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The Design Of An Asynchronous Bcjr/Map Convolutional Channel Decoder., Kristofer Patrick Perta
The Design Of An Asynchronous Bcjr/Map Convolutional Channel Decoder., Kristofer Patrick Perta
Electronic Theses and Dissertations
The digital design alternative to the everyday synchronous circuit design paradigm is the asynchronous model. Asynchronous circuits are also known as handshaking circuits and they may prove to be a feasible design alternative in the modern digital Very Large Scale Integration (VLSI) design environment. Asynchronous circuits and systems offer the possibility of lower system power requirements, reduced noise, elimination of clock skew and many other benefits. Channel coding is a useful means of eliminating erroneous transmission due to the communication channel's physical limits. Convolutional coding has come to the forefront of channel coding discussions due to the usefulness of turbo …
Performance Evaluation Of Hierarchical Ad Hoc Networks., Tai Yu
Performance Evaluation Of Hierarchical Ad Hoc Networks., Tai Yu
Electronic Theses and Dissertations
Ad hoc networking is one of the most challenging areas of wireless communication. Theoretical analysis and experimental results show that QoS (Quality of Service) for each node degrades rapidly while the number of nodes increases in the network. One way to solve performance degradation is to use hierarchical network architectures. In this paper, we investigate performance improvements offered by hierarchical ad hoc networks over flat (non-hierarchical or conventional) ad hoc networks for QoS parameters, namely throughput capacity, delay and power efficiency. We investigated and identified trade-offs among those QoS parameters via computer simulations carried by Network Simulator 2 of University …
A Study On Adaptive Filtering For Noise And Echo Cancellation., Danhua Jiang
A Study On Adaptive Filtering For Noise And Echo Cancellation., Danhua Jiang
Electronic Theses and Dissertations
The objective of this thesis is to investigate the adaptive filtering technique on the application of noise and echo cancellation. As a relatively new area in Digital Signal Processing (DSP), adaptive filters have gained a lot of popularity in the past several decades due to the advantages that they can deal with time-varying digital system and they do not require a priori knowledge of the statistics of the information to be processed. Adaptive filters have been successfully applied in a great many areas such as communications, speech processing, image processing, and noise/echo cancellation. Since Bernard Widrow and his colleagues introduced …
Application Of Damage Mechanics For Fatigue Life Assessment., Md. Mustaqur Rahman
Application Of Damage Mechanics For Fatigue Life Assessment., Md. Mustaqur Rahman
Electronic Theses and Dissertations
Traditional multiaxial fatigue assessment models are based on the definition of an equivalent uniaxial measurement of the stress and strain tensors in the critical region of the studied component. An equivalent uniaxial criterion is then used to assess the fatigue life. In this thesis, we study a new approach based on Continuum Damage Mechanics theory. The introduction of the Continuum Damage Mechanics (CDM) in late 1970s to model fatigue has opened a new arena of research for developing a suitable model for multiaxial fatigue. In CDM, constitutive equations are derived by using internal variables under the framework of the thermodynamics …
Hydrogen Production From Glucose By Inhibiting Hydrogenotrophic Methanogens Carbon-18 Long-Chain Fatty Acids., Praveen S. Gurukar
Hydrogen Production From Glucose By Inhibiting Hydrogenotrophic Methanogens Carbon-18 Long-Chain Fatty Acids., Praveen S. Gurukar
Electronic Theses and Dissertations
Dark fermentation is an attractive process for hydrogen (H2) production from organic substrates. Rapid conversion of H2 to other products, particularly methane, is a major hindrance to H2 accumulation and recovery from the process. Long chain fatty acids (LCFAs) namely oleic (C18:0) acid (OA) and linoleic (C18:1) acid are inhibitors of aceticlastic methanogens and are suspected inhibitors of hydrogenotrophic methanogens. However, the effect of such inhibition on increasing H2 recovery from organic substrates has not been examined. Hence, in this study, C18 LCFAs were used to increase the quantity of H2 from glucose degradation. Batch experiments were conducted at 23 …
