Engineering Commons^™

Electro-Luminescent Area Illumination Device, Michael E. Miller, Ronald S. Cok

AFIT Patents

An electro-luminescent area illumination device that includes two or more area emitters formed on a substrate. Each of the two or more area emitters emit light having different area illumination profiles.

Kreative Outlets, Travis Crist, Steve Clark, Jason Peressini

Computer Engineering

With the widespread use of smart phones and the advancement of WiFi technologies, people now have the Internet at their fingertips at all times. Home automation and control has the possibility of becoming the next big technology that can utilize the abundant availability of the Internet. This paper documents the findings and results of a project aimed at developing the infrastructure needed for a home automation system that is accessible anywhere. We implemented a system that utilized a web enabled ethernet connection and RF wireless technology to control AC outlets and provide the user with feedback information about the status …

Car Alarm System, David Lane

Electrical Engineering

This project entails the design and implementation of a car alarm system for a 1977 Volkswagen Beetle.

Rapid Battery Interchange System, Mason Borda

Electrical Engineering

As our nation strives towards a departure from widespread use of fossil fuels, we must focus on a plan for what is to be the substitute for Internal Combustion Engine vehicles as well as the infrastructure to support this. The most popular alternative to the internal combustion engine is the electrically propelled vehicle, one that can provide us with many benefits including simplified construction, lower operational costs, and for the driving enthusiasts more torque. The prevailing issue in the widespread acceptance and use of the electric vehicle thus far is “range anxiety”. Range anxiety is defined as “The fear of …

Determining The Maximum Or Minimum Impedance Of A Special Parallel Rlc Circuit Without Calculus, Kenneth V. Cartwright, Edit J. Kaminsky

Electrical Engineering Faculty Publications

We show that the maximum or minimum impedance of a special parallel RLC studied in a previous paper can be found analytically, without using calculus. In fact, we show that the maximum or minimum value occurs when the driving frequency  is equal to o 1/ LC , a fact that was determined graphically in that previous paper. Furthermore, we show that either the maximum or minimum value is given by     2 2 R  1  3 ,where   L/C / R. Also, for the minimum impedance   2 min Z  R …

Sparsening Filter Design For Iterative Soft-Input Soft-Output Detectors, Raquel G. Machado, Andrew G. Klein, Richard K. Martin

Faculty Publications

A large body of research exists around the idea of channel shortening, where a prefilter is designed to reduce the effective channel impulse response to some smaller number of contiguous taps. This idea was originally conceived to reduce the complexity of Viterbi-based maximum-likelihood equalizers. Here, we consider a generalization of channel shortening which we term "channel sparsening". In this case, a prefilter is designed to reduce the effective channel to a small number of nonzero taps which do not need to be contiguous. When used in combination with belief-propagation-based maximum a posteriori (MAP) detectors, an analogous complexity reduction can be …

Development Of Smart Pv Inverters For The Smart Grid, Yahia Baghzouz

NSTec UNLV Symposium

The Electric Grid has become more complex with recent technological developments. There are more alternative power sources and sensors added into the mix at every part of the grid. The Energy Meter has changed over the past several years as well. The older meters were checked only once a month with a meter reader, but the new "Smart" Meters are capable of reporting energy usage at fifteen minute intervals.

Electroluminescent Area Illumination With Integrated Mechanical Switch, Ronald S. Cok, Michael E. Miller

AFIT Patents

An electroluminescent lam including a lamp substrate; a first electrode formed over the lamp substrate device side, one or more layers having light-emitting material formed over the first electrode, and a second electrode formed over the one or more layers, a chiplet having a chiplet substrate separate and independent from the lamp substrate and adhered to the lamp substrate device side, one or more connection pads, a mechanical switch, and a control circuit for controlling the mechanical switch, the mechanical switch electrically connected to one or more connection pads and at least one connection pad electrically connected to the first …

Polar Field Oriented Control With 3rd Harmonic Injection, Martin Todd Hess

Master's Theses

Abstract

POLAR FIELD-ORIENTED CONTROL

with

3^RD HARMONIC INJECTION

Martin Todd Hess

Field Oriented Control (FOC), also known as vector control, is a widely used and well documented method for controlling Permanent-Magnet Synchronous Motors (PMSM) and induction motors. Almost invariably the orientation of the stator and rotor (field) fluxes are described in rectangular coordinates. In this thesis we explore the practicality of using polar coordinates.

