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Liquid Prebreakdown Phenomena And The Associated Involvement Of Electrohydrodynamic Processes., Diana Hua. Ren
Liquid Prebreakdown Phenomena And The Associated Involvement Of Electrohydrodynamic Processes., Diana Hua. Ren
Electronic Theses and Dissertations
Six dielectric liquids have been investigated for the confirmation of the EHD theory of current response to the application of ramped high voltage by using a prebreakdown technique. The conduction current and displacement current were measured and studied individually. Upon plotting conduction current as well as displacement current on a log V -log I scale, two linear portions of the current characteristics were observed in the high stress regime. Thus two separate regimes of the characteristic were found exhibiting current transport in direct proportion to a simple power of the applied voltage, $\rm I\propto V\sp{s}$ (or $\rm I \propto V\sp{g}$ …
Wear Regimes And Transitions In Ceramic Particulate-Reinforced Aluminum Alloys., Jie. Zhang
Wear Regimes And Transitions In Ceramic Particulate-Reinforced Aluminum Alloys., Jie. Zhang
Electronic Theses and Dissertations
The purpose of this work was to study the dry sliding wear properties of aluminum matrix composites A356Al-SiC, 6061Al-Al$\sb2$O$\sb3$, 2014Al-SiC, with 0-20 pct. volume fraction reinforcement. Experiments were performed with a load range of 1 to 450 N and a sliding velocity range of 0.1 to 5.0 m/s. Two types of counterface materials, namely SAE52100 bearing steel and mullite, were used. Three different wear rate regimes were observed in the composites. These were: (i) regime I (ultra mild wear regime), which occurred at low loads and low sliding velocities, where ceramic particles acted as load bearing elements. In this region …
A Screening Method For Life-Cycle Inventory Analysis For Industrial Material., Athelstan King Yun. Choi
A Screening Method For Life-Cycle Inventory Analysis For Industrial Material., Athelstan King Yun. Choi
Electronic Theses and Dissertations
In this thesis, a screening method for inventory analysis for industrial material is presented. Life-cycle assessment is defined as a concept or methodology to holistically evaluate the environmental effects of a product, process or activity, by analyzing the entire life-cycle of the particular subject. It consists of three complementary components: (1) inventory analysis, the identification and quantification of energy and resource uses and environmental releases to air, water, and land; (2) impact analysis, the technical qualitative and quantitative characterization and assessment of the consequences on the environment; and (3) improvement analysis, the evaluation and implementation of opportunities to reduce environmental …
A New Particle Image Velocimetry Technique For Three-Dimensional Flows., Satya. Kurada
A New Particle Image Velocimetry Technique For Three-Dimensional Flows., Satya. Kurada
Electronic Theses and Dissertations
A technique has been developed whereby the three-dimensional (3-D) motion of particles in a fluid flow is automatically analyzed. A CCD (Charge Coupled Device) camera was used in conjunction with a tri-split lens and a mirror arrangement to simultaneously record stereo and orthogonal views of the particle-seeded flow field. A two-stage calibration algorithm has been implemented to determine the coefficients for each view separately. The images were digitally enhanced to aid in separating the particles from the background. Algorithms were developed to match individual particles in the stereo and orthogonal views. The positional information obtained from the stereo views was …
Numerical Analysis Of Two Phase Fluid Flow And Heat Transfer In A Condenser., Atish. Bokil
Numerical Analysis Of Two Phase Fluid Flow And Heat Transfer In A Condenser., Atish. Bokil
Electronic Theses and Dissertations
A quasi-three-dimensional algorithm is developed to simulate two-phase fluid flow and heat transfer in the shell side of power plant condensers. The simulation method developed is based on the fundamental governing conservation equations of mass and momentum for both gas and liquid phases, and the air mass fraction conservation equation. In the proposed numerical method, the condenser shell side is subdivided into a number of domains normal to the cooling water flow direction. The three-dimensional effects due to the cooling water temperature difference are taken into account by a series of two dimensional calculations, each being for one domain. A …
Elevated Temperature Wear Of An Aluminum Matrix Composite Al6061-20 Percent Aluminum(2) Oxygen(3) Intermetallic Alloy Titanium(50) Nickel(47) Iron(3)., Jugraj. Singh
Electronic Theses and Dissertations
Aluminum matrix composites, with high strength and high thermal stability, are replacing cast iron in automotive engine and brake components where temperature exceeds 200$\sp\circ$C. Intermetallic materials are designated high temperature materials and considerable progress has been made in improving their ductility. Thus two materials, representing each class of materials with potential tribological application prospects, have been selected for this work. Sliding wear of Al6061, Al6061-20%Al$\rm\sb2O\sb3$ and $\rm Ti\sb{50}Ni\sb{47}Fe\sb3$ was studied in the temperature range 25-520$\sp\circ$C against a SAE52100 steel counterface. A new wear machine was constructed to operate in the temperature range 25-1000$\sp\circ$C. Both wear rates and coefficient of friction …
