Digital Commons Network^™

A Comparison Of Two Microcomputer Continuous Simulation Languages, Amy Brannon Kirkland

Retrospective Theses and Dissertations

Until the early 1980s, most digital simulation models of reasonably complex systems required the use of a mainframe for a solution to be obtained in a timely manner. Recently, the declining prices of computer memory, operating systems, and modern hardware have supported the implementation of large simulation packages on smaller machines. Today, tremendous improvements in the performance of microcomputers have provided the simulationist with a completely personalized, less expensive computing environment. Operating within a microcomputer environment, the simulationist must choose a suitable computer language. Often, user familiarity dictates the selection of a language, while other factors such as ease of …

Comparison Of Graphical Design Methodologies, Pamela Stark Woodard

Retrospective Theses and Dissertations

The recent development of the Ada language by the Department of Defense and its required use within the Department of Defense for the development of embedded software systems has resulted in a need for better methods to represent Ada software designs. Graphical design techniques have long been used as software design and documentation aids. The use of graphical techniques to illustrate an Ada design can provide a clear, concise means to describe a complex software system. The purpose of this paper is to investigate several software design methodologies which incorporate graphical design notations. The specific software methodologies examined in detail …

Numerical Analysis Of The Resonant States Of Quantum Wells And Superlattice Devices, Alan Gilbert Whittaker

Retrospective Theses and Dissertations

This thesis is concerned with the development of a numerical model to describe the resonant states associated with quantum well and superlattice devices. A numerical method is described where the time-independent Schrodinger equation is represented as a series of simultaneous algebraic equations using the finite-element method. The eigenvalues for these equations are then found using a Sturm sequence, and the eigenfunctions subsequently calculated using a reverse iteration method containing orthogonality constraints. Simulations of specific devices are presented and compared with experimental results and good correlation is observed.

Investigative Study Of The Reliability Of A Rotating Turbine Blade, William Stuart Beal

Retrospective Theses and Dissertations

-Turbine blading incidents are a concern to electrical utilities since they can result in power plant unavailability. The reliability of a particular turbine blade is investigated in this report to determine if it can be replaced with a more reliable blade design. The majority of incidents concerning this blade have been attributed to stall flutter vibration that has been the result of unit operation at low load levels with high back-pressures in the steam condenser. Stall flutter can be avoided by limiting back-pressure levels during low load operation and is thus not a concern here. Another potential cause of unreliability …

An Overview Of Machine Vision, Juan C. Telchi

Retrospective Theses and Dissertations

The objective of this paper is to examine new ideas and other useful information on the most recent advances in the robotic vision field. A visual system model was introduced and the basic components of this model were explained. The principal areas in robotic vision were researched. This included two dimension and three dimension vision sensors. Industrial applications and future developments of machine vision systems were addressed. A survey was done to summarize the vision system market and the robot market share worldwide.

Polar Spectrum Coding, Daniel Harris Chapman

Retrospective Theses and Dissertations

Polar Spectrum Coding is a novel speech coding algorithm for narrowband voice communications. A polar Fourier transform of the signal is computed, and the magnitude and phase of the speech spectrum is encoded for transmission. The correlation between frames of speech signals is exploited to minimize the transmission rate required for intelligible speech. At the receiver, the encoded words are decoded and the spectrum reconstructed. An inverse Fourier transform is performed, and the result is the reconstructed speech waveform. Polar Spectrum Coding theory is explained. The sensitivities of various parameters on performance are explored, and performance in the presence of …

Analysis Of Phase Noise In Phase Lock Loop, Diane Marie Pavik

Retrospective Theses and Dissertations

This research report presents an introduction into phase lock loops (PLL) with a major emphasis on calculating phase noise in frequency synthesizers. A PLL model that incorporates the major sources of noise is presented for the purpose of design analysis. The model can be used to analyze second and fifth order PLLs which allows the accurate calculation of phase noise as a function of independent variable design parameters. The stability of PLLs is also analyzed to show the effects of a marginally stable system on the resultant phase noise. Developing an accurate PLL model which accounts for the major sources …

Impulse, Janet Blank-Libra, Bridget Hurney, Jennifer Pint, Virginia Wishard, Wendy Wood

Impulse (Jerome J. Lohr College of Engineering Publication)

No abstract provided.

