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Submergence Effects On Local Scour., Md Rajib. Ahsan
Submergence Effects On Local Scour., Md Rajib. Ahsan
Electronic Theses and Dissertations
The study discussed herein focuses on the local scour created in a cohesionless sand bed by a plane turbulent wall jet with varying levels of submergence from 1 to 20. From the observations of 40 experiments the study reveals that the formation of unstable scour processes, which can be short and long-term in nature, depends on the water depth available above the mound apex for a given initial jet velocity. In case of stable scour process, the growth of the scour hole dimensions follows a linear relation with the logarithm of time beyond which the rate of change in the …
An Object-Oriented Analysis Technique For Developing Object-Oriented Simulations In Silk., Lia. Zannier
An Object-Oriented Analysis Technique For Developing Object-Oriented Simulations In Silk., Lia. Zannier
Electronic Theses and Dissertations
Simulation is very popular as an analysis tool for complex systems. A new paradigm shift towards object oriented simulations is hoping to make simulations even more powerful and accessible. However, in order for those not familiar with object oriented techniques to join this shift, methods must be developed for them to build object oriented simulations, until they acquire an understanding of this programming paradigm. This is an attempt to develop a procedure for just such novice model builders. This thesis begins with some background on object oriented paradigm concepts. It then provides an overview of several different object oriented analysis …
Plastic Liberation Through The Comminution Of Composite Manufactured Product Wastes, Lawrence Jekel
Plastic Liberation Through The Comminution Of Composite Manufactured Product Wastes, Lawrence Jekel
Electronic Theses and Dissertations
The automotive industry is examining alternative designs of systems and components that facilitate material recovery during the processing of end-of-life vehicles. Specifically, if materials or components can be designed to separate preferentially, then material recovery from product waste will be enhanced. Two waste concepts were examined for their practical value: (1) size distribution and the related Pi Breakage theory; and (2) the liberation of materials. Samples consisting of ABS and PVC were assembled with a variety of geometries, characteristic lengths, subcomponent configurations and fastening methods. A detailed evaluation of thermoplastic comminution found that particle size distributions fit the Gaudin size …
The Effect Of Localized Muscle Fatigue On Tibial Impact Acceleration., Janice Marie. Flynn
The Effect Of Localized Muscle Fatigue On Tibial Impact Acceleration., Janice Marie. Flynn
Electronic Theses and Dissertations
Tibial impact acceleration measured during running is known to increase with general body fatigue. The purpose of this study was to determine if localized muscle fatigue of the shank muscles would also cause an increase in peak tibial acceleration. The human pendulum system was used to control impact velocity and joint angle. There were 24 women participating in the study: 12 between the ages of 20--25, and 12 between 50--60 years. Each lay supine on the pendulum, and their unshod dominant heel was impacted into a vertical force plate with a velocity between 1--1.15 m/s, and a force approximating 1.8--2.8 …
Siphon Removal Of Cohesionless Materials., Syeed Mahbub. Ullah
Siphon Removal Of Cohesionless Materials., Syeed Mahbub. Ullah
Electronic Theses and Dissertations
This thesis discusses the removal of cohesionless sediments by siphoning. A significant part of this study involves the analysis of equilibrium scour hole dimensions under different siphon flow characteristics. Scour holes of the sediments were formed by a siphon tube of three different sizes (9.65, 13.86 and 20.4 mm) positioned vertically at different positions relative to the surface of the sand bed. A total of 174 tests were performed, where the position of the tube ranged from 101.6 mm below the original bed to 6.4 mm above it. The latter part of the study investigates the heights for critical and …
A Class Of Linear Phase Iir Digital Filters Design., Tao. Dai
A Class Of Linear Phase Iir Digital Filters Design., Tao. Dai
Electronic Theses and Dissertations
Digital IIR filters find wide applications in fields such as speech processing, image processing and noise/echo cancellation. In recent years, the design of linear phase IIR filter becomes a very hot issue of research interest. As we know, FIR filters designed to approximate a magnitude response that has a narrow transition band between the passband and the stopband usually require a large number of multipliers and they have a large delay also. Hence we prefer to IIR digital filters that have less number of multipliers than their corresponding FIR counterparts but one of disadvantages is that an IIR filter cannot …
Difficult Operations In The Multi-Dimensional Logarithmic Number System., Roberto Muscedere
Difficult Operations In The Multi-Dimensional Logarithmic Number System., Roberto Muscedere
