Engineering Commons^™

Short Distance Ground Wave Propagation Modeling In Irregular And Forested Environments, Zachary Michael Crane

Masters Theses

A model for the phase of a ground wave propagating over irregular and forested terrain has been developed and tested for a transmission system operating at 3.315 MHz.

In this model, the time delay induced beyond that of the standard velocity of radio waves in air is modeled as a combination of 3 effects: the finite conductivity of the earth, the irregularity of the terrain over which the wave is propagating, and the forestation of the terrain.

The finite conductivity model is based on a small curvature formula developed by Van Der Pol and Bremmer. The terrain irregularity model models …

Cytongrasp: Cyton Alpha Controller Via Graspit! Simulation, Nicholas Wayne Overfield

Masters Theses

This thesis addresses an expansion of the control programs for the Cyton Alpha 7D 1G arm. The original control system made use of configurable software which exploited the arm’s seven degrees of freedom and kinematic redundancy to control the arm based on desired behaviors that were configured off-line. The inclusions of the GraspIt! grasp planning simulator and toolkit enables the Cyton Alpha to be used in more proactive on-line grasping problems, as well as, presenting many additional tools for on-line learning applications. In short, GraspIt! expands what is possible with the Cyton Alpha to include many machine learning tools and …

Primary User Emulation Attacks In Cognitive Radio - An Experimental Demonstration And Analysis, Benjamin James Ealey

Masters Theses

Cognitive radio networks rely on the ability to avoid primary users, owners of the frequency, and prevent collisions for effective communication to take place. Additional malicious secondary users, jammers, may use a primary user emulation attacks to take advantage of the secondary user's ability to avoid primary users and cause excessive and unexpected disruptions to communications. Two jamming/anti-jamming methods are investigated on Ettus Labs USRP 2 radios. First, pseudo-random channel hopping schemes are implemented for jammers to seek-and-disrupt secondary users while secondary users apply similar schemes to avoid all primary user signatures. In the second method the jammer uses adversarial …

Localized Surface Plasmon Resonance With The Use Of Silver And Titanium Oxide Nanostructures, Charles Wei-Shing Chin

Masters Theses

Light scattering and surface Plasmon calculations were done on a variety of novel geometries using the DDSCAT software package, which simulates the scattering of objects using the discrete dipole approximation method. Calculations were done on core shell nanoparticles consisting of a silver shell and a TiO₂ core in order to determine changes in the extinction spectrum and the near field patterns. Several geometries were tested, including spheres, cylinders, and hexagons, each of varying size and number. It was determined that when geometries were coupled together, there was significant near field enhancement where the geometries were in contact. This enhancement …

Unit Commitment Methods To Accommodate High Levels Of Wind Generation, Alexander Charles Melhorn

Masters Theses

The United State’s renewable portfolio standards call for a large increase of renewable energy and improved conservation efforts over today’s current system. Wind will play a ma jor role in meeting the renewable portfolio standards. As a result, the amount of wind capacity and generation has been growing exponentially over the past 10 to 15 years. The proposed unit commitment method integrates wind energy into a scheduable resource while keeping the formulation simple using mixed integer programming. A reserve constraint is developed and added to unit commitment giving the forecasted wind energy an effective cost. The reserve constraint can be …

Haptic Tele-Operation Of Wheeled Mobile Robot And Unmanned Aerial Vehicle Over The Internet, Zhiyuan Zuo

Masters Theses

Teleoperation of ground/aerial vehicle extends operator's ability (e.g. expertise, strength, mobility) into the remote environment, and haptic feedback enhances the human operator's perception of the slave environment. In my thesis, two cases are studied: wheeled mobile robot (MWR) haptic tele-driving over the Internet and unmanned aerial vehicle (UAV) haptic teleoperation over the Internet.
We propose novel control frameworks for both dynamic WMR and kinematic WMR in various tele-driving modes, and for a "mixed" UAV with translational dynamics and attitude kinematics.
The recently proposed passive set-position modulation (PSPM) framework is extended to guarantee the passivity and/or stability of the closed-loop system …

