Engineering Commons^™

Explicit Solution Of The Large Amplitude Transverse Vibrations Of A Flexible String Under Constant Tension, Ali Nikkar, Reza Taghipour, Tohid Akhlaghi

Ali Nikkar

This paper presents the analytical simulation of string with large amplitudes using the Variational Iteration Method (VIM) and Hamiltonian Approach (HA). In order to verify the precision of the presented methods, current results were compared with He’s Variational Approach and Runge-Kutta 4th order. It has been found that these methods are well suited for a range of parameters and the approximate frequencies and periodic solutions show a good agreement with other techniques. The results show that both methods can be easily extended to other nonlinear oscillations and it can be predicted that both methods can be found widely applicable ...

Study Of Nonlinear Vibration Of Euler-Bernoulli Beams By Using Analytical Approximate Techniques, Saman Bagheri, Ali Nikkar

Ali Nikkar

In this paper, nonlinear responses of a clamped-clamped buckled beam are investigated. Two efficient and easy mathematical techniques called He’s Variational Approach and Laplace Iteration Method are used to solve the governing differential equation of motion. To assess the accuracy of solutions, we compare the results with the Runge-Kutta 4th order. The results show that both methods can be easily extended to other nonlinear oscillations and it can be predicted that both methods can be found widely applicable in engineering and physics.

Flow Accelerated Corrosion In Single And Dual S-Shape Bends Under Single And Two Phase Annular Flow Conditions, Hazem Mohamed Mohamed Ahmed Mazhar

Open Access Dissertations and Theses

Flow Accelerated Corrosion (FAC) is defined as a flow enhanced mass transfer phenomenon that results in pipe wall thinning of the piping system and results in abrupt failure in some cases. FAC is controlled by the transport of corrosion species from the wall to the bulk fluid and is determined by the local distribution of the mass transfer coefficient. The overall objective of this research is to investigate the mass transfer in pipe bends arranged in single and dual S- shape configurations under single and annular two phase flow conditions. A novel wall dissolving mass transfer technique was developed to ...

Surface Analysis Of Materials For Direct Wafer Bonding, Arif Ul Alam

Open Access Dissertations and Theses

Surface preparation and its exposure to different processing conditions is a key step in heterogeneous integration of electronics, photonics, fluidics and/or mechanical components for More-than-Moore applications. Therefore, it is critical to understand how various processing and environmental conditions affect the surface properties of bonding substrates. In this thesis, the effects of oxygen reactive-ion etching (O₂ RIE) plasma followed by storage in ambient and 98% relative humidity on some key surface properties such as roughness, water contact angle, hardness, and the elemental and compositional states of three materials – silicon (Si), silicon dioxide (SiO₂) and glass – are investigated to ...

Integer Programming-Based Approaches For Sustainable Community Applications, Wendy Huang

Open Access Dissertations and Theses

Sustainability is an important consideration in municipalities, and decision-makers are often faced with making trade-offs in decisions on cost, location selection, and allocation. These decisions are often riddled with complexities and uncertainties, and a heuristic approach can become costly and inefficient. Integer programming is a branch of mathematical programming that can be applied to problems such as these and can be a helpful tool in the decision making process.

This thesis presents three papers that develop and apply integer programming-based methodologies and their applications to problems faced by many communities: urban noise, school location-allocation and municipal solid waste collection.

An ...

Purification And Synthesis Of Pegylated Protein, Xiaojiao Shang

Open Access Dissertations and Theses

PEGylation, referring to the covalent attachment of poly(ethylene glycol) or PEG to protein, has become the most established technology for improving pharmacokinetic behavior of native proteins, especially the prolongation of circulation half-life in vivo. This thesis focuses on the synthesis and purification of PEGylated proteins.

The conventional way to synthesize PEGylated proteins is in liquid phase batch reaction, which usually causes the formation of significant amount and high diversity of by-products (i.e. di-, tri-, and/or higher-PEGylated forms of a protein). Many chemical and physical ways have been explored to increase the specificity of mono-PEGylated protein. Chemical ways ...

