Engineering Commons^™

Adaptive Gain Control And Contrast Improvement For Medical Diagnostic Ultrasound B-Mode Imaging System Using Charge-Couples Devices, Alan W. Bryant, Thomas J. Herrick

Electrical and Computer Engineering Faculty Research & Creative Works

A B-mode ultrasound imaging system operates by transmitting a high-frequency sound pulse and measuring the strength and time of flight of the reflected signal. The ultrasound signal may be attenuated as much as 60 dB in its round trip to a target and must be normalized so that contrast is not lost in the far field. Manual controls for adjusting receiver gain versus depth are common in many clinical uses but are impractical in most surgical applications. The goal of this project was to design a circuit to automatically adjust the gain. A two-dimensional low-pass filter is used to approximate …

Analysis Of Shear Banding In Plane Strain Compression Of A Bimetallic Thermally Softening Viscoplastic Body Containing An Elliptical Void, Z. G. Zhu, R. C. Batra

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We study plane strain thermomechanical deformations of a prismatic viscoplastic body of square cross-section and deformed at a nominal strain-rate of 5000 s-1. The body has two thin layers placed symmetrically about the horizontal centroidal axis and an elliptical void at the center. The major axis of the void coincides with the vertical centroidal axis and also with the direction of loading. The layer material differs from that of the body in only the value of the yield stress in a quasistatic simple compression test. The yield stress for the layer material is taken to be either one-fifth or five …

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

Electrical and Computer Engineering Faculty Research & Creative Works

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

Information Technology And Wealth: Cybernetics, History And Economics, Elin Whitney-Smith

Engineering Management & Systems Engineering Theses & Dissertations

Capitalism developed where and when it did because there was high information access. There was high information access because of a major advance in information technology--the press. Where the technology was not controlled by the "powers that be" there was economic growth and a shift in the entire social structure. Where it was controlled there was no structural change and there was economic ruin. The development of capitalism is a major step change in economic growth. It is also a major change in the way people organize themselves into groups.

Major step changes in the growth and in the organization …

Web Crippling Behavior Of Sections With Web Openings, Wei-Wen Yu, James E. Langan, Roger A. Laboube

CCFSS Library (1939 - present)

No abstract provided.

Continuum Modeling Methodology For Dynamic Behavior Of Towers, Khaled A. Obeid

Civil & Environmental Engineering Theses & Dissertations

A very common problem in Civil Engineering is the analysis and design of lattice structures. These types of structures generally consist of repetitive sections and have been utilized in the erection of transmission and communication towers, space roof trusses, solar energy collectors, and space platforms. Since lattice structures consist of a significantly large number of members and subsequently a large number of nodes, the classical discrete technique of analysis can be very expensive even on today's modern computers. This study applies a rational approach which capitalizes on the repetitive nature of towers to develop the equivalent continuum model for the …

A Technological Development Model For Strategy Formation, Halvard E. Nystrom

Engineering Management and Systems Engineering Faculty Research & Creative Works

Summary form only given, as follows. The author presents a technological development model for product and company development based on a distinction between explicit and implicit technologies. Implicit technologies are evolving technologies while explicit technologies are established technologies. Based on empirical data from Swedish companies, a number of strategic dimensions are discussed such as network interaction and combining knowledge from various sources. These concepts are then used to present an integrated model of strategy formation and product and company development. It is argued that this view of technological development facilitates the understanding and analysis of innovation and entrepreneurship in highly …

An Empirical Analysis Of Backpropagation Error Surface Initiation For Injection Molding Process Control, Alice E. Smith, Elaine R. Raterman, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Backpropagation neural networks are trained by adjusting initially random interconnecting weights according to the steepest local error surface gradient. The authors examine the practical implications of the arbitrary starting point on the error landscape of the ensuing trained network. The effects on network convergence and performance are tested empirically, varying parameters such as network size, training rate, transfer function and data representation. The data used are live process control data from an injection molding plant

Dose Rate Determination Of The Highly-Enriched Uranium Fuel At The University Of Missouri-Rolla Reactor In Preparation For Transportation, Alice Ann Netzer

Masters Theses

"An analytical model was developed in order to accurately estimate the dose rates in air of the highly-enriched uranium (HEU) fuel at the University of Missouri - Rolla Reactor. Based upon these results, a method is proposed to remove the fuel from the reactor.