Pvt Compensation For Single-Slope Measurement Systems, Kevin Vun Kiat Tham

Masters Theses

A pulse-width locked loop (PWLL) circuit is reported that compensates for process, voltage, and temperature (PVT) variations of a linear ramp generator within a 12-bit multi-channel Wilkinson (single-slope integrating) Analog-to-Digital (ADC). This PWLL was designed and fabricated in a 0.5-um Silicon Germanium (SiGe) BiCMOS process. The PWLL architecture that is comprised of a phase detector, a charge-pump, and a pulse width modulator (PWM), is discussed along with the design details of the primary blocks. Simulation and silicon measurement data are shown that demonstrate a large improvement in the accuracy of the PVT-compensated ADC over the uncompensated ADC.

Design Of A High-Voltage, Differential Drive Bradbury-Nielsen Gate Amplifier With Ultra-High Slew Rate And Input Isolation, Kevin Christopher Omoumi

Masters Theses

To isolate and study various components of a nuclear reaction, elaborate equipment must be developed to aid in this process. This thesis presents the design and implementation of an ultra-high slew rate Bradbury-Nielsen gate driver circuit with high-voltage input isolation. This design will be used in a multi-pass time-of-flight isomer spectrometer and separator application integrated into an overall instrument called the Oak Ridge Isomer Spectrometer and Separator (ORISS). The output drive signals of this circuit are transmitted through a vacuum feed-through system to supply the necessary signals to the Bradbury-Nielsen gate contained within the vacuum. A differential driving signal with …

Thermal Feasibility And Performance Characteristics Of An Air-Cooled Axial Flow Cylindrical Power Inverter By Finite Element Analysis, Jonathan Atef Tawfik

Masters Theses

The purpose of the present study is to determine the thermal feasibility of an air-cooled power inverter. The inverter circuitry layout is designed in tandem with the thermal management of the devices. The cylindrical configuration of the air-cooled inverter concept accommodates a collinear axial air blower and a cylindrical capacitor with inverter cards oriented radially between them. Cooling air flows from the axial fan around the inverter cards and through the center hole of the cylindrical capacitor. The present study is a continuation of the thermal feasibility study conducted in fiscal year 2009 for the Oak Ridge National Laboratory to …

Software Verification For A Custom Instrument Using Vectorcast And Codesonar, Christina Dawn Ward

Masters Theses

The goal of this thesis is to apply a structured verification process to a software package using a set of commercially available verification tools. The software package to be verified is adapted from a project that was developed to monitor an industrial machine at the Oak Ridge National Laboratory and includes two major subsystems. One subsystem, referred to as the Industrial Machine Monitoring Instrument (IMMI), connects to a machine and monitors operating parameters using common industrial sensors. A second subsystem, referred to as the Distributed Control System (DCS), interfaces between the IMMI and a personal computer, which provides a human …

Gpu-Based Implementation Of The Variational Path Integral Method, Shanthan Mudhasani

Masters Theses

Any system in the world constitutes particles like electrons. To analyze the behaviors of these systems the behavior of these particles must be predicted. The ground state energy of a molecule is the most important information about a molecule and can calculate by solving the Schrodinger equation. But as the number of atoms increase, the number of variable (coordinates of the atom) that the equation represent increases by three times. Due to the large state space and the nonlinear nature of the Schrodinger equation, it is very difficult to solver this equation. Quantum Monte Carlo (QMC) is a very efficient …

Low Power Design Of A 916 Mhz Gilbert Cell Mixer And A Class-A Power Amplifier For Bioluminescent Bioreporter Integrated Circuit Transmitter, Supriya Kilambi

Masters Theses

This thesis presents the low power design of a 916MHz Gilbert cell mixer and a Class-A power amplifier for the Bioluminescent Bioreporter Integrated Circuit (BBIC) transmitter.

