Engineering Commons^™

A Hybrid Visual Control Scheme To Assist The Visually Impaired With Guided Reaching Tasks, Duane Jacques

Electronic Thesis and Dissertation Repository

In recent years, numerous researchers have been working towards adapting technology developed for robotic control to use in the creation of high-technology assistive devices for the visually impaired. These types of devices have been proven to help visually impaired people live with a greater degree of confidence and independence. However, most prior work has focused primarily on a single problem from mobile robotics, namely navigation in an unknown environment. In this work we address the issue of the design and performance of an assistive device application to aid the visually-impaired with a guided reaching task. The device follows an eye-in-hand, …

Spectrum Sensing And Multiple Access Schemes For Cognitive Radio Networks, Oscar G. Filio Rodriguez

Electronic Thesis and Dissertation Repository

Increasing demands on the radio spectrum have driven wireless engineers to rethink approaches by which devices should access this natural, and arguably scarce, re- source. Cognitive Radio (CR) has arisen as a new wireless communication paradigm aimed at solving the spectrum underutilization problem. In this thesis, we explore a novel variety of techniques aimed at spectrum sensing which serves as a fundamental mechanism to find unused portions of the electromagnetic spectrum.

We present several spectrum sensing methods based on multiple antennas and evaluate their receiving operating characteristics. We study a cyclostationary feature detection technique by means of multiple cyclic frequencies. …

Modeling And Protection Of Phase Shifting Transformers, Umar Khan

Electronic Thesis and Dissertation Repository

This thesis is mainly focused on the development of (i) phase shifting transformers (PSTs) mathematical and simulation models that can be used for the short-circuit and protection studies, and (ii) new phase shifting transformers protection methods that provide more secure and sensitive solutions than the standard current differential protection.

The first part of this thesis describes and presents the modeling of the single-core standard-delta, and two-core symmetrical and asymmetrical PST for protection and short-circuit studies. The models already available for such types of PSTs have limitations and require detailed test report data from the manufacturers. However, winding test data at …

Application Of Computer Algebra In List Decoding, Muhammad Foizul Islam Chowdhury

Electronic Thesis and Dissertation Repository

The amount of data that we use in everyday life (social media, stock analysis, satellite communication etc.) are increasing day by day. As a result, the amount of data needs to be traverse through electronic media as well as to store are rapidly growing and there exist several environmental effects that can damage these important data during travelling or while in storage devices. To recover correct information from noisy data, we do use error correcting codes. The most challenging work in this area is to have a decoding algorithm that can decode the code quite fast, in addition with the …

Numerical Evaluation Of Aerodynamic Roughness Of The Built Environment And Complex Terrain, Daniel S. Abdi

Electronic Thesis and Dissertation Repository

Aerodynamic drag in the atmospheric boundary layer (ABL) is affected by the structure and density of obstacles (surface roughness) and nature of the terrain (topography). In building codes and standards, average roughness is usually determined somewhat subjectively by examination of aerial photographs. For detailed wind mapping, boundary layer wind tunnel (BLWT) testing is usually recommended. This may not be cost effective for many projects, in which case numerical studies become good alternatives. This thesis examines Computational Fluid Dynamics (CFD) for evaluation of aerodynamic roughness of the built environment and complex terrain.

The present study started from development of an in-house …

Web-Based Simulation And Training Environment For Laparoscopic Camera Calibration, Kartik Thakore

Electronic Thesis and Dissertation Repository

Endoscopic cameras are increasingly employed in image-guidance procedures, where the video images must be registered to data from other modalities. However, such cameras are susceptible to distortions, requiring calibration before images can be used for registration, tracking and 3D reconstruction. Camera calibration is learned in a laboratory setting, where configuring and adjusting the physical setup is tedious and not necessarily conducive to learning. A centralized resource that utilizes 3D interactive components needs to be available for training on camera calibration. In this project, a web-based training environment for camera calibration is implemented called SimCAM. SimCAM was developed using the Web …

Optimisation Of The Transesterification Stage Of Biodiesel Production Using Statistical Methods, Arnold Paintsil