Electronic Theses and Dissertations
The Multi-Dimensional Logarithmic Number System (MDLNS), with similar properties to the Logarithmic Number System (LNS), provides more degrees of freedom than the LNS by virtue of having two or more orthogonal bases and the ability to use multiple digits. Unlike the LNS there is no direct functional relationship between binary/floating point representation and the MDLNS representation. Traditionally look-up tables (LUTs) were used to move from the binary domain to the MDLNS domain. This method could be unrealistic for hardware implementation when large binary ranges or multiple digits were used. The lack of this direct relationship also complicated the addition and …
A Mems Acoustical Sensor Array And Associated Micropackage., Sazzadur Chowdhury
A Mems Acoustical Sensor Array And Associated Micropackage., Sazzadur Chowdhury
Electronic Theses and Dissertations
This thesis develops the design methodology and fabrication procedures for a MEMS-based square planar acoustical sensor microarray for use in a hearing instrument to improve speech intelligibility in noisy and reverberant environments. The proposed microarray offers the potential of controlled directional sensitivity with a reasonably constant beamwidth over the audio frequency range when used in conjunction with an appropriate digital signal processor. The microarray consists of nine identical square-shaped capacitive-type acoustical sensors in a 3 x 3 planar layout and has a footprint area of 4.6 x 4.6 mm2 . Each sensor has a sensitivity of 10.3 mV/Pa when biased …
0.18 Micron Cmos Ip Core Design And Methodology., Joseph Steven. Schrey
0.18 Micron Cmos Ip Core Design And Methodology., Joseph Steven. Schrey
Electronic Theses and Dissertations
When working with 0.18mum or smaller CMOS technologies, current larger technology architectures are not easily scaled and subject to short channel effects. As a result, changes in architecture and/or unconventional transistor sizing must be done. The voltage comparator that has been designed consists of (13) transistors to form the following architectures; a differential input pair, a current mirror and a rail-pulling output stage. Special transistor sizing has been used in the current mirror biasing stage to produce a constant current source for biasing of the input transistors, overcoming the problems of non-constant current and non-constant transconductance due to short channel …
Simulating The Plenoptic Camera., Arash. Razavi
Simulating The Plenoptic Camera., Arash. Razavi
Electronic Theses and Dissertations
This thesis presents the simulation of a CCD based camera called the Plenoptic Camera. Plenoptic Camera is a novel single lens camera capable of capturing 3D information of the scene and is used to find the depth of the objects. The main concept behind the design of this camera lies in the fact that light which passes through the lens of a camera is quite rich in information which regular cameras are not designed to take advantage of. The plenoptic camera keeps track of the 3D information of the light rays by distributing these rays over a two dimensional array …
Vision-Guided Multiple Planar Object Recognition And Tracking., Shahed. Shahir
Vision-Guided Multiple Planar Object Recognition And Tracking., Shahed. Shahir
Electronic Theses and Dissertations
In order to minimize the cost for any improvement or changes in manufacturing products, a flexible manufacturing system is necessary. To do so, robots should be empowered with equipment like vision sensors, which can work as human eyes for robots. A tracking vision sensor consists of a CCD camera, data acquisition, preprocessing, recognition and tracking modules. In this thesis, a design methodology for invariant recognition-based object tracking is proposed, which can potentially be used for implementation of either vision sensors or tracking vision sensors. The performance of Invariant Recognition-based object tracking to a large extent depends on the object recognition …
A Reconfigurable Digital Multiplier Architecture., Pedram. Mokrian
A Reconfigurable Digital Multiplier Architecture., Pedram. Mokrian
Electronic Theses and Dissertations
The recent growth in microprocessor performance has been a direct result of designers exploiting decreasing device feature sizes, while at the same time deepening the depth of pipelines. As transistor sizes continue to shrink, the traditional gains associated with smaller feature sizes will be degraded due to the adverse effects of wire scaling. The consequences of technology scaling on circuit performance have recently become a topic of significant importance, especially in arithmetic circuitry such as digital multipliers, which exhibit highly irregular interconnections. A digital multiplier architecture will be introduced that alleviates some of the problems associated with interconnect scaling, in …
Algorithms For Motion Estimation., Songtao. Huang
Algorithms For Motion Estimation., Songtao. Huang
Electronic Theses and Dissertations