Synthesis Of Multilevel Pass Transistor Logic Networks., Arunita. Jaekel
Synthesis Of Multilevel Pass Transistor Logic Networks., Arunita. Jaekel
Electronic Theses and Dissertations
Traditional design of logic circuits involves implementing a function in terms of standard logic gates. However, this type of design does not fully exploit the unique switching properties of MOSFETs, which can lead to more efficient realizations. Over the past decade there has been considerable interest in Pass Transistor Logic (PTL) circuits. PTL circuits implement a logic function as a network of NMOS transistors. They show enhanced performance over conventional logic in terms of both speed and area optimization as well as reduced power dissipation, particularly for certain classes of circuits. Existing synthesis techniques for PTL are limited to two-level …
A Backcast Methodology For Planning And Justification Of Advanced Manufacturing Technology Acquisition: A Model Of Capability Building Process., Zheng. Liu
Electronic Theses and Dissertations
Inadequacies of conventional investment justification methodologies in Advanced Manufacturing Technology (AMT) cases are well known. The inadequacies mainly stem from exclusion of qualitative and "intangible" factors when evaluating AMT investment proposals. To address the problem, a framework of AMT planning and justification is presented in this paper. The framework takes a 'backcast' approach, in which the AMT acquisition is modelled as an essential effort in a process of building manufacturing capabilities for a firm's long term competitiveness positioning. The intangible benefits associated with AMT acquisitions are explicitly considered and modelled as a set of manufacturing capability measures. Non-financial, or activity-based …
Concrete Culverts Reinforced With Glass Fibre Reinforced Plastics (Gfrp)., Atef Awad. Hanna
Concrete Culverts Reinforced With Glass Fibre Reinforced Plastics (Gfrp)., Atef Awad. Hanna
Electronic Theses and Dissertations
The use of Glass Fibre Reinforced Plastics (GFRP) in reinforced concrete culverts has been investigated as an alternative rust free material to replace the conventional steel bars. Structures reinforced with GFRP show early development of cracks followed by proportional increase in loading and deflection as a result of the reduced bending rigidity compared to members reinforced with steel rebars. The reduction in bending rigidity is desirable in buried structures due to the fact that their behaviour is governed by the soil-structure interaction in which the bending moment and shear forces are reduced in the culvert walls with the reduction of …
An Analysis Of Manual Postal Sorting And Station Design Using Electromyography., Chris Peter. Kourtis
An Analysis Of Manual Postal Sorting And Station Design Using Electromyography., Chris Peter. Kourtis
Electronic Theses and Dissertations
Twelve subjects sorted mail to discover if the mail sorting task or station design caused repetitive strain injury symptoms. Subjects performed the task at six different stations. Each station had two design components for study. Electrodes were placed on the deltoid, trapezius and infraspinatus muscles to study localised muscle fatigue, which is known to be a contributing factor to repetitive strain injuries. 54% of the male and 33% of the female trials resulted in statistical indications of muscle fatigue. There was no indication that the occurrence of indicators was due to station design. Additional analysis was performed using subjective responses …
High Speed Laser Welding Instability And Optimization., Mohammad Nasim. Uddin
High Speed Laser Welding Instability And Optimization., Mohammad Nasim. Uddin
Electronic Theses and Dissertations
Laser welding has firmly entrenched itself as an attractive manufacturing process technology in the industry. Despite its role of a viable manufacturing process, its overall efficiency is not significantly higher than other joining processes, in particular resistance welding. It is apparent that the high traverse speed of laser welding would increase the manufacturing process efficiency and productivity. One aspect of the research is to optimize process parameters for the physical performance of automotive body-in-white sheet steels joined by high speed welding. For this purpose, exploratory phases of pre-design experiments, bead-on-plate welding and optimization of welding in butt joint configurations are …
Inventory Control Considerations In Multi-Period Models Of Cellular Manufacturing Systems., Ali A. Mohamed
Inventory Control Considerations In Multi-Period Models Of Cellular Manufacturing Systems., Ali A. Mohamed
Electronic Theses and Dissertations
Recent developments in manufacturing technologies indicate that the adoption of cellular manufacturing technology has been an essential step in improving factory performance and productivity in batch manufacturing industries. For this purpose, however, additional innovative methods are needed to further reduce product cost and lead time and to enhance product quality to help increase market share and profitability. The adoption of the group technology concept allows small batch production to achieve economies similar to those of mass production while retaining the flexibility of the smaller job shop. In this research, four mathematical models of inventory control within a cellular manufacturing system …
