Electrical and Computer Engineering Commons^™

Nanostructured Morphologies In Glassy Polymer Networks, Brian Greenhoe

Dissertations

The body of this work describes a novel approach for the dispersion of multi-walled carbon nanotubes in a high T_g epoxy prepolymer matrix using a twin screw high-shear continuous reactor. The method demonstrated improves on previous dispersion methods in several ways. It offers increased efficiency through excellent heat transfer, while being solvent-less, scale-able, and tailorable to drive dispersion states to judiciously chosen dispersion states. Furthermore, it was shown that dispersion state and agglomerate morphology can be directed, in several ways, through processing conditions and also by controlling the matrix viscosity profile through cure. Broadband dielectric spectroscopy, optical hot-stage microscopy, …

Development Of Printed Cross-Functional Sensors For Gearbox Lubricant Prognostics, John Omondi Manyala

Dissertations

Lubricant oil degradation is a major cause of failures in transportation machinery such as pumps, engines, and gearboxes. Proactive oil maintenance techniques such as the off-line oil sampling for laboratory analysis are not only costly but are also susceptible to various influences during the oil sampling, transportation and testing. In this study, an on-line oil condition monitoring system is presented with an integrated predictive prognostic scheme, describing the evolution in time of the identified fault indicators for purposes of estimating the remaining useful life of oil in real-time inside the gearbox. The proposed methodology facilitates on-demand gearbox maintenance rather than …

Indoor Localization Of Mobile Devices Based On Wi-Fi Signals Via Convex Optimization And Bregman Divergence, Osamah Ali Abdullah

Dissertations

Indoor positioning systems (IPS) have been the subject of intense academic and industrial research due to the significance of such systems in a wide range of applications. Applications of IPS include indoor navigation and its associated user services, especially by users in large complex buildings, by emergency healthcare services to locate a patient, and people with vision impairments. IPS can also play an important role in other applications that require tracking and observation, such as those used in care for the elderly or security purposes. Therefore, much research has been focused on IPS methods that fingerprint the Received Signal Strength …

Electrical Characterization Of High-K Gate Dielectrics For Advanced Cmos Gate Stacks, Yi Ming Ding

Dissertations

The oxide/substrate interface quality and the dielectric quality of metal oxide semiconductor (MOS) gate stack structures are critical to future CMOS technology. As SiO₂ was replaced by the high-k dielectric to further equivalent oxide thickness (EOT), high mobility substrates like Ge have attracted increasing in replacing Si substrate to further enhance devices performance. Precise control of the interface between high-k and the semiconductor substrate is the key of the high performance of future transistor. In this study, traditional electrical characterization methods are used on these novel MOS devices, prepared by advanced atomic layer deposition (ALD) process and with pre …

The Influence Of The Electric Supply Industry On Economic Growth In Less Developed Countries, Edward Richard Bee

Dissertations

This study measures the impact that electrical outages have on manufacturing production in 135 less developed countries using stochastic frontier analysis and data from World Bank’s Investment Climate surveys. Outages of electricity, for firms with and without backup power sources, are the most frequently cited constraint on manufacturing growth in these surveys.

Outages are shown to reduce output below the production frontier by almost five percent in Africa and by a lower percentage in South Asia, Southeast Asia and the Middle East and North Africa. Production response to outages is quadratic in form. Outages also increase labor cost, reduce exports …

Sensing Gyroscopic Properties Of Rotating Magnetic Nanoparticles In Solution, Brian Gerald Krug

Dissertations

A new sensor using magnetic nanoparticles and rotating magnetic fields has been developed. By spinning the nanoparticles in a rotating magnetic field, it is feasible to infer angular position and inertia if an external force is applied to the system. The nanoparticles are treated as a multitude of miniature gyroscopes whose overall effect can be combined as one single gyroscope. Two sensors were built to test the feasibility, both containing Fe3O4 nanoparticles.

