Mechanical Engineering Commons^™

Development Of A Novel Handheld Device For Active Compensation Of Physiological Tremor, Abhijit Saxena

Electronic Thesis and Dissertation Repository

In microsurgery, the human hand imposes certain limitations in accurately positioning the tip of a device such as scalpel. Any errors in the motion of the hand make microsurgical procedures difficult and involuntary motions such as hand tremors can make some procedures significantly difficult to perform. This is particularly true in the case of vitreoretinal microsurgery. The most familiar source of involuntary motion is physiological tremor. Real-time compensation of tremor is, therefore, necessary to assist surgeons to precisely position and manipulate the tool-tip to accurately perform a microsurgery. In this thesis, a novel handheld device (AID) is described for compensation …

Characterization Of Solar Roadways Via Computational And Experimental Investigations, Rajesh Kanna Selvaraju

Electronic Thesis and Dissertation Repository

Efficiency of traditional solar panels is known to be very low and hence necessitates the use of extensive open spaces for producing solar-based electric power. In solar roadways concept, open spaces such as roads, parking lots, bicycle lanes, footpaths are proposed to be utilized. An in-depth quantitative feasibility study for implementing solar roadways in Canada is carried out considering the total available surfaces, solar panel efficiency and effects of fast moving shades. The load carrying capability of commercially available materials for the solar panel top cover is studied in an effort to examine the current as well as near-future implementation …

Improved Non-Linear Solution Of Dip Coating Flow, Omar Bin Yusuf

Electronic Thesis and Dissertation Repository

A thin layer of film is developed on the surface of a substrate in the dip coating process where the substrate is initially immersed into the coating fluid and then withdrawn continuously from the coating fluid bath. In this study a two dimensional flow of the thin film for a Newtonian fluid is examined theoretically by dividing the film into three separate regions. A general formulation is developed for a thin film flow, which then simplifies for each region upon considering appropriate assumptions to each region. The influence of inertia and surface tension in the presence of gravity is investigated …

Preoperative Planning Of Robotics-Assisted Minimally Invasive Cardiac Surgery Under Uncertainty, Hamidreza Azimian

Electronic Thesis and Dissertation Repository

In this thesis, a computational framework for patient-specific preoperative planning of Robotics-Assisted Minimally Invasive Cardiac Surgery (RAMICS) is developed. It is expected that preoperative planning of RAMICS will improve the rate of success by considering robot kinematics, patient-specific thoracic anatomy, and procedure-specific intraoperative conditions. Given the significant anatomical features localized in the preoperative computed tomography images of a patient's thorax, port locations and robot orientations (with respect to the patient's body coordinate frame) are determined to optimize characteristics such as dexterity, reachability, tool approach angles and maneuverability. In this thesis, two approaches for preoperative planning of RAMICS are proposed that …

Numerical Simulation Of Catalytic Ozone Decomposition Reaction In A Gas-Solids Circulating Fluidized Bed Riser, Lei Kong

Electronic Thesis and Dissertation Repository

Computational fluid dynamics (CFD) modeling of catalytic ozone decomposition reaction in a circulating fluidized bed (CFB) riser using iron impregnated FCC particles as catalyst is carried out. The catalytic reaction is defined as a one-step reaction with an empirical coefficient. Eularian-Eularian method with kinetic theory of granular flow is used to solve the gas-solids two-phase flow in the CFB riser. The simulation results are compared with experimental data, with the reaction rate modified using an empirical coefficient to provide better simulation results than the original reaction rate. Moreover, the particle size has great effects on the reaction rate. Studies on …

Biomechanical Modeling For Lung Tumor Motion Prediction During Brachytherapy And Radiotherapy, Zahra Shirzadi

Electronic Thesis and Dissertation Repository

A novel technique is proposed to develop a biomechanical model for estimating lung’s tumor position as a function of respiration cycle time. Continuous tumor motion is a major challenge in lung cancer treatment techniques where the tumor needs to be targeted; e.g. in external beam radiotherapy and brachytherapy. If not accounted for, this motion leads to areas of radiation over and/or under dosage for normal tissue and tumors. In this thesis, biomechanical models were developed for lung tumor motion predication in two distinct cases of lung brachytherapy and lung external beam radiotherapy. The lung and other relevant surrounding organs geometries, …

An Automated Lab-On-A-Cd System For Parallel Whole Blood Analyses, Tingjie Li

Electronic Thesis and Dissertation Repository

Medical diagnostics plays a critical role in human healthcare. Blood analysis is one of the most common clinical diagnostic assays. Biomedical engineers have been developing portable and inexpensive diagnostic tools that enable fast and accurate tests for individuals who have limited resources in places that require such field applications. The emergence of Lab-on-a-CD technology provides a compact centrifugal platform for high throughput blood analysis in point-of-care (POC) diagnostics. The objective of this thesis work is to develop a Lab-on-a-CD system for parallel quantitative detection of blood contents.

