Digital Commons Network^™

Investigation Of Fundamental Emi Source Mechanisms Driving Common-Mode Radiation From Printed Circuit Boards With Attached Cables, David M. Hockanson, James L. Drewniak, Todd H. Hubing, Thomas Van Doren, Fei Sha, Michael J. Wilhelm

Electrical and Computer Engineering Faculty Research & Creative Works

Fundamental EMI source mechanisms leading to common-mode radiation from printed circuit boards with attached cables are presented in this paper. Two primary EMI source mechanisms have been identified: one associated with a differential-mode voltage and another associated with a differential-mode current, both of which result in a common-mode current on an attached cable. These mechanisms can be used to relate printed circuit layout geometries to EMI sources. The two mechanisms are demonstrated through numerical and experimental results, and an example from a production printed-circuit design is presented.

Real-Time Implementation Of An Adaptive Control System For A 3-Zone Rapid Thermal Processing Station, David Hur

Theses

In this thesis, the implementation details of a real time adaptive control system for a TI 3-zone RTP station, as well as the simulation and the experimental results are presented. Extensive simulation of the system is performed in order to ensure proper operation of the system. The experimental results are used to verify proper operation of the closed loop control system. Initial experiments were conducted using two thermocouples. Further experiments were conducted using one thermocouple for the purpose of testing the performance of the system using Extended Kalman Filter as the state estimator.

The implementation of the control system is …

Novel High-Speed Architecture For Machine Vision Applications, Bassam S. Farroha, Raghvendra G. Deshmukh

Electrical Engineering and Computer Science Faculty Publications

This paper focuses on producing a state-of-the-art technique for designing an image recognition system for machine vision applications. The motivation behind the new system design is to provide a unique methodology, using strategic design techniques, to implement a system that addresses real-world image recognition applications. The introduction of application-specific, massively parallel array of processors, where low-level processing is accomplished on reconfigurable hardware structures, highlights the scheme. The system was built and simulated on a VLSI chip and results were verified using Electric Rules Check and Harris Timing Analysis examination tools. The system is composed of there functional layers and a …

Residual Stress Analysis Of Sputtered Tantalum Silicide Thin Film, Young Joo Song

Theses

The influence of different argon pressures on the residual stress, microstructure, and resisitivity of sputtered tantalum silicide thin films has been investigated. TaSi₂ films were deposited onto Si wafers by dc magnetron sputtering. The deposition temperature was assumed to be 300°C. The thickness was about 0.5 μm. The residual stresses in the films deposited at different argon pressures were determined by curvature measurement method. The compressive intrinsic stress of 1033.4MPa was measured at P_Ar = 0.5 mTorr. The intrinsic stress in the films seemed to change from compression to tension as P_Ar increased above 8mTorr. A maximum …

Detecting Stress And Fatigue Cracks, Christian J. Huber, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Discoveries in using open ended rectangular waveguides for microwave surface crack detection and sizing have generated interest. The foundation, potential, advantages and disadvantages of this methodology, developed at the Applied Microwave Nondestructive Testing Laboratory in the Electrical Engineering Department at Colorado State University, are discussed. Microwave techniques in general and this particular approach offer certain unique advantages that can advance the state of the art of fatigue/surface crack detection. The basic features and capabilities of this technique have been theoretically and experimentally investigated these past few years. However, more developmental work is needed to bring this technique from the laboratory …

Real-Time Visual Speech Articulation Training Aid, Neiyer S. Correal

Electrical & Computer Engineering Theses & Dissertations

A real-time visual articulation training aid has been implemented. It provides instantaneous visual feedback of vowel and stop-consonant production on a computer screen. The vowel training system corresponds to an improved floating-point implementation of a previous fixed-point system developed by Beck (1992). The new implementation provides better accuracy and an approximate five-fold increase in speed. Acoustic features computed from global short-time spectral shape are used for classification of vowels. Temporal spectral trajectories timed to begin with burst onset are used for stop consonants. A neural network is used to transform measurements of auditory stimuli from the feature space to a …