Third harmonic injection is also a well-known technique that allows full utilization of the bus (DC-link), thus allowing the motor to run to full base speed without the use of field weakening. This technique potentially …

Characterising Domestic Electricity Consumption Patterns By Dwelling And Occupant Socio-Economic Variables: An Irish Case Study, Fintan Mcloughlin, Aidan Duffy, Michael Conlon

Articles

This paper examines the influence of dwelling and occupant characteristics on domestic electricity consumption patterns by analysing data obtained from a smart metering survey of a representative cross section of approximately 4,200 domestic Irish dwellings. A multiple linear regression model was applied to four parameters: total electricity consumption, maximum demand, load factor and time of use (ToU) of maximum electricity demand for a number of different dwelling and occupant socio-economic variables. In particular, dwelling type, number of bedrooms, head of household (HoH) age, household composition, social class, water heating and cooking type all had a significant influence over total domestic …

Source Localization Via Time Difference Of Arrival, Ciprian Romeo Comsa

Dissertations

Accurate localization of a signal source, based on the signals collected by a number of receiving sensors deployed in the source surrounding area is a problem of interest in various fields. This dissertation aims at exploring different techniques to improve the localization accuracy of non-cooperative sources, i.e., sources for which the specific transmitted symbols and the time of the transmitted signal are unknown to the receiving sensors. With the localization of non-cooperative sources, time difference of arrival (TDOA) of the signals received at pairs of sensors is typically employed.

A two-stage localization method in multipath environments is proposed. During the …

Target Localization In Passive And Active Systems : Performance Bonds, Vlad Mihai Chiriac

Dissertations

The main goal of this dissertation is to improve the understanding and to develop ways to predict the performance of localization techniques as a function of signal-to-noise ratio (SNR) and of system parameters. To this end, lower bounds on the maximum likelihood estimator (MLE) performance are studied. The Cramer-Rao lower bound (CRLB) for coherent passive localization of a near-field source is derived. It is shown through the Cramer-Rao bound that, the coherent localization systems can provide high accuracies in localization, to the order of carrier frequency of the observed signal. High accuracies come to a price of having a highly …

High Rate Space Time Code With Linear Decoding Complexity For Multiple Transmitting Antennas, Amir Laufer

Dissertations

The multipath nature of the wireless channel, results in a superposition of the signals of each path at the receiver. This can lead to either constructive or destructive interference. Strong destructive interference is frequently referred to as deep fade and may result in temporary failure of communication due to the severe drop in the channel's signal-to-noise ratio (SNR). To avoid this situation, signal diversity might be introduced. When having more than one antenna at the transmitter and / or receiver, forming a Multiple-Input Multiple-Output (MIMO) channel, spatial diversity can be employed to overcome the fading problem. Space time block codes …

Influence Of Defects And Impurities On Solar Cell Performance, Vinay Budhraja

Dissertations

Multicrystalline silicon (mc-Si) solar cells exhibit high impurity content and higher density of crystal defects such as grain boundaries, dislocations, stacking faults and impurity precipitates. Even though the effect of dislocations on mc-Si solar cell performance has been studied, a severe lack of understanding of the quantitative effects of dislocations on cell parameters still exists. Some correlation has been reported under the assumption of a uniform distribution of dislocation density and a negligible effect of front and back surface recombination velocity. This assumption can cause a significant error as the current mc-Si technology provides good surface passivation by SiN:H and …

Wireless Sensor Network For Health Monitoring, Jin Soo Choi

Dissertations

Wireless Sensor Network (WSN) is becoming a significant enabling technology for a wide variety of applications. Recent advances in WSN have facilitated the realization of pervasive health monitoring for both homecare and hospital environments. Current technological advances in sensors, power-efficient integrated circuits, and wireless communication have allowed the development of miniature, lightweight, low-cost, and smart physiological sensor nodes. These nodes are capable of sensing, processing, and communicating one or more vital signs. Furthermore, they can be used in wireless personal area networks (WPANs) or wireless body sensor networks (WBSNs) for health monitoring. Many studies were performed and/or are under way …

Analysis Of A Composite Dielectric-Ferrite Loaded Resonator Using The Transmission Line Model With Application To A Tunable Dual Mode Bandpass Filter, Charlotte Blair

Dissertations

A magnetically tuned filter is presented in this dissertation. Filter tuning of a dielectric ceramic resonator is accomplished using by using two oppositely biased ferrites. Specifically, a change in the applied magnetic field is used to alter the permeability of the ferrite so as to achieve maximum tuning range. Through electromagnetic (EM) simulations and laboratory experiments, tuning of the filter passband by 20 MHz is demonstrated.