Blood separation is a key step in blood analysis. By integrating out-of-plane microvalves …

Structure-Property Relationships Of Magnesium Alloys, Pouya Sharifi

Electronic Thesis and Dissertation Repository

First, I would like to acknowledge Meridian Technologies Inc., for their contributions in the materials, equipment and facilities that made this work possible.

Second, this project was also partly funded By AUTO21 Network of Centers of Excellence, an automotive research and development program focusing on issues relating to the automobile in the 21^st century. AUTO21, member of the Networks of Centers of Excellence of Canada program is funded by the Natrual Science and Engineering Research Council (NSERCT), the Social Science and Humanities Research Council (SSHRC) and multiple industries.

Third, I would like to thank the invaluable inputs and guidance …

Numerical Modelling Of Transport In Complex Porous Media: Metal Foams To The Human Lung, Christopher T. Degroot

Electronic Thesis and Dissertation Repository

Transport in porous media has many practical applications in science and engineering. This work focuses on the development of numerical methods for analyzing porous media flows and uses two major applications, metal foams and the human lung, to demonstrate the capabilities of the methods. Both of these systems involve complex pore geometries and typically involve porous domains of complex shape. Such geometric complexities make the characterization of the relevant effective properties of the porous medium as well as the solution of the governing equations in conjugate fluid-porous domains challenging. In porous domains, there are typically too many individual pores to …

Consistent Density Scanning And Information Extraction From Point Clouds Of Building Interiors, Kuldeep Kumar Sareen

Electronic Thesis and Dissertation Repository

Over the last decade, 3D range scanning systems have improved considerably enabling the designers to capture large and complex domains such as building interiors. The captured point cloud is processed to extract specific Building Information Models, where the main research challenge is to simultaneously handle huge and cohesive point clouds representing multiple objects, occluded features and vast geometric diversity. These domain characteristics increase the data complexities and thus make it difficult to extract accurate information models from the captured point clouds.

The research work presented in this thesis improves the information extraction pipeline with the development of novel algorithms for …

Investigation Of In-Vivo Hindfoot And Orthotic Interactions Using Bi-Planar X-Ray Fluoroscopy, Kristen M. Bushey

Electronic Thesis and Dissertation Repository

A markerless RSA method was used to determine the effect of orthotics on the normal, pes planus and pes cavus populations. Computed tomography (CT) was used to create bone models that were imported into the virtual environment. Joint coordinate systems were developed to measure kinematic changes in the hindfoot during weight-bearing gait and quiet standing. The objectives of this thesis were to (1) implement a fluoroscopy-based markerless RSA system on the foot, (2) determine the effect of various orthotics at midstance of fully weight-bearing dynamic gait, and (3) determine the effect of orthotics as measured using three different techniques. Every …

In-Vivo Investigation Of The Medial Longitudinal Arch Of The Foot And Orthotic Interactions Using Bi-Planar Fluoroscopy, Megan E.R. Balsdon

Electronic Thesis and Dissertation Repository

Orthotic devices are a conservative treatment for common disorders of the foot and ankle such as pes planus and pes cavus. It is thought that orthotics change the kinematics of the foot by applying forces and constraint on the plantar surface, which can act to change body biomechanics and correct for malalignment in the legs and trunk. This thesis compares the angle of the medial longitudinal arch (MLA) between three foot types: pes planus (low arch), pes cavus (high arch) and normal arch, during barefoot and shoed walking, and walking with orthotics. In-vivo bi-planar fluoroscopy was used with markerless radiostereometric …

Electrohydrodynamic Enhancement Of Heat Transfer And Mass Transport In Gaseous Media, Bulk Dielectric Liquids And Dielectric Thin Liquid Films, Seyed Reza Mahmoudi

Electronic Thesis and Dissertation Repository

Controlling transport phenomena in liquid and gaseous media through electrostatic forces has brought new important scientific and industrial applications. Although numerous EHD applications have been explored and extensively studied so far, the fast-growing technologies, mainly in the semiconductor industry, introduce new challenges and demands. These challenges require enhancement of heat transfer and mass transport in small scales (sometimes in molecular scales) to remove highly concentrated heat fluxes from reduced size devices. Electric field induced flows, or electrohydrodynamics (EHD), have shown promise in both macro and micro-scale devices.