Bicmos Implementation Of The Hierarchy For Pattern Extraction Artificial Neural Network., Kai Yiu. Hung
Bicmos Implementation Of The Hierarchy For Pattern Extraction Artificial Neural Network., Kai Yiu. Hung
Electronic Theses and Dissertations
This thesis presents the architecture and the algorithm of the Hierarchy for Pattern Extraction (HyPE) artificial neural network. The training algorithm and the recalling algorithm of the HyPE artificial neural network are rewritten into C based on a Smalltalk prototype. A switching tree minimization program is introduced that provides logic minimization capable of handling a higher transistor tree height and merges several transistor trees. The Northern Telecom 0.8$\mu$ Bipolar Complementary Metal Oxide Semiconductor (BATMOS) technology is used to implement the designs in this thesis. There are two final dynamic neuron designs that have been verified and fabricated. One neuron uses …
Computational Investigation Of Heat Transfer From An Oscillating Cylinder., Dinakara. Karanth
Computational Investigation Of Heat Transfer From An Oscillating Cylinder., Dinakara. Karanth
Electronic Theses and Dissertations
The problem of convective heat transfer from an oscillating cylinder is investigated numerically. An isothermal cylinder was forced to oscillate in the in-line and transverse directions at the mid-point lock-in frequencies with different position amplitudes of oscillation. The governing equations in a non-inertial frame of reference are simplified to obtain the vorticity, stream function and energy equations. After applying the log-polar coordinate transformation, the non-dimensional vorticity and energy equations, with appropriate boundary conditions, were solved using an alternating direction implicit method. The Poisson equation for stream function was solved iteratively using the successive over relaxation technique. The time dependent average …
Digital Network Analysis Automation., Jacky W. Y. Luk
Digital Network Analysis Automation., Jacky W. Y. Luk
Electronic Theses and Dissertations
This thesis presents the development of a software package for the purpose of analyzing digital networks. The software package consists of two graphic user interfaces, one for the signal flow graph schematic drawing, and one for the analysis of digital network. Both are written in the WATFOR-77 programming language and by using the VGAWAT graphics library. The first graphic user interface software is to draw the signal flow graph of a 1-D, 2-D, or 3-D digital network using adders, delays, and multipliers. It can extract the graphical representation of a digital network with error checking capability into a netlist for …
Fpga Implementation Of Adaptive Interference Canceler For Periodic Signal., Tony Wai Sing. Yuen
Fpga Implementation Of Adaptive Interference Canceler For Periodic Signal., Tony Wai Sing. Yuen
Electronic Theses and Dissertations
This thesis describes the design, implementation and testing of an adaptive digital interference canceler for periodic signals. This canceler uses the least mean-square (LMS) adaptive filtering technique to eliminate interference from an input signal. An advantage of the adaptive interference cancelling approach is that it requires no prior knowledge of both the signal and the interference characteristics. A digital design approach is used in this thesis because of its reliability and accuracy. The canceler implemented using a Xilinx FPGA chip. A prototype design demonstrated that the canceler was able to reduce the input interference power by about 40%.Dept. of Electrical …
Fpga Implementation Of Rns Structures., Radhaselvi. Venkatesan
Fpga Implementation Of Rns Structures., Radhaselvi. Venkatesan
Electronic Theses and Dissertations
The objective of this thesis is to investigate the applicability of Field Programmable Gate Arrays (FPGAs) for residue arithmetic applications. FPGAs are programmable devices that can be directly configured by the end user without the use of an integrated circuit fabrication facility. They offer the designer the benefits of custom hardware, eliminating high development costs and manufacturing time. The Residue Number System (RNS) has often been proposed for custom hardware implementation of high throughput DSP algorithms. Residue arithmetic operations are easier to realize using small look-up tables, and since Xilinx FPGAs use look-up tables as configurable logic blocks, they are …
Optimization Of The Reaction Conditions For Peroxidase Catalyzed Removal Of Phenolic Compounds From Industrial Wastewater., Brian J. Dantas
Optimization Of The Reaction Conditions For Peroxidase Catalyzed Removal Of Phenolic Compounds From Industrial Wastewater., Brian J. Dantas
Electronic Theses and Dissertations
Studies have shown that horseradish peroxidase (HRP), Arthromyces ramosus peroxidase (ARP), and soybean peroxidase (SBP) can effectively remove phenolic compounds from wastewater. Work has been completed at optimizing the performance conditions for at least 95% removal of phenolic compounds in a continuously stirred batch reactor using HRP, ARP, and SBP. The enzymes were evaluated in two real wastewater matrices, under high and low phenol concentrations. Phenolic wastewater was collected from a petroleum refinery, and from an iron foundry that manufactures automotive components. The refinery sample had a phenol concentration of approximately 100 mg/L (1.0 mM), while the foundry sample contained …