A Framework For Ipsec Functional Architecture., Mehdi. Fahandezh
A Framework For Ipsec Functional Architecture., Mehdi. Fahandezh
Electronic Theses and Dissertations
In today's network, various stand-alone security services and/or proxies are used to provide different security services. These individual security systems implementing one single security function cannot address security needs of evolving networks that require secure protocol such as IPSec. In this paper, we provide a framework for implementing IPSec security functions in a well structured functional architecture. The proposed architecture is modular and allows for composing software applications from products commercially available and developed by different suppliers to implement the entire security requirements of IPSec protocol. In addition the proposed architecture is robust in the sense that it supports open …
Development Of An Advanced Aluminum Thermal Analysis System For The Characterization Of The 319 Aluminum Alloy Solidification Process., Todd J. Stockwell
Development Of An Advanced Aluminum Thermal Analysis System For The Characterization Of The 319 Aluminum Alloy Solidification Process., Todd J. Stockwell
Electronic Theses and Dissertations
Thermal analysis is the study of heat evolution as a molten alloy transforms to a solid. Studying the evolution of heat results in a temperature, time relationship in the form of a cooling curve. Specific characteristics of the 319-aluminum cooling curve are described and related to specific metallurgical properties. Variations in the cooling curves represent changes within the solidification of the alloy and are correlated to changes in the metallurgical properties. In the present work, an aluminum thermal analysis system (AITAS) is constructed to withstand the rigors of day to day foundry conditions. Complete automation has been introduced to reduce …
Iterative Multiuser Detection With Integrated Channel Estimation For Turbo Coded Ds-Cdma., Shuvojit Chowdhury
Iterative Multiuser Detection With Integrated Channel Estimation For Turbo Coded Ds-Cdma., Shuvojit Chowdhury
Electronic Theses and Dissertations
In present days the demand of high bandwidth and data rate in wireless communications is increasing rapidly to accommodate multimedia applications, including services such as wireless video and high-speed Internet access. In this thesis, we propose a receiver algorithm for mobile communications systems which apply CDMA (Code division multiple access) as multiple access technique. Multiuser Detection and turbo coding are the two most powerful techniques for enhancing the performance of future wireless services. The standardization of direct sequence CDMA (DS-CDMA) systems in the third generation of mobile communication system has raised the interest in exploiting the capabilities and capacity of …
Load/Displacement And Energy Absorption Performances And Improvements Of Structural Members Under Tensile And Compressive Loading Conditions., Qingwu Cheng
Electronic Theses and Dissertations
The research programs detailed in this thesis focus on the load/displacement and energy absorption performances and improvements of structural members under tensile and compressive loading conditions. A theoretical model for the prediction of energy absorption capabilities of aluminum foam filled braided stainless steel tubes under tensile loading conditions has been developed based upon the unit cell concept. Comparisons between the energy absorption predictions of the analytical model and experimental observations were found to be in good agreement for assembly lengths of approximately 400 mm. Experimental investigations were also completed for energy absorbers which function under axial compressive loading conditions. The …
Microstructural Studies Of Wear Mechanisms In Cast Aluminum Alloys., Mustafa Elmadagli
Microstructural Studies Of Wear Mechanisms In Cast Aluminum Alloys., Mustafa Elmadagli
Electronic Theses and Dissertations
The microstructural basis of wear and surface degradation mechanisms in Al-Si alloys has been investigated in order to improve the current understanding of the requirements for wear resistant aluminum alloy design. The wear behaviour of three commercial alloys namely: a sand cast A390 (Al-18.4%Si), a spray formed Al-25%Si, and a die cast 383 (Al-9.5%Si) have been investigated. Dry sliding wear tests were performed using a block on ring type tribometer under controlled environments. The experiments were performed in a load range between 0.2 N and 300 N at a constant speed of 1 m/s. The testing environments were a dry …
