Engineering Commons^™

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

All Theses

No abstract provided.

Single-Layer Channel Routing And Placement With Single-Sided Nets, Ronald I. Greenberg, Jau-Der Shih

Computer Science: Faculty Publications and Other Works

This paper considers the optimal offset, feasible offset, and optimal placement problems for a more general form of single-layer VLSI channel routing than has usually been considered in the past. Most prior works require that every net has exactly one terminal on each side of the channel. As long as only one side of the channel contains multiple terminals of the same net, we provide linear-time solutions to all three problems. Such results are implausible if the placement of terminals is entirely unrestricted; in fact, the size of the output for the feasible offset problem may be Ω(n^2). The linear-time …

Multiresolution Wavelet Processing For Binary Phase-Only Filters, Samuel Peter Kozaitis

Electrical Engineering and Computer Science Faculty Publications

We used the discrete wavelet transform to approximate an image at a lower resolution in preparation for object recognition using correlation techniques. We cross- correlated the low-resolution image with a similarly processed image containing an object of interest. Then, we synthesized the cross-correlation result to the resolution of original image. Using this approach, we avoided cross- correlating an image multiple times and passing information between levels of an image representation such as an image pyramid. We satisfactorily identified objects at 1/4 resolution using the wavelet representation and binary phase-only filters. We chose wavelets based on their impulse response and found …

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 …

Acuta 25th Annual Conference- Silver Anniversary- July 14-18, 1996- Chicago Hilton & Towers.

ACUTA: Other Publications

Registration & Hotel Information

Registration if postmarked by June 24, 1996.(Extended from June 14)

. Member Institution/Associate Member - $525. Corporate Affiliate - $525. Non-Member - $650

Registration if postmarked after June 24, 1996.

Member Institution/Associate Member - $57. Corporate Affiliate - $575 . Non-Member - $700

Hotel: Chicago Hilton & Towers

312-922-4400. Rates are $118 Single or Double. Be sure and mention the ACUTA rate! Cutoff date

for hotel is June 19,19961

Due to the popularity of this event and the Chicago destination, the hotel is full on some nights.

However, the ACUTA rate of $ll8 single/double per night …

Neural Generalized Predictive Control For Real-Time Control, Donald I. Soloway

Electrical & Computer Engineering Theses & Dissertations

In this thesis a computationally efficient Generalized Predictive Control (GPC) algorithm is presented and implemented. The algorithm is more efficient than others because the number of iterations needed for convergence is significantly lower with Newton-Raphson. The main additional cost with Newton-Raphson algorithm is the calculation of the Hessian. This overhead is not a problem because of the reduced number of iterations, making the algorithm suitable for real-time control. For nonlinear control applications, a neural network is used as a dynamical system predictor leading to a Neural Generalized Predictive Control (NGPC) algorithm which is presented in detail in this thesis. An …

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 …

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 …

Drug Delivery With Microsecond Laser Pulses Into Gelatin, Hanqun Shangguan, Lee W. Casperson, Alan Shearin, Kenton W. Gregory, Scott A. Prahl

Electrical and Computer Engineering Faculty Publications and Presentations

Photo acoustic drug delivery is a technique for localized drug delivery by laser-induced hydrodynamic pressure following cavitation bubble expansion and collapse. Photoacoustic drug delivery was investigated on gelatin-based thrombus models with planar and cylindrical geometries by use of one microsecond laser pulses. Solutions of a hydrophobic dye in mineral oil permitted monitoring of delivered colored oil into clear gelatin-based thrombus models. Cavitation bubble development and photoacoustic drug delivery were visualized with flash photography. This study demonstrated that cavitation is the governing mechanism for photoacoustic drug delivery, and the deepest penetration of colored oil in gels followed the bubble collapse. Spatial …

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 …

Parameter Estimation For Superimposed Weighted Exponentials, Edwards A. Ingham

Theses and Dissertations

The approach of modeling measured signals as superimposed exponentials in white Gaussian noise is popular and effective. However, estimating the parameters of the assumed model is challenging, especially when the data record length is short, the signal strength is low, or the parameters are closely spaced. In this dissertation, we first review the most effective parameter estimation scheme for the superimposed exponential model: maximum likelihood. We then provide a historical review of the linear prediction approach to parameter estimation for the same model. After identifying the improvements made to linear prediction and demonstrating their weaknesses, we introduce a completely tractable …

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 …

A Modularized Software Package For Adaptive Beamforming, Shun-Hsyung Chang, Shao-Wei Leu, Hsing-Wang Liang

Journal of Marine Science and Technology–Taiwan

This paper presents a modularized simulation software package for adaptive beamforming. In recent years, the theory and technology of adaptive beamforming have been applied extensively in many different areas such as radar, sonar, communication systems, and geophysical exploration. As many new beamforming architectures and related algorithms are being introduced, researchers find themselves repeating the laborious process of writing similar software routines in order to conduct simulations. This is largely due to the lack of well-defined and modularized supporting software. Therefore, we have implemented a collection of representative algorithms available for adaptive beamforming and constructed a simulator with menu-driven user interface. …

Network-Integrated Ship Automatic System And Internetworking To The Internet, Li-Der Chou, Jeng Yih Juang