There has been increased use in the man-made sensors which can operate in environments unsuitable for humans and at locations remote from the observer. One such sensor is the bioluminescent bioreporter integrated circuit (BBIC). Bioluminescent bioreporters are the bacteria that are genetically engineered in order to achieve bioluminescence when in contact with the target substance. The BBIC has bioreporters placed on a single CMOS integrated circuit (IC) that detects the bioluminescence, performs the signal …

Classification System For Impedance Spectra, Carl Gordon Sapp

Masters Theses

This thesis documents research, methods, and results to satisfy the requirements for the M.S. degree in Electrical Engineering at the University of Tennessee. This thesis explores two primary steps for proper classification of impedance spectra: data dimension reduction and effectiveness of similarity/dissimilarity measure comparison in classification. To understand the data characteristics and classification thresholds, a circuit model analysis for simulation and unclassifiable determination is studied. The research is conducted using previously collected data of complex valued impedance measurements taken from 1844 similar devices. The results show a classification system capable of proper classification of 99% of data samples with well-separated …

Design Of A Conditioner For Smoothing Wind Turbine Output Power, Murali Bottu

Masters Theses

"As a result of wind speed intermittency, wind turbine output power can be highly variable. The large variability in output power can adversely impact local loads that are sensitive to pulsating power. To mitigate large swings in power, the wind turbine output power can be smoothed by using a small energy buffer. A power conditioner is proposed to smooth the wind power output by utilizing the energy of an ultracapacitor. The conditioner is based on a single phase voltage source inverter (VSI) connected between the grid interconnection point and the ultracapacitor. The shunt VSI injects or absorbs active power from …

Towards On-Line Voltage Stability Assessment Using Synchrophasors, Himanshu Subandhu Hirlekar

Masters Theses

"Voltage instability has become a growing concern in the operation of power systems in recent years. The reason is that power systems all over are being operated with reduced margins because of increased demand exacerbated by a general reluctance to invest in improvement of the electric grid infrastructure. Until recently it was difficult to predict voltage instability in the on-line environment. However, advances in technology has made possible the on-line monitoring and assessment of voltage stability. Synchrophasors is a relatively new technology in the field of power systems which allows system operators to monitor the system conditions at specific measurement …

Rapid Simulation Of The Statistical Variation Of Crosstalk In Cable Harness Bundles, Xiang Li

Masters Theses

"Accurate assessment of crosstalk problems in cable harnesses requires simulation methods that account for the statistical variation of harness parameters. Methods are proposed to determine the influence of the statistical variation in wire positions, the rate that wires change position (i.e. "twist"), harness height, harness density (i.e. how closely wires are packed) and circuit loads. Methods use a combination of simulation and probability theory. Simulations use the T-parameter method, a rapid simulation technique for harness bundles. Simulation time is further improved by using the mean and variance of crosstalk estimated for fixed harness parameter values to estimate the mean and …

Impact Of Channel Statistics And Correlation On Underwater Acoustic Communication Systems, Jesse Scott Cross

Masters Theses

"Several statistical properties of underwater acoustic channels gathered from experiment data are analyzed. The baseband channel impulse response (CIR) is estimated using a time domain least squares technique with a sliding window applied to the probing sequences. From the CIR estimation, the probability distribution functions (PDFs) of the magnitude, real part, imaginary part, and phase of the CIR are calculated. Gamma, Rayleigh, and compound k distributions are fitted to the magnitude PDF and the fitness of the distributions are calculated with a two-sample Kolmogorov-Smirnov test. Other statistics such as the autocorrelation function, coherence time, and scattering function are evaluated. The …

Simulink As A Tool For Modelling Communication Systems, Chaitri Avinash Aroskar

Masters Theses

"Simulink is a graphical tool provided by MathWorks to enable model-based design and simulation. This thesis consists of two papers which take advantage of Simulink features in order to model communication systems.

