Engineering Commons^™

Development Of Probabilistic Corrosion Growth Models With Applications In Integrity Management Of Pipelines, Shenwei Zhang

Electronic Thesis and Dissertation Repository

Metal-loss corrosion is a major threat to the structural integrity and safe operation of underground oil and gas pipelines worldwide. The reliability-based corrosion management program has been increasingly used in the pipeline industry, which typically includes three tasks, namely periodic high-resolution inline inspections (ILIs) to detect and size corrosion defects on a given pipeline, engineering critical assessment of the corrosion defects reported by the inspection tool and mitigation of defects. This study addresses the core involved in the reliability-based corrosion management program. First, the stochastic process in conjunction with the hierarchical Bayesian methodology is used to characterize the growth of …

Antibacterial Studies On Titania Polyurethane Nanocomposite Coatings, Koosha Azhie

Electronic Thesis and Dissertation Repository

While temporary disinfection of a surface is possible with the help of strong cleaners, tremendous interest exists for the control of microorganisms on surfaces by effective, durable antimicrobial coatings. There is a wide spectrum of potential applications for antibacterial coatings, spanning from industrial surface coatings to biomedical applications, where sterile conditions are crucial. This work examined the synthesis of the functionalized 2,2-Dimethylolpropionic acid - nanotitanium dioxide (DMPA-nTiO₂) monomer. Moreover, functionalized nanotitanium dioxide/polyurethane (nTiO₂/PU) composite coatings were prepared using the above mentioned functionalized monomer. The distribution of nTiO₂ in the polymer matrix was enhanced by monomer …

Development Of An In-Vitro Passive And Active Motion Simulator For The Investigation Of Shoulder Function And Kinematics, Joshua W. Giles

Electronic Thesis and Dissertation Repository

Injuries and degenerative diseases of the shoulder are common and may relate to the joint’s complex biomechanics, which rely primarily on soft tissues to achieve stability. Despite the prevalence of these disorders, there is little information about their effects on the biomechanics of the shoulder, and a lack of evidence with which to guide clinical practice. Insight into these disorders and their treatments can be gained through in-vitro biomechanical experiments where the achieved physiologic accuracy and repeatability directly influence their efficacy and impact.

This work’s rationale was that developing a simulator with greater physiologic accuracy and testing capabilities would improve …

Mechanism Of Dissolution Of High Valence Lead Oxides In Water Under Depleting Chlorine Conditions, Daoping Guo

Electronic Thesis and Dissertation Repository

Destabilization of lead corrosion scales present in plumbing materials used in water distribution systems results in elevated lead concentrations in drinking water. Lead release caused by changes in water chemistry (e.g., redox conditions) is often due to the destabilization of lead carbonate and oxide solid phases. Although prior studies have examined the effects of varying water chemistry on the stability of β-PbO₂ (plattnerite), β-PbO₂ stability under depleting chlorine conditions is poorly understood. In addition little is known regarding the mechanisms by which Pb₃O₄ (minium) dissolves under drinking water conditions. In this thesis, long-term batch dissolution …

Physical Simulation Of Tornado-Like Vortices, Maryam Refan

Electronic Thesis and Dissertation Repository

Scaling ratios of simulations are essential to research the effect of tornadic winds on buildings and structures, in both experimental and numerical studies. In order to determine the proper scaling, access to wind fields of simulated and full-scale tornadoes is needed. For the first time here Doppler radar tornado velocity fields are analyzed and compared to experimental tornado-like vortices data in order to establish the scaling necessary to simulate tornadoes in a physical laboratory setting.

A prototype three-dimensional wind testing chamber capable of simulating tornadoes, named Model WindEEE Dome (MWD), was designed and built. Tornado-like vortices were simulated and investigated …

A Vector-Based Approach To Virtual Machine Arrangement, Nicholas Cerilli

Electronic Thesis and Dissertation Repository

Cloud based data centres benefit from minimizing operating costs and service level agreement violations. Vector-based data centre management policies have been shown to assist with these goals. Vector-based data centre management policies arrange virtual machines in a data centre to minimize the number of hosts being used which translates to greater power efficiency and reduced costs for the data centre overall. I propose an improved vector-based virtual machine arrangement algorithm with two novel additions, namely a technique that changes what it means for a host to be balanced and a concept that excludes undesirable target hosts, thereby improving the arrangement …

Static And Seismic Performance Of Geosynthetics-Strengthened Pile Foundations, Ahmed M. Taha

Electronic Thesis and Dissertation Repository

Geosynthetic reinforcement in earth structures has been used extensively over the last two decades. Extensive research has been carried out to investigate solutions to enhance the lateral stability of pile foundations. This research is motivated by the need to install piles in sites characterized by soft subsurface soil conditions, and often times, in seismic active areas. This research work explores an innovative use of geosynthetics to enhance the lateral performance of pile foundations. The static and seismic soil-structure-interaction behaviors of geosynthetics-reinforced pile foundation systems were evaluated using a series of reduced scale physical model tests performed on a shaking table …