Determination Of The Refractive Index And Thickness Of Transparent Pellicles By Use Of The Polarization-Independent Absentee-Layer Condition, Y. Cui, R. M.A. Azzam

Electrical Engineering Faculty Publications

The refractive index and the thickness of a transparent pellicle are determined when the pellicle is placed between two vertical crossed polarizers and rotated in the horizontal plane. The transmission axes of the polarizers are neither parallel nor perpendicular to the plane of incidence. The light transmitted through the crossed polarizers reaches a minimum when the pellicle satisfies the absentee-layer condition. The refractive index and the film thickness are obtained from the pellicle orientation angles under such a condition.

Globally Optimal Periodic Robot Joint Trajectories, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

This paper presents a new method for the planning of robot trajectories. The method presented assumes that joint-space knots have been generated from Cartesian knots by an inverse kinematics algorithm. The method is based on the globally optimal periodic interpolation scheme derived by Schoenberg, and thus is particularly suited for periodic robot motions. Of all possible periodic joint trajectories which pass through a specified set of knots, the trajectory derived in this paper is the ‘best’. The performance criterion used is the integral (over one period) of a combination of the square of the joint velocity and the square of …

Hybrid Kalman / Minimax Filtering In Phase-Locked Loops, Daniel J. Simon, Hossny El-Sherief

Electrical and Computer Engineering Faculty Publications

A method of combining Kahnan filtering and minimax filtering is proposed and demonstrated in an application to phase-locked loop design. Kalman filtering suffers from a lack of robustness to departures from the assumed noise statistics. Minimax filtering, however, has the drawback of ignoring the engineer's (admittedly incomplete) knowledge of the noise statistics. It is shown in this paper that hybrid Kalman/minimax filtering can provide the “best of both worlds” . Phase-locked loop filter design is used in this paper to demonstrate an application of hybrid estimation.

Real-Time Optically Processed Face Recognition System Based On Arbitrary Moiré Contours, Rafael A. Andrade, Bernard R. Gilbert, Donald W. Dawson, Chris L. Hart, Samuel Peter Kozaitis, Joel H. Blatt

Electrical Engineering and Computer Science Faculty Publications

We demonstrate a hybrid electronic-optical real-time system that performs 3-D face recognition. We constructed custom reference gratings that formed a desired moire pattern when mixed with images of structurally illuminated faces. The moiré patterns could be in any form such as, equal depth contours, error maps, or any arbitrary pattern. We demonstrate video methods to generate such error maps in real time, thus developing a real-time automated face recognition system based on the optical processing of arbitrary moiré contours. We chose the moiré pattern to be in the form of a Fresnel zone plate, which is displayed on a liquid …

Real-Time Range Image Segmentation Using Adaptive Kernels And Kalman Filtering, Fred W. Depiero, Mohan M. Trivedi

Electrical Engineering

Segmentation is a fundamental process affecting the overall quality and utility of a machine vision system. Range Profile Tracking (RPT) is a systematic approach for stable, accurate and high speed segmentation of range images that is based on Kalman filtering. Tests of RPT have produced stable decompositions of second order surfaces bounded by jump and crease discontinuities, having a volumetric error of a few percent, in under 6 sec. for a wide variety of conditions. Results from over 900 tests on synthetic scenes and 150 real range images are presented.

Effect Of Unbalance On Power System Components In The Presence Of Harmonics, Jessica Williams

All Theses

No abstract provided.