Growth, Characterization And Simulation Of Inas Quantum Wires On Vicinal Substrates, Andrew Scullion

Open Access Dissertations and Theses

The heteroepitaxial growth of InAs self-assembled quantum wires on vicinal substrates is investigated. InGaAlAs lattice-matched to InP was first deposited onto an InP(001) substrate with and without a 0.9 degree off-cut toward the (110) direction, followed by the deposition of a strained layer of InAs. Dense InAs quantum wires were successfully grown on both nominally flat and vicinal substrates in order to observe the effect of the presence of atomic steps. The off-cut angle was chosen based on the wire spacing on a flat substrate to serve as a template for their nucleation and improve their size distribution ...

Simulating Chemical Reactions Of Glass Powder In Cement Using Silica, Calcium Hydroxide And Sodium Hydroxide, Sarah Young

Open Access Dissertations and Theses

The use of supplementary cementitious materials (SCM) decreases the environmental impact of the cement industry. SCMs are commercial by-products that possess pozzolanic properties. Recycled glass powder, classified as a SCM, when added as a cement replacement reacts with the available lime in the cement to form calcium silicate hydrate (C-S-H) products. In contrast with other SCMs, glass is siliceous and thus the reaction can also cause alkali silica reaction (ASR) which causes expansion and cracking. This study was completed in order to characterize the chemical reactions and their rate using a simplified system that mimics glass particles in hardened cement ...

Six Degree-Of-Freedom, Musculotendon Joint Stiffness: Examples With The Knee, Joshua G. A. Cashaback

Open Access Dissertations and Theses

Increased muscle stiffness helps prevent excessive movement that can lead to ligament and soft-tissue damage. There is empirical evidence suggesting that muscles are important in preventing injuries caused by excessive translational movements. Very little is known, however, on how our muscles provide translational stiffness. This thesis uses complementary theoretical (Chapters 2 and 3) and experimental (Chapter 4) techniques to address how muscles provide translational joint stiffness.

In Chapters 2 and 3, we used an elastic energy approach to successfully derive equations that quantify muscular contributions to joint stiffness. From the equations, we were able to determine how the geometric orientation ...

Probabilistic Graphical Models For Prognosis And Diagnosis Of Breast Cancer, Mahmoud Khademi

Open Access Dissertations and Theses

One in nine women is expected to be diagnosed with breast cancer during her life. In 2013, an estimated 23, 800 Canadian women will be diagnosed with breast cancer and 5, 000 will die of it. Making decisions about the treatment for a patient is difficult since it depends on various clinical features, genomic factors, and pathological and cellular classification of a tumor.

In this research, we propose a probabilistic graphical model for prognosis and diagnosis of breast cancer that can help medical doctors make better decisions about the best treatment for a patient. Probabilistic graphical models are suitable for ...

Dynamic Model Of Large Amplitude Vibration Of A Uniform Cantilever Beam Carrying An Intermediate Lumped Mass And Rotary Inertia, Ali Nikkar, Saman Bagheri, Masoud Saravi

Ali Nikkar

In this paper, a mathematical model of large amplitude vibration of a uniform cantilever beam arising in the structural engineering is proposed. Two efficient and easy mathematical techniques called variational iteration method and He’s variational approach are used to solve the governing differential equation of motion. To assess the accuracy of solutions, we compare the results with the Runge-Kutta 4th order. An excellent agreement of the approximate frequencies and periodic solutions with the numerical results and published results has been demonstrated. The results show that both methods can be easily extended to other nonlinear oscillations and it can be ...

Non-Oxidative And Oxidative Torrefaction Characterization And, Wei-Hsin Chen

Wei-Hsin Chen

No abstract provided.

Swell And Shrinkage Strain Prediction Models For Expansive Clays, Anand J. Puppala, Thammanoon Manosuthikij, Bhaskar C. S. Chittoori

Civil Engineering Faculty Publications and Presentations

A comprehensive laboratory investigation was conducted to study volume change behaviors of five different types of expansive clayey soils sampled from various regions in Texas, USA. The laboratory test results, which were presented in an earlier paper, are analyzed here to evaluate existing correlations that can be used to predict swell and shrink-related displacements in these soils. The test database is also used to develop newer and practical models for predicting volume change-related soil properties. Models developed here used soil plasticity and compaction properties as independent variables. Newer models, that rely on seasonal compaction moisture content variations in the subsoils ...

