Digital Commons Network^™

Translation Of Images On The Hypercube Using Leaf Codes, Bhavesh Patel

Theses

Image processing is used for manipulation of pictorial images. Image analysis applications are typically characterized by the need to process large quantities of image data. Some of the important transformations or operations which are car¬ried out by image processing systems are translation, scaling, superposition and rotation. Algorithms have been developed to carry out these transformations on image regions represented by quadtrees. Gargantini introduced an algorithm to translate an image region represented by a linear quadtree or leafcodes. A linear quadtree is a space efficient data structure used for storing digital images. Ziavras et.al. have proposed a modification of Gargantini's algorithm …

Reduction Of Acoustic Feedback Oscillations By Use Of Spectrum Shifting, Youssef Abdelilah

Theses

The problem of whistling noise or self-oscillation in public address systems operating in closed halls or rooms can be very disturbing to the listeners. This noise is sustained when the positive acoustic feedback, of the public address-room system, meets the oscillation criteria. This feedback system results from the acoustic sound signal reflected off the room walls and any other obstacles in the room, originating from the public address speakers and then re-entering the microphone.

When all of the audio signal components entering the public address system are shifted by a frequency increment Δf of 6 Hz, an increase of 5 …

Performance Analysis Of Pyramid Mapping Algorithms For The Hypercube, Jing-Chiou Liou

Theses

Comparative performance analysis of algorithms that map pyramids and multilevel structures onto the hypercube are presented. The pyramid structure is appropriate for low-level and intermediate-level computer vision algorithms. It is not only efficient for the support of both local and global operations but also capable of supporting the implementation of multilevel solvers. Nevertheless, pyramids lack the capability of efficient implementation of the majority of scientific algorithms and their cost may become unacceptably high. On a different horizon, hypercube machines have widely been used in the field of parallel computing due to their small diameter, high degree of fault tolerance, and …

Modal Control Of Flexible Beam Using Smart Mateirals, Sujata Mallepalle

Theses

In this work, the dynamics and control aspects of a vibrating flexible beam using modal analysis are studied. To damp the vibrations of the system, the vibrations of each mode has to he controlled, which can he done if we know the individual mode shape. and the resonance frequency. These quantities can be derived mathematically or measured experimentally with a spectrum analyzer. Individual modal velocities can be computed by integration of the product of beam velocity and the mode shape, over the interval of beam length. The integration is carried out using numerical methods. The necessary discrete ordinates are obtained …

Optimizing Energy Usage In A Solar-Powered Vehicle, William R. Macneil

Opportunities for Undergraduate Research Experience Program (OURE)

The University of Missouri - Rolla (UMR) will be entering SUNRAYCE '93 and the World Solar Challenge and expects to excel in these solar-powered car races. Some of the factors involved in winning a race include efficiency, reliability, and high power. All of these are important considerations, but will be ineffective unless appropriately harnessed by a power management scheme appropriate to a race strategy. The power management scheme will be used to efficiently and effectively distribute available power to the car's systems throughout a race day. My goal was to produce a software framework into which the specifications and performance …

Fiber Optic Fabry-Perot Sensors For Smart Structures, Thomas K. Edmondson

Opportunities for Undergraduate Research Experience Program (OURE)

Optical fiber sensors promise to play a large role in the development of smart structures which have the ability to continuously monitor themselves for internal and external structural deformation, and even actively change shape. This investigation studies one such sensor based on a fiber optic Fabry-Perot interferometer, which detects the displacement between two points of a material. Sensor theory and construction are discussed, and the tools used to analyze sensor output are developed. The interferometer is then tested by attaching it to a large cantilever beam which is deflected to produce strain. This experimental data is then used to determine …

Fiber Optic Microdeformation Sensors For Smart Structures, Lawrence S. Criscione

Opportunities for Undergraduate Research Experience Program (OURE)

When optical fibers are stressed, the deformations at the core-cladding interface induce signal attenuation. Because of their durable physical properties (high melting point) optical fibers can be embedded into certain composite materials at the manufacturing stage. Stresses on the composite induces stresses on the embedded fiber. The amount of stress on the fiber, and thus the stress on the composite, can be determined by measuring the attenuation of a signal passing through the fiber. Force was applied to a single mode and a multimode fiber in a microbend inducing plate, and the attenuation this stress created was measured.