Mobility Enhancement Of Manganese Dioxide Produced During In-Situ Chemical Oxidation Of Tce By Potassium Permanganate Using Sodium Polyphosphate., Kanwartej Singh Sra
Mobility Enhancement Of Manganese Dioxide Produced During In-Situ Chemical Oxidation Of Tce By Potassium Permanganate Using Sodium Polyphosphate., Kanwartej Singh Sra
Electronic Theses and Dissertations
MnO2 is a product of in-situ oxidation of trichloroethylene (TCE) by KMnO4. This species tends to precipitate and hinder the oxidation process thereby reducing the treatment efficiency in more than one way. The main objective of this research was to enhance the mobility of MnO 2 precipitates using sequestration technique. A one dimensional column was designed to study the effect of sodium polyphosphate addition to the reaction solution containing KMnO4. The solution was injected to the silica sand artificially contaminated by WE and the mass removal rates were studied against the removal rates when no polyphosphate was added into the …
Adhesion And Material Transfer Between Aluminum And Surfaces Coated With Diamond-Like Carbon And Other Coatings., Erkan Konca
Adhesion And Material Transfer Between Aluminum And Surfaces Coated With Diamond-Like Carbon And Other Coatings., Erkan Konca
Electronic Theses and Dissertations
Adhesion and transfer of aluminum to the surfaces of tool coatings that are potential candidates for dry machining of Al-Si alloys were investigated. First, 319 Al alloy pins were tested against various industrial coatings (CrN, TiB2, TiAlN, TiN, and TiCN) using a pin-on-disc tribometer. The analyzed Scanning Electron Microscope (SEM) images of the wear tracks were used to rank the coatings according to the amount of Al transferred on their surfaces. In general, the TiB2 and TiCN coatings exhibited the least amount of Al transfer on their surfaces compared to the other coatings. Second, the tribological behaviour of the diamond-like …
Efficient Quadratic Placement For Fpgas., Yonghong Xu
Efficient Quadratic Placement For Fpgas., Yonghong Xu
Electronic Theses and Dissertations
Field Programmable Gate Arrays (FPGAs) are widely used in industry because they can implement any digital circuit on site simply by specifying programmable logic and their interconnections. However, this rapid prototyping advantage may be adversely affected because of the long compile time, which is dominated by placement and routing. This issue is of great importance, especially as the logic capacities of FPGAs continue to grow. This thesis focuses on the placement phase of FPGA Computer Aided Design (CAD) flow and presents a fast, high quality, wirelength-driven placement algorithm for FPGAs that is based on the quadratic placement approach. In this …
Improving Enterprise Business Processes With Systems Analysis And Design Methodologies And Tools., Anas Radwan Kazaal
Improving Enterprise Business Processes With Systems Analysis And Design Methodologies And Tools., Anas Radwan Kazaal
Electronic Theses and Dissertations
Enterprises have to be organized in a business process oriented way. This is in order to be successful in a changing and challenging business environment including uncertainty and complexity in managing business and manufacturing processes. The main objective of this thesis is to implement comprehensive modelling methodologies and tools that capture all useful information included within the enterprise business processes. This has been achieved first through implementing the Systems Analysis and Design (SAD) methodologies and tools for integrating the business design processes. The implementation should recognize the enterprise organization view, data and information view, function view, and also product/service view. …
Triz Theory And Automotive Safety Systems Development, Lu Wang
Triz Theory And Automotive Safety Systems Development, Lu Wang
Electronic Theses and Dissertations
Engineering design tasks involve a wide range of theories and methods. Most of the existing engineering practices aim at mapping given requirements and demands into a list of specifications describing a feasible product. Nevertheless, formal design theories are only available at later design phases, which are performed after a feasible design concept has been proposed and verified. The bottleneck of new product development projects usually lies in the generation of initial feasible concepts. Theory of Inventive Problem Solving (TRIZ), originated in Russia, was developed to address this issue of generating the initial concepts. In this thesis, we analyze the development …