Applications Of Lattice Filters To Quadrature Mirror Filter Banks, Gregory R. Jaspers

Retrospective Theses and Dissertations

Presented is a method for designing and implementing lattice filters to be used in Quadrature Mirror Filter (QMF) Banks. Quadrature Mirror Filter Banks find use in applications where a signal must be spilt into subbands operated on then reconstructed in the output. Because of their structure, lattice filters do this very well and allow perfect reconstruction, even when the lattice coefficients must be quantized. In this paper QMF's and Lattice Filters are derived and analyzed. Application of the lattice filter is presented along with a design program and example of its use to implement a QMF. The computer aided design …

An Ada Simulator For The Structured Functional Simulation Of A Digital Signal Processing System, Christopher Paul Roney

Retrospective Theses and Dissertations

A behavioral-level simulator designed for FIRST, a silicon compilation system for digital signal processing, is implemented in the Ada* programming language. The simulator accepts as input a digital signal processing system description written for the FIRST ([ast Implementation of aealtime ~ignal transforms) silicon compiler, and provides an interactive post-processing signal trace facility. The simulator is a time-driven simulator which contains a FIRST description language parser, a subset of the FIRST primitives, and the capacity for maintaining a full history of all signals in the system. The primitives in the FIRST description language are common to digital signal processing systems (e.g., …

Lansim: A Simulation Package For Estimating Performance Characteristics Of A Class Of Local Area Networks, Gregory Charles Buchner

Retrospective Theses and Dissertations

ABSTRACT During recent years, the trends in computer resource organization have seen the replacement of the traditional mainframe computers and their timesharing terminals with individual desktop workstations. These workstations can offer more computational power than the mainframes of less than a decade ago. With this distribution of processing from the more traditional mainframe computer comes the need to share peripheral resources among these desktop workstations. These include items such as file systems, tape drives, printers, plotters, and graphics display devices. A common way to share these among the multi-computer environment is to provide a transparent gateway that allows each workstation …

Display Peripheral For A Flight Simulator Using A Three-Dimensional Computer-Controlled Motor Driven Model, Kenneth Randall Flowers

Retrospective Theses and Dissertations

The flight simulator display peripheral, described herein, provides the visual aide necessary for observation of effects due to operator responses for any aircraft simulator which prohibits the observers from occupying space within the cockpit of the simulator.

This display peripheral is provided by a three-dimensional, computer-controlled, motor-driven model which duplicates the angular movements generated by the aircraft simulator by moving a model aircraft mounted within a clear plastic ball.

The display utilizes a Motorola 68000 educational computer board to translate the three aircraft angles. pitch, yaw and roll received from the aircraft simulator via an RS-232C compatible serial asynchronous communication …

Corvette Specs And Technologies Zr-1 Automobile, Kentucky Library Research Collections

Research Collections

Reports from Corvette management in Michigan noting the changes and upgrades in the 1988-1989 Corvettes, LRT and ZR1 with motor, body and technical upgrades. Also there is a breakdown of thefts for the Corvette noting the difference after the Pass-Key function was added. Bowling Green, Kentucky plant's training, job performance and community activities are also noted for 1988-89.

Laser Induced Darkening Semiconductor Dope Glasses, Jayant Malhotra

Retrospective Theses and Dissertations

No abstract provided.

In-Situ Stress Orientation And Magnritjde At The Fenton Geothermal Site, New Mexico, Determined From Wellbore Breakouts, Colleen A. Barton, Mark D. Zoback, Kerry L. Burns

United States Department of Energy: Publications

The acoustic borehole televiewer provides excellent data for the detection and measurement of stress-induced wellbore breakouts. Analog televiewer data from the Fenton Geothermal well EE-3 in New Mexico were digitized and interactivly processed for detection and analysis of azimuth and shape of stress-induced breakouts occurring in the well at depths of about 2.9 - 3.5 km. A statistical analysis of the measured breakout azimuths yields a well resolved orientation of least horizontal principal stress of 119 °, consistent with least principal stress data from the Rio Grande Rift. As the magnitude of the least horizontal compressive stress, ^Shmin, in …

Master Of Science In Computer Science Catalog, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Center For Computer Science Master Of Science Computer Science 1988-89, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

M.S. Course Schedule April 4, 1988-June 24, 1988, Nova University

College of Engineering and Computing Course Catalogs

No abstract provided.

Computer-Based Doctoral And Master's Programs For Professionals Delivered Through Unix 1988, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Doctor Of Arts In Information Science Interim Catalog 1988, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Doctor Of Education In Computer Education, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Development Of Techniques To Perform Simulation-Adaptation In A Simulation Training Environment Using Expert System Methods, Cheryl E. Bagshaw

Retrospective Theses and Dissertations

The use of computers for instructional purposes is steadily increasing, along with an emphasis on developing systems which create environments tailored to human beings. Artificial Intelligence techniques have been incorporated into these systems with an aim at developing better methods of modeling of simulating knowledge and intelligent behavior. One type of these systems, Intelligent Simulation Training Systems (ISTS), utilize a simulation in the training process. This is an ideal environment for the instruction of skills which focus on the ability to understand the time and space relationships of objects.