The typical input current was 250 milliamps. When the sensor deviated from its magnetic axis by a small angle, the input current changed between 1 and 2 milliamps …

Development And Evaluation Of Matrix Material Formulations For Potential Integration Into Immunodiagnostic Biosensors, Payam Aminayi

Dissertations

This study supports the development, characterization and optimization of biosensor material formulations for immunodiagnostic applications based on experimental findings and hypotheses by Wang and Wu [1, 2], and using a test-plate apparatus and thin-film design developed by Young [3].

Certain biosensors working on the basis of conductance/impedance changes have demonstrated their potential to detect various bacteria, enzymes, and biomolecules due to their enhanced electrical properties with incorporated single-walled carbon nanotubes (SWNT). From the work conducted in our laboratory, we are attempting to determine and develop a matrix formulation containing highly dispersed SWNT, antibody and other components that elicit a significantly …

Vector Processor Virtualization: Distributed Memory Hierarchy And Simultaneous Multithreading, Seyedamin Rooholamin

Dissertations

Taking advantage of DLP (Data-Level Parallelism) is indispensable in most data streaming and multimedia applications. Several architectures have been proposed to improve both the performance and energy consumption for such applications. Superscalar and VLIW (Very Long Instruction Word) processors, along with SIMD (Single-Instruction Multiple-Data) and vector processor (VP) accelerators, are among the available options for designers to accomplish their desired requirements. On the other hand, these choices turn out to be large resource and energy consumers, while also not being always used efficiently due to data dependencies among instructions and limited portion of vectorizable code in single applications that deploy …

Cloud-Aided Wireless Systems: Communications And Radar Applications, Shahrouz Khalili

Dissertations

This dissertation focuses on cloud-assisted radio technologies for communication, including mobile cloud computing and Cloud Radio Access Network (C-RAN), and for radar systems.

This dissertation first concentrates on cloud-aided communications. Mobile cloud computing, which allows mobile users to run computationally heavy applications on battery limited devices, such as cell phones, is considered initially. Mobile cloud computing enables the offloading of computation-intensive applications from a mobile device to a cloud processor via a wireless interface. The interplay between offloading decisions at the application layer and physical-layer parameters, which determine the energy and latency associated with the mobile-cloud communication, motivates the inter-layer …

Instruction Fusion And Vector Processor Virtualization For Higher Throughput Simultaneous Multithreaded Processors, Yaojie Lu

Dissertations

The utilization wall, caused by the breakdown of threshold voltage scaling, hinders performance gains for new generation microprocessors. To alleviate its impact, an instruction fusion technique is first proposed for multiscalar and many-core processors. With instruction fusion, similar copies of an instruction to be run on multiple pipelines or cores are merged into a single copy for simultaneous execution. Instruction fusion applied to vector code enables the processor to idle early pipeline stages and instruction caches at various times during program implementation with minimum performance degradation, while reducing the program size and the required instruction memory bandwidth. Instruction fusion is …

On Greening Optical Access Networks, Mina Taheri Hosseinabadi

Dissertations

With the remarkable growth of fiber-based services, the number of FTTx subscribers has been dramatically increasing in recent years. Owing to the environmental concern, reducing energy consumption of optical access networks has become an important issue for network designers. In Ethernet passive optical network (EPON), the optical line terminal (OLT) located at the central office broadcasts the downstream traffic to all optical network units (ONUs), each of which checks all arrival downstream packets to obtain those destined to itself. Since traffic of ONUs changes dynamically, properly defining the sleep mode for idle ONUs can potentially save a significant amount of …

Compressive Sensing Framework For Mass Spectrometry Data Analysis, Khalfalla Ahmad Kh. Awedat

Dissertations

Mass Spectrometry (MS) data is ideal for identifying unique bio-signatures of diseases. However, the high dimensionality of MS data hinders any promising MS-based proteomics development. The goal of this dissertation is to develop an accurate classification tool by employing compressive sensing (CS). Not only can CS significantly reduce MS data dimensionality, but it also will allow for full reconstruction of original data. The framework developed in this work is based on using L2 and a mixed L2-L1 norms, allowing an overdetermined system to be resolved. The results show that the L2- based algorithm with regularization terms has a better performance …