Oxides On Zirconium-Niobium Alloys: An Investigation Of The Different Corrosion Behaviours Of Alpha-Zirconium, Beta-Zirconium And Beta-Niobium Phases., Fang. Wang
Electronic Theses and Dissertations
Three single phase alloys namely $\alpha$-Zr, $\beta$-Zr and $\beta$-Nb (with compositions of 0.59wt% Nb, 18.2wt% Nb and 95.2wt% Nb respectively) were made using, an arc-furnace. The alloys were first homogenized by heating at 1000$\sp\circ$C for 24 h, and then subsequently subjected to corrosion tests in high temperature (300$\sp\circ$C) pressurized (8.6MPa) 0.2M and 0.05M LiOH solutions. In the 0.2M LiOH solution, for the $\alpha$-Zr alloy, corrosion followed a cubic rate law in the pre-transition period, and then changed to linear kinetics after breakaway (which is simply defined as an abrupt change (increase) in the corrosion rate). For the $\beta$-Nb alloy, corrosion …
Performance Evaluation Of An Auction Based Manufacturing System Using Generalized Stochastic Petri Nets., Shubhabrata. Biswas
Performance Evaluation Of An Auction Based Manufacturing System Using Generalized Stochastic Petri Nets., Shubhabrata. Biswas
Electronic Theses and Dissertations
Auction Based Manufacturing is a form of Heterarchical control. Such a system relies upon the intelligence of individual machining centres to allocate parts to prospective machining centres which can do the next stage of machining. This approach eliminates the requirement of a costly pre process scheduling run, which can prove to be inappropriate in the event of unforseen machine breakdowns or changes in machining capacities. One of the major drawbacks is the lack of predictability of the exact behaviour of the shop floor. It is perceived that a method by which an operator can predict the most likely behaviour of …
Fuzzy Inference Networks For Pattern Recognition., Yaling. Cai
Fuzzy Inference Networks For Pattern Recognition., Yaling. Cai
Electronic Theses and Dissertations
This dissertation presents a study of fuzzy inference networks for pattern recognition problems. In this research, fuzzy neurons are defined and five types of fuzzy neurons are introduced. Three fuzzy inference models for pattern recognition systems, min-max inference model, min-sum inference model, and min-competitive inference model, are developed. Fuzzy inference networks based on the inference models and their learning algorithms are presented. The proposed fuzzy inference networks can learn fuzzy inference rules directly from training data. Two of the proposed fuzzy inference networks, Min-Max Fuzzy Inference Network and Min-Sum Fuzzy Inference Network, are applied to pattern classification problems. These two …
Development Of Sparsely Reinforced Elastomer Sheets., Rong. Pan
Development Of Sparsely Reinforced Elastomer Sheets., Rong. Pan
Electronic Theses and Dissertations
Presently most road and railway vehicles designed to haul toxic or flammable liquids are built with a single shell tank construction. The transportation of hazardous liquids poses a problem if the vehicle hauling the liquid is involved in an accident. Loss of liquid can happen if the tank integrity is compromised. The current work is an attempt to develop a lightweight, relatively inexpensive, sparsely reinforced elastomer liner material to incorporate inside the containers, to contain leakage should the outer shell fail. The general design methodology is thus Fail-Safe Design. If this were designed properly to be an inexpensive easily replaceable …
Simultaneous Part Family And Machine Cell Formations In Cellular Manufacturing Systems: An Analytical And Algorithmic Approach., A. Alper. Ozdemir
Simultaneous Part Family And Machine Cell Formations In Cellular Manufacturing Systems: An Analytical And Algorithmic Approach., A. Alper. Ozdemir
Electronic Theses and Dissertations
Increased level of global competition and rapid changes in consumers' tastes have forced the companies to reorganize their manufacturing operations, in a way that they can produce large variety of products, in small quantities, at high quality and at a low competitive price. Cellular Manufacturing Systems have been identified as the key in achieving these objectives. In this research, mathematical programming models are developed for single and multi period planning horizons, respectively. The objective of the models is to minimize the total cost function associated with the design of cellular manufacturing systems, while minimizing exceptional part types and obtaining a …
Static And Dynamic Responses Of Simply Supported And Continuous Skew Composite Bridges., Tarek Ibrahim. Ebeido
Static And Dynamic Responses Of Simply Supported And Continuous Skew Composite Bridges., Tarek Ibrahim. Ebeido
Electronic Theses and Dissertations
The load distribution factor concept allows the design engineer to consider the longitudinal and transverse effects of wheel loads as two separate phenomena and thus simplifying the analysis and design of the bridge. North American codes of practice do not provide the design engineer with sufficient guidance regarding elastic load distribution factors for skew composite bridges. These codes of practice also require a check to be made on the strength of the sections of the bridge at the ultimate limit state, but they specify the use of elastic load distribution factors for the evaluation of the design forces at the …