Engineering Commons^™

Investigation Of Bio-Hydrogen Production Optimization From Synthetic And Real Wastes Using Pure And Mixed Cultures, Noha El-Sayed Nasr

Electronic Thesis and Dissertation Repository

Dark fermentative H₂ production is an important route to renewable energy as it is based on a known technology and can utilize a wide range of available waste streams as substrate. However, more research is required to overcome the technical barriers to practical application. The aim of this study is to investigate different scenarios towards the optimization of fermentative H₂ production from synthetic and real wastes using pure and mixed cultures. Lignocellulosic biomass, i.e. pretreated corn cobs and poplar wood hydrolysate were evaluated for H₂ production using mixed anaerobic cultures and yields of 141 and 169 mL …

Photoactive Properties Of Nanostructured Titania Modified Polyurethanes, Chao Chen

Electronic Thesis and Dissertation Repository

In order to enhance both the photoactivity and physical/mechanical properties of titania/polyurethane (PU) nanocomposites, in-situ polymerization and film casting were investigated. Both self-degrading PU foams and self-cleaning PU coatings were prepared. Functional monomers were prepared usingDMPA (2,2-dimethylolpropionic acid) functionalized anatse TiO₂ and P25 for integration into polyurethane foam with a "grafting-from" synthetic method. This technique was found to successfully reduce the agglomeration effect of titania nanoparticles inside the foams. In addition, the photodegradation rate was enhanced by > 120% over unmodified foam at an optimized loading of 3wt% DMPA functionalized anatase TiO₂. The presence of DMPA functionalized P25 …

Study Of The Dynamics And Cost Analysis Of The Biogenerator, Tariq Abou Jarboua

Electronic Thesis and Dissertation Repository

The BioGenerator is a promising energy storage solution that can be integrated with renewable power sources (i.e. wind and solar) to compensate the intermittent shortage of the renewable power sources and deliver a comprehensive power package. A trickling-bed bioreactor was considered to be used in the BioGenerator as an alternative to the initially studied ”air-lift” type bioreactor. Trickling-bed bioreactor is well known for its low power consumption for oxygen transfer. Dynamic study was conducted on lab scale trickling-bed bioreactor to investigate the effect of the ferrous iron feed interruption on the iron biooxidation rate. The study showed that the iron …

Effective Boronizing Process For Age Hardened Inconel 718, Aria Khalili

Electronic Thesis and Dissertation Repository

Boronizing or boriding is a technique to mitigate wear damage in industrial valves made of age-hardenable Inconel^® 718 which is a nickel-based superalloy. Boriding involves immersing the part in a patented boron-based compound and heating over 800 ^oC.

Boriding combined with aging has a detrimental thermal effect and was the subject of this investigation. The effects on hardness, wear and grain size, of boriding and aging separately, subsequently, and simultaneously, were investigated to observe the microstructure and mechanical properties.

The results show that boriding has negligible effect on the grain size and the hardness of the substrate. Besides, …

Basic Science To Clinical Research: Segmentation Of Ultrasound And Modelling In Clinical Informatics, Ali K. Hamou

Electronic Thesis and Dissertation Repository

The world of basic science is a world of minutia; it boils down to improving even a fraction of a percent over the baseline standard. It is a domain of peer reviewed fractions of seconds and the world of squeezing every last ounce of efficiency from a processor, a storage medium, or an algorithm. The field of health data is based on extracting knowledge from segments of data that may improve some clinical process or practice guideline to improve the time and quality of care. Clinical informatics and knowledge translation provide this information in order to reveal insights to …

Multi-Objective Optimization Of Industrial Ammonia Synthesis, Stanislav Ivanov

Electronic Thesis and Dissertation Repository

The thesis describes modelling and optimization work of an industrial ammonia synthesis. Author developed first-principle mathematical model of the commercial converter based on gas-solid reaction and heat transfer within the system. The model is validated with industrial data and showed satisfactory accuracy. Further, optimization study is performed in multi-objective manner to intensify ammonia production and decrease heat duty of the process. Result have revealed a potential to improve current operating condition int terms of both objectives.

