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Simulation Study Of Learning Automata Games In Automated Highway Systems, Cem Unsal, Pushkin Kachroo, John S. Bay Nov 1997

Simulation Study Of Learning Automata Games In Automated Highway Systems, Cem Unsal, Pushkin Kachroo, John S. Bay

Electrical & Computer Engineering Faculty Research

One of the most important issues in Automated Highway System (AHS) deployment is intelligent vehicle control. While the technology to safely maneuver vehicles exists, the problem of making intelligent decisions to improve a single vehicle’s travel time and safety while optimizing the overall traffic flow is still a stumbling block. We propose an artificial intelligence technique called stochastic learning automata to design an intelligent vehicle path controller. Using the information obtained by on-board sensors and local communication modules, two automata are capable of learning the best possible (lateral and longitudinal) actions to avoid collisions. This learning method is capable of …


Sliding Mode For User Equilibrium Dynamic Traffic Routing Control, Pushkin Kachroo, Kaan Ozbay Nov 1997

Sliding Mode For User Equilibrium Dynamic Traffic Routing Control, Pushkin Kachroo, Kaan Ozbay

Electrical & Computer Engineering Faculty Research

Presents a solution to the user equilibrium dynamic traffic routing (DTR) problem for a point diversion case using feedback control methodology. The sliding mode control technique which is a robust control methodology applicable to nonlinear systems in canonical form is employed to solve the user equilibrium DTR problem. The canonical form for this problem is obtained by using a feedback linearization technique, and the uncertainties of the system are countered by using the sliding mode principle. Simulation results show promising results.


An Experimental Procedure For Characterizing Interconnects To The Dc Power Bus On A Multilayer Printed Circuit Board, Hao Shi, James L. Drewniak, Todd H. Hubing, Thomas Van Doren, Fei Sha Nov 1997

An Experimental Procedure For Characterizing Interconnects To The Dc Power Bus On A Multilayer Printed Circuit Board, Hao Shi, James L. Drewniak, Todd H. Hubing, Thomas Van Doren, Fei Sha

Electrical and Computer Engineering Faculty Research & Creative Works

The effectiveness of dc power-bus decoupling is impacted by the inductance associated with interconnect vias in printed circuit boards (PCB's). Adequate characterization of these interconnects is necessary to facilitate modeling and simulation, and to assess the effectiveness of added decoupling. In this study, a measurement procedure is presented for determining the series inductance and resistance of an interconnect with a network analyzer. The validity and limitations of the procedure are discussed. Experimental results of interconnect parameters on an 8 × 10 in ten-layer test-board corroborate those measured with a precision impedance analyzer. The measured interconnect values are used to simulate …


Modeling Of Surface Hairline-Crack Detection In Metals Under Coatings Using An Open-Ended Rectangular Waveguide, Christian J. Huber, Habibollah Abiri, Stoyan I. Ganchev, R. Zoughi Nov 1997

Modeling Of Surface Hairline-Crack Detection In Metals Under Coatings Using An Open-Ended Rectangular Waveguide, Christian J. Huber, Habibollah Abiri, Stoyan I. Ganchev, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

A surface-breaking hairline crack or a narrow slot in a metallic specimen when scanned by an open-ended rectangular waveguide probe influences the reflection-coefficient properties of the incident dominant mode. Subsequent recording of a change in the standing-wave pattern while scanning such a surface results in what is known as the crack characteristic signal. Since microwave signals penetrate inside dielectric materials, this methodology is capable of detecting cracks under dielectric coatings of various electrical thicknesses as well. To electromagnetically model the interaction of an open-ended rectangular waveguide with a surface-breaking hairline crack under a dielectric coating, the dielectric-coating layer is modeled …


Quantifying Emi Resulting From Finite-Impedance Reference Planes, David M. Hockanson, James L. Drewniak, Todd H. Hubing, Thomas Van Doren, Fei Sha, Cheung-Wei Lam, Lawrence Rubin Nov 1997

Quantifying Emi Resulting From Finite-Impedance Reference Planes, David M. Hockanson, James L. Drewniak, Todd H. Hubing, Thomas Van Doren, Fei Sha, Cheung-Wei Lam, Lawrence Rubin

Electrical and Computer Engineering Faculty Research & Creative Works

Parasitic inductance in printed circuit board (PCB) geometries can detrimentally impact the electromagnetic interference(EMI) performance and signal integrity of high-speed digital designs. This paper identifies and quantifies the parameters that affect the inductance of some typical PCB geometries. Closed-form expressions are provided for estimating the inductances of simple trace and ground plane configurations.