Journal of Marine Science and Technology–Taiwan

Many automatic systems developed for the merchant ships are focused on the Unmanned Machinery Space (UMS), and therefore it is necessary to build a local area network (LAN) on the ship in order to integrate these automatic systems. By means of the Inmarsat satellite system, the shipboard LAN is interconnected with the terrestrial communication networks such as the Internet. In the paper, the shipboard LAN is designed from the view point of survivability, and three concepts to reduce the satellite communication cost for the interconnection of the shipboard LAN and the Internet are proposed. Finally, the way to implement the …

A Study On Fabrication Of Zinc Oxide Thin Film Acoustic Sensors, C.C. Chang, J.H. Chang

Journal of Marine Science and Technology–Taiwan

In this study, acoustic sensors were formed by depositing a zinc oxide (ZnO) thin film on a silicon dioxide/silicon(SiO/Si) substrate using radio frequency (RF) planar-magnetron sputtering method. The results showed higher substrate temperatures and higher RF powers enhanced C-axis oriented structure of the Zno thin film and optimized the ZnO thin film acoustic property. The frequency spectrum measurement on the acoustic sensor underwater involved three peaks at frequencies 640 KHz, 2.4 MHz and 2.9 MHz, respectively. Sensitivity reached to -132.02 dBrelv/ upa. The results indicated that under the pressure of acoustic frequencies the sensor response was directly proportional to pressure …

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.

Extended Permutation Filters And Their Application To Edge Enhancement, Russell C. Hardie, Kenneth E. Barner

Electrical and Computer Engineering Faculty Publications

Extended permutation (EP) filters are defined and analyzed. In particular, we focus on extended permutation rank selection (EPRS) filters. These filters are constrained to output an order statistic from an extended observation vector. This extended vector includes N observation samples and K statistics that are functions of the observation samples. The rank permutations from selected samples in this extended observation vector are used as the basis for selecting an order statistic output. We show that by including the sample mean in the extended observation vector, the filters exhibit excellent edge enhancement properties. We also show that several previously defined classes …

Anion Induced Blue To Purple Transition In Bacteriorhodopsin, Mrunalini Pattarkine, Anil K. Singh

Faculty Works

Purple membrane (PM, λ" role="presentation">λmax" role="presentation">max 570 nm) of H. halobium on treatment with sulphuric acid changes its colour to blue (λ" role="presentation">λmax" role="presentation">max 608 nm). The purple chromophore can be regenerated from the blue chromophore by exogeneous addition of anions such as CI−" role="presentation">− and HPO42−" role="presentation">2−4. Chloride ion is found to be more effective than the dibasic phosphate ion in regenerating the purple chromophore. Nevertheless, one thing common to the anion regeneration is that both CI−" role="presentation">− and HPO42−" role="presentation">2−4 show marked pH effect. At pH 1.0 the efficiency of …

Measurement Parameter Optimization For Surface Crack Detection In Metals Using An Open-Ended Waveguide Probe, R. Zoughi, Stoyan I. Ganchev, Christian J. Huber

Electrical and Computer Engineering Faculty Research & Creative Works

Fatigue and stress induced surface crack detection in metals is an important practical issue. A newly developed microwave inspection approach, using an open-ended rectangular waveguide, has proved to be an effective tool for detecting such cracks. This novel microwave approach overcomes some of the limitations associated with the standard detection methods for surface crack detection. In addition, this approach is applicable to exposed, filled (with a dielectric such as dirt, rust, etc.) and cracks under dielectric coatings such as paint. This paper presents the basic foundation of this surface crack detection methodology along with the ways by which measurement parameters …

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 …

Design, Process And Performance Simulation Of A 360x360-Element Very High Frame Rate Burst-Image Sensor, Guang Yang

Dissertations

A process was developed for fabrication of 360x360-element Very High Frame Rate (VHFR) burst-image sensor on the bases of one-dimensional (1-D) and two-dimensional (2-D) device and process simulations using SUPREM III, SUPREM IV, PISCES IIB and ISE-TCAD software, and the process data provided by the David Sarnoff Research Center. This process includes SiO₂-Si₃N₄ gate dielectric, four-levels of polysilicon, three-levels of metal, eight implants, and requires twenty-one mask levels. The imagers with a 2-cmx2-cm chip size were fabricated at the David Sarnoff Research Center. The VHFR burst-image sensor is capable of capturing images at frame rates …

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 …

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 …

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 …

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 …

Simple Fast Vector Quantization Of The Line Spectral Frequencies, Jin Zhou

Theses

Speech coding has been of interest to communication specialists for years. A number of technologies for describing and transmitting the speech spectral envelope have been studied. Among them, the Vector Quantization (VQ) of Line Spectral Frequencies (LSF) is receiving more attention because of its good rate-distortion performance. Typically, about 30 bits are assigned to code 10-dimensional LSF vectors with a resulting spectral distortion of less than ldB. However, 30-bit full-search VQ is totally impractical in terms of both computational complexity and memory space. Various standard suboptimal, low-complexity VQ techniques have been used for coding the LSF's in the literature. The …

Status Of The Research And Development For Fuel Cell Technology Abroad, Naichao Li, Baolian Yi

Journal of Electrochemistry

Status of the research and development for fuel cell technology abroad was overviewed, and at the aim of accelerating the research and development for fuel cell technology in China, the corresponding stategy for our country was recommended.