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Application Of A Six-State Passive Track Filter Within A Weapon-Delivery System For A Lock-On-After-Launch Missile, Lynda Jeanne Ciaponi Jan 1991

Application Of A Six-State Passive Track Filter Within A Weapon-Delivery System For A Lock-On-After-Launch Missile, Lynda Jeanne Ciaponi

Retrospective Theses and Dissertations

Knowing the benefits that a passive air target tracking system gives the host aircraft attempting to conceal its own presence on the battlefield, it is desired to determine whether the aircraft can also deliver one of its own lock-on-after-launch air-to-air missiles to the target via use of the same passive system. The objective of this thesis is to demonstrate that a passive six-state track filter can be successfully used within such a weapon delivery system. The role of the filter within the system is to track the enemy target in cartesian space utilizing only line-of-sight measurements and to track the …


Texture Segmentation And Classification Using Fractal And Energy Measures, Qing Chen Jan 1991

Texture Segmentation And Classification Using Fractal And Energy Measures, Qing Chen

Retrospective Theses and Dissertations

This thesis introduces a multi-feature based texture segmentation and classifi­ cation algorithm. We first present general background on segmentation approaches which can be categorized into three groups : characteristic thresholding and clus­ tering, edge detection, and region merging. According to our texture segmentation objective, we choose characteristic thresholding and clustering along with region merging as our segmentation method which is accomplished by a popular K-mean algorithm applied in the feature space. Fractal geometry is receiving increasing attention as a model for natural phe­ nomena. We present an efficient method for estimating the fractal dimension of image surfaces and show that …


Rs170 Image Processing Interface, Charlotte Christou Jan 1991

Rs170 Image Processing Interface, Charlotte Christou

Retrospective Theses and Dissertations

This thesis deals with the hardware design and implementation of an image processing board that digitizes RS-170 video, passes it thru a sobel filter and sends the results to a high-resolution color printer. Most sobels deal with black and white images, but this thesis uses a static color image. The hardware design will allow direct printing from a RGB separate channel RSl 70 video source to a Tektronix 4693DX Color Printer through a Centronics port. It will also allow the red, blue and green video channels to pass through a sobel filter, with the resulting image being sent out to …


Electric Field Induced Emission As A Diagnostic Tool For Measurement Of Local Electric Field Strengths, A. N. Dharamsi, K. H. Schoenbach Jan 1991

Electric Field Induced Emission As A Diagnostic Tool For Measurement Of Local Electric Field Strengths, A. N. Dharamsi, K. H. Schoenbach

Bioelectrics Publications

The phenomenon of electric field induced (EFI) emission is examined in several diatomic and polyatomic molecules. The possibility of using this phenomenon as a diagnostic tool to measure, nonintrusively, the strength and direction of local electric fields in plasmas is discussed. An estimate of the EFI signal emitted in a typical application plasma is given. This yields a lower bound on the detector sensitivity necessary to exploit EFI emission in practical applications. It is concluded that, at present, the EFI signal could be measured by some very sensitive infrared detection schemes available. Current progress in infrared detector technology, if maintained, …


Design Of Robust Controllers For Gas Turbine Engines, D. E. Moellenhoff, Vittal S. Rao, C. A. Skarvan Jan 1991

Design Of Robust Controllers For Gas Turbine Engines, D. E. Moellenhoff, Vittal S. Rao, C. A. Skarvan

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes robust controller design methodologies for gas turbine engines. A linear state variable model for the engine is derived using partial derivatives. The Linear Quadratic Gaussian with Loop Transfer Recovery (LQG/LTR) and the Parameter Robust Linear Quadratic Gaussian (PRLQG) robust controller design methodologies have been used to design a controller for gas turbine engines. A new method is proposed by combining the features of LQG/LTR and PRLQG methods and yields good robustness properties with respect to both unstructured uncertainties in the frequency domain and structured parameter variations in the time domain. The new procedure is illustrated with the …


Error Control Coding For Meteor Burst Communications, Thomas J. Frederick Jan 1991

Error Control Coding For Meteor Burst Communications, Thomas J. Frederick

Retrospective Theses and Dissertations

The phenomenon of meteor burst communications is described and its mathematical model is presented. Protocols for meteors burst systems are outlined and examples are given of current use. Recent research in the area of coding performance in meteor burst systems is pointed out. The performance of several error control coding schemes for a meteor burst channel, including two new adaptive algorithms, are evaluated via analysis and simulation. These coding strategies are compared using the probability of successful transmission of a fixed size packet through a single burst as a performance measure. The coding methods are compared via simulation for several …