An Expert System Approach To Emc Modeling, Todd H. Hubing, James L. Drewniak, Thomas Van Doren, Navin Kashyap

Electrical and Computer Engineering Faculty Research & Creative Works

Existing computer software for EMC analysis can be divided into three categories. Analytical modeling codes employ closed form expressions to solve problems of general interest to EMC engineers or circuit designers. Numerical modeling codes use numerical techniques to solve Maxwell's equations subject to specific boundary conditions. EMC rule checkers search a design for features that violate basic EMC design guidelines. This paper outlines the relative advantages and limitations of each of these three approaches and describes an expert system EMC modeling approach. The new approach combines analytical models, numerical models, and EMC rule-checking in order to evaluate designs in much …

Real-Time Optically Processed Face-Recognition System Based On Arbitrary Moire Contours, Rafael A. Andrade, Bernard R. Gilbert, Donald W. Dawson, Chris L. Hart, Samuel Peter Kozaitis, Joel H. Blatt

Electrical Engineering and Computer Science Faculty Publications

A real-time diffraction based optical processed 3-D shape recognition system has been built and demonstrated. The system uses an Ar-ion laser interferometer to project variable spatial frequency structural illumination on 3 dimensional targets which are viewed by a camera. The video data is mixed with a computer generated mask (converted to RS-170 video) and the resulting output video signal is sent to a liquid crystal television (modified to function as a spatial light modulator) which is illuminated by a He-Ne laser. The video mixing process, based on a commercial Chroma-Key circuit, generates an arbitrary moire pattern which is a function …

A Cascadable Pragmatic Block Decoding Algorithm Exploiting Channel Measurement Information, William H. Thesling, Fuqin Xiong

Electrical and Computer Engineering Faculty Publications

The complexity of algorithms to perform soft decision decoding on block codes has impeded their inclusion in practical systems. A well-known class of algorithms for decoding block codes utilizing channel measurement information along with the algebraic properties of the code are the Chase algorithms.¹ In this paper a decoding method similar to Chase's third algorithm is presented. However, in this method, a single test pattern or alternate codeword makes up one stage of the decoder. The method uses information from the previous decoding(s) to assist in generating a test pattern. This single stage ‘Second Chance Algorithm’ can then be …

Scattering Properties Of Dense Media From Monte Carlo Simulations With Application To Active Remote Sensing Of Snow, Lisa M. Zurk, L. Tsang, Dale P. Winebrenner

Electrical and Computer Engineering Faculty Publications and Presentations

Monte Carlo simulations are used to derive the phase matrix, effective permittivity, and scattering coefficient for a random medium consisting of densely packed spheres up to 5000 in number. The results include correlated scattering and coherent wave interaction among the scatterers. The Monte Carlo simulations are based on a multiple-scattering formulation of the Foldy-Lax equations. It is shown that the derived phase matrix is in good agreement with dense media radiative transfer theory for copolarized scattering. The depolarization, however, can be substantially larger than conventional theory. Two methods are used to analyze the behavior of the coherent wave to obtain …

Visual Speech Recognition Using Multiple Deformable Lip Models, Devi Chandramohan

Electrical & Computer Engineering Theses & Dissertations

Motivated by the fact that human speech perception is a bimodal process (auditory and visual), several researchers have designed and implemented automatic speech recognition (ASR) systems consisting of both audio and visual subsystems, and shown improved performance relative to traditional purely auditory systems. Several visual speech reading approaches have used deformable templates to model the shape of a speaker's lips. Deformable templates are models of image objects, which can be deformed by adjusting a set of parameters to match the object in some optimal way, as defined by a cost function. Using a single deformable lip model has disadvantages such …

Two-Dimensional Drift-Diffusion Simulations Of Silicon Avalanche Shaper (Sas) Devices For High Power Applications, Hamid Jalali

Electrical & Computer Engineering Theses & Dissertations

Silicon Avalanche Shaper devices have been projected as being important components of an inexpensive, semiconductor-based technology for high power switching applications. The primary advantage of this technology is that it is based on Silicon material which is easy to fabricate and has a well established processing technology. Unlike other high power technologies, the SAS devices do not rely on external optical triggering which eliminates the need for lasers and related optical circuitry.