Microstrip Zero-Sum Antenna; Cad And Experimental Study, Tuan H. Lam Oct 1997

Microstrip Zero-Sum Antenna; Cad And Experimental Study, Tuan H. Lam

Theses

A microstrip antenna array consisting of two elements combined with a stripline hybrid (rat-race) ring coupler is used to implement a zero-sum antenna. Numerical optimization of individual antenna elements in terms of feed location and patch size was achieved using IE3D (Zeland Software Inc., Fremont, CA), a fullwave 3-D planar electromagnetic simulation software. Further, design of a hybrid (rat-race) ring coupler in a stripline environment was carried out, yielding the sum and difference functions as 0.5 dB and 40 dB, respectively. A combination of a two-element antenna array and a hybrid (rat-race) ring coupler as a zero sum antenna has …


Motion-Compensating Long-Term Memory Prediction, Thomas Wiegand, Xiaozheng Zhang, Bernd Girod Oct 1997

Motion-Compensating Long-Term Memory Prediction, Thomas Wiegand, Xiaozheng Zhang, Bernd Girod

Electrical Engineering

Motion-compensating long-term memory prediction extends the spatial displacement utilized in block-based hybrid video coding by a variable time delay permitting the use of more frames than the previously decoded one for motion compensation. The long-term memory covers the decoded frames of some seconds at encoder and decoder. We investigate the influence of memory size in our motion compensation scheme and analyze the trade-off between the bit-rates spent for motion compensated prediction and residual coding. Simulation results are obtained by integrating long-term memory prediction into an H.263 codec. PSNR improvements up to 2 dB for the Foreman sequence and 1.5 dB …


Development Of The Base Station Transceiver Subsystem In The Cdma Mobile System, Dong-Wook Lee, Kisuk Yoo, Jin-Su Kim, Myoung Jin Kim, Jae-Hong Park Oct 1997

Development Of The Base Station Transceiver Subsystem In The Cdma Mobile System, Dong-Wook Lee, Kisuk Yoo, Jin-Su Kim, Myoung Jin Kim, Jae-Hong Park

Electrical Engineering and Computer Science Faculty Publications

The base station transceiver subsystem (BTS) of the CDMA Mobile System is interfaced to mobile stations over the air and to the wired network through a packet switched interconnection network. The potential benefits of CDMA technology are achieved when the transmitter and the receiver are properly designed and implemented. The physical layer of the air interface at the base station is implemented with the CDMA ASICs and control circuits in the channel card of the BTS. We present the design perspectives and structural illustration of the BTS. Base station modem ASICs and their control to implement the CDMA receiver, baseband …


Frequency-Mixing Detection Of Polarization-Modulated Light Using Different Periodic Analyzers, R.M.A. Azzam Oct 1997

Frequency-Mixing Detection Of Polarization-Modulated Light Using Different Periodic Analyzers, R.M.A. Azzam

Department of Electrical and Computer Engineering: Faculty Publications

We derive the equations that permit the use of six different periodic analyzers for the frequency- mixing detection (FMD) of polarization -modulated light. The six periodic analyzers are (1) the rotating linear analyzer, (2) rotating half -wave plate and fixed linear analyzer, (3) rotating quarter -wave plate and fixed linear analyzer, (4) rotating linear analyzer and fixed linear analyzer, (5) oscillating -phase retarder and fixed linear analyzer, and (6) oscillating optical rotator and fixed linear analyzer. In all cases, the average polarization and the polarization and intensity modulation parameters of the light beam can be determined easily and explicitly from …


Block-Based Hybrid Video Coding Using Motion-Compensated Long-Term Memory Prediction, Thomas Wiegand, Xiaozheng Zhang, Bernd Girod Sep 1997

Block-Based Hybrid Video Coding Using Motion-Compensated Long-Term Memory Prediction, Thomas Wiegand, Xiaozheng Zhang, Bernd Girod

