Electrical and Computer Engineering Commons^™

Enhancing Wireless Security Using Relay Based Cooperative Networks., Mohammad A. Kishk

Electronic Theses and Dissertations

No abstract provided.

Coherent Phonons In Bismuth Film Observed By Ultrafast Electron Diffraction, A. Bugayev, A. Esmail, M. Abdel-Fattah, H. E. Elsayed-Ali

Applied Research Center Publications

The generation of coherent phonons in polycrystalline bismuth film excited with femtosecond laser pulse is observed by ultrafast time-resolved electron diffraction. The dynamics of the diffracted intensities from the (110), (202), and (024) lattice planes show pronounced oscillations at 130-150 GHz. The origin of these coherent acoustic phonons is discussed in view of optical phonon decay into two acoustic phonons. Different drop times in the intensity of the diffraction orders are observed and interpreted as anisotropy in the energy transfer rate of coherent optical phonons.

Direct Digital Frequency Synthesizer Architecture For Wireless Communication In 90 Nm Cmos Technology, Tri Trong Nguyen

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Software radio is one promising field that can meet the demands for low cost, low power, and high speed electronic devices for wireless communication. At the heart of software radio is a programmable oscillator called a Direct Digital Synthesizer (DDS). DDS has the capabilities of rapid frequency hopping by digital software control while operating at very high frequencies and having sub-hertz resolution. Nevertheless, the digital-to-analog converter (DAC) and the read-only-memory (ROM) look-up table, building blocks of the DDS, prevent the DDS to be used in wireless communication because they introduce errors and noises to the DDS and their performances deteriorate …

Design Of A Low Power And Area Efficient Digital Down Converter And Sinc Filter In Cmos 90-Nm Technology, Steven John Billman

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A digital down converter (DDC) typically receives a digital input that has been generated by an analog to digital converter (ADC) operating at intermediate frequency (IF) in an RF receiver chain. The function of the DDC is to down convert the IF signal to baseband in phase (I) and quadrature (Q) signals and is a very important component in wireless receivers. A Digital Down Converter (DDC) is developed based on square wave local oscillators facilitating a multiplier-less implementation with no constraints on the sampling frequency. The DDC includes a pseudo multi-rate SINC low pass filter which exhibits better performance compared …

Structured Silicon Macropore As Anode In Lithium Ion Batteries, Xida Sun

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Porous silicon (PS) membranes for lithium-ion batteries (LIBs) anode applications were developed, demonstrated and characterized systematically in this work. Electrochemical measurements were conducted on both Si-wafer supported and free-standing porous Si membranes. It turned out that the specific capacity of LIBs was enhanced remarkably by PS based anode. PS was fabricated by using electrochemical anodization in a mixed solution of Dimethylformamide (DMF) and Hydrofluoric acid (HF wt.49%). By varying the anodization conditions, including HF concentration, anodization etching time and current density, pores were formed in a p-type (1-20Ω cm) boron-doped silicon substrate. Scanning electron microscopy (SEM) was employed to investigate …

Computational Study Of The Seebeck Coefficient Of One-Dimensional Composite Nanostructures, Raseong Kim, Mark S. Lundstrom

Department of Electrical and Computer Engineering Faculty Publications

The Seebeck coefficient (S) of composite nano-structures is theoretically explored within a self-consistent electro-thermal transport simulation framework using the non-equilibrium Green’s function method and a heat diffusion equation. Seebeck coefficients are determined using numerical techniques that mimic experimental measurements. Simulation results show that, without energy relaxing scattering, the overall S of a composite structure is determined by the highest barrier within the device. For a diffusive, composite structure with energy relaxation due to electron-phonon scattering, however, the measured Sis an average of the position-dependent values with the weighting factor being the lattice temperature gradient. The results stress …

Full Dispersion Vs. Debye Model Evaluation Of Lattice Thermal Conductivity With A Landauer Approach, Changwook Jeong, Supriyo Datta, Mark S. Lundstrom

Department of Electrical and Computer Engineering Faculty Publications

Using a full dispersion description of phonons, the thermal conductivities of bulk Si and Bi2Te3 are evaluated using a Landauer approach and related to the conventional approach based on the Boltzmann transport equation. A procedure to extract a well-defined average phonon mean-free-path from the measured thermal conductivity and given phonon-dispersion is presented. The extracted mean-free-path has strong physical significance and differs greatly from simple estimates. The use of simplified dispersion models for phonons is discussed, and it is shown that two different Debye temperatures must be used to treat the specific heat and thermal conductivity (analogous to the two different …

Using Smartphones For Indoor Navigation, Benjamin Thomas Loulier

Purdue Polytechnic Masters Theses

This directed projet is about the use of smartphones for indoor navigation.