Dynamics Of Ultrashort Pulse Generation And Amplification In Dye Lasers, Shuanghua Jiang

Dissertations and Theses

The dynamics of ultrashort pulse generation and amplification in dye lasers is studied in this dissertation. In particular, we have developed general semiclassical models for ultrashort pulse dye laser amplifiers and oscillators. These models start from Maxwell's equation for the electric field and density matrix equations for the active laser medium. A finite coherence time or phase memory time of the molecular wave functions, a finite vibrational relaxation time for the lower electronic state of the dye laser transition, an isotropic molecular orientational distribution, and an arbitrary pump polarization are all taken into account. Based on these models, specific topics …

Design Of Holographic Optical Interconnections, Su-Chiou Tsay

Theses

Optics have many advantages over electronics in interconnecting systems together, particularly in terms of higher transmission speed and better immunity to noise. Optical interconnections may be used at all levels of computing: for local area networks, between processors or memory elements, and between boards.

In this thesis, we attempted to generate a new type of computer hologram for optical interconnection purposes. The holographic method is very promising whenever integrated optical interconnections are considered. In this research we have tried two designs: the shortest path grating design which can maximize the global output energy and the single input maximum output grating …

A Complexity Analysis Of Smart Pixel Switching Nodes For Photonic Extended Generalized Shuffle Switching Networks, Thomas J. Cloonan, Gaylord W. Richards, Anthony L. Lentine, Frederick B. Mccormick, Harvard Scott Hinton, Stephen J. Hinterlong

Electrical and Computer Engineering Faculty Publications

This paper studies the architectural tradeoffs found in the use of smart pixels for nodes within photonic switching interconnection networks are discussed. The particular networks of interest within the analysis are strictly nonblocking extended generalized shuffle (EGS) networks. Several performance metrics are defined for the analysis, and the effect of node size on these metrics is studied. Optimum node sizes are defined for each of the performance metrics and system-level limitations are identified.

The Anatomy Of Programming Languages, Alice E. Fischer, Frances S. Grodzinsky

Electrical & Computer Engineering and Computer Science Book Series

The specific goals of this book are to help students learn: *To reason clearly about programming languages. *To develop principles of communication so that we can evaluate the wisdom and utility of the decisions made in the process of language design. *To break down language into its major components, and each component in to small pieces so that we can focus on competing alternatives. *To define a consistent and general set of terms for the components out of which programming languages are built, and the concepts on which they are based. * To use these terms to describe existing languages, …

Multiple Quantum-Well Technology Takes Seed, Harvard S. Hinton

Electrical and Computer Engineering Faculty Publications

Progress in the development of self-electrooptic-effect devices (SEEDs) is discussed. The devices include the resistor-SEED (R-SEED) device, which can be viewed as a simple NOR gate. The symmetric SEED (S-SEED) and the logic-SEED (L-SEED) devices with improved features, functionality, and performance are also considered. The integration of FETs with multiple quantum well (MQW) modulators (FET-SEED), enables optical interconnections of electronic circuits. Where the SEED technology can be used is discussed, and an experimental optical switching fabric made using these devices is described.

The Influence Of The Unlocked Characteristics Of A Self-Pulsating Laser Diode On Synchronisation, Gerald Farrell, P. Phelan, Joe Hegarty

Articles

All-optical synchronization and timing extraction based on self-pulsating twin section lasers has been demonstrated. We investigate the variation of the unlocked full-width at- half-maximum of the fundamental of the RF spectrum of a self-pulsating laser diode. We show for the first time that the value of the unlocked FWHM has a direct influence on the power required to maintain synchronization. We also show that the variation of the FWHM with frequency is dependent on the slope of the absorber bias versus self-pulsation frequency characteristic. The results have important implications for the design and selection of self-pulsating laser diodes for synchronization …

Measuring And Compensating For Transport Delay In Real-Time Interactive Driving Simulation, Joseph D. Dumas Ii

Retrospective Theses and Dissertations

Real-time, man-in-the-loop simulators are important tools for operator training as well as human performance research. Simulator implementation using digital computers offers many important advantages but may also cause problems. One of the most significant and troublesome artifacts of digital computer simulation is the presence of transport delays in the operator/vehicle control loop. Transport delays have been shown to destabilize the system, resulting in poorer control of the simulated vehicle. They may also contribute to an increased likelihood of simulator sickness in human operators. Therefore, it is desirable to be able to quantify simulator transport delays and to compensate the system …

Sputter Deposition And Thallination Of Ti-Ba-Ca-Cu-O Superconducting Thin Films, T. H. Dhayagude, S. S. Ang, W. D. Brown

Journal of the Arkansas Academy of Science

Thallination techniques used for the fabrication of sputter-deposited TI2Ba2CaCu 2Ox and TI2Ba2Ca2Cu3Ox superconducting thin films were investigated. Differences in elemental composition of precursor Ba-Ca-Cu-O sputtering targets were found to yield different superconducting phases. Thallination conditions which yielded transition temperatures as high as 122 K for samples annealed in air are described. Finally, reactive ion etching of films using a mixture of chlorine and argon gases is discussed.