Supercritical Fluid Extraction Of Valuable Chemicals: Application Of Microalgae And Pyrolysis Oil As Feedstocks, Osariemen Ogbeide

Electronic Thesis and Dissertation Repository

In this dissertation, pure and modified carbon dioxide were used as non-conventional solvents for the investigation of lutein, chlorophyll a, chlorophyll b extraction from microalgae and for caffeine extraction from the pyrolysis oil of spent coffee grounds. The use of toxic organic solvents in supercritical fluid extraction has propelled research efforts to develop new solvents that are environmentally friendly and provide faster extraction compared to conventional extraction processes. For this reason, phosphatidylethanolamine (PE), a major phospholipid consisting of 14% of the entire soybean lecithin was acetylated with acetic anhydride, providing a surfactant (N-A-PE).

Then, the synthesized N-A-PE was employed as …

Assessment Of The Non-Linear Stress-Strain Characteristics Of Poly (Vinyl Alcohol) Cryogel, Mojdeh Zakeri

Electronic Thesis and Dissertation Repository

Creation of tissue-mimicking constructs is of great importance in the field of biomedical engineering. Poly (vinyl Alcohol) (PVA) is a biomaterial capable of simulating a wide range of geometries and mechanical properties of biological tissues. It is nontoxic, biocompatible, and easy to produce. PVA can be physically crosslinked by repeated cycles of freezing and thawing. The final product of this process is called PVA cryogel (PVA-C). The mechanical properties of PVA-C can be accurately controlled by changing PVA molecular weight, PVA concentration, and number and duration of freeze/thaw cycles (FTC). In this study, the stress-strain behavior of PVA cryogel was …

Investigation Of Chitosan-Based Hydrogels As A Cell Delivery Platform For Adipose-Derived Stem/Stromal Cell Transplantation To Promote Angiogenesis In Ischemic Tissues, Jobanpreet Singh Dhillon

Electronic Thesis and Dissertation Repository

Stem cell transplantation is under investigation to stimulate angiogenesis in patients with peripheral artery disease. To develop a cell-delivery platform that enhances cell retention and function post-transplantation, the response of human adipose-derived stem/stromal cells (ASCs) encapsulated within N-methacrylate glycol chitosan (MGC) hydrogels with or without integrin-binding RGD or IKVAV motifs was explored. ASC viability was enhanced in the MGC and MGC-RGD hydrogels relative to the MGC-IKVAV group under hypoxic (2% O­₂) culture conditions, with cell spreading and higher metabolic activity noted in MGC-RGD at 14 days. Analysis of angiogenic gene expression revealed similar patterns between all hydrogel …

Metafork: A Compilation Framework For Concurrency Models Targeting Hardware Accelerators, Xiaohui Chen

Electronic Thesis and Dissertation Repository

Parallel programming is gaining ground in various domains due to the tremendous computational power that it brings; however, it also requires a substantial code crafting effort to achieve performance improvement. Unfortunately, in most cases, performance tuning has to be accomplished manually by programmers. We argue that automated tuning is necessary due to the combination of the following factors. First, code optimization is machine-dependent. That is, optimization preferred on one machine may be not suitable for another machine. Second, as the possible optimization search space increases, manually finding an optimized configuration is hard. Therefore, developing new compiler techniques for optimizing applications …

Wall Pressure Coefficients For Low- To High-Rise Buildings, Emilio S. Hong

Electronic Thesis and Dissertation Repository

Currently, the design of wall cladding and components are based on provisions provided in building codes, such as ASCE 7 for the United States. These codes provide pressure coefficients based on the tributary area, position on the building and the building category. For ASCE 7, low-rise and high-rise buildings are separated by an artificial boundary at 60 ft. (18.2 m). The reasoning for this artificial boundary is unclear. This work investigates the wall pressure coefficients for various buildings, based on aspect ratios, motivated by the large differences in design pressure coefficients for low-rise and high-rise buildings.

For this study, a …

Uncertainty Modeling In The Assessment Of Climate Change Impacts On Water Resources Management, Sohom Mandal

Electronic Thesis and Dissertation Repository

Climate change has significant impacts on water resource systems. The objective of this study is to assess climate change impacts on water resource management. The methodology includes (a) the assessment of uncertainty introduced by choice of precipitation downscaling methods; (b) uncertainty assessment and quantification of the impact of climate change on projected streamflow; and (c) uncertainty in and impact of climate change on the management of reservoirs used for hydropower production. The assessment is conducted for two future time periods (2036 to 2065 and 2066 to 2095). The study area, Campbell River basin, British Columbia, Canada, consists of three reservoirs …