The first paper employs Simulink to create projects to supplement a purely lecture oriented course: Communication Systems I. The projects cover Linear systems, Analog modulation and Digital modulation concepts in a set of six projects. These projects have been designed based on Gagne's nine events of instruction to enhance their impact on students' learning process. The paper also outlines the advantages of this approach over the conventional programming …

Quantitative Oxygen Imaging With A Display Screen And A Color Camera, Sanghan Park

Masters Theses

"Optical oxygen sensing uses luminophores such as metal complex dyes that respond to oxygen when illuminated by their specific excitation wavelengths. Traditional optical instruments are mostly spectrometric instruments based on the measurements of emission, absorption or reflection. There is, however, a great need to develop simple, economical, photometric detection components toward quantitative and two-dimensional imaging instruments.

In this work, familiar optoelectronic devices were utilized to demonstrate a simple determination method of gaseous oxygen both quantitatively and qualitatively. A liquid crystal display (LCD) screen and a color charge-coupled device (CCD) camera were employed as a light source for fluorescence excitation and …

Model Based Diagnostics And Prognostics Of Practical Industrial Systems, Raja Sekhar Kraleti

Masters Theses

"In this thesis, the diagnosis and prognosis of single and simultaneous multiple incipient faults in practical industrial systems is demonstrated in two papers. For the purpose of fault detection and failure prediction, a model based strategy is adopted, which involves using an online adaptive estimator. The online estimator estimates the system dynamics. Residual is generated based on the physical system model and the estimated system dynamics. This residual is used to detect the fault. Once the fault is detected, a tunable nonlinear neural network online approximator in discrete-time (OLAD) along with a robust adaptive term is initiated. The OLAD utilizes …

Educational Robotics: Using The Lego Mindstorms Nxt Platform For Increasing High School Stem Education, Matthew Aaron Strautmann

Masters Theses

"The field of educational robotics (ER) seeks to use the building and programming of robots to engage and educate the next generation of college freshman entering science and engineering majors. To increase the rate of application to science and engineering degree programs as well as the rate of retention, students must be engaged in high school. They must acquire the knowledge and interest to pursue these career choices. This research explores the use of robotics to interest high school students in science, technology, engineering, and math (STEM) and to improve their knowledge of these subjects. The case study developed instructional …

Development Of A Graphical User Interface For The Study Of Parallel-Connected Solar Arrays, Nisha Nagarajan

Masters Theses

"For any solar array it is necessary to be able to harness the maximum possible power from it. A new technology is proposed to improve the efficiency of solar arrays and harness maximum potential power as well by connecting the solar panels in parallel. This thesis describes the development of a graphical user interface for the evaluation of this parallel-connected solar array technology and to compare different scenarios for solar arrays to predict the potential power output to decide the best configuration for an application. This is done via several computations and analysis of field data. The first paper describes …

Optimal Control Of A Helicopter Unmanned Aerial Vehicle (Uav), David John Nodland

Masters Theses

"This thesis addresses optimal control of a helicopter unmanned aerial vehicle (UAV). Helicopter UAVs may be widely used for both military and civilian operations. Because these helicopters are underactuated nonlinear mechanical systems, high-performance controller design for them presents a challenge. This thesis presents an optimal controller design via both state and output feedback for trajectory tracking of a helicopter UAV using a neural network (NN). The state and output-feedback control system utilizes the backstepping methodology, employing kinematic and dynamic controllers while the output feedback approach uses an observer in addition to these controllers. The online approximator-based dynamic controller learns the …

Design Of A Current Probe For Measuring Ball-Grid-Array Packaged Devices, Tianqi Li

Masters Theses

"A current probe to measure BGA ball currents via magnetic induction has been designed. The probe is manufactured on a 4 layer flex circuit and has been validated by full wave simulations and measurements. The feature size of the probe is very tiny that it almost pushes the limit of flex-circuit technology. Several critical manufacturing problems were happened, and they have been solved now. The probe allows measuring currents of a 1 mm pitch BGA ball directly. Its operating frequency stretched from tens of MHz up to 3GHz. The BGA probe's mutual inductance is approximately 11 pH, and with amplifiers …

Microcontroller-Based Multiple-Input Multiple-Output Transmitter Systems, Balaji Madapuci Kanday