This investigation focuses on the design of a bandpass resonator using a combination of dielectric-ferrite material layers. An initial simplification of the geometry of the structure is used as the basis for a program …

Trust Management Schemes For Peer-To-Peer Networks, Lin Cai

Dissertations

Peer-to-peer (P2P) networking enables users with similar interests to exchange, or obtain files. This network model has been proven popular to exchange music, pictures, or software applications. These files are saved, and most likely executed, at the downloading host. At the expense of this mechanism, worms, viruses, and malware find an open front door to the downloading host and gives them a convenient environment for successful proliferation throughout the network. Although virus detection software is currently available, this countermeasure works in a reactive fashion, and in most times, in an isolated manner. A trust management scheme is considered to contain …

Distributed Spectrum Leasing Via Cooperation, Tariq Elkourdi

Dissertations

“Cognitive radio” networks enable the coexistence of primary (licensed) and secondary (unlicensed) terminals. Conventional frameworks, namely commons and property-rights models, while being promising in certain aspects, appear to have significant drawbacks for implementation of large-scale distributed cognitive radio networks, due to the technological and theoretical limits on the ability of secondary activity to perform effective spectrum sensing and on the stringent constraints on protocols and architectures.

To address the problems highlighted above, the framework of distributed spectrum leasing via cross-layer cooperation (DiSC) has been recently proposed as a basic mechanism to guide the design of decentralized cognitive radio networks. According …

Analysis And Mitigation Of Carrier Frequency Offset For Uplink Of Ofdma, Abhishek R. Panchal

Theses

Orthogonal Frequency Division Multiplexing (OFDM) is being used in many wireless standards because of its immunity to multipath fading, high spectral efficiency and simple implementation, making it suitable for high data rate multimedia wireless applications. One of the significant drawbacks of the OFDM is its sensitivity to Carrier Frequency Offset (CFO). CFO causes Inter Carrier Interference (ICI) between subcarriers and Multiple User Interference (MUI) at Uplink between different users. ICI and MUI at uplink cause significant degradation in the performance of the receiver, therefore, to improve the receiver performance up to acceptable level, compensation of the CFO becomes necessary.

In …

Single-Carrier Frequency Domain Equalization Using Subband Decomposition For Optical Wireless Communications, Di Mu

Theses

Optical wireless communication is intended to be applied into indoor and visual distance high-rate data transmission, which is complementary to radio frequency communications. There are specific problems and requirements in optical wireless communications compared with radio frequency communications. Single-carrier frequency domain equalization (SCFDE) is a transmission scheme which has been considered as an alternative of orthogonal frequency-division multiplexing (OFDM), because it has most of the advantages of OFDM and avoids the problems of OFDM. Subband decomposition is a multi-resolution signal analysis and synthesis method, using quadrature mirror filter (QMF) bank to convert time-domain signal to frequency-domain subbands. As a time-to-frequency …

Dynamic Friction: Measurement And Results, Yanal Jij

Theses

Friction has been known as a phenomenon since Leonardo da Vinci era. From that time and through the last four centuries, scientists tried to understand this phenomenon in an effort to overcome its undesired side effects which include energy loss, parts wearing, and errors in control systems. Much has been achieved in studying friction and many experiments have been conducted in this field. These experiments resulted in a mounting evidence that friction is a dynamic phenomenon.

This thesis presents an apparatus that measures dynamic friction in linear motion and the results obtained using this apparatus. The apparatus consists of a …

Temperature Dependence Of Current Conduction In Semi-Insulating 4h-Sic Epitaxial Layer, P. G. Muzykov, Ramesh Madhu Krishna, K. C. Mandal

Faculty Publications

No abstract provided.

Method For Converting An Input Color Signal, Ronald S. Cok, Michael E. Miller

AFIT Patents

A white light-emitting microcavity light-emitting diode device, comprising a method for converting a red, green, and blue (RGB) input signal to a converted signal having RGB color signals and an additional saturated color signal, by calculating saturation of the additional saturated color in the RGB input signal to determine the proportion of the additional saturated color signal to the sum of the converted RGB color signals such that the proportion of the additional saturated color signal is constant or decreases as the saturation of the additional color in the RGB input signal increases.

Stereoscopic Display System With Flexible Rendering Of Disparity Map According To The Stereoscopic Fusing Capability Of The Observer, Elaine W. Jin, Michael E. Miller, Serguei Endrikhovski, Cathleen D. Cerosaletti

AFIT Patents

A method is provided for customizing scene content, according to a user or a cluster of users, for a given stereoscopic display, including obtaining customization information about the user; obtaining a scene disparity map for a pair of given stereo images and/or a three-dimensional (3D) computer graphic model; and determining an aim disparity range for the user. The method of the present invention also generates a customized disparity map and/or rendering conditions for a three-dimensional (3D) computer graphic model correlating with the user's fusing capability of the given stereoscopic display; and renders or re-renders the stereo images for subsequent display.