An Agent Based Model Of Bacteria In Micro-Scale Laboratory Experiments, Kameliya Zhechkova Koleva

Civil Engineering Master's Theses

The increased availability of observational and experimental techniques at the single-cell level, including automated microscopy and microfluidics, motivates the development and application of individual/agent based models (IBMs/ABMs). ABMs simulate populations of individual cells and can be used to interpret observations from these experiments and put them into broader ecological context. This paper presents an ABM of bacteria. Individual cells are represented by a spherocylinder. Processes include growth, division, biomechanical (shoving) and biochemical (quorum sensing) interaction between cells and between cells and their environment. A post-processing routine generates graphs and animations that can be compared directly to individual-based observations ...

Dynamics-Based Invariants For Video Analytics, Binlong Li

Electrical Engineering Dissertations

Cameras are ubiquitously everywhere and hold the promise of significantly changing the way we live and interact with our environment. A major roadblock to achieve this potential is the curse of dimensionality: often the actionable information is a very small fraction of a vast amount of data, which is difficult to extract in real-time. In this thesis we propose to address this issue by exploiting dynamics-based invariants as an information encapsulating paradigm. The approach is inspired by the fundamental fact that visual data comes in streams: videos are temporal sequences of frames, images are ordered sequences of rows of pixels ...

Quantifying Reinforced Concrete Bridge Deck Deterioration Using Ground Penetrating Radar, Nicole Martino

Civil Engineering Dissertations

Bridge decks are deteriorating at an alarming rate due to corrosion of the reinforcing steel, requiring billions of dollars to repair and replace them. Furthermore, the techniques used to assess the decks don't provide enough quantitative information. In recent years, ground penetrating radar (GPR) has been used to quantify deterioration by comparing the rebar reflection amplitudes to technologies serving as ground truth, because there is not an available amplitude threshold to distinguish healthy from corroded areas using only GPR. The goal of this research is to understand the relationship between GPR and deck deterioration, and develop a model to ...

Fluctuations In Transient Response Of Adsorption-Based Plasmonic Sensors, Zeljko D. Cupic

Zeljko D Cupic

The basic parameters of a sensor element defining its ultimate performance are sensitivity and intrinsic noise. In plasmonic gas sensors both are determined by refractive index changes due to adsorption and desorption (a–d) of target analyte particles to the sensor active area. In this paper we present a general model that can be simultaneously used to determine sensitivity and intrinsic noise of a plasmonic sensor both during transients and in steady-state and is valid for multi-analyte environments. The model utilizes the conventional probabilistic approach. It is derived without any assumptions about the stochastic nature of the fundamental (a–d ...

Power System Dynamic State Estimation And Load Modeling, Cem Bila

Electrical and Computer Engineering Master's Theses

State estimation which constitutes the core of the Energy Management System (EMS), plays an important role in monitoring, control and stability analysis of electric power systems. An efficient, timely and accurate state estimation is a prerequisite for a reliable operation of modern power grids.

Traditional state estimators, which are based on steady state system model, cannot capture the system dynamics very well due to the slow updating rate of SCADA systems. In mid 1980s of the 20^th century, Phasor Measurement Unit (PMU)-based Wide-Area Measurement Systems (WAMS) emerged. The introduction of this high speed measurement systems, featured with synchronous ...

Behaviour Of Hollow Core Square Reinforced Concrete Columns Wrapped With Cfrp With Different Fibre Orientations, Muhammad N. Hadi, T D. Le

Faculty of Engineering and Information Sciences - Papers

Results of testing twelve hollow core square reinforced concrete columns wrapped with Carbon fibre 33 reinforced polymer (CFRP) are presented. The effect of fibre orientation on the performance of specimens 34 under concentric and eccentric loads was investigated. Twelve specimens were divided into four groups with three 36 specimens each. The specimens in the first reference group were unwrapped, while the specimens in the 37 remaining groups were wrapped with CFRP of different wrap combinations of three fibre orientations.The specimens in each group were tested 39 under three eccentricities: 0 (concentric), 25, and 50 mm up to failure. Test ...