An Independent Controller For Active Diesel Exhaust Aftertreatment., Yue Wu
An Independent Controller For Active Diesel Exhaust Aftertreatment., Yue Wu
Electronic Theses and Dissertations
An independent controller was proposed to perform real-time diagnosis and modeling based control for diesel aftertreatment devices, such as the diesel particulate filters (DPF) and the lean NOx traps (LNT). The diesel aftertreatment devices for this research were in active flow control configuration. As opposed to passive aftertreatment control where the engine tailors the raw exhaust conditions, in active aftertreatment configuration, the raw exhaust conditions were modified with independent controls, such as aftertreatment temperature control, exhaust flow control, and aftertreatment excess air/fuel ratio (A) control. The determination of the diesel engine transient exhaust gas temperature is essential for effective active …
An Innovative Engineering Design Model By The Aid Of Triz Methodology And Cae Technology., Ning (Nathan) Yu
An Innovative Engineering Design Model By The Aid Of Triz Methodology And Cae Technology., Ning (Nathan) Yu
Electronic Theses and Dissertations
This thesis presents research that advocates process, methods and new technology for performance related robustness improvements in product development. Rapid advances in technology in recent years have set new demands on product development. As a consequence, an increasing variety of products are built on heterogeneous technologies. Specialists from different engineering disciplines must cooperate to a greater extent than before in order to understand the products. Increased cooperation and heterogeneous technologies in products set high demands on rapid product development models in order to deliver products of high quality in short lead time, at low cost. One of the most important …
Dynamic Analysis Of Guyed Antenna Towers For Seismic Loads., Hussam M. Meshmesha
Dynamic Analysis Of Guyed Antenna Towers For Seismic Loads., Hussam M. Meshmesha
Electronic Theses and Dissertations
The increasing demand for personal communication services (PCS), such as digital cell phones and pagers, as well as digital television (DTV), has created new challenges for creating and maintaining telecommunications towers. For such communication tools, antenna towers are the best choice because they are relatively economical and effective for remote transmission, especially in North America where land area is large. Wireless firms are further pressured to complete digital systems within the next five years and to provide "seamless" coverage. The Canadian Standard for Antennas, Towers and Antenna-Supporting Structures, CSA-S37-01, provides guidance for seismic analysis of lattice towers. However, simplified design …
'Green' Manufacturing: A Life Cycle Inventory Of The Automotive Paint Process And Protocols For Industry Application., Angelos Anastassopoulos
'Green' Manufacturing: A Life Cycle Inventory Of The Automotive Paint Process And Protocols For Industry Application., Angelos Anastassopoulos
Electronic Theses and Dissertations
In response to growing interest in 'green' vehicles, Life Cycle Analysis (LCA) and Life Cycle Inventory (LCI) concepts can quantify the automobile's environmental impacts. Potential benefits include Design-for-Environment (DfE) opportunities, increased manufacturing efficiencies, and future application to consumer-based eco-rating systems. Detailed and up-to-date LCI data for general application by LCI practitioners does not exist at this time for the majority of Manufacturing/Assembly processes in North America, including the automotive paint process. With an Original Equipment Manufacturer (OEM) industry partner's commitment to a publicly available LCI database (i.e., NREL LCI Database), however, a representative vehicle assembly facility was selected for completion …
Investigation Into Arithmetic Sub-Cells For Digital Multiplication., G. Michael Howard
Investigation Into Arithmetic Sub-Cells For Digital Multiplication., G. Michael Howard
Electronic Theses and Dissertations