Electronic Thesis and Dissertation Repository

The present research examines solely the transesterification stage of the biodiesel production process. Six process variables that affect the yield of biodiesel at this stage are examined using the 12 run Plackett-Burman Design. To study the effect of FFA[1] and to replicate real life situations where oil (feedstock) contain varying amounts of FFA, linoleic acid is used as FFA and intentionally added to high oleic acid canola oil containing less than 0.07% FFA. The process is catalyzed with potassium carbonate and evaluated at varying temperatures, stirring rates, reaction times and methanol oil ratios. The yields at the end of …

Study On The Surface Chemistry Behavior Of Pyrochlore During Froth Flotation, Saeed Chehreh Chelgani

Electronic Thesis and Dissertation Repository

Separation of pyrochlore from its associated minerals is typically accomplished by froth flotation. The surface chemistry of pyrochlore is similar to many of its associated non-value minerals. Therefore, understanding the surface chemical properties of the pyrochlore for selective pyrochlore flotation will potentially aid in the design of flotation strategies for optimized recovery. In this study, pyrochlore samples were collected from various points in the flotation scheme at the Niobec plant, Quebec, Canada. The SEM-EDX analysis revealed that pyrochlore from the Niobec deposit occurs as high and low iron varieties, and that recovery favours varieties with a lower Fe content. To …

Numerical And Experimental Analysis Of Retrofit System For Light-Framed Wood Structures Under Wind Loading, Ryan B. Jacklin

Electronic Thesis and Dissertation Repository

Past high speed wind events have exposed the vulnerability of the roof systems of existing light-framed wood structures to the uplift forces resulting from high speed winds, contributing greatly to economic and human loss. This research focuses on developing a retrofit system to increase the uplift capacity of these structures using numerical and experimental techniques. The proposed system provides the uplift forces an alternate load path to the ground, reducing the demand placed on the weak, nailed connections within the structure. A three-dimensional finite-element model of a roof system of full-scale wood structure has been developed. The model is compared …

Carbon-Nzvi Nanocomposites For Dechlorination Of Halogenated Hydrocarbons, Jing Cheng

Electronic Thesis and Dissertation Repository

A family of hybrid nanocarbon/nanoiron composites has been developed with the aim to carry out simultaneous adsorption and dechlorination of chlorinated hydrocarbons from aqueous solutions. Several methodologies for the synthesis of these materials are evaluated in terms of their adsorption capacities and dechlorination activities. Detailed spectroscopic and microscopy studies indicate that the adsorption ability of the carbonaceous support is greatly improved after acid oxidization, attributed to the formation of oxygenated functional groups on their surfaces. When iron nanoparticles are incorporated on the composites, the materials show a much higher trichloroethylene (TCE) removal efficiency compared to bare metallic nanoiron particles or …

Finite Element Analyses Of Single-Edge Bend Specimens For J-R Curve Development, Yifan Huang

Electronic Thesis and Dissertation Repository

The fracture toughness resistance curve such as the J-integral resistance curve (J-R curve) is widely used in the integrity assessment and strain-based design of energy pipelines with respect to planar defects (i.e. cracks). Two studies about the development of the J-R curve are carried out and reported in this thesis. In the first study, the plastic geometry factor, i.e. the η_pl factor, used to evaluate J in a J-R curve test based on the single-edge bend (SE(B)) specimen is developed based on the three-dimensional (3D) finite element analysis (FEA). The main …

Static And Seismic Soil Culvert Interaction, Osama Salem A. Abuhajar

Electronic Thesis and Dissertation Repository

Failures of box culverts under static and earthquake loads can cause significant economic loss. Therefore, it is important to investigate the soil-culvert interaction of box culverts to understand their responses to such loads. The response of buried box culverts is a complex soil-structure interaction problem, where the relative stiffness between the soil and the structure is a critical factor. Soil arching is an important aspect of the soil-culvert interaction problem, and results in the redistribution of free-field stresses due to the presence of buried structures and leads to an increase or decrease in the loading around box culverts.