First thermoluminescent dosimeters (TLDs) were exposed under water to each of the fuel elements in the reactor pool, except for the four control rodded elements. A model was developed to use the in-water TLD readings to calculate the dose rate of the fuel elements in air at 1 foot and 3 feet. The fuel was modeled …

Micromechanics Of Granular Materials And Its Relation To Wave Velocity, Tarun K. Agarwal

Civil & Environmental Engineering Theses & Dissertations

The macro characters of the granular materials depend upon micromechanical parameters such as the void ratio, particle shape, contact force distribution, and initial state of the fabric of the assembly. Since it is difficult to evaluate these internal parameters from laboratory experiments, a macro measure is desired which depends directly on these internal parameters. One such measure has been shown to be dynamic shear modulus but it was incomplete in predicting directional changes in the internal parameters. Therefore, it is hypothesized here that the complete elastic moduli matrix will have more direct information about the internal parameters, especially the dynamic …

Numerical Modeling Of Flame Lift-Off Phenomenon And Calculation Of Thermal Loads On A Methane Fuel Injector With Complex Geometry, Taj O. Mohieldin

Mechanical & Aerospace Engineering Theses & Dissertations

A numerical study has been conducted to analyze a fuel injector with three in-line cylinder geometry that has been adopted as a model for investigating the combustion phenomenon in the 8-Foot High Temperature Tunnel (HTT) combustor at the NASA Langley Research Center. The primary objective here is to analyze the flame lift-off phenomenon in the three cylinder fuel injector geometry in two-dimensions. The fluid mechanics model used in the analysis includes time-averaged Navier-Stokes equations that are employed in conjunction with a two-equation k-$\epsilon$ model for predicting the effects of turbulence. Calculations were performed with three chemistry models, namely fast chemistry, …

A Practical Parallel Algorithm For The Minimization Of KröNecker Reed-Muller Expansions, Paul John Gilliam

Dissertations and Theses

A number of recent developments has increased the desirability of using exclusive OR (XOR) gates in the synthesis of switching functions. This has, in turn, led naturally to an increased interest in algorithms for the minimization of Exclusive-Or Sum of Products (ESOP) forms. Although this is an active area of research, it is not nearly as developed as the traditional Sum of Products forms. Computer programs to find minimum ESOPs are not readily available and those that do exist are impractical to use as investigative tools because they are too slow and/or require too much memory. A practical tool would …

Neural Network Character Recognition With A 2-D Fourier Transform Preprocessor, Daqiao Du

Dissertations and Theses

In pattern recognition applications, it is usually important that the same identification be given for a pattern, independent of a variety of positions, rotations and /or distortions of the pattern within the recognition device's field of view. This research relates to development of a preprocessor for a neural network character recognition system, where the role of the preprocessor is to assist in minimizing the difficulties related to variations of position and rotations of a character within the field of view. The preprocessor explored here was suggested in 1970' (Lendaris & Stanly, 1970), and is implemented here with more recent advances …

Analysis Of A Coordination Framework For Mapping Coarse-Grain Applications To Distributed Systems, Linda Ruth Schaefer

Dissertations and Theses

A paradigm is presented for the parallelization of coarse-grain engineering and scientific applications. The coordination framework provides structure and an organizational strategy for a parallel solution in a distributed environment. Three categories of primitives which define the coordination framework are presented: structural, transformational. and operational. The prototype of the paradigm presented in this thesis is the first step towards a programming development tool. This tool will allow non-specialist programmers to parallelize existing sequential solutions through the distribution, synchronization and collection of tasks. The distributed control, multidimensional pipeline characteristics of the paradigm provide advantages which include load balancing through the use …

Second Coefficient Of Viscosity In Air, Robert L. Ash, Allan J. Zuckerwar, Zhonquan Zheng