An Optoelectronic Adaptive Resonance Unit, Donald C. Wunsch, T. P. Caudell, R. A. Falk, C. David Capps Jan 1991

An Optoelectronic Adaptive Resonance Unit, Donald C. Wunsch, T. P. Caudell, R. A. Falk, C. David Capps

Electrical and Computer Engineering Faculty Research & Creative Works

The authors demonstrate a hardware implementation of the adaptive resonance theory ART 1 neural network architecture. The optoelectronic ART1 unit, is a novel application of an old device. This device-the 4-f or Van der Lugt correlator-has historically been used as a fast pattern classifier. Usually the correlation operation is employed as a matched filter, so that a maximum correlation peak corresponds to a well-matched pattern. The device described also uses the large peaks, but takes specific advantage of the fact that a zero-shift correlation is mathematically equivalent to a two-dimensional inner product. The authors describe a promising method for emulating …


Freeway Control Via Ramp Metering: Development Of A Basic Building Block For An On-Ramp, Discrete, Stochastic, Mesoscopic, Simulation Model Within A Contextual Systems Approach, Mohamed Yaser Alkadri Jan 1991

Freeway Control Via Ramp Metering: Development Of A Basic Building Block For An On-Ramp, Discrete, Stochastic, Mesoscopic, Simulation Model Within A Contextual Systems Approach, Mohamed Yaser Alkadri

Dissertations and Theses

One of the most effective measures of congestion control on freeways has been ramp metering, where vehicle entry to the freeway is regulated by traffic signals (meters). Meters are run with calibrated influx rates to prevent highway saturation. However, recent observations of some metering sites in San Diego, CA indicate that metering, during peak hour demand, is helping freeway flow while sometimes creating considerable traffic back-ups on local streets, transferring congestion problems from the freeway to intersections. Metering problems stem largely from the difficulty of designing an integrated, dynamic metering scheme that responds not only to changing freeway conditions but …


Novel Chemical Preparative Route For Semiconducting Mose2 Thin Films, K. C. Mandal, O. Savadogo Jan 1991

Novel Chemical Preparative Route For Semiconducting Mose2 Thin Films, K. C. Mandal, O. Savadogo

Faculty Publications

No abstract provided.


A Neural Architecture For Unsupervised Learning With Shift, Scale And Rotation Invariance, Efficient Software Simulation Heuristics, And Optoelectronic Implementation, Donald C. Wunsch, D. S. Newman, T. P. Caudell, R. A. Falk, C. David Capps Jan 1991

A Neural Architecture For Unsupervised Learning With Shift, Scale And Rotation Invariance, Efficient Software Simulation Heuristics, And Optoelectronic Implementation, Donald C. Wunsch, D. S. Newman, T. P. Caudell, R. A. Falk, C. David Capps

Electrical and Computer Engineering Faculty Research & Creative Works

A simple modification of the adaptive resonance theory (ART) neural network allows shift, scale and rotation invariant learning. The authors point out that this can be accomplished as a neural architecture by modifying the standard ART with hardwired interconnects that perform a Fourier-Mellin transform, and show how to modify the heuristics for efficient simulation of ART architectures to accomplish the additional innovation. Finally, they discuss the implementation of this in optoelectronic hardware, using a modification of the Van der Lugt optical correlator


Applying Artificial Intelligence To The Identification Of Variegated Coloring In Skin Tumors, Scott E. Umbaugh, Randy Hays Moss, William V. Stoecker Jan 1991

Applying Artificial Intelligence To The Identification Of Variegated Coloring In Skin Tumors, Scott E. Umbaugh, Randy Hays Moss, William V. Stoecker

Electrical and Computer Engineering Faculty Research & Creative Works

The importance of color information for the automatic diagnosis of skin tumors by computer vision is demonstrated. The utility of the relative color concept is proved by the results in identifying variegated coloring. A feature file paradigm is shown to provide an effective methodology for the independent development of software modules for expert system/computer vision research. An automatic induction tool is used effectively to generate rules for identifying variegated coloring. Variegated coloring can be identified at rates as high as 92% when using the automatic induction technique in conjunction with the color segmentation method


Reduced Order H∞ Controller Design, Seng Chu Chow Jan 1991

Reduced Order H∞ Controller Design, Seng Chu Chow

Masters Theses

"The problem formulation and the development of the H∞ optimal control theory are reviewed. Various H∞ robust controller design techniques, including both state and output feedback cases, together with a brief comparison and some remarks on these methodologies arc presented. Also included are a review of the controller order reduction alternatives and various balanced truncation model reduction methods.