A series …

Effect Of Instantaneous Load Eccentricities On The Inelastic Torsional Responses Under Bi-Directional Seismic Excitations, Xiaojing Cui

Electronic Thesis and Dissertation Repository

This study evaluated the inelastic torsional response due to instantaneous load eccentricities. The load eccentricities, which caused by the motion of the center of mass are time-dependent, even exist for two-way symmetric structures under seismic excitations. The eccentricities and bi-directional horizontal excitations can lead to the torsional motion. The study of the impacts of such a second-order effect (called A-Delta effect) on structural systems and, this effect in combination with the P-Delta effect on structural systems has not been reported in the literature.

This study is focused on the investigation of the structural responses under the A-Delta …

Fabricating Cost-Effective Nanostructures For Biomedical Applications, Erden Ertorer

Electronic Thesis and Dissertation Repository

In this thesis we described inexpensive alternatives to fabricate nanostructures on planar substrates and provided example applications to discuss the efficiency of fabricated nanostructures.

The first method we described is forming large area systematically changing multi-shape nanoscale structures on a chip by laser interference lithography. We analyzed the fabricated structures at different substrate positions with respect to exposure time, exposure angle and associated light intensity profile. We presented experimental details related to the fabrication of symmetric and biaxial periodic nanostructures on photoresist, silicon surfaces, and ion-milled glass substrates. Behavior of osteoblasts and osteoclasts on the nanostructures was investigated. These results …

Investigating Conducted Microvascular Response To Localized Oxygen Delivery In Vivo Using A Novel Micro-Delivery Approach, Nour W. Ghonaim

Electronic Thesis and Dissertation Repository

Since erythrocytes release the vasodilator adenosine triphosphate (ATP) in an oxygen (O₂) dependent manner, erythrocytes are proposed to play a central role in O₂ regulation. This ATP signaling mechanism is proposed to be most efficient in the capillaries due to the short diffusion distance to the electrically coupled endothelium which communicates directly with arterioles. We hypothesize that capillaries are able to signal upstream arterioles for changes in erythrocyte supply rate in response to changes in capillary erythrocyte O₂ saturation (SO₂)through SO₂-dependent ATP signaling. To test this hypothesis, we have developed a micro-delivery …

Nanostructured Tin-Based Anodes For Lithium Ion Batteries With X-Ray Absorption Fine Structure Studies, Dongniu Wang

Electronic Thesis and Dissertation Repository

The practical applications of lithium ion batteries are highly dependent on the choice of electrodes, where boosting the materials innovations to design and achieve high capacity, excellent cycling performance, rate capability, low-cost and safe electrode materials provide the best solution. Based on this, tin-based anodes have gained great attention due to its high theoretical capacity, low cost and nontoxic nature to environment. Nevertheless, it undergoes significant volume variation(259%)during the operation of the battery, leading to pulverization and significant capacity fade. Thus, the practical application of tin-based anodes is still quite challenging. This thesis tackles issues related to tin-based anodes. It …

Flows In Grooved Channels, Alireza Mohammadi

Electronic Thesis and Dissertation Repository

This dissertation presents the analysis of effects of two-dimensional grooves on flow responses in laminar channel flows. Straight grooves have been considered which may have an arbitrary cross-section and an arbitrary orientation with respect to the flow direction. It has been shown that the grooves effects can be split into two parts; one due to the change in the mean positions of the walls and the other due to the flow modulations created by the groove geometry. The former effect can be determined analytically, while the latter effect requires numerical modelling. Projection of groove shape onto a Fourier space creates …

Resource Allocation In Uplink Long Term Evolution, Aidin Reyhanimasoleh

Electronic Thesis and Dissertation Repository

One of the most crucial goals of future cellular systems is to minimize transmission power while increasing system performance. This master thesis work presents two channel-queue-aware scheduling schemes to allocate channels among active users in uplink LTE. Transmission power, packet delays and data rates are three of the most important criteria critically affecting the resource allocation designs. Therefore, each of these two scheduling algorithms proposes a practical method that assigns resources in such a way so as to optimally maximize data rate and minimize transmission power and packet delays while ensuring the QoS requirements. After converting the resource allocation problem …

Development Of Microfabrication Process For Micro Inductive Sensors, Xueguang Han