Experimental Convective Heat Transfer In Entrance Portion Of Rib Roughened Channels, Gidley E. Dorlus

Mechanical Engineering Master's Theses

Leading edge cooling of turbine blades is essential in the advancement of the turbine industry. There are many different methods of blade cooling, from jet impingement to film cooling to convective cooling. The present experimental investigation presented delves into the use of convective cooling along with rib-roughened walls using the steady state liquid crystal technique. There were four test sections used for this investigation, using ribs at a 45° angle on the side wall and a 90° angle on the nose portion of the test section, both relative to the incoming flow. Within each test section, 2 or 3 different ...

Variable Precision Floating Point Reciprocal, Division And Square Root For Major Fpga Vendors, Xin Fang

Electrical and Computer Engineering Master's Theses

Variable precision floating point operations have various fields of applications including scientific computing and signal processing. Field Programmable Gate Arrays (FPGAs) are a good platform to accelerate such applications because of their flexibility, low development time and cost compared to Application Specific Integrated Circuits (ASICs) and low power consumption compared to Graphics Processing Units (GPUs). Increasingly scientists are interested in variable precision floating point operations not limited to single or double precision operations implemented on FPGAs, in order to make those operations more resource efficient and more suited to their own applications.

Among those operations, the performance of reciprocal, division ...

Transient Analysis Of An Electrostatically Tunable Multiferroic Inductor, Carl Joseph Hansen

Electrical and Computer Engineering Master's Theses

This thesis examines the dynamic behavior of an electric-field tunable multiferroic inductor, a four-terminal device that is comprised of a two-terminal variable inductor with an inductance controlled by a two-terminal voltage input. Although the inductor features a wide tuning range and high quality factor, little information is available regarding the inductor's transient characteristics in response to a fast changing control voltage. Therefore, its role in certain high-speed electronic applications is currently undetermined.

To reduce the aforementioned knowledge gap, the time-varying tuning response of the multiferroic tunable inductor is explored in this thesis to establish its relevance to high-speed electronics ...

Exploration Of Hot Switching Damage And Damage Mechanisms In Mems Switch Contacts, Ryan Patrick Hennessy

Mechanical Engineering Dissertations

Ohmic contact, or contact-­type, Microelectromechanical Systems (MEMS) switches employ two separable metal electrodes as a contact. In the switch environment, the switch contact may experience either of two switching modes. Cold switching refers to the application of an electrical signal across the switch only when the contact is fully closed. On the other hand, hot switching refers to the application of a signal while the switch is being opened and closed. Compared to cold switching, hot switching leads to shorter contact lifetimes.

This work explores the effect of multi-­domain coupling on the behavior of an electrical contact, what ...

Target Localization And Tracking In A Random Access Sensor Network, Kivanc Kerse

Electrical and Computer Engineering Master's Theses

Wireless Sensor Networks (WSNs) are commonly used to monitor physical or environmental parameters such as temperature, sound, velocity, etc. Such networks find application in different areas including military, environmental, medical and industrial ones. For applications that require long term monitoring, data collection with limited resources (power, bandwidth) is a challenging problem. In addressing these challenges, we study a network architecture that relies on integrating sensing and random channel access to achieve energy efficiency. Specifically, this thesis focuses on the use of WSNs for target localization and tracking. In a random access framework, distributed sensor nodes transmit data packets to the ...

Kms States On C* - Algebras Associated To Higher-Rank Graphs, Astrid An Huef, Marcelo Laca, Iain Raeburn, Aidan Sims

Faculty of Engineering and Information Sciences - Papers

Consider a higher rank graph of rank k. Both the Cuntz-Krieger algebra and Toeplitz-Cuntz-Krieger algebra of the graph carry natural gauge actions of the torus Tk, and restricting these guage actions to one parameter subgroups of Tk gives dynamical systems involving actions of the real line. We study the KMS states of these dynamical systems. We find that for large inverse temperatures B, the simplex of KMS B states of the Toeplitz-Cuntz-Krieger algebra has dimension d one less than the number of vertices in the graph. We also show that there is a preferred dynamics for which there is a ...