A new model reduction technique with reduced error bound is proposed. This proposed technique introduces a new parameter which can be used to select the spectral norm of the model reduction error at low and high frequency ranges according to …


Adaptive Stack Filtering By Lms And Perceptron Learning, Yu-Chou Huang Dec 1990

Adaptive Stack Filtering By Lms And Perceptron Learning, Yu-Chou Huang

Theses

Stack filters are a class of sliding?window nonlinear digital filters that possess the weak superposition property(threshold decomposition) and the ordering property known as the stacking property. They have been demonstrated to be robust in suppressing noise. Two methods are introduced in this thesis to adaptively configure a stack filter. One is by employing the Least Mean Square(LMS) algorithm and the other is based on Perceptron learning.

Experimental results are presented to demonstrate the effectiveness of our methods to noise suppression.


Estimating 3-D Motion And Structure Parameters Of A Rigid Planar Object By Establishing Landmark Correspondences, Herman Agustiawan Dec 1990

Estimating 3-D Motion And Structure Parameters Of A Rigid Planar Object By Establishing Landmark Correspondences, Herman Agustiawan

Theses

The application of a landmark based approach in recognizing 3-D rigid planar objects[3] along with two different motion and structure estimation algorithm [21][23] have been studied to perform motion and structure estimation tasks of moving objects. The recognition algorithm is based on a sphericity value derived from affine transformation that maps feature points in the object under observation from first to second view in the 2-D image space. The motion and structure estimation algorithm is based on a unique mapping given four or more feature point correspondences.

More than ten experiments have been done including small and large rigid motions. …


A Transistor Delay Model Based On Charge Conservation, Bharatsingh K. Bisen Dec 1990

A Transistor Delay Model Based On Charge Conservation, Bharatsingh K. Bisen

Theses

Delay information of a circuit is often used in the areas of timing verification, timing analysis, race detection and circuit optimization. Given a circuit its delay can be estimated by various simulation techniques. SPICE is one of the simulation techniques, but it is seen that with the increase in the complexity of the circuit the SPICE circuit simulation technique to obtain delay information become cumbersome and computationally too expensive. So as to overcome the above disadvantages of the circuit simulation technique to obtain delay information various timing delay models were developed. However general survey of most of these timing delay …


An Investigation Of Optoelectronic Integrated Circuit Receiver, Dinar S. Gupte Dec 1990

An Investigation Of Optoelectronic Integrated Circuit Receiver, Dinar S. Gupte

Theses

This thesis report presents an investigation of an OptoElectronic Integrated receiver Circuit (OEIC). An OEIC on Silicon (Si) substrate is analyzed and simulated as part of this investigation. The OEIC is based on GaAs technology. The advantages of this are its compactness, high speed, low noise and high reliability in light wave communication systems. A higher output signal is required to make such devices suitable for practical applications. This is achieved by the use of a cascode stage. The fabrication techniques of the relevant semiconductor devices have also been discussed.

In light wave communication systems, the region of minimum losses …


Analysis Of Field Distribution Of A Dielectric Resonator And Its Applications, Manohar R. Kamath Dec 1990

Analysis Of Field Distribution Of A Dielectric Resonator And Its Applications, Manohar R. Kamath

Theses

Dielectric resonators (DR) are suitably shaped objects made of high dielectric constant materials like TiO2, BaO, ZnO, and accessory ingredients, which can function as electrical resonators covering a very wide frequency range upto 40GHz. The physical dimensions of dielectric resonators are in mm range. High dielectric constant material resonators seem to be ideally suited for microwave applications because of their miniature size, low loss, insensitivity to magnetic dc biasing fields, and ability to concentrate large RF magnetic fields in small volumes. However temperature stabilization of dielectric resonators is an important consideration as the center frequency is a function …


Electromagnetic Transients Program Interfacing, Enhancement And Comparison With Spice, Siswa Trihadi Dec 1990

Electromagnetic Transients Program Interfacing, Enhancement And Comparison With Spice, Siswa Trihadi

Theses

The Electromagnetic Transients Program (EMTP) is a computer program used to simulate high speed power system transients. The EMTP input data structures and the rules in setting up the input data file are described in this thesis by means of two sample cases i.e an RLC series circuit and a sin le line to ground fault in power system.

