Theses

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  • 3-D modeling and simulation of crystal growth of GE₀.₉₈ Si₀.₀₂ under the influence of various gravity levels, G-jitter and rotating magnetic field using traveling solvent method
    3-D modeling and simulation of crystal growth of GE₀.₉₈ Si₀.₀₂ under the influence of various gravity levels, G-jitter and rotating magnetic field using traveling solvent method
    A three-dimensional numerical simulation was conducted to study the effect of a rotating magnetic (RMF) field on the fluid flow, heat transfer and mass transfer in the presence of various gravity levels by utilizing the traveling solvent method (TSM). The presence of the RMF suppressed the buoyancy convection in the GE₀.₉₈ Si₀.₀₂ solution zone in order to get homogeneity with a flat growth interface. It was found that the intensity of the flow at the centre of the crucible decreased at a faster rate compared to the flow near the walls when increasing magnetic field intensity is combined with a certain rotational speed. This behavior created a stable and uniform silicon distribution in the horizontal plane near the growth interface in the terrestrial condition. Different magnetic field intensities for different rotational speeds were examined in both terrestrial and micro-gravity conditions. The effects of residual acceleration, known as G-jitter, on board the International Space Station and European Space Orbiter were also investigated.
    3-DOF Longitudinal Flight Simulation Modeling And Design Using MATLAB/SIMULINK
    3-DOF Longitudinal Flight Simulation Modeling And Design Using MATLAB/SIMULINK
    Flight simulators are widely used in aerospace industry for multiple purposes. This paper highlights the importance of engineering flight simulators and presents a 3 degrees-of-freedom longitudinal flight simulation model that can be adopted to simulate aircraft behaviour for engineering analysis. A brief overview of aircraft design process is presented with reference to flight simulation procedure. A special emphasis is placed on Massachusetts Institute of Technology's Athena Vortex Lattice program that can be used to calculate aerodynamic characteristics for a given geometric configuration. The paper explains modeling of aerodynamics and thrust blocks and shows how they can be linked with equations of motion block to build a comprehensive flight simulation model. Matlab script that linearizes and trims equations of motion is also discussed and key stability results are explained in detail. Simulation test cases are also presented. Several recommendations are made at the end of the paper on the potential use of simulators and also on ways of improving the simulation model.
    3.3V Transmitter Using 1.8V Transistors In A Cascode Configuration
    3.3V Transmitter Using 1.8V Transistors In A Cascode Configuration
    A voltage-mode transmitter using a 1.8V-to-3.3V levelshifter and cascoded output buffer is proposed. 1.8V TSMC 65nm transistors are used. The design is targeted to meet JEDEC Interface Standard for Nominal 3 V/3.3 V Supply Digital Integrated Circuits DC Specifications as well as an AC transmission rate of 200 MHz on a 30 cm 50Ω board trace terminated with a 4 pF capacitive load. Overstress voltages will not be exceeded in order to avoid device failure due to breaching Gate Oxide Integrity, Hot Carrier Injection, or Negative Bias Temperature Instability.
    35% Carbon Dioxide Reactivity In A Bulimia Nervosa Sample
    35% Carbon Dioxide Reactivity In A Bulimia Nervosa Sample
    This study extended research on the specificity of the effects of the carbon dioxide (CO₂) challenge by examining panic reactivity in participants with bulimia nervosa (BN) (n=15) compared to those without bulimia nervosa (n=31). All participants completed self-report measures assessing state and trait anxiety, depression, anxiety sensitivity (AS), distress tolerance (DT), discomfort intolerance (DI), and eating disorder features. They subsequently breathed two vital capacity inhalations; room air and 35% CO₂-enriched air. Reactivity to room air was not different between groups. However, participants with BN displayed greater reactivity to CO₂ compared to the participants with BN. AS, DI, and DT could not be tested as potential mediators in the association between diagnostic group and reactivity because these constructs were not associated with reactivity. Eating disorder features and frequency of binges and purges were also not associated with reactivity. Detailed implications and suggestions for further research are discussed.