Electrical Engineering

Our new approach extends the spatial displacement vector utilized in block-based hybrid video coding by a variable time delay permitting the use of more frames than the previously decoded one for motion compensation. The longterm memory covers the decoded frames of some seconds at the encoder's as well as the decoder's side. This scheme is well suited in cases of repetition in the sequence, e.g. a head is rotating back into its old position, or if the camera is shaking. However, transmission of the variable time delay requires additional bit-rate which may be prohibitive when the size of the long-term …


Color Image Filters: The Vector Directional Approach, Konstantinos N. Kostas Plataniotis, Dimitrios Androutsos Sep 1997

Color Image Filters: The Vector Directional Approach, Konstantinos N. Kostas Plataniotis, Dimitrios Androutsos

Electrical Engineering and Computer Science Faculty Publications

Processing of color image data using directional information has received increased attention lately due to the introduction of the vector directional filters. These rank-ordered type filters utilize the direction of color vectors to enhance, restore and segment color images. First, the different vector directional filters already in use are presented, focusing on their similarities and differences and, second, new adaptive vector directional filters are introduced. Fuzzy as well as nearest neighbor structures are utilized to determine the weights in the proposed adaptive filters. Simulation studies involving color images are used to assess the performance of the different vector directional filters …


Modeling Intelligent Control Of Distributed Cooperative Inferencing, Edward M. Williams Sep 1997

Modeling Intelligent Control Of Distributed Cooperative Inferencing, Edward M. Williams

Theses and Dissertations

The ability to harness different problem-solving methods together into a cooperative system has the potential for significantly improving the performance of systems for solving NP-hard problems. The need exists for an intelligent controller that is able to effectively combine radically different problem-solving techniques with anytime and anywhere properties into a distributed cooperative environment. This controller requires models of the component algorithms in conjunction with feedback from those algorithms during run-time to manage a dynamic combination of tasks effectively. This research develops a domain-independent method for creating these models as well as a model for the controller itself. These models provide …


Azimuthal Modulation Of C-Band Scatterometer Over Southern Ocean Sea Ice, David G. Long, David S. Early Sep 1997

Azimuthal Modulation Of C-Band Scatterometer Over Southern Ocean Sea Ice, David G. Long, David S. Early

Faculty Publications

In a continuing evaluation of the ERS-1 C-band scatterometer as a tool for studying polar sea ice, the authors evaluate the azimuthal modulation characteristics of Antarctic sea ice. ERS-1 AMI scatterometer mode data sets from several study regions dispersed in the Antarctic seasonal sea ice pack are evaluated for azimuthal modulation. When appropriate, the incidence angle dependence is estimated and removed in a study region before determining whether azimuthal modulation is present in the data. Other comparisons are made using the fore and aft beam measurement difference. The results show that over the ice pack, azimuthal modulation is less than …


Investigation Of Internal Partitioning In Metallic Enclosures For Emi Control, S. Radu, Min Li, Joe Nuebel, David M. Hockanson, Yun Ji, James L. Drewniak, Todd H. Hubing, Thomas Van Doren Aug 1997

Investigation Of Internal Partitioning In Metallic Enclosures For Emi Control, S. Radu, Min Li, Joe Nuebel, David M. Hockanson, Yun Ji, James L. Drewniak, Todd H. Hubing, Thomas Van Doren

Electrical and Computer Engineering Faculty Research & Creative Works

High clock frequencies and short-edge rates in present high-speed digital systems result in EMI problems at increasingly higher frequencies. At these speeds, clock harmonics have sufficient energy in the range above 500 MHz to excite cavity modes of a conducting enclosure, and to drive even small length slots and apertures that are unavoidable in a practical design, and can result in an EMI problem. One approach to mitigate these problems is to partition the enclosure into several smaller internal shielded compartments. To study the factors which affect this partitioning, a special enclosure that can be divided into two internal compartments …


A Unified Green's Function Analysis Of Complicated Dfb Lasers, Jim D. Freeze, Michael A. Jensen, Richard H. Selfridge Aug 1997

A Unified Green's Function Analysis Of Complicated Dfb Lasers, Jim D. Freeze, Michael A. Jensen, Richard H. Selfridge

