Engineering Commons^™

Multi-Wavelength Pyrometric Systems For Emissivity-Independent Non-Contact Temperature Sensing, Michael B. Kaplinsky

Dissertations

A Multi-Wavelength Imaging Pyrometer (M-WIP) for real-time remote sensing of temperature profiles of targets with unknown emissivity was developed and demonstrated. To measure the spectral radiance of a target at several distinct wavelengths an M-WIP system was implemented based on an 320x122-element PtSi IR-CCD imager with an assembly of 7 narrow-band 1k filters in the range from 1790nm to 4536nm. A real-time algorithm for simultaneous estimation of the temperature and model parameters of the target emissivity from the least-squares fit of the theoretical model of 1k camera output signal to the experimental spectral measurements was developed and implemented. This rea1-time …

Development Of A Mathematical Model Of Gait Dynamics, Tae Ho Choi

Dissertations

There exists hypothesis that gait selection is strongly correlated with mechanical energy efficiency in normal subjects. The hypothesis is experimentally proven, and intuitively taken for granted. However, it is not mathematically proven that the minimum energy consumption hypothesis is the underlying principle for the normal human gait. To prove the hypothesis we have developed a mathematical model of human walking, in which it is possible to predict an optimal gait at any given speed of walking based on the principle of minimum mechanical energy consumption.

This improved model, which includes the double-support phase of walking as well as the swing …

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 …

Performance Optimization Of Very High Frame Rate Ccd Burst-Image Sensors, Zeynep M. Pektas

Dissertations

The primary objective of this work was to demonstrate the feasibility of an image sensor that is capable of capturing images at 10⁷ frames per second. Such high frame rate operation is based on storage of a certain (N) number of frames into the BCCD memory registers and readout at a slower rate at the end of the frame collection period. To accommodate an optical frame time of 100ns, a high-speed virtual-gate photodetector with six multiple n-type implants was proposed and a novel design strategy was developed. The feasibility of this design was demonstrated by simulating the entire photodetector …

Hydrocatalysis: A New Energy Paradigm For The 21st Century, Peter Mark Jansson

Theses and Dissertations

This thesis will review the problems of worldwide energy supply, describe the current technologies that meet the energy needs of our industrial societies, summarize the environmental impacts of those fuels and technologies and their increased use by a growing global and increasingly technical economy. This work will also describe and advance the technology being developed by BlackLight Power, Inc. [BLP], a scientific company located in Malvern, Pennsylvania. BLP's technology purports to offer commercially viable and useful heat generation via a previously unrecognized natural phenomenon - the catalytic reduction of the hydrogen atom to a lower energy state. A review of …

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 …

Analysis And Comparison Of Resistive, Ferroelectric And Pyroelectric Uncooled Bolometers For Electronic Imaging Systems, Mo-Huang Li

Theses

The performance parameters (responsivity (R_v). detectivity (D*), total noise and response time) of resistive, pyroelectric and ferroelectric bolometer detectors are dependent on a large number of key variables including chopping frequercy, the input impedance and voltage noise of the readout circuitry, the structure dependent parameters (particularly thermal conductance and thermal capacitance), and material properties such as dielectric constant, pyroelectric coefficient, loss tangent and thin film thickness. The interrelationship between the key variables and their influence on performance is often complex and not easily discerned for the three major types of thermal detectors: resistive, pyroelectric and ferroelectric bolometers.

In …

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

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 …

Studies Of Electrocatalytic Properties Of Electrode Of Dispersed Pt On Gc Support In Ethylene Glycol Oxidation, Shengpei Chen, Shigang Sun, Zhiyou Zhou, Shuanjing Hong

Journal of Electrochemistry

The structures and properties of electrocatalyst of dispersed Plutinum (Pt) on glassy carbon (GC) support under different conditions were studied using cyclic voltammetry, potential step technique, X-ray diffraction (XRD) and scanning Electron microscopy (SEM). The results indicated that after having been treated in high temperature,the dispersed Pt on GC support was recrystallised with preferented orientation, and the grain of Pt microcrystal become large and regular. It was illustrated that the dispersed Pt on GC support after high temperature treatment exhibited better stability and high activity for ethylene glycol oxidation.

Polymer Electrolyte Fuel Cell Powered Vehicles, Naichao Li, Baolian Yi

Journal of Electrochemistry

The background, status and commercialization prospect of polymer electrolyte fuel cell vehicles are surveyed in this paper. The technology of this cell and system used in vehicles is discussed.