Electronic Thesis and Dissertation Repository

Inductive position/angle sensors are widely used in vehicles and have very bright market prospects. However, the current sensor designs often suffer from high space consuming which increases the assembly size of vehicle parts. In addition, the high emission of traditional inductive sensors can cause the interference with other electronic components. In this dissertation, a novel and reliable microfabrication process was developed to fabricate a newly designed miniaturized inductive sensor for gas pedal use. The HFSS simulation has proved that the newly developed inductive sensor could provide sufficient sensitivity to meet the sensing requirements. The performance of the sensor was well …

Automated Segmentation Of Left And Right Ventricles In Mri And Classification Of The Myocarfium Abnormalities, Cyrus (Mohammad Saleh) Nambakhsh

Electronic Thesis and Dissertation Repository

A fundamental step in diagnosis of cardiovascular diseases, automated left and right ventricle (LV and RV) segmentation in cardiac magnetic resonance images (MRI) is still acknowledged to be a difficult problem. Although algorithms for LV segmentation do exist, they require either extensive training or intensive user inputs. RV segmentation in MRI has yet to be solved and is still acknowledged a completely unsolved problem because its shape is not symmetric and circular, its deformations are complex and varies extensively over the cardiac phases, and it includes papillary muscles. In this thesis, I investigate fast detection of the LV endo- and …

Ignition Method Development And First Field Demonstration Of In Situ Smouldering Remediation, Grant C. Scholes

Electronic Thesis and Dissertation Repository

Self-sustaining Treatment for Active Remediation (STAR), a smouldering combustion-based technology for remediating sites contaminated by industrial liquids, has been extensively studied in the laboratory. The technology had not been demonstrated at a real site. Moreover, the ignition method (based on heat conduction) for the process used in the laboratory was not appropriate for field deployment and an alternative was required. This work first presents the development of a new ignition method for smouldering combustion. This ignition technique (based on heat convection) was proven effective via laboratory tests, and then applied and improved through two field tests. These field tests, conducted …

Development And Applications Of A Novel Intermittent Solids Feeder For Pyrolysis Reactors, Federico M. Berruti

Electronic Thesis and Dissertation Repository

This PhD research addresses the challenge of feeding biomass residues into fluidized bed reactors for pyrolysis, through the development of a novel intermittent solid slug feeder, both for laboratory-scale and large-scale reactors. The new feeder can successfully handle biomass residues that are either too cohesive or thermally sensitive for traditional feeders.

To optimize the novel feeder performance, a model for the pulsating solids flow was developed from experimental data collected with ideal slugs, as well as real biomass flow. The model was validated using both a laboratory-scale (< 10 kg/hr) and large-scale feeder (> 250 kg/hr). Several important variables were identified. They include the material flow …

Aging And Stabilization Of Pyrolitic Bio-Oils And Model Compounds, A. G. Manjula Taranganie Siriwardhana

Electronic Thesis and Dissertation Repository

When compared to conventional liquid fuels, bio-oil has several undesired properties such as high viscosity, high acidity, high molecular weight, instability, and phase separation upon aging. Therefore, bio-oil needs further stabilization and upgrading before it can be used as a fuel in engines. Phase separation is considered as one of the major issues because it is detrimental to any fuel application and creates problems in storage, transportation and upgrading of bio-oils. This thesis investigates the phase separation of hardwood derived bio-oil under accelerated aging conditions. Different alcohols are used as stabilizing agents and the minimum required amount of alcohol for …

Piezoelectric Transformer And Hall-Effect Based Sensing And Disturbance Monitoring Methodology For High-Voltage Power Supply Lines, Sneha Arun Lele

Electronic Thesis and Dissertation Repository

Advancements in relaying algorithms have led to an accurate and robust protection system widely used in power distribution. However, in low power sections of relaying systems, standard voltage and current measurement techniques are still used. These techniques have disadvantages like higher cost, size, electromagnetic interference, resistive losses and measurement errors and hence provide a number of opportunities for improvement and integration. We present a novel microsystem methodology to sense low-power voltage and current signals and detect disturbances in high-voltage power distribution lines. The system employs dual sensor architecture that consists of a piezoelectric transformer in combination with Hall-effect sensor, used …