Faculty Publications

An efficient full-wave analysis technique for one-dimensional optical domains, known as the recursive Green's function method (RGFM), is presented for evaluation of distributed feedback (DFB) laser cavities with arbitrary material profiles. The method first constructs the Green's function of an inhomogeneous domain and subsequently uses Green's theorem to determine the laser optical field, lasing wavelength, and threshold gain. The technique is applied to investigate the performance of three DFB laser structures: a chirped-grating configuration, a modulated stripe width design, and a reduced duty cycle complex-coupled device. These structures are evaluated in terms of their single-mode lasing behavior and the uniformity …


High-Performance Input/Output Circuit For Cmos Integrated Circuit Interface, Chee How Lim Jul 1997

High-Performance Input/Output Circuit For Cmos Integrated Circuit Interface, Chee How Lim

Dissertations and Theses

In recent years, strong demand for high-performance electronic products has fueled the need for high-speed and high-integration VLSI circuits. This demand is expected to continue growing in the future, which will lead to development of IC's that are much more compact and operate at higher frequencies. As a result, preserving signal integrity for proper IC communications becomes an increasingly difficult challenge.

In this thesis, an understanding of IC noise in relation to IC packaging is sought. An IC package is modeled with sophisticated 3-D simulators to extract its corresponding parasitics. These parasitics, expressed in terms of resistance, inductance, and capacitance …


A Piezoresistive Metal Thin Film Tilt Sensor, Todd Allan Lindley Jul 1997

A Piezoresistive Metal Thin Film Tilt Sensor, Todd Allan Lindley

Electrical & Computer Engineering Theses & Dissertations

Thin film strain gauges have many applications as transducers for monitoring pressure, vibration, and acceleration. In this thesis, a simple system, consisting of a Nichrome thin film strain gauge deposited on a glass substrate, is investigated in detail. Finite element analysis is used to model the expected sensor behavior. The substrate is shaped to exhibit a constant strain distribution, and is set up in a cantilever beam configuration. R. F. sputtering is used to deposit the Nichrome film, and the resistor pattern is transferred via photolithography. The gravitational force on a mass attached to the free end of the sensor …


Electromyography (Emg) Signal Classification By Artificial Neural Networks, Behnam Dashtipour Jul 1997

Electromyography (Emg) Signal Classification By Artificial Neural Networks, Behnam Dashtipour

Electrical & Computer Engineering Theses & Dissertations

EMG signal processing is one of the active fields of biomedical signal processing. One unanswered question is how to determine whether a muscle is fatigued by analyzing the EMG signal. Fatigue detection could be useful in several different practical situations. There are several studies which show there are differences between EMG signal features before fatigue and after fatigue. Generally studies are based on an analytical analysis of the EMG signal instead of a quantitative analysis. In all previous studies in EMG signal processing for fatigue/nonfatigue detection, the result is that there exist some differences between the EMG signal before muscle …


Achieving Cochannel Interference Objectives Over Selected Topologies In The Portland Oregon Cellular Network, David A. Wand Jun 1997

Achieving Cochannel Interference Objectives Over Selected Topologies In The Portland Oregon Cellular Network, David A. Wand

Dissertations and Theses

Wireless cellular mobile communications is a rapidly growing global technology which places increasing demands on a limited electromagnetic radio frequency spectrum. However, in North America only a 25 MHz block of spectrum has been allocated to each of two service providers. This must be utilized for all services offered within their assigned market.

The wireless cellular link from the mobile or portable phone to terrestrial base stations utilize this limited frequency spectrum. This is divided into 416 two-way channels, each 30 kHz in width, a subset of which is assigned to each base station. As more base stations are constructed, …


Diffraction Analysis And Tactical Applications Of Signal Propagation Over Rough Terrain, You-Cheol Jang Jun 1997

Diffraction Analysis And Tactical Applications Of Signal Propagation Over Rough Terrain, You-Cheol Jang

Theses and Dissertations

The free space propagation model is inadequate to predict the mean path-loss in ground wireless communication. Also, many existing propagation channel models do not adequately predict path-loss in rough terrain because most of them were based on measurements in urban areas. Hence, a channel model that estimates mean path-loss over many different kinds of terrain conditions is desired. In this thesis, two new propagation channel models, Real Terrain Diffraction Model (RTDMOD) and Universal Terrain Channel Model (UTCMOD), were developed. Other geometric theory of diffraction (GTD) methods (Epstein-Peterson (EP) and Deygout (DG)) agree within 5 % from 3 MHz to 3GHz …