Verification Of Emotion Recognition From Facial Expression, Yanjia Sun

Dissertations

Analysis of facial expressions is an active topic of research with many potential applications, since the human face plays a significant role in conveying a person’s mental state. Due to the practical values it brings, scientists and researchers from different fields such as psychology, finance, marketing, and engineering have developed significant interest in this area. Hence, there are more of a need than ever for the intelligent tool to be employed in the emotional Human-Computer Interface (HCI) by analyzing facial expressions as a better alternative to the traditional devices such as the keyboard and mouse.

The face is a window …

Generalized Dft: Extensions In Communications, Yuewen Wang

Dissertations

Discrete Fourier Transform (DFT) is a restricted version of Generalized DFT (GDFT) which offers a very limited number of sets to be used in a multicarrier communication system. In contrast, as an extension on Discrete Fourier Transform (DFT) from the linear phase to non-linear phase, the proposed GDFT provides many possible carrier sets of various lengths with comparable or better performance than DFT. The availability of the rich library of orthogonal constant amplitude transforms with good performance allows people to design adaptive systems where user code allocations are made dynamically to exploit the current channel conditions in order to deliver …

Novel Stretchable Printed Wearable Sensor For Monitoring Body Movement, Temperature And Electrocardiogram, Along With The Readout Circuit, Ali Eshkeiti

Dissertations

Conformal and stretchable wearable sensors provide vital real time information about individual’s health conditions. In this work, Traditional printing methods are used for fabrication of stretchable and wearable sensors which can be mounted on the human skin for the purpose of health tracking. In addition, screen printing technology was utilized to develop printed and flexible electronic circuit board which can be used as a readout circuit along with fabricated wearable sensors. The dissertation is organized and pursued in three projects.

In the first project, screen printing was used to fabricate multi-layer PCBs using printed deposited materials on three distinct substrates. …

Implementation Of Traditional Printing Techniques For The Development Of Flexible Printed Sensors, Sai Guruva Reddy Avuthu

Dissertations

Printed electronics has gained a remarkable interest over the past decade for the fabrication of cost efficient electronic devices, with a major focus on the development of flexible sensors. This dissertation focuses on the fabrication of flexible sensors using traditional printing processes such as screen, inkjet and gravure printing.

A flexible organic thin film transistor (OTFT) was successfully fabricated on a polyethylene terephthalate (PET) substrate and employed as a humidity sensor. Aluminum gate electrode was thermally evaporated on PET and UV clear dielectric layer was spin coated. Source and drain silver interdigitated electrodes were screen printed. 6,13-bis(triisopropylsilylethynyl) pentacene, a humidity …

Exploration Of Stimulus Current Energy Reduction And Bifurcation Dynamics In Conductance-Based Neuron Models Using Optimal Control Theory, Michael E. Ellinger

Dissertations

Hodgkin-Huxley type conductance-based models can simulate the effect of time-varying injected stimulus currents on the neuron membrane voltage. The dynamics simulated by these model types enables investigation of the biophysical basis of neuronal activity which is fundamental to higher level function. Broadened understanding the basis of nervous system function could lead to development of effective treatment for related diseases, disorders, and the effects of trauma. In this dissertation, optimal control is used with conductance-based neuron models to develop a "Reduced Energy Input Stimulus Discovery Method." Within the method, an objective function balances two competing criteria: tracking a reference membrane voltage …

Optimization Methods For Active And Passive Localization, Nil Garcia

Dissertations

Active and passive localization employing widely distributed sensors is a problem of interest in various fields. In active localization, such as in MIMO radar, transmitters emit signals that are reflected by the targets and collected by the receive sensors, whereas, in passive localization the sensors collect the signals emitted by the sources themselves. This dissertation studies optimization methods for high precision active and passive localization.