The SAS based high power switching technology has been pioneered and tested by a Russian group. Though preliminary results have been very encouraging, the device reliability and its …

Fluid Delivery System By Process Control, Anthony D. Banks

Electronic Dissertations and Theses

The purpose of this design project is to design and demonstrate a complete mechatronic system that will regulate a desired temperature of a fluid and control the rate at which it is delivered. This system can serve several purposes and have numerous applications. In particular, applications are inclusive of, but not limited to the medical administration of certain types of medication. The Fluid Delivery System By Process Control can be utilized to control any number of factors such as the temperature of the medication, rate of administration, flow control, mixture ratios, and time and frequency of administration.

Graph Matching Using A Direct Classification Of Node Attendance, Fred Depiero, Mohan Trivedi, Steve Serbin

Electrical Engineering

An algorithm has been developed that finds isomorphisms between both graphs and subgraphs. The development is introduced in the object recognition problem domain. The method isolates matching subgraphs, finds a node-to-node mapping and reorders nodes, thus permitting a direct comparison to be made between the resultant graphs. The algorithm is of polynomial order. It yields approximate results, maintaining a performance level for subgraph isomorphisms at or above 95% under a wide variety of conditions and with varying levels of noise. The performance on the full size comparisons associated with graph isomorphisms has been found to be 100/100, also under a …

Investigation Of Radio Wave Propagation In The Martian Ionosphere Utilizing Hf Sounding Techniques, Robert J. Yowell

Theses and Dissertations

This thesis presents a preliminary design of an ionospheric sounder to be carried aboard one or more of NASA's Mars Surveyor landers. Past Russian and American probes have indicated the existence of an ionosphere, but none of these missions remotely sensed this atmospheric layer from the surface. The rationale for utilizing a surface-based Martian ionospheric sounder is discussed. Based on NASA's choice of launch vehicle and power source, a low-weight, low-powered Chirp sounder using a horizontally-polarized dipole antenna is recommended for the sounder experiment. The sounder experiment should be conducted for at least one Martian year, in order to investigate …

Characterization And Fabrication Of A (6h)-Sic As A Piezoresistive Pressure Sensor For High Temperature Applications, Robert Sylvester Okojie

Dissertations

A prototype monolithic 6H-SiC pressure sensor operational up to 350°C, with potential to operate up to 600°C, was batch fabricated and tested. At temperatures higher than 450°C, silicon diaphragms creep under minimal load. To operate beyond 450°C, therefore, the use of 6H-SiC was proposed. However, three key technological issues - fabrication, high temperature metallization, and gage factor characterization - had to be resolved. Since conventional fabrication technology is not applicable to SiC due to its near inert chemistry, photoconductive selectivity techniques to etch the piezoresistors were developed. Techniques to wet etch the cavities in a dark current mode were developed, …

Explicit Congestion Control Algorithms For Available Bit Rate Services In Asynchronous Transfer Mode Networks, Ambalavanar Arulambalam

Dissertations

Congestion control of available bit rate (ABR) services in asynchronous transfer mode (ATM) networks has been the recent focus of the ATM Forum. The focus of this dissertation is to study the impact of queueing disciplines on ABR service congestion control, and to develop an explicit rate control algorithm.

Two queueing disciplines, namely, First-In-First-Out (FIFO) and per-VC (virtual connection) queueing, are examined. Performance in terms of fairness, throughput, cell loss rate, buffer size and network utilization are benchmarked via extensive simulations. Implementation complexity analysis and trade-offs associated with each queueing implementation are addressed. Contrary to the common belief, our investigation …

A Full Wave Method For Rough Surface Scattering Using Fictitious Current Distributions, Anthony A. Triolo

Dissertations

Rough surface scattering is a current topic of interest in many diverse fields. But, despite its importance, the two most widely used solution methods, the Kirchhoff and first order perturbation methods, are valid only for a restricted range of surface types. There is a large range of surface statistics for which neither of these theories is valid. There are purely numerical solutions to the problem, i.e., the integral equation technique and FDTD method, but these methods require a prohibitively large amount of computer time and storage space for use in practical applications. A full wave method has been introduced by …

A Digital Signal Processor Based Optical Position Sensor And Its Application To Flexible Beam Control, Thomas J. Spirock

Theses

A Digital Signal Processor (DSP) based optical position sensor was developed. The sensor system consists of the following components: 1) analog electronics, 2) the DSP based synchronous demodulation software, 3) PC based interface software which samples and saves the data, and 4) PC based control codes for a flexible beam. experiment.