The EMTP input data are very detailed an highly-structured column-dependent. To improve the user-friendliness of EMTP by ignoring the difficulty of arranging the column structures, this thesis presents the EM P User Interactive Program. Sample cases using this interactive program are …


Recovering Surface Structure Using Direct Method, Zhu Ying Dec 1990

Recovering Surface Structure Using Direct Method, Zhu Ying

Theses

A new approach to recovering surface structure from a pair of stereo images is proposed in this thesis. The approach is based on an extension of the concept of optical flow to a spatial sequence of images. z.e., the unified optical field (DOFF). A direct method in spatial domain is developed which is able to recover surface structure that can be characterized by an Nth order polynomial equation. The order N of the surface can be one. a planar surface. or two, a cylindrical or spherical surface. for example. or any number higher than two. This is a big improvement …


A Petri Net Simulation Tool, Ashish H. Shukla Dec 1990

A Petri Net Simulation Tool, Ashish H. Shukla

Theses

A user friendly and highly interactive graphical tool for drawing, editing and simulating translated Petri Net models is developed. This SunView based tool allows simulation to be carried out in the 'step' and 'run' modes. In the 'run' mode it produces a log file of the simulation run which consists of: a) total number of tokens in the net; b) names of the transitions that fired; and c) the system state reached after each step's execution. The tool offers a new solution to the problem of modeling concurrent and interlocked systems, such as computer systems, modular software, flexible manufacturing systems …


In Situ Infrared Evidence For The Electrochemical Incorporation Of Hydrogen Into Si And Ge, K. C. Mandal, F. Ozanam, J.-N. Chazalviel Dec 1990

In Situ Infrared Evidence For The Electrochemical Incorporation Of Hydrogen Into Si And Ge, K. C. Mandal, F. Ozanam, J.-N. Chazalviel

Faculty Publications

No abstract provided.


Comparison Of Digital Controllers Used In Magnetic Suspension And Balance Systems, William A. Kilgore Dec 1990

Comparison Of Digital Controllers Used In Magnetic Suspension And Balance Systems, William A. Kilgore

Mechanical & Aerospace Engineering Faculty Publications

Dynamic systems that were once controlled by analog circuits are now controlled by digital computers. Presented is a comparison of the digital controllers presently used with magnetic suspension and balance systems. The overall responses of the systems are compared using a computer simulation of the magnetic suspension and balance system and the digital controllers. The comparisons include responses to both simulated force and position inputs. A preferred digital controller is determined from the simulated responses.


Characterization Of Multilayer Perceptrons And Their Application To Multisensor Automatic Target Detection, Dennis W. Ruck Dec 1990

Characterization Of Multilayer Perceptrons And Their Application To Multisensor Automatic Target Detection, Dennis W. Ruck

Theses and Dissertations

The multilayer perceptron was extensively analyzed. A technique for analyzing the multilayer perceptron, the saliency measure, was developed which provides a measure of the importance of inputs. The method was compared to the conventional statistical technique of best features and shown to provide similar rankings of the input. Using the saliency measure, it is shown that the multilayer perceptron effectively ignores useless inputs and that whether it is trained using backpropagation or extended Kalman filtering, the weighting of the inputs is the same. The backpropagation training algorithm is shown to be a degenerate version of the extended Kalman filter. The …


Speech Coding And Compression Using Wavelets And Lateral Inhibitory Networks, Richard Ricart Dec 1990

Speech Coding And Compression Using Wavelets And Lateral Inhibitory Networks, Richard Ricart

Theses and Dissertations

The purpose of this thesis is to introduce the concept of lateral inhibition as a generalized technique for compressing time/frequency representations of electromagnetic and acoustical signals, particularly speech. This requires at least a rudimentary treatment of the theory of frames-which generalizes most commonly known time/frequency distributions--the biology of hearing, and digital signal processing. As such, this material, along with the interrelationships of the disparate subjects, is presented in a tutorial style. This may leave the mathematician longing for more rigor, the neurophysiological psychologist longing for more substantive support of the hypotheses presented, and the engineer longing for a reprieve from …


Feasibility Analysis Of Developing A Formal Performance Model Of Ada Tasking, Kathryn J. Edwards Dec 1990