    360-­Degree Video Journalism: an analysis of the different angles of modern technology and news reporting
    360-­Degree Video Journalism: an analysis of the different angles of modern technology and news reporting
    This paper will analyse and consider 360-­degree videos in the context of previous new technologies and how they changed processes for journalism. Referencing previous research literature, news articles, case studies and my personal experience using 360-­degree videos as a videojournalist, this paper will serve as a conceptual review in order to better understand new considerations that might have to be taken when considering 360-­degree videos for daily news production. Moreover, this paper will review the introduction of liveblogs and Facebook Live, and how each has fundamentally changed journalism. By doing so, this conceptual review will hope to identify unique challenges and successes that 360-­degree video journalism might have for the reporter from a technical, ethical and storytelling point of view.
    3D Reconstruction of Exposed Underground Utilities Using Photogrammetric Methods
    3D Reconstruction of Exposed Underground Utilities Using Photogrammetric Methods
    This thesis addresses the topic of three-dimensional (3D) reconstruction of exposed underground utilities using photogrammetric methods. Research on this topic is mainly motivated by the need for improved information on the location of underground utilities and, thus, to provide reliable information for the management of buried assets. In this thesis, a system of photogrammetric software programs is developed for 3D reconstruction of underground utilities. Camera calibration programs are used for computing interior elements and lens distortion coefficients of digital cameras and saving them in a lookup table (LUT). The accuracy of calibrated image coordinates satisfies the photogrammetric processing demand. An automatic image point detection method is proposed and achieved in these programs. External orientation programs are used for calculating exterior elements of the digital images. Based on geographic information system (GIS) and global positioning system (GPS) techniques, a new ground control points (GCPs) collection method is proposed and implemented in these programs. A 3D reconstruction program provides corresponding functions to obtain and edit 3D information of underground utilities. Epipolar lines are employed as an assisting tool that helps operators easily find homologous points from different digital images. The study results indicate that photogrammetric methods for reconstructing 3D information of underground utilities are effective and low cost.
    3D Shape Estimation Of Tendon-Driven Catheters Using Ultrasound Imaging
    3D Shape Estimation Of Tendon-Driven Catheters Using Ultrasound Imaging
    Active cable/tendon-driven catheters are becoming an established part of the minimally invasive surgical procedures. Therefore, there has been growing interest in literature in estimating the shape of their distal end especially using clinical ultrasound (US) imaging systems. The purpose of this thesis is to use a B-mode US imaging system to design time-efficient, accurate and robust algorithm for 3D shape estimation of tendon-driven catheters. Kalman filter (KF), Adaptive Kalman filter (AKF) and Particle filter (PF) algorithms were developed for this purpose. First, they were applied to a series of simulated US B-mode images where AKF provided the best estimate (error: 0.2 ± 0.1 mm). Second, they were applied to a series of experimentally obtained US B-mode images. Calibration procedures were carried out to calibrate these US images in the experiment’s workspace. The PF was shown to provide the best 3D shape estimate (error: 8.6 ± 0.1 mm). However, since almost the same accuracy could be achieved with AKF in ten times less computational time, AKF was concluded to be the best method, in terms of accuracy and efficiency, to estimate the 3D shape of tendon-driven catheters.
    3D modelling of industrial piping systems using digital photogrammetry and laser scanning
    3D modelling of industrial piping systems using digital photogrammetry and laser scanning
    Industrial metrology is one of the fastest growing areas in advanced technologies, such as electronics and optics, computation speed, and it has been increased in recent years. There are several tools used in industrial metrology, such as total stations, digital photogrammetry, and laser scanning. Close range digital photogrammetry has been implemented for an industrial piping system in terms of installation, inspection, and replacement. Laser scanning is also used for industrial measurements to generate 3D coordinates points. In order to develop a 3D modelling strategy, this thesis focuses on the development, selection and design of photogrammetric procedures and project specific targets. This thesis also explores image-acquiring sensors such as digital cameras and laser scanners in terms of their capabilities and advantages. Based on experimental setup accuracy, measurements of piping systems are compared for applications of two different sensors.Effects of different surface materials are examined in laser scanning applications and several different types of materials are used for acquiring point clouds data. Measurement of pipes' diameters and residual analyses are conducted with different surface materials, which are used for industrial pipes. Significant improvement in laser scanning data acquisition is examined in terms of data quality both quantitatively and qualitatively during the residual analyses.