Computer-Assisted Characterization Of Prostate Cancer On Magnetic Resonance Imaging, Derek J. Soetemans

Electronic Thesis and Dissertation Repository

Prostate cancer (PCa) is one of the most prevalent cancers among men. Early diagnosis can improve survival and reduce treatment costs. Current inter-radiologist variability for detection of PCa is high. The use of multi-parametric magnetic resonance imaging (mpMRI) with machine learning algorithms has been investigated both for improving PCa detection and for PCa diagnosis. Widespread clinical implementation of computer-assisted PCa lesion characterization remains elusive; critically needed is a model that is validated against a histologic reference standard that is densely sampled in an unbiased fashion. We address this using our technique for highly accurate fusion of mpMRI with whole-mount …

Advanced Signal Processing Methods For Plane-Wave Color Doppler Ultrasound Imaging, Omar Mansour

Electronic Thesis and Dissertation Repository

Conventional medical ultrasound imaging uses focused beams to scan the imaging scene line-by-line, but recently however, plane-wave imaging, in which plane-waves are used to illuminate the entire imaging scene, has been gaining popularity due its ability to achieve high frame rates, thus allowing the capture of fast dynamic events and producing continuous Doppler data. In most implementations, multiple low-resolution images from different plane wave tilt angles are coherently averaged (compounded) to form a single high-resolution image, albeit with the undesirable side effect of reducing the frame rate, and attenuating signals with high Doppler shifts.

This thesis introduces a spread-spectrum color …

Effects Of Turbulence On The Separating-Reattaching Flow Above Surface-Mounted, Three-Dimensional Bluff Bodies, Abul Fahad Akon

Electronic Thesis and Dissertation Repository

Investigations of separated and reattaching flows over three-dimensional bluff bodies in turbulent boundary layers are important because of the large aerodynamic loads that these flows cause. For example, roofs of low-rise buildings are vulnerable to this kind of wind loading. Turbulence in the upstream flow affects the pressure distributions and the mean size of separation bubbles formed on bluff body surfaces. Whereas a number of studies have focussed on two-dimensional separation bubbles and surface pressures, a comprehensive understanding of the surface pressures and the separating-reattaching flows in relation to the turbulence in the incident boundary layers for surface-mounted, three-dimensional bluff …

A Framework For Tumor Localization In Robot-Assisted Minimally Invasive Surgery, Nikita Chopra

Electronic Thesis and Dissertation Repository

Manual palpation of tissue is frequently used in open surgery, e.g., for localization of tumors and buried vessels and for tissue characterization. The overall objective of this work is to explore how tissue palpation can be performed in Robot-Assisted Minimally Invasive Surgery (RAMIS) using laparoscopic instruments conventionally used in RAMIS. This thesis presents a framework where a surgical tool is moved teleoperatively in a manner analogous to the repetitive pressing motion of a finger during manual palpation. We interpret the changes in parameters due to this motion such as the applied force and the resulting indentation depth to accurately determine …

Disinfection By-Products Formation After Coagulation Of Algal Extracellular And Intracellular Organic Matters, Tianyiru Chen

Electronic Thesis and Dissertation Repository

Algal organic matter (AOM) is found in high concentration during algal bloom season in drinking water systems, which is generally categorized into extracellular organic matter (EOM) and intracellular organic matter (IOM). These compounds are not well removed in traditional water treatment methods such as coagulation, and are the precursors of subsequent disinfection by-products (DBPs) during chlorination of water. In this study, EOM and IOM content of four different algae were quantified measuring dissolved organic carbon (DOC), UV absorbance at 254 nm and turbidity. Coagulation using alum (Al₂(SO₄)₃•16H₂O)was used to remove the algal …

Convection In Corrugated Slots, Seyed Arman Abtahi

Electronic Thesis and Dissertation Repository

This thesis consists of two parts. The first part deals with the development of proper methodology, i.e. a spectrally accurate algorithm suitable for analysis of convection problems in corrugated slots. The second part is devoted to the study of natural convection in corrugated slots.