In the case of active localization, multiple transmit elements illuminate the targets from different directions. The signals emitted by the transmitters may differ in power and bandwidth. Such resources are often limited and distributed uniformly …

Blind Source Separation For Feature Detection And Segmentation In Ground Penetrating Radar (Gpr) Lmaging Of Concrete Bridge Decks For Nondestructive Condition Assessment, Vincent Krause

Dissertations

Concrete bridge decks require periodic condition assessment and preventive maintenance to extend their useful lifespan. Nondestructive evaluation methods such as Ground Penetrating Radar (GPR) are slowly beginning to replace or complement the manual (visual) assessment of bridge conditions for detecting defects at their early stages. However, GPR scans of bridge decks are frequently cluttered with high amplitude reflections from known parts of the bridge deck, which make the detection of defects’ low amplitude reflections difficult. One such known part is the embedded steel reinforcement bars known as rebar.

This dissertation presents a novel approach to the automated detection of defects …

Reliability Study Of Zr And Al Incorporated Hf Based High-K Dielectric Deposited By Advanced Processing, Md Nasir Uddin Bhuyian

Dissertations

Hafnium-based high-x dielectric materials have been successfully used in the industry as a key replacement for SiO₂ based gate dielectrics in order to continue CMOS device scaling to the 22-nm technology node. Further scaling according to the device roadmap requires the development of oxides with higher x values in order to scale the equivalent oxide thickness (EOT) to 0.7 nm or below while achieving low defect densities. In addition, next generation devices need to meet challenges like improved channel mobility, reduced gate leakage current, good control on threshold voltage, lower interface state density, and good reliability. In order to …

Optical Properties Of Strain-Engineered Multilayer Si/Sige Nanostructures, Selina Akter Mala

Dissertations

The long carrier radiative lifetimes in indirect band gap semiconductors such as crystalline Si (c-Si) and Ge impede the development of efficient light-emitting devices and lasers. Multilayer Si/SiGe nanostructures are considered to be the strong candidates for efficient and high-speed optoelectronic devices integrated into CMOS platforms. Since c-Si and Ge have a considerable lattice mismatch of ~ 4.2%, Si/Si_1-xGe_x(x < 0.5) nanostructures in the form of nano-layers (NLs) or cluster multilayers (CMs) modify the band structure and create non-uniform strain distribution. Engineering of Si/Si_1-xGe_xnanostructures with the predicted composition and interface abruptness, which controls spatial separation between electrons and holes and carrier radiative recombination rate, is critical in producing the desired fast and efficient photoluminescence …

Synchrophasor Assisted Efficient Fault Location Techniques In An Active Distribution Network, Anil Khanal

Dissertations

Reliability of an electrical system can be improved by an efficient fault location identification for the fast repair and remedial actions. This scenario changes when there are large penetrations of distributed generation (DG) which makes the distribution system an active distribution system. An efficient use of synchrophasors in the distribution network is studied with bidirectional power flow, harmonics and low angle difference consideration which are not prevalent in a transmission network. A synchrophasor estimation algorithm for the P class PMU is developed and applied to identify efficient fault location. A fault location technique using two ended synchronized measurement is derived …

A Novel Approach For Identifying Cloud Clusters Developing Into Tropical Cyclones, Chaunte' W. Lacewell

Dissertations

Providing advance notice of rare events, such as a cloud cluster (CC) developing into a tropical cyclone (TC), is of great importance. Having advance warning of such rare events possibly can help avoid or reduce the risk of damages and allow emergency responders and the affected community enough time to respond appropriately. Considering this, forecasters need better data mining and data driven techniques to identify developing CCs. Prior studies have attempted to predict the formation of TCs using numerical weather prediction models as well as satellite and radar data. However, refined observational data and forecasting techniques are not always available …

Process Control & Automation Of A Batch Reactor, James Kelly

Dissertations

The development of a split range PID controller with SCADA screens to facilitate manual and automatic control of a pilot plant scale batch reactor is presented in this thesis. Since the characteristics of the system were unknown a step response was obtained from the system and from the experimental results a model of the system was developed and analysed. The PID controller for the system was implemented via an Allen Bradley MicroLogix 1100 Programmable Logic Controller with the human interface for the controller being a SCADA system that was developed using the software package LabVIEW a visual programming language. From …