Collaborative Policy-Based Autonomic Management In Iaas Clouds, Omid Mola

Electronic Thesis and Dissertation Repository

With the increasing number of "machines" (either virtual or physical) in a computing environment, it is becoming harder to monitor and manage these resources. Relying on human administrators, even with tools, is expensive and the growing complexity makes management even harder. The alternative is to look for automated approaches that can monitor and manage computing resources in real time with no human intervention. One of the approaches to this problem is policy-based autonomic management. However, in large systems having one single autonomic manager to manage everything is almost impossible. Therefore, multiple autonomic managers will be needed and these will need …

Second-Order Analysis Of Cable-Stayed Bridge Deck Slabs, Zachary Mcneil

Electronic Thesis and Dissertation Repository

Current provisions in CSA S6-06 “Canadian Highway Bridge Design Code” for computing second-order effects in slender concrete beam-columns were derived for columns in buildings, where these effects can often be neglected, so their applicability to extremely slender cable-stayed bridge decks warrants investigation. The research reported in this thesis first reviews the provisions in CSA S6-06, as well as eight equations proposed by others, for computing the flexural rigidity, EI, of slender concrete beam-columns. Methods for quantifying the rotational restraint provided at deck slab supports by steel or concrete floorbeams are presented and validated: steel floorbeams provide negligible restraint but …

Development Of Nanostructured Limpo4 (M=Fe, Mn) As Cathodes For High Performance Lithium-Ion Batteries, Jinli Yang

Electronic Thesis and Dissertation Repository

Olivine LiFePO₄ has garnered the most interest because of its environmental benignity, high safety and theoretical capacity. However, the major limitation for LiFePO₄ is the intrinsically poor electronic conductivity and ionic conductivity. The sluggish kinetics for LiFePO₄ could be overcome by reducing the size, coating with conductive carbon, or doping with isovalent ions. The decrease of the size to nanoscale could shorten the diffusion time of Li ions in LiFePO₄ during intercalation/deintercalation process, but the nano-size active material usually accompanies with low tap density. Carbon coating and carbon addition could alleviate the poor electronic conductivity. However, …

Pharmaceutical Process Modeling, Optimization, And Control, Ehsan Sheikholeslamzadeh

Electronic Thesis and Dissertation Repository

In this project, the aim was to achieve two important objectives and solve some challenges that the pharmaceutical industry is facing. It will be shown that the NRTL-SAC (Non-random Two Liquid Segment Activity Coefficient) model can best predict the solubility of different pharmaceutical and chemical components in pure and mixed solvents by comparing the results with the well-known model of the UNIFAC. The four parameters that are used in the NRTL-SAC model will be found through nonlinear parameter estimation technique. This project also covers the VLE, LLE, and VLLE phase behaviour calculations using the mentioned models to verify their applicability …

Channel Flow Behaviour During Mixed Convection At Low Reynolds Numbers, Ahmed Elatar

Electronic Thesis and Dissertation Repository

The effect of mixed convection on low Reynolds numbers flow inside a horizontal square channel heated from below have been investigated experimentally. The channel flow rate ranged from 0.0210 kg/s to 0.0525 kg/s which correspond to Reynolds numbers between 300 and 750 in the absence of heating. The channel bottom surface temperature was controlled and varied from 30 ºC to 55 ºC (Grashof number ranged between 6.37×10⁶ and 3.86×10⁷). Planer Particle Image Velocimetry (PIV) technique was used to measure two-dimensional velocity fields in the channel mid-vertical plane and two horizontal planes close to the bottom heated wall. …

Vascular Segmentation Algorithms For Generating 3d Atherosclerotic Measurements, Eranga Ukwatta

Electronic Thesis and Dissertation Repository

Atherosclerosis manifests as plaques within large arteries of the body and remains as a leading cause of mortality and morbidity in the world. Major cardiovascular events may occur in patients without known preexisting symptoms, thus it is important to monitor progression and regression of the plaque burden in the arteries for evaluating patient's response to therapy. In this dissertation, our main focus is quantification of plaque burden from the carotid and femoral arteries, which are major sites for plaque formation, and are straight forward to image noninvasively due to their superficial location. Recently, 3D measurements of plaque burden have shown …