Mechanical & Aerospace Engineering Faculty Publications

Acoustic attenuation measurements in air were analyzed in order to estimate the second coefficient of viscosity. Data over a temperature range of 11 C to 50 C and at relative humidities between 6 percent and 91 percent were used. This analysis showed that the second coefficient of viscosity varied between 1900 and 20,000 times larger than the dynamic or first coefficient of viscosity over the temperature and humidity range of the data. In addition, the data showed that the molecular relaxation effects, which are responsible for the magnitude of the second coefficient of viscosity, place severe limits on the use …

Electrode Kinetics Of Oxygen Reduction In Lithium Carbonate Melt: Use Of Impedance Analysis And Cyclic Voltammetric Techniques To Determine The Effects Of Partial Pressure Of Oxygen, Bhasker B. Davé, Ralph E. White, Supramanian Srinivasan, A. John Appleby

Faculty Publications

The effects of the partial pressure of oxygen and temperature on the oxygen reduction on a submerged gold electrode in a lithium carbonate melt were investigated using cyclic voltammetry and impedance analysis. The values for the mass-transfer parameters, DC_O, obtained from cyclic voltammetry and impedance analysis were in good agreement. The reaction orders for oxygen at 800°C were calculated to be about 0.3 for the exchange current density and 0.5 for the product DC_O; these values are consistent with the mechanism proposed in the literature for oxygen reduction in Li₂CO₃ melt.

Modification Of Newman's Band(J) Subroutine To Multi-Region Systems Containing Interior Boundaries: Mband, D. Fan, Ralph E. White

Faculty Publications

Newman's BAND(J) subroutine, which has been used widely to solve models of various electrochemical systems, is extended to solve a system of coupled, ordinary differential equations with interior boundary conditions. A set of coupled, linear ordinary differential equations is used to demonstrate the solution procedure. The results show that the extended technique has the same accuracy as that of using pentadiagonal BAND(J), but the execution speed is about five times faster than that of pentadiagonal BAND(J). Using sparse matrix solver Y12MAF to solve the same set of equations takes even longer time than pentadiagonal BAND(J).

Impedance Analysis For Oxygen Reduction In A Lithium Carbonate Melt, Bhasker B. Davé, Ralph E. White, Supramaniam Srinivasan, A. John Appleby

Faculty Publications

Oxygen reduction on a smooth gold electrode in a pure lithium carbonate melt was investigated by electrochemical impedance spectroscopy and cyclic voltammetry. The impedance data were analyzed using the Randles-Ershler equivalent circuit to determine parameters such as the charge-transfer resistance, Warburg coefficient, double-layer capacity, and uncompensated electrolyte resistance. The parameters estimated by complex plane plots and a complex nonlinear least squares method are in good agreement. Cyclic voltammetric measurements showed that oxygen reduction in a lithium carbonate melt is very rapid. A mass transfer parameter, DC₀, estimated by the cyclic voltammetry concurred withthat calculated by the electrochemical …

Electrochemical Characterization Of Electronically Conductive Polypyrrole On Cyclic Voltammograms, Taewhan Yeu, Ken-Ming Yin, Jose Carbajal, Ralph E. White

Faculty Publications

Experimental and theoretical cyclic voltammograms for electronically conducting polypyrrole film are obtained from the identical conditions and compared to each other to characterize electrochemical behavior of the polymer. A comparison of the simulated and experimental cyclic yoltammograms shows quantitative agreement. The profiles of the dependent variables show that the switching process is governed by the availability of the counter ion to the polypyrrole electrode and the amount of electroactive sites. Sensitivity analysis shows that the double layer effects have more influence in the cyclic voltammograms than the electrokinetic effects.

In Situ Degradation Of Polyhalogenated Aromatic Hydrocarbons By Electrochemically Generated Superoxide Ions, E. E. Kalu, Ralph E. White

Faculty Publications

The reduction of dioxygen in aprotic media yields superoxide ions which react with polyhalogenated aromatic hydrocarbons by nucleophilic substitution. The degradation of hexachlorobenzene to bicarbonates and chlorides using in situ generated superoxide ions was carried out at room temperature in a flow cell system equipped with a gas fed, porous electrode. The effects of current, electrolyte flow, and aprotic media on the extent of degradation of hexachlorobenzene are presented.