The algorithm uses the immersed boundary conditions (IBC) concept to deal with the irregular form of the solution domain associated with the presence of corrugated plates. The field equations are discretized on a regular domain surrounding the flow domain using Fourier expansions in the horizontal direction and Chebyshev expansions in the vertical direction. The boundary conditions …

Bim Assisted Design Process Automation For Pre-Engineered Buildings (Peb), Mohammad Delavar

Electronic Thesis and Dissertation Repository

The effective adoption and implementation of Building Information Modeling (BIM) is still challenging for the construction industry. However, studies and reports show a significant increase in the rate of BIM implementation and adoption in mainstream construction activities over the last five years. In contrast, Pre-Engineered Building (PEB) construction, a specialized construction system which provides a very efficient approach for construction of primarily industrial buildings, has not seen the same uptake in BIM implementation and adoption. The thesis reviews the benefits and the main applications of BIM for the PEB industry as well as challenges of its practical implementation. To facilitate …

Microbial Repopulation Following In Situ Star Remediation, Gavin Overbeeke

Electronic Thesis and Dissertation Repository

In situ STAR (Self-sustaining Treatment for Active Remediation) is an emerging remediation technology which uses smouldering combustion to destroy nonaqueous phase liquid (NAPL) contamination in the subsurface. Since STAR smouldering travels through contaminated soils slowly (~0.5 to 5 m/day) and subjects them to high temperatures (400–1000°C), it is expected that this technology will thoroughly dry and sterilize the zones which it treats. Further, soils surrounding the treatment zone which are not smouldered will be heated, although not smouldered, by virtue of their proximity to STAR, impacting microbial communities within them. Therefore, the objectives of this work are to quantify the …

Numerical Modeling Of Tornado-Like Vortex And Its Interaction With Bluff- Bodies, Zoheb Nasir

Electronic Thesis and Dissertation Repository

The study the flow structure of tornado-like vortices and their impact over engineering structures is important due to the extent of tornado induced fatalities and damages observed each year in North America and around the world. In the present study, a numerical modeling approach inspired by the WindEEE Dome and the modified version of Ward’s Tornado Simulator has been developed. Using a full-scale numerical simulator, tornadoes of different intensities have been simulated for different swirl ratio values to study flow structures in comparison with previous studies. The effect of topographic features on the tornado-like vortex has been investigated for the …

Expert-In-The-Loop Multilateral Telerobotics For Haptics-Enabled Motor Function And Skills Development, Mahya Shahbazi

Electronic Thesis and Dissertation Repository

Among medical robotics applications are Robotics-Assisted Mirror Rehabilitation Therapy (RAMRT) and Minimally-Invasive Surgical Training (RAMIST) that extensively rely on motor function development. Haptics-enabled expert-in-the-loop motor function development for such applications is made possible through multilateral telerobotic frameworks. While several studies have validated the benefits of haptic interaction with an expert in motor learning, contradictory results have also been reported. This emphasizes the need for further in-depth studies on the nature of human motor learning through haptic guidance and interaction. The objective of this study was to design and evaluate expert-in-the-loop multilateral telerobotic frameworks with stable and human-safe control loops that …

Numerical Simulation Of Air Flow In Aeroengine Compressors, Shady Mohamed Mohamed Ali

Electronic Thesis and Dissertation Repository

The performance of an aeroengine is influenced by the performance of the compressor system. A typical compressor consists of multistage axial compressors followed by a centrifugal stage. Here, a high-speed centrifugal and an axial stage are investigated in terms of turbulence modelling, flow blockage and rotor-stator (R-S) gap using the commercial software ANSYS CFX. The curvature corrected Shear stress transport (SST-CC) model of Smirnov and Menter is investigated for the first time in a high-speed centrifugal stage in terms of curvature and rotation effects. The SST-CC predictions are compared with the standard SST, Speziale, Sarkar, and Gatski Reynolds stress model …

Modifications To Acm Classifier And Fine Powder Coating For Plastic Components, Xinping Zhu

Electronic Thesis and Dissertation Repository

Powder coating is a dry coating technology, which has several advantages over conventional liquid coatings. However, wider applications were limited by its inferior surface finish and increased film thickness. Making powder finer (fine powder technology) can provide much better surface appearance and smaller film thickness comparable to liquid coating, but it’s much more difficult to produce fine powder products with narrow particle size distributions than coarse powder. Another issue that restricts the applications is its electrostatic spraying method, which limits the applications mainly to be with conductive substrates, like metals.