Several existing problems in EHD heat transfer enhancements were investigated in this thesis. …

Mechanical Instability Of Thin Solid Film Structures, Masoud Noroozi

Electronic Thesis and Dissertation Repository

Instability of thin film structures as buckling and wrinkling are important issues in various fields such as skin aging, mechanics of scars, metrology of the material properties of thin layers, coating of the surfaces and etc. Similar to the buckling, highly ordered patterns of wrinkles may be developed on the film‒substrate due to compressive stresses. They may cause a failure of the system as structural damage or inappropriate operation, however once they are well understood, it is possible to control and even use them properly in various systems such as the gossamer structures in the space, stretchable electronics, eyelike digital …

Investigation Of The Use Of Micro-Mechanical Testing To Analyze The Mechanical Anisotropy Of The Zr-2.5%Nb Pressure Tube Alloy, Richard O. Oviasuyi

Electronic Thesis and Dissertation Repository

Maintaining a safe operation of nuclear power plants is the primary requirement of nuclear power generating organizations worldwide. This necessitates the use of highly effective methods for assessing the mechanical properties of reactor materials and components. This is important since all components located in a nuclear reactor core experience high levels of neutron irradiation which cause defects to be formed in the metals’ crystal structure. The density of these crystal defects increases with increasing exposure to neutrons and cause the crystalline metal to become harder and simultaneously more brittle. This change in mechanical properties is potentially detrimental to the safe …

Development Of Novel Solar Tracking And Heat Extracting Technologies, Hassan Latif Hassan

Electronic Thesis and Dissertation Repository

The global energy and water crises are looming due to the exponential population growth and the shrinking reserves of conventional fossil fuels and fresh water. The present research is aimed at the development of novel components/technologies that would lead to efficient and affordable concentrated solar thermal systems. A novel dual-axis solar tracking system has been developed, built and extensively tested on a field parabolic dish solar collector model. The tracker has two main novel components; active dual axis tracker; and load compensator. The tracker is characterized with simplicity and reliability. Two geometries of novel conical thermal receivers were designed, constructed …

On-Line Monitoring Of Engine Health Through The Analysis Of Contaminants In Engine Lubricant, Hamid R. Aghayan

Electronic Thesis and Dissertation Repository

Monitoring automobile liquids, such as engine lubricants, has received increasing attention recently mainly due to environmental and safety legislation, coat saving measures, and customer demand.

Literature review in monitoring engine lubricant condition indicates systems approach, an intellectual discipline method to address complex problem, has never been used to monitor engine performance and health through the engine sub-systems such as lubricant system. The literature review also points toward deficiency in considering lubricant as a source of information for engine performance evaluation, and lack of understanding of engine lubricant as a medium with random properties.

Engine lubricant condition reflects the state of …

An Experimental Investigation On The Flow Behaviour In A Transpired Air Collector, David Greig

Electronic Thesis and Dissertation Repository

An experimental investigation of the flow dynamics in a transpired air collector channel with a corrugated surface is presented. Particle image velocimetry (PIV) was used to obtain twodimensional velocity fields to compare the effects of surface heating on the flow for five flow rates. Mean velocity and turbulent property profiles are presented and compared. Proper orthogonal decomposition and wavenumber spectrum analyses were also conducted to investigate the underlying interactions between the turbulent structures that comprise the complex flow behaviour observed in corrugated flows. Results show that the corrugated waveform was the primary source of turbulence at all flow rates and …

Optically Driven Ph Gradient Generator Based On Self-Assembled Proton Pumps For Activating Hydrogel Microactuators, Khaled M. Al-Aribe

Electronic Thesis and Dissertation Repository

This dissertation presents a new approach for developing a biologically inspired photo-electro-chemo-mechanical microactuator by exploiting the ion pumping characteristics of bacteriorhodopsin (bR) proton pumps and the pH sensitivity of smart hydrogels. The ultimate goal of this project is to prove the viability of integrating bR monolayer into novel actuation applications using molecular level architectures. To accomplish this, the bR proton pumps are molecularly labelled, organized, and directionally immobilized on Au-coated substrate, and then integrated with pH sensitive hydrogel. When responding to an incident light beams, the internal proton pumping mechanism is mathematically modeled for quantifying the processing of the photonic …