An intelligent tutor module of an ISTS must configure scenarios for …

A Student Performance Evaluation Method For An Intelligent Simulation-Based Tutoring System, Camille Marie Dixon

Retrospective Theses and Dissertations

Intelligent simulation-based tutoring systems (ISTS) present intriguing and complex environments for the training of high performance skills. These skills involve the manipulation of objects within time and space constraints.

As with any tutoring system, there must exist a performance measurement methodology. Within an ISTS there is a module which functions as a tutor and a module which functions as a student modeler. These fundamental modules are required to make effective individualized tutoring decisions. However, each of these modules rely on information from a performance measurement system or evaluation system.

The objective of this research was to establish a performance evaluation …

A New Method For Broadband Surface Acoustic Wave Diffraction Analysis, Jacqueline Hanvey Hines

Retrospective Theses and Dissertations

This thesis describes an innovative technique for determining the impulse response of a SAW device including the effects of diffraction on both isotropic and anisotropic substrates. The approach presented is unique in that it determines the point-to-point impulse response for the isotropic case using the two-dimensional wave equation, and utilizes a double integral reduction technique to determine the tap-to-tap response, thereby significantly reducing the complexity of the calculations involved. An extension is then made to describe the impulse response of two cascaded transducers of arbitrary geometry, along with some simplifying cases. Previous attempts to model diffraction effects generally utilized either …

Direct Digital Control Of A Liquid Level Control Unit, Barbara Viehman Lytle

Retrospective Theses and Dissertations

A system was developed to allow undergraduate engineering students the capability of simulating various types of control modes in a laboratory environment. The use of digital control and common industrail components such as transducers, recorders, and valves was implemented.

Modification to an existing bench scale process control system is outlined and demonstrated. A computer program was written which interfaces with the hardware and data acquisition software allowing the user many options to study control processes under a variety of conditions. A wide range of parameters can be selected. System parameters can be saved on disk or printed directly. Data are …

Optical Interferometric Formation Of Phased Array Antenna Footprint/, John E. Sherwood

Retrospective Theses and Dissertations

A 40 dB gain RF Low Noise Amplifier (LNA) matched to a photodiode input is designed using TOUCHSTONE (S-parameter based CAD software), built, and tested. The RF LNA formed the detector of a Mach-Zehnder interferometer constructed with single mode fiber, coupler, Gradient Index Rod Acousto-optic modulator (ADM) . (GRINROD) lenses, and an The ADM is used to frequency shift the optical frequency by 125 MHz, and the motion of a GRINROD lens is used to produce an optical phase shift that is recovered at the detector as an electrical phase shift by using heterodyne detection . Finite Hankel transforms are …

Development Of A Prototype System For Snow Route Design And Management, J. R. Wright

JTRP Technical Reports

No abstract provided.

An Investigation Of The Micro-Surfaces Of Fiber Glass, Window Glass, Bottle Glass, And Quartz Crystal Through The Use Of Scanning Electron Microscopy, Raymond C. Friedrichsen

Graduate Research Papers

The problem of this study is to investigate the surfaces of quartz crystal, bottle glass, window glass, and fiber glass, to determine if there are any substantial differences in their structures when compared to a fiber optic material. The investigation will be done with the aid of the scanning electron microscope {SEM).

Rise Time To Frequency Correlation Of Crosstalk In Coupled Microstrip Lines, Charles Michael Fletcher Jr.

Retrospective Theses and Dissertations

An examination of forward crosstalk in microstrip transmission lines is presented through a computer simulation using SPICE. A non-resistive lumped L-C transmission line model is modified to include capacitive and inductive coupling from adjacent lines. Two adjacent microstrip transmission lines are modeled, and simulation results in both the time and frequency domains are shown. The time domain or transient analysis looks at the effect of rise times on crosstalk. Rise times in the range of 100 to 1000 nanoseconds (ns) are considered. The frequency analysis shows the crosstalk frequency response over the range of 100 to 1600 kilohertz (kHz). The …

A Study Of The Reaction Kinetics For The Thermal Oxidation Of Dilute N-Heptane Vapors In A Plug Flow Reactor, Steven Hunter Ramsey

Retrospective Theses and Dissertations

During August through October, 1986, experiments were conducted with the aim of devel oping kinetic relationships for the thermal oxi dation of dilute n-Heptane vapors in air using a Lindberg tube furnace reactor. This project was designed to be the first step in the ultimate goal of research ing the effe cts upon the combustion of dilute organic vapors when certain chemicals are added to the combustion stream. These chemicals are postulated to form free radicals and thus enhance the oxidation of organ i cs . Comparison of the kinetics before and after the addition of t he free radical …