This thesis presents several block matching techniques which are utilized for motion estimation in video coding. Among these algorithms the full search algorithm is known for its superiority in the performance over the other matching techniques; this method however requires an enormous computation costs. There are reported techniques in the literature which yield sub-optimal solutions. These are discussed in this thesis while another three efficient motion estimation algorithms for different applications are developed and presented in this thesis. The main objective of these proposed algorithms is to reduce the computation cost while maintaining the performance. Experimental results with a large …
Integrated Durability Analysis Of A Vehicle Through Virtual Simulation., Craig Wood
Integrated Durability Analysis Of A Vehicle Through Virtual Simulation., Craig Wood
Electronic Theses and Dissertations
The intent of this research is to create a high fidelity multibody dynamics model of a compact Sport Utility Vehicle (SUV) using CATIA, ADAMS and NASTRAN software suites. These software packages together are used to conduct virtual proving ground simulations. An MTS 329 series Road Test Simulator (RTS), which uses servo-hydraulic actuators to replicate vehicle proving ground is used to correlate results. The overall objective is to be able to predict component failure earlier in the design process, and to reduce the amount of time spent conducting physical durability tests. This thesis builds on research currently being conducted by many …
Analysis Of Circular Geogrid-Reinforced Soil-Steel Bridge., Andre John Kendall. Bom
Analysis Of Circular Geogrid-Reinforced Soil-Steel Bridge., Andre John Kendall. Bom
Electronic Theses and Dissertations
A finite element analysis, by means of ABAQUS, has been undertaken to study the effects of inserting geogrid layers in the soil cover of a circular soil-steel bridge with a diameter of 7.6 m. Two loads are applied to the soil-steel bridge: gravity, as well as a truck load defined by the Canadian Highway Bridge Design Code design truck. Because experimentation and design of geogrids involve the application of a strip load, it is necessary to apply a strip load at the soil surface. Therefore, the rear two axles of the truck, separated by 1.2 m, are the largest loads …
Automatic Localization Of Craniofacial Landmarks Of Cephalograms Using Artificial Neural Networks., Idris S. El-Feghi
Automatic Localization Of Craniofacial Landmarks Of Cephalograms Using Artificial Neural Networks., Idris S. El-Feghi
Electronic Theses and Dissertations
In modern orthodontic practice, a great reliance is placed on objective and systematic methods of characterizing craniofacial forms, using measurements based on a set of agreed upon points known as craniofacial landmarks. Lateral skull x-ray images are usually used in cephalometric analysis to provide quantitative measurements of the head. Accurate location of those landmarks forms the basis for what is known as cephalometric evaluation. Distance and angles among these landmarks are compared with normative values to diagnose a patient's deviations from ideal form, evaluate the craniofacial growth and measure the effect of the treatment. Because of the large variability in …
Development And Analysis Of A Prototype Car-Carrier Structure Using The Finite Element Method., Zhanbiao. Li
Development And Analysis Of A Prototype Car-Carrier Structure Using The Finite Element Method., Zhanbiao. Li
Electronic Theses and Dissertations
A very common mode for transporting vehicles over land in North America is the use of truck car-carriers. This thesis describes a computer-based modeling, simulation, and validation effort to aid in the development, testing, and design improvements of the structure of a prototype car-carrier. Car-carrier structures often crack and break during service due to fatigue stress application. In addition, the large deflections on the top decks of the trailer of a car-carrier may cause considerable damage to the carrier's structure and to the loaded vehicles due to possible collisions with the carrier as well as collisions with other loaded vehicles. …
Viscometric Properties Of Lubricating Oils In The Presence Of Pour-Point Depressants And Viscosity-Index Improvers At Different Temperature Levels., Sheila. Kashkooli
Viscometric Properties Of Lubricating Oils In The Presence Of Pour-Point Depressants And Viscosity-Index Improvers At Different Temperature Levels., Sheila. Kashkooli
Electronic Theses and Dissertations
The objective of this work is to study the effect of polymeric additives upon the viscosity of two different base stocks over the temperature range -25°C to 10°C. The two base stocks being, (i) Imperial oil's MXT-5 base stock, and (ii) Chevron oil's Group III base stock. Four different viscosity-index improvers at five concentrations were employed. The viscosity-index improvers' behavior was studied in presence of pour-point depressants. The viscosity-index improvers being: hydrogenated diene copolymer (HDP) [C95-209], dispersant olefin copolymer (DOCP) [C96-309], olefin copolymer (OCP) [C98-129], polymethylacrylate (PMA) [C93-009]. The pour-point depressants are: acryloid 154-70 and paraflow 387. Kinematic viscosities and …