Design And Control Of A 2 Degree Of Freedom Upper Limb Robotic Rehabilitation Device, Patrick Joseph Murphy

Mechanical Engineering Master's Theses

Robotic neurorehabilitation is a rapidly growing field in both research and industry. Robotics offer the ability to create less labor-intensive rehabilitation for therapists, while providing an interactive experience for patients. Robotic therapy also provides the advantage of object data collection for therapists to track patient progress; however, there is still both a clinical and market need for a low-cost, assistive hand rehabilitation system. Therefore, the comprehensive design, control, and initial testing of an actuated, assistive 2 degree of freedom hand rehabilitation system with a virtual environment is presented.

The 2 degree of freedom hand rehabilitation system, named the Navigator hand ...

Dem Simulation Of The Behaviour Of Geogrid Stabilised Ballast Fouled With Coal, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers

Geogrids are commonly used in railway construction for reinforcement and stabilisation. When railway ballast becomes fouled due to ballast breakage, infiltration of coal fines, dust and subgrade soil pumping, the reinforcement effect of geogrids decreases significantly. This paper presents results obtained from Discrete Element Method (DEM) to study the interface behaviour of coal-fouled ballast reinforced by geogrid subjected to direct shear testing. In this study, irregularly-shaped aggregates (ballast) were modelled by clumping together 10-20 spheres in appropriate sizes and positions. The geogrid was modelled by bonding a large number of small spheres together to form the desired grid geometry and ...

Coupled Hydro-Geochemical Modelling Of A Permeable Reactive Barrier For Treating Acidic Groundwater, Buddhima Indraratna, Punyama Pathirage, Kerry Rowe, Laura Banasiak

Faculty of Engineering and Information Sciences - Papers

This study focuses on coupling geochemistry with geo-hydraulics to enable time-dependent modelling of the remediation of acidic groundwater using an alkaline permeable reactive barrier (PRB). Chemical clogging due to secondary mineral precipitates reduces the porosity and hydraulic conductivity of the reactive medium. The governing equations are incorporated into commercial numerical codes, MODFLOW and RT3D. An original algorithm was developed for RT3D to simulate geochemical reactions occurring in the PRB. The results and the model predictions are in agreement, confirming that the hydraulic conductivity reduction due to mineral precipitation occurs at the start of permeation and continues until halfway through the ...

State And Input Estimation In Structural Systems, Néstor Ramón Polanco

Civil Engineering Master's Theses

The purpose of this study was to properly describe the state and input estimation problems in the context of structural dynamic systems (Chapter 1). The selected estimation techniques were the Minimum Norm Response Corrector (MIRC) and the Augmented Kalman Filter (AKF). These algorithms where selected because they are formulated under different conditions and assumptions, e.g the MIRC works on a batch (offline) formulation while the AKF works in a non-batch (online) formulation being the biggest one; others are pointed out in the description of the methods (Chapter 2). To validate these two methodologies a 2D six stories steel frame ...

Three-Dimensional-Network Li3v2(Po4) 3/C Composite As High Rate Lithium Ion Battery Cathode Material And Its Compatibility With Ionic Liquid Electrolytes, Jiantie Xu, Shulei Chou, Cuifeng Zhou, Qinfen Gu, Hua K. Liu, Shi X. Dou

Australian Institute for Innovative Materials - Papers

A high performance Li3V2(PO4)3 cathode material for lithium ion batteries was synthesized by the microwave-assisted hydrothermal method followed by a post annealing process. The synchrotron X-ray diffraction analysis results confirmed that single-phase Li3V2(PO4)3 with monoclinic structure was obtained. Scanning electron microscope and transmission electron microscope images revealed that the as-prepared Li3V 2(PO4)3 was composed of nanowires and microsized particles. Electrochemical results demonstrated that the Li 3V2(PO4)3 electrode measured at 10 C after 500 cycles can deliver discharge capacities of 85.4 mAh g-1 and 103.4 mAh g-1, with a capacity retention ...