Masters Theses

"Multiple-Input Multiple_output (MIMO) Systems use multiple antennas at both the transmitter and receiver to increase data throughput and/or system reliability. An MIMO transmitter can be implemented using a variety of approaches. This work describes some of the approaches that can be used to generate the transmitted waveforms, and discuss the features and limitation of each. In particular, it shows haw a microcontroller-based system can be used for applications which require low power consumption. This thesis also describes the high-level design of a microcontroller-based MIMO transmitter. The computational speed of the microcontroller, as compared to Field-programmable Gate Array (FPGA) and Digital …

A Rapid-Acquisition Electrical Time-Domain Reflectometer For Analysis Of Time-Variant Impedance Discontinuities, Joseph Andrew Bishop

Masters Theses

"A distributed crack sensor has been developed for the measurement of cracks in concrete structures. The sensor is measured using a distributed measurement technique known as electrical time-domain reflectometry (ETDR). ETDR has traditionally been used to measure time-invariant (i.e. unchanging with time) impedance discontinuities, however applications of the sensor in structural failure analysis require measurement of time-variant (i.e. changing with time) impedance discontinuities at rates as high as 10 k measurements per second. ETDR is a suitable measurement technique for these applications since a time-domain reflectometer (TDR) acquisition can be performed in less than 100 µs. Employment of ETDR in …

Intelligent Control Of Smartparks And Wind Farms In Smart Grids, Priyam Chakravarty

Masters Theses

"With development in wind turbine technology, wind energy has become an important contestant in the utility market. However, wind energy has the intrinsic property of variations which causes fluctuations in the power grid.

Plug-in electric vehicles are drawing the attention of researchers and the electric power industry because of its need for charging from the grid and its ability to store energy. With increase in the numbers of plug-in electric vehicles, there will be significant penetration of distributed energy resources and hence plug-in electric vehicles connected to the grid in parking lots (SmartParks) can be used as energy storage sink …

Comparison Of Matrix Pencil And Prony Analysis For Estimating Electromechanical Modes In Noisy Signals For Power System Applications, Lisa L. Grant

Masters Theses

"As modern power systems continue to grow and evolve, accurate system stability analysis and oscillation control become increasingly important to guarantee system security. Network instability due to power system oscillations caused by the natural modes of the system is becoming a common occurrence. Modal analysis techniques can estimate the eigenvalues of large nonlinear systems from their dynamics responses. The extracted modal information can be applied to detect low frequency oscillations and assess stability margins for power system monitoring and preventive control. Modal information is also useful for low-frequency oscillation damping controller design. This thesis examines two techniques for modal identification …

Multiple-Input Multiple-Output System Simulation For Spinning Vehicles, Samuel James Petersen

Masters Theses

"This paper investigates the performance of a multiple-input multiple-output (MIMO) wireless communication system, when the transmitter is located on a spinning vehicle. In particular, a 2x2 MIMO system is used, with Alamouti coding at the transmitter. Both Rayleigh and Rician statistical models are considered in this paper and are combined with a deterministic spinning model to simulate the channel. The spinning of the transmitting vehicle, relative to the stationary receive antennas causes additional signal fading, and complicates the decoding and channel estimation. The simulated bit error rate is the primary performance metric used. A 4x2 asymmetric Alamouti coding scheme is …

Mutual Attraction Guided Search: A Novel Solution Method To The Traveling Salesman Problem With Vehicle Dynamics, Jared Adam Nisbett

Masters Theses

"Traveling Salesman Problem (TSP) solution techniques are often used for route planning for automated vehicles. Most TSP solution methods focus on path length as the fitness reference, however in many cases, traversal time is of more practical importance. Mutual Attraction Guided Search (MAGS) is a novel solution method that uses an iterative process to simultaneously optimize both angle of travel through each target as well as the ordering of the targets in order to optimize path traversal time. MAGS deterministically locates a locally optimum solution quickly and can optimize for the acceleration limits of a specific vehicle rather than requiring …