Feasibility Analysis Of Developing A Formal Performance Model Of Ada Tasking, Kathryn J. Edwards

Theses and Dissertations

As software system requirements become more complex, software engineers must carefully design the systems to ensure the systems to ensure the systems adequately meet all requirements, both functional and non-functional. Because real-time systems have timing constraints, in addition to the more traditional behavioral constraints, a comprehensive software design analysis model is required which incorporate performance, timing, and behavioral constraints. Although the Ada language tasking constructs are compiler independent, Ada tasking is dependent on its runtime environment; therefore, a formal model of Ada tasking and its associated runtime environment is important in order for system designers to make realistic decisions when …


Digital Control Of The Utah/Mit Dexterous Hand: Initial Evaluation And Analysis, Lloyd W. Rainey Iii Dec 1990

Digital Control Of The Utah/Mit Dexterous Hand: Initial Evaluation And Analysis, Lloyd W. Rainey Iii

Theses and Dissertations

An experimental digital platform is developed as an environment on which to evaluate digital control strategies for dexterous manipulation with a pneumatically actuated tendon-driven manipulator. This environment is used to begin the study of advanced control methods that are suitable for providing the tracking accuracy required for grasping and dexterous manipulation with a pneumatically actuated tendon-driven end-effector. The digital platform consists of a PC/AT-386 and a single board MC68020 microcomputer in a VME chassis with shared RAM between the two processors to control the Utah/MIT Dexterous Hand (UMDH). The MC68020 controls the A/D and D/A access for the UMDH, while …


Oscillation Frequency In High-Gain Lasers, Lee W. Casperson Dec 1990

Oscillation Frequency In High-Gain Lasers, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

The calculation of the oscillation frequency of a single-mode laser oscillator is examined systematically. Mode-pulling formulas are developed for a variety of laser systems, and the limitations of a standard approximation are explored.


Implementation Of The Modified Monte Carlo Technique Using Importance Sampling On The Block Oriented System Simulator, John B. Bennett Dec 1990

Implementation Of The Modified Monte Carlo Technique Using Importance Sampling On The Block Oriented System Simulator, John B. Bennett

Theses and Dissertations

The purpose of this thesis was to implement the Modified Monte Carlo technique using Importance Sampling on the Block Oriented System Simulator (BOSS). Computer simulation techniques of communications systems were reviewed. Next, conventional Monte Carlo techniques and Modified Monte Carlo techniques using Importance Sampling were reviewed. Models of Binary Phase Shift Keying (BPSK) systems using both Monte Carlo techniques were implemented and simulated. Reasons for the model using Importance Sampling not working correctly are postulated. The Monte Carlo technique is a method of ensuring the an inherently infinite procedure, such as determining system bit error rate (BER), can be determined …


The Waveform Relaxation Method For Systems Of Differential/Algebraic Equations, Marija D. Ilić, Mariesa Crow Dec 1990

The Waveform Relaxation Method For Systems Of Differential/Algebraic Equations, Marija D. Ilić, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

An extension of the waveform relaxation (WR) algorithm to systems of differential/algebraic equations (DAE) is presented. Although this type of application has been explored earlier in relation to VLSI circuits, the algorithm has not been generalized to include the vast array of DAE system structures. The solvability and convergence requirements of the WR algorithm for higher-index systems are established. Many systems in robotics and control applications are modeled with DAE systems having an index greater than two. Computer simulation of these systems has been hampered by numerical integration methods which perform poorly and must be explicitly tailored to the system. …


Estimation Of Evoked Fields Using A Time-Sequenced Adaptive Filter With The Modified P-Vector Algorithm, Jeffery A. Kepley Dec 1990

Estimation Of Evoked Fields Using A Time-Sequenced Adaptive Filter With The Modified P-Vector Algorithm, Jeffery A. Kepley

Theses and Dissertations

This thesis describes a time sequenced adaptive filter developed to estimate visually evoked fields (EF) using visually evoked potentials (EP). These non-stationary signals are buried in strong background noise. The two types of noise are magnetoencephalogram (MEG) and electronencephalogram (EEG). The filter implementation is based on the Ferrara Time Sequenced Adaptive (TSAF) using the Least-Mean-Square (LMS) algorithm and the Williams modified P-vector algorithm (mPa). This essentially results in two filters. A two stage filter structure is used in which the first stage removes the time-varying mean of the input signals. This allows the second stage to process zero-mean signals which …