The ability of the system to determine the distance from the optical sensor to the power modulated light source was assessed by the following tests: 1) a stationary drift test to evaluate the system's noise, 2) a short-range test to determine the resolution of the optical sensor over a …

The Study Of Sige-Channel Heterojunction Mos Device, Yunchen Qiu

Theses

The advances in the growth of pseudomorphic silicon-germanium epitaxial layer combined with the strong need for high-speed CMOS VLSI circuit have led to increased interest in silicon-based heterojunction MOSFET's transistors. The high-performance heterostructure SiGe MOSFET exhibits higher channel mobility than its bulk Si counterpart. The most critical and challenging process for fabricating a SiGe MOSFET device is that for making a gate oxide with sufficient quality for useful conductivity modulation. PECVD methods was employed to deposit the gate oxide and C-V method was used to investigate the electrical characteristics of the film. For PECVD gate oxide, a film refractive index …

Remote Measurement Calibration In Power System, Xiaofeng Li

Theses

Power system reliability and economy of operation require accurate measurements of current, voltage, real and reactive powers. These measurements are transmitted to a control center of a power system for monitoring, display, and use in power system real-time analysis. The number of measurements is in thousands. Routinely field technicians must calibrate transducers and/or determine other sources of metering errors. Due to the large number of measurements and the time required to check each individual measurement, field calibration procedures are impractical, expensive, and not timely.

There has been a need for a more efficient approach to measurement calibration and identification of …

United States Patent: System And Method For Compensating Polarization-Dependent Sensitivity Of Dispersive Optics In A Rotating Analyzer Ellipsometer System, Steven E. Green, Shakil A. Pittal, Blaine D. Johs, John A. Woollam, David W. Doerr, Reed A. Christenson

Department of Electrical and Computer Engineering: Faculty Publications

An ellipsometer system which includes a pivotal dispersive optics positioned to receive polychromatic light from an analyzer thereof, without further focusing after reflection from a substrate system, is presented. In addition, a rotating compensator, positioned between the analyzer and the dispersive optics, which serves to reduce detector element polarization dependent sensitivity to light entering thereto after it interacts with the dispersive optics, is disclosed. The method of the present invention can include application of mathematical correction factors to, for instance, substrate system characterizing PSI and DELTA values, or Fourier ALPHA and BETA coefficients.

Low-Frequency Noise In 4h-Silicon Carbide Junction Field Effect Transistors, J. W. Palmour, M. E. Levinshtein, S. L. Rumyantsev, Grigory Simin

Faculty Publications

Low frequency noise in 4H‐silicon carbide junction field effect transistors (JFETs) has been investigated. JFETs with a buried p ⁺ n junction gate were manufactured by CREE Research Inc. Very low noise level has been observed in the JFETs. At 300 K the value of Hooge constant α is as small as α∼10⁻⁵ and the α value can be decreased by an appropriate annealing to α∼2×10⁻⁶. It has been shown that even these extremely low noise values are determined not by the volume noise sources but by the noise at the SiC–SiO₂ interface.

Mathematics: Meeting The Needs Of High Education, Industry, And The Students Of Electronics Engineering Technology At Hawkeye Community College, Stanley J. Niedermann

Graduate Research Papers

This study pertained to a problem faced by officials of Hawkeye Community College (HCC). With the Tech-Prep educational reform now taking place in the United States and with the ever increasing diversity of electronics, those officials had to make a decision about the status of the courses entitled Applied Algebra and Electronics Math, both of which are included in the electronics engineering technology program at HCC.

The purpose of this study was to determine which mathematics courses were most appropriate for electronics technicians now and in the near future. Three research questions required answers: Question 1 -- should Applied Algebra …