High-Performance Mortar Reinforced With Short Carbon Fibers., Md. Safiuddin
High-Performance Mortar Reinforced With Short Carbon Fibers., Md. Safiuddin
Electronic Theses and Dissertations
The aim of the work reported in this thesis was to evaluate the performance of carbon fiber reinforced mortar in respect of workability, strength, impact resistance, toughness, durability, and cost-effectiveness. Laboratory experiments were carried out to investigate the properties of both fresh and hardened mortars reinforced with short carbon fibers and to optimize the mix with sufficient workability, good strength, superior impact resistance, enhanced toughness, and excellent durability at reasonable cost. Experimental investigation was carried out at the Concrete Laboratory of the University of Windsor. Five different types of mortar were taken under study including the control mortar based on …
Phoneme-Based Speech Recognition Using Self-Organizing Map., Xiaofeng. Dong
Phoneme-Based Speech Recognition Using Self-Organizing Map., Xiaofeng. Dong
Electronic Theses and Dissertations
Automatic speech recognition by machine is a challenging task for man-machine communications. Because speech waveform is nonlinear and variant, a speech recognition algorithm requires much intelligence and an ability to accommodate variations. In this thesis, a hybrid speech recognizer based on self-organizing map (SOM) and fuzzy neural network (FNN) is proposed. The SOM is used to obtain the optimal phoneme response patterns of speech signal by Viterbi search algorithm and the FNN is applied for the recognition matching of these 2D speech response patterns on the SOM to fulfill the speech recognition tasks. Experiment results show that this hybrid speech …
Speech Analysis And Synthesis Based On Arma Lattice Model., Min. Wang
Speech Analysis And Synthesis Based On Arma Lattice Model., Min. Wang
Electronic Theses and Dissertations
The research documented in this thesis presents a pitch synchronous speech analysis and synthesis system using an ARMA (auto regressive moving average) lattice filter. The LP (linear predictive) model is, by far, the most widely used speech production model in speech processing. A well-known drawback with the LP model is that it ignores the effect of the nasal cavity. The mismatch between the model and the vocal tract becomes severe for nasal sound production and leads to poor synthesized speech. The nasal tract effect can be included in the speech production model by representing the vocal tract with an ARMA …
Mems Microphone Design., James Sliepenbeek
Mems Microphone Design., James Sliepenbeek
Electronic Theses and Dissertations
This thesis presents an overview of microelectromechanical (MEMS) capacitive type microphone design for use in hearing instruments. A cohesive methodology is achieved via a mechanical equation of motion. Resulting in displacement, change in capacitance, sensitivity and pull-in voltage. All derived from one equation. From this investigation it is apparent that sensitivity is the most important factor in MEMS microphone design. The topics covered in the overview are: MEMS microphone design considerations, comparison of microphone types, signal detection methods, sources of dampening, modeling methods, sensitivity estimation, pull-in voltage estimation, bias voltage, ultimate tensile strength, design space optimization and MEMS microphone design …
Identification Of Dynamic Characteristics Of Linear Systems., Md. Mizanur Rahman
Identification Of Dynamic Characteristics Of Linear Systems., Md. Mizanur Rahman
Electronic Theses and Dissertations
Structures, built in active earthquake zones, can be subjected to damaging dynamic loading. The health monitoring process for these structures is essential. When a structure is submitted to repetitive moderate earthquake events, it is expected to accumulate certain damage. The variation of the dynamic characteristics can be an indicator of the damage extension in a structure. The procedure of evaluating the dynamic characteristics of a structure is referred to as system identification. This investigation focuses on the analysis of different techniques for identifying linear structures with available recorded responses during earthquake events. These approaches are: (i) Fourier transform approach; (ii) …
Implementation Of The Maturity Method Into Precast Concrete Applications., Alvin. Olar
Implementation Of The Maturity Method Into Precast Concrete Applications., Alvin. Olar
Electronic Theses and Dissertations
The personnel at Prestressed Systems Incorporated (PSI) suspected that use of the zero slump test cylinders to measure the compressive strength of hollowcore concrete was not reliable. If a test cylinder failed only by a chipped edge while being tested for compressive strength, it was not useful for determining the time at which the prestressing force in the tendons can be transferred into the bed of hollowcore. A more reliable method was sought to quantify the compressive strength of zero slump concrete at the time of tendon release. The method should also provide real-time information on the progress of concrete …
Electrode Wear In The Resistance Spot Welding Of Galvanized Steel Sheet., Morgan Gallagher