Electrochemical Behavior Of Superoxide Dismutase On Gold Minigrid With Thin Layer Cell, Xiaqin Wu, Qian Liu, Bin Xu, Xiaoyun Men, Zongrang Zhang

Journal of Electrochemistry

The electrochemical behavior of superoxide dismutase (Cu, Zn-SOD) was investigated on gold wire electrode and gold minigrid with thin layer cell by cyclic voltammetry. A quasi reversible redox wave of SOD has obtained on gold minigrid thin layer electrode, but only oxidation peak has observed on gold wire electrode. The electrochemical reaction parameters, such as the formal potential E^0′, diffusion coefficient D and standard rate constant k^0′ were estimated.

Surface Modification Of Molten Carbonate Fuel Cell Anode, Baizeng Fang, Xinyu Liu, Xindong Wang, Shuzhen Duan

Journal of Electrochemistry

In this study, the anode material of molten carbonate fuel cell was modified by the deposition of niobium on nickel surface. The results of polarization experiments reveal that the corrosion resistant properties as well as electrocatalytic activity have been improved greatly.

Electroluminescence Of Photoelectrochemically Etched N+-Si, Guozheng Li, Chengqian Zhang, Xiumei Yang

Journal of Electrochemistry

Porous silicon with micrometer size pores, which is made on n⁺-Si by photoelectrochemically etched, has electroluminescent property. Each monochromic intensity and wavelength range of luminescent spectra depend on polarized potential. The intersity and the stability of cathodic electroluminescence is high than those of anodic one. Voltammetric behavior before quenching indicated that the electrochemical reactions of some surface species are involved in except the reduction of S₂O₈^2-, which leads to radiative recombination. The energy band diagram based on n⁺-Si(E_g=1.1 eV)/PS(E_g=1.8 eV) junction is proposed.

Modeling And Simulation Of Manufacturing Systems Under Signal Kanban Policies, Lawrence E. Holloway

Electrical and Computer Engineering Presentations

A signal kanban system is used to order the production of various parts by processes with lengthy setup times, such as in metal stamping or injection molding. In this paper, we explore the behavior of signal kanban systems using simulations of systems producing two part types. Such simple models allows a visualization of the changes in the inventories of these parts under the signal kanban system. We consider the operation of the common fixed-batch signal kanban system, and a variation that we refer to as a fixed-fill policy. These policies are investigated under variations in demand, occasional disruptions in production, …

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 …

Mechanism Of Anomalous Photoinduced Transient Current Peak In Amorphous Silicon Thin-Film Transistor, M. H. Chu, Cheng-Hsiao Wu

Electrical and Computer Engineering Faculty Research & Creative Works

The photoinduced transient current from an amorphous silicon thin-film transistor is computed and the mechanism described in terms of trap-state filling dynamics. The direction of the current flow and the location of the transient peak depends strongly on the distributions of donorlike and acceptorlike trap states in the neighborhood of the dark Fermi level. We show that the transient current can flow in the same direction as in the crystalline transistor, as well as in the opposite direction. There is also an interesting cross-over behavior in which the transient current flows out of the drain terminal as a pulse of …

Training Strategies For Critic And Action Neural Networks In Dual Heuristic Programming Method, Christian Peter Paintz

Dissertations and Theses

This thesis discusses strategies for and details of training procedures for the Dual Heuristic Programming (DHP) methodology. This and other approximate dynamic programming approaches (HDP, DHP, GDHP) have been discussed in some detail in the literature, all being members of the Adaptive Critic Design (ACD) family. The example applications used here are the inverted pendulum problem and a fully nonlinear constant velocity bicycle steering model. The inverted pendulum has been successfully controlled using DHP, as reported in the literature. This thesis suggests and investigates several alternative D HP training procedures and compares their performance with respect to convergence speed and …

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 …

Surface Micromachined Pressure Sensors, William P. Eaton Iv

Electrical and Computer Engineering ETDs

Surface micromachined pressure sensors were designed, modeled, fabricated, and tested. They employed a piezoresistive transduction mechanism and were based upon circular diaphragms, which vary from 50 to 1000 μm in diameter and 1 to 2 μm in thickness. The piezoresistors were placed in Wheatstone bridge configurations to provide simple signal amplification and first order temperature compensation.

Of the different micromachining techniques, surface-micromachining has the advantage of being the most similar to integrated circuit manufacturing. Hence an existing IC equipment set can be used to create mechanical structures. Furthermore, the monolithic integration of a mechanical device with control electronics is simpler …

Secondary Dark Rings Of Internal Conical Refraction, Karl F. Warnick, David V. Arnold

Faculty Publications

This paper treats the phenomenon of internal conical refraction, in which a narrow beam propagating along an optical axis of a biaxial anisotropic medium spreads into a hollow cone. An expression is obtained for the intensity distribution produced by conical refraction that predicts additional fringes concentric to the well known Poggendorf dark ring for certain propagation distances and beam widths.