A Threshold-Based Approach To Calorimetry In Helium Droplets: Measurement Of Binding Energies Of Water Clusters, William K. Lewis, Barbara A. Harruff-Miller, Michael A. Gord, Joseph R. Gord, Elena A. Guliants, Christopher E. Bunker

Electrical and Computer Engineering Faculty Publications

Helium dropletbeam methods have emerged as a versatile technique that can be used to assemble a wide variety of atomic and molecular clusters. We have developed a method to measure the binding energies of clusters assembled in helium droplets by determining the minimum droplet sizes required to assemble and detect selected clusters in the spectrum of the dopeddropletbeam. The differences in the droplet sizes required between the various multimers are then used to estimate the incremental binding energies. We have applied this method to measure the binding energies of cyclic waterclusters from the dimer to the tetramer. We obtain measured …

The Bit Error Rate (Ber) Performance In Multi-Carrier (Ofdm) And Single-Carrier, Saleh M. Albdran

Electronic Theses and Dissertations

The spectacular growth of wireless communication tools has escalated the number of mobile subscribers from almost 700 million in 2000 to more than 4 billion in 2009. The huge number of subscribers has led to several issues with how service is provided. The high user demand has forced developers to overcome the problems of the old analog systems and to introduce OFDM as a promising technique that can fulfill users' high demands. This technique matches well with high data rate connection and provides a higher capacity for the subscribers' usage.

The OFDM, as a multi-carrier, is more complex than the …

Electrically Tunable Fabry-Perot Resonator Based On Microstructured Si Contaning Liquid Crystal, V. A. Tolmachev, V. A. Melnikov, A. V. Baldycheva, Kevin Berwick, T. S. Perova

Articles

We have built Fabry-Pérot resonators based on microstructured silicon and a liquid crystal. The devices exhibit tuning of the resonance peaks over a wide range, with relative spectral shifts of up to Δλ/λ = 10%. In order to achieve this substantial spectral shift, cavity peaks of high order were used. Under applied voltages of up to 15 V, a variation in the refractive index of the nematic liquid crystal E7 from Δn_LC = 0.12 to Δn_LC = 0.17 was observed. These results may have practical applications in the near-, mid and far-infrared range.

Surface Acoustic Wave (Saw) Cryogenic Liquid And Hydrogen Gas Sensors, Brian Fisher

Electronic Theses and Dissertations

This research was born from NASA Kennedy Space Center’s (KSC) need for passive, wireless and individually distinguishable cryogenic liquid and H2 gas sensors in various facilities. The risks of catastrophic accidents, associated with the storage and use of cryogenic fluids may be minimized by constant monitoring. Accidents involving the release of H2 gas or LH2 were responsible for 81% of total accidents in the aerospace industry. These problems may be mitigated by the implementation of a passive (or low-power), wireless, gas detection system, which continuously monitors multiple nodes and reports temperature and H2 gas presence. Passive, wireless, cryogenic liquid level …

Variance In Fade-Time Of A Gamma-Gamma Distributed Irradiance Signal, Troy T. Leclerc

Electronic Theses and Dissertations

Free-space optical communications are predominantly hindered by optical turbulence, an effect caused by temperature and pressure variations within the atmosphere. The result is an optical wave interfering with itself due to multipath propagation via tiny refractive-index fluctuations across the wave-front. Optical communication systems are affected when the channel conditions induce fading in the irradiance signal that is received at the detector. The nature of optical interference imparted by the atmosphere is a random process and therefore the received irradiance signal is often characterized by an appropriate probability density function (PDF). Data collected during past free-space optical experiments in the atmosphere …

Synchronous Communication System For Saw Sensors Interrogation, Maxim Troshin

Electronic Theses and Dissertations

During past two decades a variety of SAW based wireless sensors were invented and research is still in progress. As different frequencies, varied bandwidths, coding techniques and constantly changing post processing algorithms are being implemented, there is a constant need for a universal and adjustable synchronous communication system able to interrogate new generations of SAW sensors. This thesis presents the design of a multiple FPGA based communication system with an operational frequency range of 450MHz-2.2GHz capable of producing user programmed modulated signal. The synchronous receiver is designed to have interchangeable chip, replacement of which would allow adjustment of the receiver’s …