A study of several low-power and high-speed (3,2) counter designs is initially presented, then based on these findings, a new 4:2 compressor design is introduced and proven against other existing and newly devised 4:2 compressors using various logic styles. The results obtained with regards to speed, power and size were used to categorize the circuits in terms of individual and cumulative performance characteristics. A complete 16-bit multiplier design which uses a highly efficient layout scheme along with the top performing 4:2 compressor form the above study is presented. A second multiplier using industry standard (3,2) counters in a 4:2 compressor …
Investigation Of Total Gaseous Mercury In The Atmosphere Of The Great Lakes And St. Lawrence River Basin., Hongyu You
Investigation Of Total Gaseous Mercury In The Atmosphere Of The Great Lakes And St. Lawrence River Basin., Hongyu You
Electronic Theses and Dissertations
Mercury (Hg) is a highly toxic pollutant, and it can undergo long-range transport in the atmosphere. Hg is a pollutant of concern because of its tendency to accumulate and concentrate in biota. In this study, a statistical analysis of total gaseous mercury (TGM) was carried out using seven years of measurements at three Canadian Atmospheric Mercury Measurement Network (CAMNet) sites in the Great Lakes basin and three years measurements at two CAMNet sites in the St. Lawrence River basin. The average TGM concentrations ranged from 1.59 +/- 0.24 to 1.84 +/- 0.39 ng m-3 at the five sites. Two of …
Microbial Production Of Hydrogen Under Mesophilic Conditions., Nabin Chowdhury
Microbial Production Of Hydrogen Under Mesophilic Conditions., Nabin Chowdhury
Electronic Theses and Dissertations
Fermentative hydrogen production from biomass using mixed anaerobic cultures has a greater potential to be developed as a practical biohydrogen system than systems utilizing pure cultures. To optimize hydrogen production, it is important to inhibit hydrogen consumers during glucose fermentation. Long chain fatty acids (LCFAs) are inhibitors of aceticlastic methanogenic bacteria and these fatty acids could act as hydrogenotroph methanogenic inhibitor in fermentative hydrogen production. Batch studies were conducted to assess the effects of two C18 LCFAs on microbial hydrogen production from glucose under mesophilic conditions. Experiments were conducted using different concentrations of linoleic acid (LA) and oleic acid (OA) …
Mobile-Ip Ad-Hoc Network Mpls-Based With Qos Support., Sasan Adibi
Mobile-Ip Ad-Hoc Network Mpls-Based With Qos Support., Sasan Adibi
Electronic Theses and Dissertations
The support for Quality of Service (QoS) is the main focus of this thesis. Major issues and challenges for Mobile-IP Ad-Hoc Networks (MANETs) to support QoS in a multi-layer manner are considered discussed and investigated through simulation setups. Different parameters contributing to the subjective measures of QoS have been considered and consequently, appropriate testbeds were formed to measure these parameters and compare them to other schemes to check for superiority. These parameters are: Maximum Round-Trip Delay (MRTD), Minimum Bandwidth Guaranteed (MBG), Bit Error Rate (BER), Packet Loss Ratio (PER), End-To-End Delay (ETED), and Packet Drop Ratio (PDR) to name a …
Novel Arithmetic Implementations Using Cellular Neural Network Arrays., Youssef Ibrahim
Novel Arithmetic Implementations Using Cellular Neural Network Arrays., Youssef Ibrahim
Electronic Theses and Dissertations
The primary goal of this research is to explore the use of arrays of analog self-synchronized cells---the cellular neural network (CNN) paradigm---in the implementation of novel digital arithmetic architectures. In exploring this paradigm we also discover that the implementation of these CNN arrays produces very low system noise; that is, noise generated by the rapid switching of current through power supply die connections---so called di/dt noise. With the migration to sub 100 nanometer process technology, signal integrity is becoming a critical issue when integrating analog and digital components onto the same chip, and so the CNN architectural paradigm offers a …
On The Distortion Of Turbulent Flow Through A Contraction Imposed By Cylinders., Babak Emami
On The Distortion Of Turbulent Flow Through A Contraction Imposed By Cylinders., Babak Emami
Electronic Theses and Dissertations
The effects of a cylindrical contraction, consisting of two half cylinders installed next to the side walls of a wind tunnel and a full cylinder in between, on the distortion of a turbulent flow were experimentally investigated. The cylinders were 15.2 cm (6 in) in diameter and 76.2 cm (30 in) in height installed in a closed loop wind tunnel with a 76.2 cm by 76.2 cm (30 in by 30 in) cross section. Turbulent flow was generated by means of a perforated plate situated at the entrance of the wind tunnel. The nominal flow velocity was fixed at 5 …