Surface Emitting Semiconductor Lasers And Arrays, Gary A. Evans, Jacob M. Hammer

Electrical Engineering Research

No abstract provided.

Analog Chips And Intelligent Vehicles, J. G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

Numerous digital-based sensor systems have been demonstrated on intelligent vehicles but only the most rudimentary experiments have been attempted with analog VLSI chips in real-world environments. The most significant factor in the choice between analog and digital approaches to sensory processing in intelligent vehicles will be the cost of mass production. If analog sensors can be designed with enough speed, resolution and accuracy to solve sensory processing tasks, then the low-cost of mass production ensures that analog circuits will be the technology of choice for future generations of smart sensors. Current analog VLSI sensors do not have enough resolution and …

Lightning Arrester Failure And Ferroresonance On A Distribution System, L. J. Bohmann, J. Mcdaniel, Eldon Keith Stanek

Electrical and Computer Engineering Faculty Research & Creative Works

Since 1987 the Upper Peninsula Power Company (UPPCO) has been experiencing a large number of lightning arrester failures on a portion of their distribution system in southern Marquette County, Michigan. It was in the area of the Navy's Extremely Low Frequency (ELF) antenna where the distribution system had been recently reconfigured so that the transformers were connected line-to-line in order to eliminate interference from the antenna. A study was done which determined that the system was susceptible to ferro resonance during single line faults under lightly loaded conditions and that the overvoltage's experienced could be causing the lightning arrester failures. …

Efficient Simulation Of Multicarrier Digital Communication Systems In Nonlinear Channel Environments, Kevin W. Schneider, William H. Tranter

Electrical and Computer Engineering Faculty Research & Creative Works

The effectiveness of computer simulation as a tool for the design and analysis of communication systems is often limited by the long execution times required for many simulations. When simulating multicarrier digital communication systems operating over nonlinear channels, the required high sampling rate contributes significantly to long execution times. A new method that reduces the sampling rate of simulations of such systems is developed. This Partial Sum of Products (ParSOP) method reduces the sampling rate by generating only the intermodulation products that lie in a frequency band of interest. The ParSOP method requires that the bandpass nonlinearity be represented by …

A Fast Converging, Low Complexity Adaptive Filtering Algorithm, Steven L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

This paper introduces a new adaptive filtering algorithm called fast affine projections (FAP). Its main attributes include RLS (recursive least squares) like convergence and tracking with NLMS (normalized least mean squares) like complexity. This mix of complexity and performance is similar to the recently introduced fast Newton transversal filter (FNTF) algorithm. While FAP shares some similar properties with FNTF it is derived from a different perspective, namely the generalization of the affine projection interpretation of NLMS. FAP relies on a sliding windowed fast RLS (FRLS) algorithm to generate forward and backward prediction vectors and expected prediction error energies. Since sliding …

Faulty Behavior Of Storage Elements And Its Effects On Sequential Circuits, Waleed K. Al-Assadi, Y. K. Malaiya, A. P. Jayasumana

Electrical and Computer Engineering Faculty Research & Creative Works

It is often assumed that the faults in storage elements (SEs) can be modeled as output/input stuck-at faults of the element. They are implicitly considered equivalent to the stuck-at faults in the combinational logic surrounding the SE cells. Transistor-level faults in common SEs are examined here. A more accurate higher level fault model for elementary SEs that better represents the physical failures is presented. It is shown that a minimal (stuck-at) model may be adequate if only modest fault coverage is desired. The enhanced model includes some common fault behaviors of SEs that are not covered by the minimal fault …

Neural Networks In The Former Soviet Union, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

An Optoelectronic Implementation Of The Adaptive Resonance Neural Network, Donald C. Wunsch, T. P. Caudell, R. J. Marks, R. A. Falk, C. David Capps

Electrical and Computer Engineering Faculty Research & Creative Works

A solution to the problem of implementation of the adaptive resonance theory (ART) of neural networks that uses an optical correlator which allows the large body of correlator research to be leveraged in the implementation of ART is presented. The implementation takes advantage of the fact that one ART-based architecture, known as ART1, can be broken into several parts, some of which are better to implement in parallel. The control structure of ART, often regarded as its most complex part, is actually not very time consuming and can be done in electronics. The bottom-up and top-down gated pathways, however, are …