On Local Stresses And Spring Constants Of Pipe-Nozzle Connection, Hson-Chih Sun

Dissertations

This thesis presents a comprehensive study of local stresses and spring coefficients of pipe with a nozzle connection, analyzed by the finite element method (FEM). Six types of loading are discussed: radial force, circumferential moment, longitudinal moment, circumferential shear force, longitudinal shear force, and torsional moment.

For the local stresses, the bending and membrane stress factors due to each of these loadings are presented in a series of plots with various gamma (piping radius/thick-ness) and beta (nozzle radius/pipe radius) values. These stress factors will readily replace those previously published in WRC No. 107. This work not only gives more accurate …

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

Theses

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

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

Simulation Based Modeling And Scheduling Of A Generalized Flow- Line, Srinivas Anne

Theses

Simulation is a state of art technique, widely used to analyze the behavior of complex and dynamic real time systems. This study consists of two parts. The first part involves in the development of a simulation model of a real time flow line, used to assemble Printed Circuit Boards. The desired performance measures of the system, like, utilization, starving, blocking, failure and maintenance are recorded. The model developed can be used as a test pad to analyze scheduling rules and heuristics. This is illustrated in the second part of the study which consists of studying the behavior of the Apparent …

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

Theses

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

A Pc Based Computer Model With A Postprocessor For The Movement Of Groundwater, Joseph Byra

Theses

Currently available computer programs that model groundwater flow are inherently limited in their capabilities, in one way or another. Additionally, many of these computer programs are relatively inaccessible to the general user because they operate off of mainframe computers and sophisticated plotters. As a result, a simple to use computer program called 2DFLOW has been modified so it can be run on a personal IBM compatible computer. It models steady-state fluid flow through saturated porous media. In addition, a postprocessor called 2DPLOT has been developed. The postprocessor generates the equipotential contours and the flux vectors that describe the physics of …

Digital Correlators For Spread Spectrum Communications, Raymond B. Chadwick

Theses

The design and application, in spread spectrum communications, of a digital correlator implemented in a Xilinx Field Programmable Gate Array is presented. Spread spectrum communications, correlators and Xilinx Field Programmable Gate Arrays are first introduced. A digital correlator is designed and implemented in a Xilinx Field Programmable Gate Array. Cascading correlators to increase the correlation dimensions is next explored. The maximum operating frequency of the digital correlator is calculated and simulated to be 40 Mhz; a significant speed improvement over commercially available correlators such as those from TRW.

Molecular Modeling Studies Of Anatoxin Agonist Analogues, Qizhan Yao

Theses

Thirty two anatoxin agonist analogues were investigated by means of computerassisted molecular modeling studies to delinate factors that may contribute to potency. The structures were generated from the fragment libraries from the SYBYL program, and minimized by the MM2 program. Then a systematic conformational search was done based on the global minimized structures to get bioactive conformations.

Ten agonists were further studied after the conformation optimization. The most potent agonists among these analogues, (+)-anatoxin-a (11), about 300 times as potent as carbamylcholine, severed as a template for the rest to examine the superimposability of the hydrogen bonding acceptor site and …

A Study Of Machining Parameters To Optimize Surface Finish In Metal Cutting Through Cnc, S. Waseem H. Zaidi

Theses

The purpose of this thesis is to find the relationship between surface finish and machining parameters. A series of experiments have been performed at shop floor of NJIT, on MAZAK(CNC turning center), using two different cutting tool materials(high speed steel and cemented carbide) and a workpiece of Aluminium. The results have been then evaluated and analyzed to see the effects of various combinations of cutting conditions, that is, feed, speed, and depth of cut. Recommendations have been made on the basis of analysis to estimate the minimum and maximum values of surface roughness with respect to the cutting conditions for …

Recovering Surface Structure Using Direct Method, Zhu Ying

Theses

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

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

Theses

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

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