Parametric Analysis Of Bolted Flange Connections Of Circular Monopoles., Olumadunwa Olusanya
Parametric Analysis Of Bolted Flange Connections Of Circular Monopoles., Olumadunwa Olusanya
Electronic Theses and Dissertations
The present study involved the parametric analysis of bolted flange connections of eighteen different circular monopoles. The parameters considered were the number of bolts (8, 6, and 4) and thickness of flange plate [25.4 mm (1.0 in.), 19.05 mm (0.75 in.) and 12.7 mm (0.50 in.)]. These were analyzed under stiffened and unstiffened conditions. Four, two and four stiffeners, 12.7 mm (0.50 in.) thick, were used with 8-, 6- and 4-bolt arrangements. Each finite element model is made up of a small diameter (171.5 mm) circular pipe and a large diameter (327 mm) circular pipe both welded to circular flanges. …
Estimation Of Volumetric Flow Rate Through A Circular Duct: Equal Area Versus Log-Tchebycheff Method., Md Ramiz Ahemad
Estimation Of Volumetric Flow Rate Through A Circular Duct: Equal Area Versus Log-Tchebycheff Method., Md Ramiz Ahemad
Electronic Theses and Dissertations
Proper control of airflow through a duct is critical in HVAC application. At present, the airflow rate is typically estimated by means of Equal Area and Log-Tchebycheff methods. Both methods deduce the flow rate based on velocities measured at discrete locations in a cross section; the difference is associated with the rules that prescribe the specific locations. This research aims at making a step towards resolving the existing debate as to which method is preferable for a given situation. To achieve this, two-dimensional numerical simulations of air at a uniform velocity entering a straight circular duct of 60D length were …
Vehicle Interior Sound And Vibration Numerical Estimation Method Based On Engine Radiated Sound And Mount Vibration, Nikolina Kojovic
Vehicle Interior Sound And Vibration Numerical Estimation Method Based On Engine Radiated Sound And Mount Vibration, Nikolina Kojovic
Electronic Theses and Dissertations
A study was undertaken to develop a numerical estimation method for vehicle interior sound and vibration based on 5.4L V8 engine radiated sound and mount vibration and to quantify the contributions of vibroacoustic paths to vehicle interior sound and vibration. The modal analysis included acoustic and mechanical excitation of the frame and body assembly of a light truck. It was performed to estimate the sound and vibration transmission characteristics from the engine compartment to vehicle interior. The respective frequency response functions were then combined with frequency based source (engine radiated sound and forces transmitted through the mounts) data to estimate …
Two-Dimensional Scour Hole Problem: Role Of Fluid Structures, Alex Bey
Two-Dimensional Scour Hole Problem: Role Of Fluid Structures, Alex Bey
Electronic Theses and Dissertations
An experimental program was carried out to further understand the scour caused by a plane wall jet. To this end, a two-dimensional laser Doppler anemometer was used to characterize the velocity field at various stations in the scour hole region. Present observations indicate that different types of flow structures influence scour at different time periods. Following vigorous digging caused principally by jet shear forces and impingement at the start of the test, the flow was characterized by the presence of longitudinal axial vortices, turbulent bursts and movement of the jet impingement point during the later stages. Attempts have been made …
A High Level Synthesis Of A Fibre Channel Core For A System-On-Chip Implementation., Till. Kuendiger
A High Level Synthesis Of A Fibre Channel Core For A System-On-Chip Implementation., Till. Kuendiger
Electronic Theses and Dissertations
A high performance standardized System-on-Chip (SoC ) communication system has been developed as an embedded core. A high level synthesis of a Fibre Channel core has been realized that takes advantage of the performance advantages and specifications associated with the Fibre Channel protocol. A soft IP core of a Fibre Channel port is presented in the form of a register transfer level (RTL) descriptor language which can be implemented in arbitrary target technologies. A full-speed (1.0625 GHz link clock) sign-off quality tape-out of the design in TSMC's 0.18 mum technology has been carried out using a design flow centered on …