Nowadays, indoor navigation is a real challenge, we are all familiar with the multiple applications of GPS based navigation but all these applications cannot be transfered in an indoor environment as we cannot receive a GPS signal inside.

The document is composed of three different parts related to indoor navigation using smartphones. The first part presents an inertial positioning system for pedestrians walking in an indoor environment, this system is implemented on an iPhone 4. In the second part we introduce a positioning system using RFID tags scattered …

Electric Field Analysis Of Human Breast Tumors For Treatment By Electroporation, Poornima Agoramurthy

Purdue Polytechnic Masters Theses

Breast cancer is a frequently diagnosed disease in women, second only to cancers of the skin. According to the American Cancer Society there were approximately 210,000 new cases of breast cancer estimated in 2010 in the US, 20 % of which resulted in death. With such a high rate of incidence, there is clearly a need for alternate treatments, especially for in-operable tumors and chemo- and radio-resistive patients. Electrochemotherapy, a method by which high intensity, short duration electrical pulses are used to temporarily open pores of cells to enhance uptake of drugs, is gaining popularity in drug delivery for cancer …

Monitoring, Diagnosis, And Control For Advanced Anesthesia Management, Zhibin Tan

Wayne State University Dissertations

Modern anesthesia management is a comprehensive and the most critical issue in medical care. During the past dacades, a large amount of research works have been focused on the problems of monitoring anesthesia depth, modeling the dynamics of anesthesia patient for the purpose of control, prediction, and diagnosis.

Monitoring the anesthesia depth is not only for keeping the patient in adquate anesthesia level but also for preventing the patient from overdosing. Several EEG based indexes have been developed such as the BIS, and Entropy etc. for measuring depth. However, reports mentioned that those indexes in some cases fail in detecting …

Efficient Channel Allocation And Medium Access Organization Algorithms For Vehicular Networking, Zaydoun Yahya Rawashdeh

Wayne State University Dissertations

Due to the limited bandwidth available for Vehicular Ad-hoc Networks (VANETs), organizing the wireless channel access to efficiently use the bandwidth is one of the main challenges in VANET. In this dissertation, we focus on channel allocation and media access organization for Vehicle-to-Roadside Units (V2R) and Vehicle-to-Vehicle (V2V) communications. An efficient channel allocation algorithm for Roadside Unit (RSU) access is proposed. The goal of the algorithm is to increase system throughput by admitting more tasks (vehicles) and at the same time reduce the risk of the admitted tasks. The algorithm admits the new requests only when their requirements can be …

An Augmented Reality Interface For Multi-Robot Tele-Operation And Control, Sam Yung-Sen Lee

Wayne State University Dissertations

This thesis presents a seamlessly controlled human multi-robot system comprised of ground and aerial robots of semi-autonomous nature for source localization tasks. The system combines augmented reality interfaces capabilities with human supervisor's ability to control multiple robots. It used advanced path planning algorithms to ensure obstacles are avoided and that the operators are free for higher-level tasks. A sensor data fused AR view is displayed which helped the users pin point source information or help the operator with the goals of the mission. The paper studies a preliminary Human Factors evaluation of this system in which several interface conditions are …

Design And Fabrication Of A Prototype Aluminum Nitride-Based Pressure Sensor With Finite Element Analysis And Validation, Xinyu Du

Wayne State University Dissertations

Since 1985 when the first robot PUMA 560 was employed to place a needle during a brain CT biopsy, surgical robots have become ubiquitous in clinical surgeries. Despite its advantages and success in surgeries, the interactions between the robot and the surgeons remain deficient, especially for the pressure sensing which plays an important role. Inspired by our previous work on bacterial sensing, in the current work I have designed, fabricated, analyzed, and evaluated an innovative prototype pressure sensor based on Aluminum Nitride (AlN) Surface Acoustic Wave (SAW) and Shear Horizontal (SH)-SAW. This AlN-based device has unique superiority over other SAW …

Identification, State Estimation, And Adaptive Control Of Type I Diabetic Patients, Ali Mohamad Hariri