Experimental Modal Analysis Of Micron-Scale Structures, Joel M. Book

Electronic Thesis and Dissertation Repository

Micron-scale structures, including but not limited to MEMS devices, are a class of mechanical systems with a wide range of real-world applications. One important type of dynamic properties are modal, or vibrational, characteristics, which can have great effects on performance, reliability, and useful life of a system. This makes the determination of these characteristics an important element in the design and testing of these systems. The research described in this thesis addresses important challenges in experimental modal characterization of micron-scale structures, including difficulties in: applying suitable known excitations; measuring small magnitude response motions; avoiding excessive mass loading; and dealing with …

Convection Due To Spatially Distributed Heating, Mohammad Zakir Hossain

Electronic Thesis and Dissertation Repository

Convection in an infinite horizontal slot subject to spatially distributed heating has been investigated for a wide range of Prandtl numbers. The primary flow response consists of convection in the form of rolls. When heating wave number alpha is sufficiently large the convection is found to be limited to a layer adjacent to lower wall and a uniform conductive layer emerges at upper section of the slot.

Conditions leading to the emergence of secondary convection have been identified using linear stability of the above primary convection. The secondary convection gives rise to longitudinal, or transverse, or oblique rolls; or to …

Vortex Shedding From Elongated Bluff Bodies, Zachary J. Taylor

Electronic Thesis and Dissertation Repository

As the spans of suspension bridges increase, the structures become inherently flexible. The flexibility of these structures, combined with the wind and particular aerodynamics, can lead to significant motions. From the collapse due to flutter of the Tacoma Narrows Bridge to the case of vortex-induced vibrations (VIV) of the Storebælt Bridge, it is evident that a better understanding of the aerodynamics of these geometries is necessary. The work herein is motivated by these two problems and is presented in two parts.

In the first part, the focus is on the physical mechanisms of vortex shedding. It is shown that the …

Surface Reconstruction From Unorganized Point Cloud Data Via Progressive Local Mesh Matching, Ji Ma

Electronic Thesis and Dissertation Repository

This thesis presents an integrated triangle mesh processing framework for surface reconstruction based on Delaunay triangulation. It features an innovative multi-level inheritance priority queuing mechanism for seeking and updating the optimum local manifold mesh at each data point. The proposed algorithms aim at generating a watertight triangle mesh interpolating all the input points data when all the fully matched local manifold meshes (umbrellas) are found. Compared to existing reconstruction algorithms, the proposed algorithms can automatically reconstruct watertight interpolation triangle mesh without additional hole-filling or manifold post-processing. The resulting surface can effectively recover the sharp features in the scanned physical object …

Collision Detection And Merging Of Deformable B-Spline Surfaces In Virtual Reality Environment, Harish Pungotra

Electronic Thesis and Dissertation Repository

This thesis presents a computational framework for representing, manipulating and merging rigid and deformable freeform objects in virtual reality (VR) environment. The core algorithms for collision detection, merging, and physics-based modeling used within this framework assume that all 3D deformable objects are B-spline surfaces. The interactive design tool can be represented as a B-spline surface, an implicit surface or a point, to allow the user a variety of rigid or deformable tools. The collision detection system utilizes the fact that the blending matrices used to discretize the B-spline surface are independent of the position of the control points and, therefore, …

Atomic Force Microscopy For Better Probing Surface Properties At Nanoscale: Calibration, Design And Application, Yu Liu

Electronic Thesis and Dissertation Repository

To measure force by AFM with high resolution requires accurate calibration of optic – lever detection sensitivity and spring constant. On biological AFM force mode, the coupling effects of the liquid environment, spot size of laser beam and laser spot location on AFM cantilever backside, must be considered to correlate the static sensitivities from force curves in air and in liquid for calibration. An effective model has been developed first and experimentally elucidated to calibrate the static sensitivity in liquid. The proposed model eliminates inconvenience of static sensitivity calibration in liquid with possible contamination sources.

The static sensitivity based on …

Robust Initial Matching Of Free-Form Objects Represented By Point Cloud Data, Nimun A. Jahangir

Digitized Theses

No abstract provided.