Global Optimization Methods For Localization In Compressive Sensing, Marco Rossi

Dissertations

The dissertation discusses compressive sensing and its applications to localization in multiple-input multiple-output (MIMO) radars. Compressive sensing is a paradigm at the intersection between signal processing and optimization. It advocates the sensing of “sparse” signals (i.e., represented using just a few terms from a basis expansion) by using a sampling rate much lower than that required by the Nyquist-Shannon sampling theorem (i.e., twice the highest frequency present in the signal of interest). Low-rate sampling reduces implementation’s constraints and translates into cost savings due to fewer measurements required. This is particularly true in localization applications when the number of measurements is …

Congestion Control, Energy Efficiency And Virtual Machine Placement For Data Centers, Yan Zhang

Dissertations

Data centers, facilities with communications network equipment and servers for data processing and/or storage, are prevalent and essential to provide a myriad of services and applications for various private, non-profit, and government systems, and they also form the foundation of cloud computing, which is transforming the technological landscape of the Internet. With rapid deployment of modern high-speed low-latency large-scale data centers, many issues have emerged in data centers, such as data center architecture design, congestion control, energy efficiency, virtual machine placement, and load balancing.

The objective of this thesis is multi-fold. First, an enhanced Quantized Congestion Notification (QCN) congestion notification …

Modeling, Control And Simulation Of Control-Affine Nonlinear Systems With State-Dependent Transfer Functions, Roger Kobla Kwadzogah

Dissertations

There has been no known research that applies nonlinear transfer function to a nonlinear control problem. The belief is that nonlinear systems have no transfer functions. The Laplace transformation required to define transfer functions is not tractable mathematically when the coefficients of the differential equation are functions of state, output and control variables. In other words, it is not defined for systems that do not obey principles of superposition. Only linear systems obey this principle. Therefore, this dissertation work represents the very first research to demonstrate how transfer functions can be used to represent and design feedback control for nonlinear …

Resource Allocation For Wireless Relay Networks, Hanan Hassan Al-Tous

Dissertations

In this thesis, we propose several resource allocation strategies for relay networks in the context of joint power and bandwidth allocation and relay selection, and joint power allocation and subchannel assignment for orthogonal frequency division multiplexing (OFDM) and orthogonal frequency division multiple access (OFDMA) systems. Sharing the two best ordered relays with equal power between the two users over Rayleigh flat fading channels is proposed to establish full diversity order for both users. Closed form expressions for the outage probability, and bit error probability (BEP) performance measures for both amplify and forward (AF) and decode and forward (DF) cooperative communication …

An Adaptive Kalman Filter For Voltage Sag Detection In Power Systems, Hisham Odeh Alrawashdeh

Dissertations

The exact values of the noise covariance matrix of the Kalman filter state vector Q and the measured signal noise covariance matrix R must be obtained in order to achieve the optimal performance of the Kalman filter. There have been many techniques and assumptions made to evaluate and compute Q and R. The effects of Q and R are investigated in detail in this dissertation. Based on these investigations, the Kalman filter has been modeled to detect the fundamental signal amplitude variations of power system signals. This technique helps in evaluating voltage sags in power systems.

Two algorithms are …

Design And Implementation Of An X-Band Passive Rfid Tag, Praharshin Melaka Senadeera

Dissertations

This research presents a novel fully integrated energy harvester, matching network, multi-stage RF-DC rectifier, mode selector, RC oscillator, LC oscillator, and X-band power amplifier implemented in IBM 0.18-µm RF CMOS technology. We investigated different matching schemes, antennas, and rectifiers with focus on the interaction between building blocks. Currently the power amplifier gives the maximum output power of 5.23 dBm at 9.1GHz. The entire RFID tag circuit was designed to operate in low power consumption. Voltage sensor circuit which generates the enable signal was designed to operate in very low current. All the test blocks of the RFID tag were tested. …