In this study, to ensure a narrow particle size distribution …

Contextual Model-Based Collaborative Filtering For Recommender Systems, Dennis E. Bachmann

Electronic Thesis and Dissertation Repository

Recommender systems have dramatically changed the way we consume content. Internet applications rely on these systems to help users navigate among the ever-increasing number of choices available. However, most current systems ignore that user preferences can change according to context, resulting in recommendations that do not fit user interests. Context-aware models have been proposed to address this issue, but these models have problems of their own. The ever-increasing speed at which data are generated presents a scalability challenge for single-model approaches. Moreover, the complexity of these models prevents small players from adapting and implementing contextual models that meet their needs. …

Histological Quantification In Temporal Lobe Epilepsy, Charlotte Anne Blinston

Electronic Thesis and Dissertation Repository

Approximately 30 percent of epilepsy patients suffer from refractory temporal lobe epilepsy which is commonly treated with resection of the epileptogenic tissue. However, surgical treatment presents many challenges in locating the epileptogenic focus and thus not all patients become seizure-free following surgery. Advances in techniques can lead to improved localization of the epileptogenic zone and may be validated by correlating MRI with neuropathology of the excised cortical tissue. Focal cortical dysplasias are a neuropathological group of cortical malformations that are often found in cases of refractory epilepsy, however, they are subtle and difficult to quantify. The purpose of this research …

Effect Of Land Use And Low Impact Development Measures On Urban Flood Hazard: A Case Study In The Black Creek Watershed, Tommy Kokas

Electronic Thesis and Dissertation Repository

The number of flooding events in Canadian urban environments continues to increase, causing major environmental, economic and social consequences. This research uses the Black Creek watershed, located in southern Ontario, to investigate the impacts of urbanization on flood hazard and evaluate the effectiveness of various low impact development practices at reducing this hazard. A land use analysis indicates extensive urban growth between the periods 1949 and 2015, with extremely high imperviousness percentages existing today in the majority of the watershed. Historical hydrological simulations in PCSWMM show a significant increase in peak flows since 1949, but have now stabilized due to …

Design Of Radio-Frequency Arrays For Ultra-High Field Mri, Ian R O Connell

Electronic Thesis and Dissertation Repository

Magnetic Resonance Imaging (MRI) is an indispensable, non-invasive diagnostic tool for the assessment of disease and function. As an investigational device, MRI has found routine use in both basic science research and medicine for both human and non-human subjects.

Due to the potential increase in spatial resolution, signal-to-noise ratio (SNR), and the ability to exploit novel tissue contrasts, the main magnetic field strength of human MRI scanners has steadily increased since inception. Beginning in the early 1980’s, 0.15 T human MRI scanners have steadily risen in main magnetic field strength with ultra-high field (UHF) 8 T MRI systems deemed to …

Identification, Quantification And Removal Of Pharmaceuticals And Endocrine Disrupting Compounds From Water Using Customized Pdms Membrane, Ambareen Atisha

Electronic Thesis and Dissertation Repository

This study concentrates on the identification and quantification of three pharmaceutical compounds (ibuprofen, naproxen and diclofenac) and an endocrine disrupting compound (17α-ethinylestradiol) in wastewater effluents collected from Adelaide Wastewater Treatment Plant and Greenway Pollution Control Plant, London, ON, Canada. For sample preparation, both solid-phase extraction and liquid-liquid extraction techniques were followed and GC-FID and LC-MS were used for sample analysis. Although the target pharmaceuticals were present in the wastewater samples at concentrations in a range of 0.29-8.98 µ/L, 17α-ethinylestradiol was not detected.

For eradicating or removing the above-mentioned organic compounds from water, organic solvent nanofiltration (OSNF) membrane was used in …

Effect Of L-Ascorbic Acid And All-Trans Retinoic Acid On Smooth Muscle Cells Cultured On Pcl Scaffolds, Brandon Chaffay

Electronic Thesis and Dissertation Repository

The aim of vascular tissue engineering (VTE) is to fabricate tissues that are both mechanically and biologically competent similar to the native vessel they are intended to replace. To this end, the incorporation of sufficient extracellular matrix elastin and collagen is important. The objective of this thesis work was to evaluate the effect of two biochemical factors, l-ascorbic acid (AA) and all-trans retinoic acid (atRA), on elastin synthesis when coronary artery smooth muscle cells were cultured on 3D polycaprolactone (PCL) scaffolds. First, porous PCL scaffolds were fabricated using a solvent casting and particulate leaching approach. The effect of different …