation period to reduce the ...


Hydrodynamics Of A Gas-Driven Gas-Liquid-Solid Spouted Bed, Jia Meng Aug 2018

Hydrodynamics Of A Gas-Driven Gas-Liquid-Solid Spouted Bed, Jia Meng

Electronic Thesis and Dissertation Repository

A novel cylindrical gas-driven gas-liquid-solid spouted bed was developed in this project, which has a high potential to be used for a biological wastewater treatment process. Solids motion, flow regimes, and regime transitions in this system were studied. With increasing gas velocity, four regimes were identified, including: fixed bed, semi spouted bed, full spouted bed and internal circulating fluidized bed. The respective gas velocities for the transitions between the four regimes were experimentally identified and termed as minimum spouting velocity, full spouting velocity and minimum circulating velocity. A new “basketing” method was adopted to measure the minimum spouting velocity while ...