Control Of Wind Energy Conversion Systems For Large-Scale Integration With The Power System, Omid Alizadeh

Electronic Thesis and Dissertation Repository

This thesis is mainly focused on (i) mathematical modeling and real power control of a direct-drive wind energy conversion system (WECS) that employs a high-pole permanent-magnet synchronous generator (PMSG), and (ii) the contribution of the WECS to the frequency regulation process in a host power system. In the first part, a strategy is proposed for real power control of the WECS, which augments the maximum power-point tracking (MPPT) feature of modern WECSs. The proposed strategy is based on rapid torque control, rather than the (slow) pitch-angle control. Moreover, a supplementary damping scheme is presented and tuned for the proposed power …

Control Of Cooperative Haptics-Enabled Teleoperation Systems With Application To Minimally Invasive Surgery, Amir Takhmar

Electronic Thesis and Dissertation Repository

Robot-Assisted Minimally Invasive Surgical (RAMIS) systems frequently have a structure of cooperative teleoperator systems where multiple master-slave pairs are used to collaboratively execute a task. Although multiple studies indicate that haptic feedback improves the realism of tool-tissue interaction to the surgeon and leads to better performance for surgical procedures, current telesurgical systems typically do not provide force feedback, mainly because of the inherent stability issues. The research presented in this thesis is directed towards the development of control algorithms for force reflecting cooperative surgical teleoperator systems with improved stability and transparency characteristics. In the case of cooperative force reflecting teleoperation …

Behaviour Of Reinforced Concrete Conical Tanks Under Hydrostatic Loading, Tareq M. Azabi

Electronic Thesis and Dissertation Repository

Reinforced concrete conical tanks are used in municipalities and industrial applications as liquid containing vessels. Such tanks can be ground supported tanks or elevated on a supporting shaft. Although most design codes provide guidelines for rectangular and cylindrical tanks, no guidance is provided in such codes for conical tanks. Therefore, this thesis is motivated to study the behaviour and design of this type of tanks. In the current study, the accuracy of a design approach based on the provisions of Portland Cement Association (PCA-CCTWP) code for cylindrical tanks combined with an equivalent cylindrical approach provided by the American Water Works …

Surface Functionalization And Bioconjugation Of Nanoparticles For Biomedical Applications, Longyan Chen

Electronic Thesis and Dissertation Repository

Colloidal inorganic nanoparticles (NPs) have been attracting considerable interest in biomedicine, from drug and gene delivery to imaging, sensing and diagnostics. It is essential to modify the surface of nanoparticles to have enhanced biocompatibility and functionality for the in vitro and in vivo applications, especially in delivering locally and recognizing biomolecules. Herein, the goal of this research work is to develop advanced NPs with well-tailored surface functionalities and/or bio-functionality for the applications in cell tracking and analytes detection.

In the first project, quantum dots incorporating with gelatin nanoparticles (QDs-GNPs) have been developed for bioimaging applications. Two different approaches have been …

An Accurate Offline Phasor Estimation Technique For Fault Location In Series Compensated Lines, Rubeena Rubeena

Electronic Thesis and Dissertation Repository

In series compensated transmission lines, current and voltage signals measured by the line protection system include considerable sub-synchronous frequency components (SSFCs) which are not sufficiently damped within a typical fault clearing time of line protection system. This does not allow accurate phasor estimation and thereby phasor-based fault location. This paper presents an accurate algorithm which effectively filters out the unwanted frequency components and noise to perform accurate phasor estimation for fault location in series compensated transmission lines. Phasor estimation of a theoretical signal is first evaluated using the proposed method, Direct-Prony analysis and 4-cycle discrete Fourier transform algorithm. Then, various …

Shear Capacity Of Reinforced Concrete Beams At Elevated Temperatures, Mohamed Diab

Electronic Thesis and Dissertation Repository

Fire safety is an important design aspect that ensures structural integrity of a Reinforced Concrete (RC) building during fire events. As new codes are moving from prescriptive methods to performance-based methods, design engineers are in need of rational design tools to assess the capacity of RC elements during a fire event. Previous research work focused on the flexural and axial capacities of concrete elements exposed to fire. Research addressing the shear capacity of concrete elements exposed to fire is limited in the literature.