Automatic Color Segmentation Algorithms-With Application To Skin Tumor Feature Identification, Scott E. Umbaugh, Randy Hays Moss, William V. Stoecker, G. A. Hance

Electrical and Computer Engineering Faculty Research & Creative Works

Two color-image segmentation methods are described. The first is based on a spherical coordinate transform of original RGB data. The second is based on a mathematically optimal transform, the principal components transform (also known as eigenvector, discrete Karhunen-Loeve, or Hotelling transform). These algorithms are applied to the extraction from skin tumor images of various features such as tumor border, crust, hair scale, shiny areas, and ulcer. The results of this research will be used in the development of a computer vision system that will serve as the visual front-end of a medical expert system to automate visual feature identification for …

Pump And Signal Cross Saturation In Cw Dye Lasers, Lee W. Casperson, A. C. Wilson, W. J. Sandle

Electrical and Computer Engineering Faculty Publications and Presentations

It is well known that the signal output intensity from a dye laser oscillator depends directly on the pump intensity. The opposite effect, the dependence of the transmitted pump intensity on the signal intensity, is studied in detail. The theoretical results are compared with experimental data obtained using an argon‐laser‐pumped rhodamine 6G dye laser.

An Object-Oriented Computer Aided Design Program For Modern Control Systems Analysis, Frederick L. Trevino

Theses and Dissertations

This investigation is a continuation of the ICECAP-PC research project conducted under Prof. Gary B. Lamont at the Air Force Institute of Technology. It is an ongoing development of a public domain Computer Aided Design (CAD) package for Control Engineering students and faculty, with a special emphasis on education. This investigation focuses on three areas. First, an object-oriented environment is specified, designed and implemented. The functional structure of ICECAP-PC is then converted into an object-oriented structure because object-orientation provides an advanced logic and implementation structure and effectively addresses common software engineering issues. Additionally, a new interface featuring pull-down menus, mouse …

Design And Development Of A High-Speed Winograd Fast Fourier Transform Processor Board, James F. Herron

Theses and Dissertations

Since 1985, the Air Force Institute of Technology has pursued a project to develop a 4080-point Discrete Fourier Transform processor using the Winograd Fourier Transform Algorithm (WFTA) and Good-Thomas Prime Factoring Algorithm (PFA). In the first attempt to build a working system, this research effort designed and constructed, in part, a modified single processor architecture in order to demonstrate the proof of concept of the WFTA system design. This prototype architecture is simpler in implementation but uses the same principles and procedures as those of the 4080-point WFTA design. The design developed in this thesis was validated using the Very …

Automated Control Of Aircraft In Formation Flight, Louis E. Buzogany

Theses and Dissertations

In this study, an automated formation control system for an aircraft formation comprised of one lead and multiple wing aircraft is analyzed. Second- order models of the C-130 aircraft are developed in order to accurately model the flying qualities of large aircraft. This automated formation control system is capable of controlling the C-130 aircraft in maneuvering formation flight, thus reducing the wing's pilot workload. During formation flight, the wing aircraft continuously measures the lead aircraft's relative position with an ideal on-board position sensor. This information, in addition to Proportional Plus Integral feedback control, is used to maintain the aircraft in …

Cepstral And Auditory Model Features For Speaker Recognition, John M. Colombi

Theses and Dissertations

The TIMIT and KING databases, as well as a ten day AFIT speaker corpus, are used to compare proven spectral processing techniques to an auditory neural representation for speaker identification. The feature sets compared were Linear Predictive Coding (LPC) cepstral coefficients and auditory nerve firing rates using the Payton model. This auditory model provides for the mechanisms found in the human middle and inner auditory periphery as well as neural transduction. Clustering algorithms were used to generate speaker specific codebooks - one statistically based and the other a neural approach. These algorithms are the Linde-Buzo-Gray (LBG) algorithm and a Kohonen …

Satcom General Purpose Modem Dscs Iii Sct Beacon Telemetry Display, James D. Coppola

Theses and Dissertations

This thesis documents the design and implementation of a DSCS III single Channel Transponder (SCT) beacon telemetry display. The system is a personal computer based design which interfaces to three SCT beacon receiver/demodulators. The software was designed to decode and display both the DSCS III A and DSCS HI B satellite beacons. Recordings of the SCT beacon display can be made on paper and/or magnetic media when triggered by the user, a watchdog timer, or the SCT command accept telemetry bit. In addition, the system can be configured with an IRIG B Universal Time Coordinates (UTC) card which enables the …