Wayne State University Dissertations

ABSTRACT

IDENTIFICATION, STATE ESTIMATION, AND ADAPTIVE CONTROL OF TYPE I DIABETIC PATIENTS

by

ALI MOHAMAD HARIRI

May 2012

Advisor: Dr. Le Yi Wang

Major: Electrical Engineering

Degree: Doctor of Philosophy

During the past few decades, biomedical modeling techniques have been applied to improve performance of a wide variety of medical systems that require monitoring and control. Diabetes is one of the most important medical problems. Most of the existing techniques assume the system to be time-invariant, and the original minimal model was modified by deleting some important parameters. In this research, the original minimal model that consists of three differential …

Processing Random Signals In Neuroscience, Electrical Engineering And Operations Research, Kalyan Raman

Wayne State University Dissertations

The topic of this dissertation is the study of noise in electrical engineering, neuroscience, biomedical engineering, and operations research through mathematical models that describe, explain, predict and control dynamic phenomena. Noise is modeled through Brownian Motion and the research problems are mathematically addressed by different versions of a generalized Langevin equation. Our mathematical models utilize stochastic differential equations (SDEs) and stochastic optimal control, both of which were born in the soil of electrical engineering. Central to this dissertation is a brain-physics based model of cerebrospinal fluid (CSF) dynamics, whose structure is fundamentally determined by an electrical circuit analogy. Our general …

Power Cable Fault Finding Using Pseudo Random Binary Sequences, Holger Geisler

Theses

The work that is presented in this thesis documents the results obtained from the pseudo random binary sequence (PRBS) cable testing method which utilises a pseudo noise (pN) sequence as a test stimulus to localise faults on a transmission line. The work targets the proof of concept of the PRBS method in a Coaxial cable as well as its eventual evaluation for fault testing accuracy and performance on a real-world underground steel wired armour (SWA) cable. Further, a novel hardware implementation of the method utilising a Field Programmable Gate Array (FPGA) is presented. The theory of the PRBS test method …

Global Change Reactive Background Subtraction, Edwin Premkumar Sathiyamoorthy

University of Kentucky Master's Theses

Background subtraction is the technique of segmenting moving foreground objects from stationary or dynamic background scenes. Background subtraction is a critical step in many computer vision applications including video surveillance, tracking, gesture recognition etc. This thesis addresses the challenges associated with the background subtraction systems due to the sudden illumination changes happening in an indoor environment. Most of the existing techniques adapt to gradual illumination changes, but fail to cope with the sudden illumination changes. Here, we introduce a Global change reactive background subtraction to model these changes as a regression function of spatial image coordinates. The regression model is …

Circuit Techniques On Improving Timing And Noise In Dynamic Cmos, Arvind Vaidyanadeswaran

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Dynamic CMOS are widely employed in high-performance CMOS chips due to high speed and less area in comparison with Static CMOS. However, Dynamic CMOS circuits are inherently less noise tolerant than Static CMOS circuits. This problem becomes more severe with aggressive technology scaling into nanometer process, particularly caused by the charge sharing, the sub-threshold leakage current, the power rail noise and the crosstalk noise. In this thesis, circuit techniques on improving both timing and noise of Dynamic CMOS are presented. A comparison with previous reported work is also presented. Simulations proved that the proposed circuit techniques can achieve a high …

Real-Time Fault Diagnosis Of Automotive Electrical Power Generation And Storage System, Luis Farfan-Ramos

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Automobiles depend more and more on electric power. Analysis of warranty data by automotive OEMs shows that faults in the automotive electrical power generation and storage (EPGS) system are often misdiagnosed. Therefore, monitoring of the state of health (SOH) of the automotive EPGS system is vital for early and correct diagnosis of faults in it, ensuring a reliable supply of electric power to the vehicle and reducing maintenance costs. In this research project, a model-based SOH monitoring method for the EPGS system is developed without the requirement of an alternator current sensor. A model representing the dynamic relationship between the …

Distributed Fault Detection For A Class Of Large-Scale Nonlinear Uncertain Systems, Qi Zhang

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In the distributed large-scale system, the behavior of any subsystem is not only influenced by variables belonging to it (local variables), but also by the variables in other subsystems during its interaction with neighboring subsystems. The effect of the fault in one subsystem will be quickly propagated to other subsystems due to their interconnections. Currently, most of the fault detection and diagnosis schemes are focused on centralized system which do not consider the interaction terms and can not efficiently detect the faults.

In this thesis, a distributed fault detection scheme is developed for a class of large-scale nonlinear uncertain systems …