Robust Control Of Smart Structures Using Neural Network Hardware, Rajendra Damle, Vittal Rao, Frank J. Kern Jun 1997

Robust Control Of Smart Structures Using Neural Network Hardware, Rajendra Damle, Vittal Rao, Frank J. Kern

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the use of Intel's Electronically Trainable Analog Neural Network (ETANN) chipi80170NX for implementing single-chip robust controllers for smart structures is successfully demonstrated. Robust controllers like the linear quadratic regulator (LQR) and linear quadratic Gaussian with loop transfer recovery (LQG/LTR) are implemented in various configurations using the ETANN chip on the smart structure test article. The test article is a cantilevered plate with PZTs as actuators and shaded PVDF film as sensors. The spatially distributed sensors allow direct measurement of the states of the system enabling the implementation of the LQR controller. A two step connectionist approach is …


Design Fabrication And Characterization Of High Performance In Gaas/Inp Focal Plane Array In The 1-2.6 Μm Wavelength Region, Krishna R. Linga May 1997

Design Fabrication And Characterization Of High Performance In Gaas/Inp Focal Plane Array In The 1-2.6 Μm Wavelength Region, Krishna R. Linga

Dissertations

This research thesis describes a new InxGa1-xAs/InAysP1-y/InP technology for long wavelength photodetectors and photodetector arrays. A unique and novel detector structure was designed and fabricated using Hydride Vapor Phase Epitaxy, for low leakage current photodetector arrays in the 1-2.6 µm wavelength region. Potential applications of InGaAs focal plane arrays include near-infrared spectroscopy, fluorescence, remote sensing, environmental sensing, space and astronomical applications. The unique design concepts included the step grading of InAsP layers, lower lattice mismatch between the two InAsP graded layers, lattice matched InAsP cap layer and InGaAs absorption layer, sulphur doping …


Adaptive Space-Time Processing For Digital Mobile Radio Communication Systems, Amit Shah May 1997

Adaptive Space-Time Processing For Digital Mobile Radio Communication Systems, Amit Shah

Dissertations

The performance of digital mobile radio communication systems is primarily limited by cochannel interference and multipath fading. Antenna arrays, with optimum combining (OC), have been shown to combat multipath fading of the desired signal and are capable of reducing the power of interfering signals at the receiver through spatial filtering. With OC, the signals received by several antenna elements are weighted and combined to maximize the output signal-to-interference-plus-noise ratio (SLNR). We derive new closed-form expressions for (1) the probability density function (PDF) of the SINR at the output of the optimum combiner, (2) the average probability of bit error rate …


Motion Compensation And Very Low Bit Rate Video Coding, Shu Lin May 1997

Motion Compensation And Very Low Bit Rate Video Coding, Shu Lin

Dissertations

Recently, many activities of the International Telecommunication Union (ITU) and the International Standard Organization (ISO) are leading to define new standards for very low bit-rate video coding, such as H.263 and MPEG-4 after successful applications of the international standards H.261 and MPEG-1/2 for video coding above 64kbps. However, at very low bit-rate the classic block matching based DCT video coding scheme suffers seriously from blocking artifacts which degrade the quality of reconstructed video frames considerably. To solve this problem, a new technique in which motion compensation is based on dense motion field is presented in this dissertation.

Four efficient new …


Analysis Of 320x240 Uncooled Microbolometer Focal Plane Array And Design Of Thermoelectric Cooler Controller, Takayoshi Fukaya May 1997

Analysis Of 320x240 Uncooled Microbolometer Focal Plane Array And Design Of Thermoelectric Cooler Controller, Takayoshi Fukaya

Theses

Uncooled microbolometer focal plane array is one of the promising method used in uncooled infrared imaging projects. The array's advantages over the conventional cooled imagers are its ability to operate without cryogenic cooler or dewar and its low cost. For the past several years, the ULTRA (Uncooled, Low cost, Technology Reinvestment Alliance) Consortium has been developing uncooled microbolometer imaging system.