Electrode Wear In The Resistance Spot Welding Of Galvanized Steel Sheet., Morgan Gallagher
Electronic Theses and Dissertations
In the resistance spot welding process, copper-based electrodes both conduct current and deliver force. The resultant heat and pressure of the welding process causes wear that decreases the useable life of the electrode. The wear process is accelerated considerably when welding galvanized steel sheet as compared to bare steel sheet. Electrodes used to weld galvanized sheet experience higher temperatures, pressures, and chemical attack from the zinc coating. As a result, the electrode material softens, the electrode face enlarges, and brass alloy layers form on the electrode face. If these wear mechanisms can be circumvented, electrode life can be appreciably increased …
Dynamic Analysis Of Structures With Uncertain Properties., Sudhan Sampad. Banik
Dynamic Analysis Of Structures With Uncertain Properties., Sudhan Sampad. Banik
Electronic Theses and Dissertations
The properties of engineering structures are variable by nature. This variation affects considerably the dynamic response of structures and this is overlooked in traditional deterministic analysis. The incorporation of statistical variability of structural properties in analysis has been a topic of considerable research for the last thirty years. The determination of statistical measures of a desired response variable, such as the natural frequencies, maximum displacement, or stresses has been a primary goal of this study. The objective of this research work is to determine the quantitative effect of uncertainties on the dynamic response of a structure with uncertain parameters through …
Leachate Treatment Using Natural Systems., Ahmed. El-Gendy
Leachate Treatment Using Natural Systems., Ahmed. El-Gendy
Electronic Theses and Dissertations
Due to recent stringent environmental regulations and a high potential for soil, surface and ground water pollution, disposal of landfill leachate has become a problem in handling solid wastes from municipalities. Therefore, landfill leachate treatment is required as an essential part of the solid waste management. A wide range of high to low technologies is available for partial or full, on site treatment of municipal landfill leachates. The current research work demonstrates the potential of using floating aquatic plants, such as water hyacinth (Eichhornia crassipes) and giant salvinia (Salvinia molesta), for treatment of municipal landfill leachate. The experiments were carried …
The Addition Of Hydrogen And Oxygen To A Gasoline-Fuelled Si Engine To Enhance Combustion And Reduce Emissions., Tina. D'Andrea
The Addition Of Hydrogen And Oxygen To A Gasoline-Fuelled Si Engine To Enhance Combustion And Reduce Emissions., Tina. D'Andrea
Electronic Theses and Dissertations
Automobiles have become an essential part of our economy and provide a convenience that most have become dependent on, however they have also had a dramatic impact on our health and environment. As a result there is an incentive to find ways to more efficiently use conventional fuels and decrease emissions while alternative fuels and vehicles are being developed. This research involved studying the effects of adding small amounts of hydrogen and hydrogen and oxygen to a gasoline fuelled spark ignition (SI) engine. The hydrogen and oxygen were added in a ratio of 2:1, mimicking water electrolysis products. It was …
The Effect Of Novel Solution Treatment During The Solidification Process On The Structure And Mechanical Properties Of The W319 Alloy., Xin Chen
Electronic Theses and Dissertations
A Novel Accelerated and Continuous solution treatment (ST), which is known as the Novel Solution Treatment during the Solidification Process (NSTS), was performed on the W319 Al alloy. The metallographic analyses of the test samples showed that the NSTS process allows for the dissolution of the Cu enriched phases as well as Mg and Si based phases during a shorter period of time (between 30 and 60 minutes at a temperature between 510°C and 530°C) in comparison with the solution treatment (ST) process (over 5 hours at a temperature of 495°C) used by Nemak Windsor Aluminum Plant (WAP). The metal …
The Effect Of Turbulence On Forced Convection From A Heated Horizontal Circular Cylinder., Christopher. Sak
The Effect Of Turbulence On Forced Convection From A Heated Horizontal Circular Cylinder., Christopher. Sak
Electronic Theses and Dissertations
The effects of free stream turbulence integral length scale and turbulence intensity (root-mean-square stream-wise component of velocity fluctuation) on the rate of forced convective heat transfer from a heated horizontal circular cylinder in a cross flow of air were investigated experimentally. An internally heated 5.1 cm (2&inches;) diameter aluminium cylinder was placed horizontally in an 86 cm wide by 66 cm high (34&inches; by 26&inches;) wind tunnel. The power supplied by the internally embedded heater was kept constant in order to maintain uniform surface temperature. A perforated plate was placed at the entrance to the test section to generate the …