An analytical method to predict the shear capacity of RC beams exposed to elevated temperatures is proposed. …

Algorithms To Improve Performance Of Wide Area Measurement Systems Of Electric Power Systems, Sarasij Das

Electronic Thesis and Dissertation Repository

Power system operation has become increasingly complex due to high load growth and increasing market pressure. The occurrence of major blackouts in many power systems around the world has necessitated the use of synchrophasor based Wide Area Measurement Systems (WAMS) for grid monitoring. Synchrophasor technology is comparatively new in the area of power systems. Phasor measurement units (PMUs) and phasor data concentrators (PDCs) are new to the substations and control centers. Even though PMUs have been installed in many power grids, the number of installed PMUs is still low with respect to the number of buses or lines. Currently, WAMS …

Brain Tumor Segmentation With Minimal User Assistance, Liqun Liu

Electronic Thesis and Dissertation Repository

In this thesis, we propose a brain tumor segmentation system that requires only 4 clicks from users to specify a tight bounding box that completely contains the tumor.

We convert the segmentation problem to an energy minimization problem. We utilize the basic energy function that combines intensity appearance and boundary smoothness. Global and local appearance models are experimented and compared in our work.

The basic energy function does not assume any shape prior and thus leads to unrealistic shapes. We take the advantage of the fact that most of the tumors are approximately convex in shape and incorporate the star …

Numerical Simulation Of Liquid-Solid Circulating Fluidized Beds, Abbas Dadashi

Electronic Thesis and Dissertation Repository

Liquid-solid circulating fluidized bed (LSCFB) reactors are obtaining extensive attraction in the extraction process of functional proteins from industrial broth. A typical LSCFB is comprised of a riser, a downcomer, a liquid-solid separator, a top solids-return pipe and a bottom solids-return pipe. In light of the literature review conducted in this research, a detailed modeling of the protein extraction using an LSCFB ion-exchange system requires a microscopic study including hydrodynamic field, mass transfer and kinetics reactions.

A computational fluid dynamics (CFD) model was developed to simulate the hydrodynamics of the two phase flow in an LSCFB riser. The model is …

Structural And Durability Performance Of Precast Segmental Tunnel Linings, Safeer Abbas

Electronic Thesis and Dissertation Repository

The use of precast concrete tunnel linings (PCTLs) has been escalating due to its efficient and economical installation process compared to that of normal cast in-situ lining practice. Normally, PCTL segments are designed for 100 years of service life. However, tunnel structures often suffer premature degradation primarily due to reinforcement corrosion, which requires costly repair and maintenance. Hence, addressing and solving such durability-sustainability dilemma of tunnels is a must. The main aim of this dissertation is to evaluate the structural and durability performance of full-scale conventional reinforced concrete (RC) PCTL segments in comparison to steel fibre-reinforced concrete (SFRC). Moreover, the …

Hybrid Data Storage Framework For The Biometrics Domain, Abhinav Tiwari

Electronic Thesis and Dissertation Repository

Biometric based authentication is one of the most popular techniques adopted in large-scale identity matching systems due to its robustness in access control. In recent years, the number of enrolments has increased significantly posing serious issues towards the performance and scalability of these systems. In addition, the use of multiple modalities (such as face, iris and fingerprint) is further increasing the issues related to scalability. This research work focuses on the development of a new Hybrid Data Storage Framework (HDSF) that would improve scalability and performance of biometric authentication systems (BAS). In this framework, the scalability issue is addressed by …

Effects Of Surface Topographies On Heat And Fluid Flows, Hadi Vafadar Moradi

Electronic Thesis and Dissertation Repository

Responses of annular and planar flows to the introduction of grooves on the bounding surfaces have been analyzed. The required spectral algorithms based on the Fourier and Chebyshev expansions have been developed. The difficulties associated with the irregularities of the physical domain have been overcome using either the immersed boundary conditions (IBC) concept or the domain transformation method (DT).

Steady flows in annuli bounded by walls with longitudinal grooves have been studied. Analysis of pressure losses showed that the groove-induced changes can be represented as a superposition of a pressure drop due to a change in the average position of …

Removal And Recovery Of Heavy Metals By Nickel Smelter Slag, Maame Kyeiwaa Addai

Electronic Thesis and Dissertation Repository

The research was performed to assess the potential of nickel smelter slag, an industrial waste, as an adsorbent in the removal of heavy metals from solution. Results from batch studies on the effect of pH, metal-slag contact time, particle size, competition by other ions and slag dose were used to estimate the optimum adsorption conditions of the slag as an adsorbent for Cu, Pb, Cd, Ni and Zn. Adsorption of Cu and Pb were akin to the pseudo second order kinetic model and followed the Langmuir adsorption isotherm model. The calculated k₂ values were 0.18 mg g^-1min …

Image Fusion And Axial Labeling Of The Spine, Brandon Miles

Electronic Thesis and Dissertation Repository

In order to improve radiological diagnosis of back pain and spine disease, two new algorithms have been developed to aid the 75% of Canadians who will suffer from back pain in a given year. With the associated medical imaging required for many of these patients, there is a potential for improvement in both patient care and healthcare economics by increasing the accuracy and efficiency of spine diagnosis. A real-time spine image fusion system and an automatic vertebra/disc labeling system have been developed to address this. Both magnetic resonance (MR) images and computed tomography (CT) images are often acquired for patients. …