This thesis investigates the technology behind the ULTRA camera system. The theoretical as well as the operation of the uncooled microbolometer focal plane array and the processing hardware and software is analyzed and explained.

Thermoelectric cooler controller for the microbolometer …


Petri Net Modeling And Performance Analysis Of Z39.50 Search And Retrieval Protocol, Roopali Paranjpe May 1997

Petri Net Modeling And Performance Analysis Of Z39.50 Search And Retrieval Protocol, Roopali Paranjpe

Theses

Z39.50 is an American Standard for information retrieval. The standard depicts a client-server model of computing. With reference to the Open System Interconnection (COSI)) model developed by International Standards Organization (ISO); Z39.50 is an application layer protocol. A Z39.50 client performs searching, querying and requesting functions and a Z39.50 server interfaces with the database in the remote system and responds to client requests by providing a set of records for the search query.

Z39.50 state tables describe a complex set of concurrent and serial events. A Petri net model is prepared for the entire system comprising the protocol. A Petri …


Low Frequency Characterization Of A Loop Antenna, Irene Koukhta May 1997

Low Frequency Characterization Of A Loop Antenna, Irene Koukhta

Theses

The conventional solution of an integral equation for the loop antenna in free space can be expressed analytically using Fourier Series. However, the solutions based on delta gap feed model yield divergent input susceptance.

To overcome such diverging results, alternative solution using equivalent magnetic frill current feed models were implemented. Although low frequency models for delta gap feeds were suggested, no generalized low frequency expansions for the input admittance have been reported previously. In this work, such generalized low frequency expansion are developed for both delta-gap and magnetic frill feeds of loop antennas. Validity of such expansion have been investigated …


Cr9000 Measurement And Control System Pcmcia-Ata Software Device Interface, Ryan Jon Soulier May 1997

Cr9000 Measurement And Control System Pcmcia-Ata Software Device Interface, Ryan Jon Soulier

Undergraduate Honors Capstone Projects

Many industries have a need for high speed data collection of a large amount of data. For example, the auto industry extensively tests vehicles for resistance to stress, temperature, and moisture. Campbell Scientific, Inc. (CSI) has built the CR9000 measurement and control system that fills this need by being able to measure up to 252 separate sensors at a sustained rate of up to ten thousand samples per second.

The CR9000 system lacks efficiency because it has only a small, fixed amount of memory and is capable of recording data only for a short period. Older devices designed by CSI …


Comparison Of Fdtd Algorithms For Subcellular Modeling Of Slots In Shielding Enclosures, Kuang-Ping Ma, Min Li, James L. Drewniak, Todd H. Hubing, Thomas Van Doren May 1997

Comparison Of Fdtd Algorithms For Subcellular Modeling Of Slots In Shielding Enclosures, Kuang-Ping Ma, Min Li, James L. Drewniak, Todd H. Hubing, Thomas Van Doren

Electrical and Computer Engineering Faculty Research & Creative Works

Subcellular modeling of thin slots in the finite-difference time-domain (FDTD) method is investigated. Two subcellular algorithms for modeling thin slots with the FDTD method are compared for application to shielding end osures in electromagnetic compatibility (EMC). The stability of the algorithms is investigated, and comparisons between the two methods for slots in planes, and slots in loaded cavities are made. Results for scattering from a finite-length slot in an infinite plane employing one of the algorithms are shown to agree well with published experimental results, and power delivered to an enclosure with a slot agree well with results measured for …


Telemetric Torque Measurement System, Jason Joseph, Francisco Sinta, Jeff Williams Apr 1997

Telemetric Torque Measurement System, Jason Joseph, Francisco Sinta, Jeff Williams

Honors Theses

The Telemetric Torque Measurement System(TTMS) was designed to measure the torque produced by a snowmobile engine. The design of the TTMS was refined and modified in stages, leading to the final design. The TTMS consists of two basic sections: the transmitter section and the frequency demodulator section. The transmitter section effectively measures the torque on a snowmobilejack-shaft. The torque signal is converted into a voltage which is then fed into a voltage to frequency converter and converted into an audio tone. This tone is broadcast in the FM broadcast band via an FM transmitter. An FM receiver then receives the …