Gate Transient Equations For Digital Bicmos Circuits, Beshara Elmufdi

Honors Capstones

No abstract provided.

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 …

In-Situ Ellipsometric Control Of Magnetic Multilayer Deposition (Abstract), Xiang Gao, Scott Heckens, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

Correct determination of layer thicknesses on a subnanometer scale is crucial for studies of giant magnetoresistance, magneto-optical (MO) Kerr rotation, magnetic interlayer coupling, and other magnetic properties of metallic multilayers. Some structures such as [Co/Ni] and [Co/Pt] with fewer than 20 repeats are difficult to be analyzed by x-ray diffraction (XRD) due to too little material. In this work, in-situ spectroscopic ellipsometry (in-situ SE) is used to precisely determine the optical constants undisturbed by oxidation, and the growth rates of different metal films deposited in a sputtering chamber. In-situ SE determines both the constant and continuously changing growth rates …

Comparison Of Three Clustering Algorithms And An Application To Color Image Compression, Jihun Cha, Laurene V. Fausett

Electrical Engineering and Computer Science Faculty Publications

This paper investigates a traditional clustering algorithm (K-means) and two neural networks (SOM and ART-F). The characteristics of each algorithm are illustrated by simulating geometric space data clustering. Then each algorithm is applied to image data sets to compress the size by reducing the number of colors from 256 to 16.

Comparison Of Neural Network Applications For Channel Assignment In Cellular Tdma Networks And Dynamically Sectored Pcs Networks, William S. Hortos

Electrical Engineering and Computer Science Faculty Publications

The use of artificial neural networks (NNs) to address the channel assignment problem (CAP) for cellular time-division multiple access and code-division multiple access networks has previously been investigated by this author and many others. The investigations to date have been based on a hexagonal cell structure established by omnidirectional antennas at the base stations. No account was taken of the use of spatial isolation enabled by directional antennas to reduce interference between mobiles. Any reduction in interference translates into increased capacity and consequently alters the performance of the NNs. Previous studies have sought to improve the performance of Hopfield- Tank …

Robust Partial Least-Squares Regression: A Modular Neural Network Approach, Thomas M. Mcdowall, Fredric M. Ham

Electrical Engineering and Computer Science Faculty Publications

We have developed a robust Partial Least-Squares Regression (PLSR) neural network approach to statistical calibration model development. Generalized neural network learning rules derived from a weighted statistical representation error criterion that grows less than quadratically are presented. This optimization criterion allows for higher-order statistics associated with the inputs to be taken into account and also serves to robustify the results when the empirical data contains impulsive and colored noise and outliers. The learning rules presented are considered generalized because they can be used to implement several specialized cases including: robust PLSR, linear PLSR, weighted least-squares, and variance scaling. The same …

Neural Network Approach To The Determination Of The Geophysical Model Function Of The Ers-1 C-Band Spaceborne Radar Scatterometer, Sami M. Alhumaidi, W. Linwood Jones

Electrical Engineering and Computer Science Faculty Publications

Geophysical Model Functions (GMF) describing the relationship between the scatterometer normalized radar cross section (sigma-0) and useful geophysical parameters such as sea-surface wind vectors, wave heights, and sea- surface temperatures have been undergoing extensive research and development during the last decade. In this study, we investigate the use of two feed-forward neural networks, Multilayer Perceptron and Radial Basis Functions, for developing a useful and accurate representation of the C- band GMF. Collocated radar sigma-0 cells with global wind vector models were used as the database of the study. The resulting well-known biharmonic relationship between the sigma-0 and the relative azimuth …

A Differential Active Load And Its Applications In Cmos Analog Circuit Designs, Vladimir I. Prodanov, Michael M. Green

Electrical Engineering

In this paper we describe a CMOS differential active load and show how it can be used to create various useful structures. Tunable current gain stages and current squaring circuits are discussed. Their connection to a differential pairbased transconductor results in broad-range tunable transconductor structures suitable for adaptive continuous-time filtering applications and a four-quadrant voltage multiplier.

Evolutionary Codesign, Karthikeyan Ethirajan

Masters Theses

We present our approach to hardware/software partitioning for embedded systems based upon Evolutionary Algorithms. We have implemented it in a CAD tool, EvoC - Evolutionary Codesign which does automatic hardware/software partitioning of real-time embedded systems at the system level. Our objective is to find good design configurations that are tuned towards user's preferences. We are able to explore a large, often intractable design space using Evolutionary Algorithms while evaluating solutions having multiple and sometimes conflicting attributes in the light of Multi-Attribute Utility Theory. EvoC provides a generic format for specifying a wide variety of design problems and the implementation assumes …