    3D printed phantom to mimic dynamic softening of cervix during pre-labour
    3D printed phantom to mimic dynamic softening of cervix during pre-labour
    It is thought that through the development of more realistic training models for midwives and obstetricians it may be possible to reduce the overuse of labour induction. To this end we demonstrate a method for creating pneumatically-controlled phantom cervixes using thermoplastic elastomer, filled with a granular material. The maximum spring constant of the phantom cervix was measured to be 10.5 N/m at -20 kPa deflated air (vacuum) and the minimum spring constant measured was 5.3 N/m at 20 kPa inflated air. The true stress measured on these elastomeric phantom cervixes indicated a maximum stress of 133 kPa and a minimum stress of 94 kPa at 0.15 strain. Discrimination and threshold tests demonstrated that people can distinguish between the hard and soft states of the phantom. Future work will focus on increasing the softness of these devices.
    60 seasons : a conversation around the future of food
    60 seasons : a conversation around the future of food
    The current state of food production in the Western world is leading to the devastation of our land, soil, and air. industrial farms are contributing not just to poor human health, but to the ever increasing depletion of our natural esources, a reduction in the biodiversity of plants and animals and in the sustainability of the planet. 60 Seasons – A Conversation around the Future of Food aims to stimulate the dialogue around healthy and sustainable means of food production by depicting the efforts of two small groups within Northumberland County, Ontario. Their aim is to bring sustainable farming methods to their community, while expanding the discourse around environmentally sound food production and providing healthy food choices to those in need.
    A  Comparative Study Of The Mechanical Performace of PLA Specimens Manufactured Using Compression Molding and 3D Printing
    A Comparative Study Of The Mechanical Performace of PLA Specimens Manufactured Using Compression Molding and 3D Printing
    Compression molding is known to be one of the most cost-effective method to manufacture Polymer-based composite parts including pure thermoplastics, e.g. PolyLactic Acid (PLA). One of the current research questions is how a new innovative technology like 3D printing compares to compression molding in terms of mechanical performance of final parts. This study aims at comparing the mechanical performance of dog-bone tensile coupons manufacturing using compression molding and 3D printing. The compression molding manufacturing process parameters are optimized to obtain maximum mechanical properties. This study investigates the effect of each parameter, including processing temperature, processing pressure, and dwell times on tensile modulus and strength of a pure PLA part coupon per ASTM D638-14. The entire study is conducted using a total of 54 specimens manufactured in a set of 9 batches for various combination of process parameters per Design Of Experiment (DOE). Optimum process parameters for PLA 3D printing have been obtained from previous studies and are used for comparison purposes. A comparison of mechanical performance of ASTM D638 coupons manufactured using optimum compression molding and 3D printing techniques is performed.
    A 1.2 V, 8-bit, 100 MHz pipelined analog-to-digital converter
    A 1.2 V, 8-bit, 100 MHz pipelined analog-to-digital converter
    A 1.2 V, 8 bit, 100 MSample/Sec Pipeline Analog-to-Digital Converter is designed in 0.18-μm standard CMOS technology. An emphasis was placed on observing the low voltage and low power design. The architecture of this ADC is 1 bit/stage pipelined configuration.With above specifications the designed ADC can be applicable for DVI flat-panel display; Giga bit Ethernet on copper, RGB to LCD converter and cable modem. This designed ADC can achieve SNDR 56dB in 100 MHz sampling frequency with 8 bit resolution. Total power dissipation is 40.6mW and INL is around 1 LSB and the maximum swing of the input is 1 Volt peak to peak which is almost rail-to-rail situation. The core area of the ADC excluding pads is around 0.25mm 2 .