Digital Commons Network^™

Utilization Of Expert Systems In The Work Place: Performing Project Software Cost Estimation On Training Systems, Henry A. Marshall

Retrospective Theses and Dissertations

This research report investigates the use of an expert system to aid project engineers at the Naval Training Systems Center in making decisions concerning the requirements of the computer systems used in simulators. For a prototype system domain, the author chose an expert system that would generate a software development cost estimate. This system questions the user about the features and options required on the training system. The expert system then analyzes the information to generate a “lines of code” estimate. A selected model will combine various factors to generate s value answer for the user. The capabilities and features …

An Experimental Study Of A Single-Phase Natural Convection In A Cylindrical, Vertical Channel, S. Ali A. Hashemi

Retrospective Theses and Dissertations

Presented in this paper is the first known experimental assessment of a single-phase natural convection in a cylindrical, vertical channel subjected to non-uniform or uniform heat flux. This work was conducted at the University of Central Florida in the College of Engineering.

The results of this experimental study were compared with theory. The experimental values of Nusselt numbers (Nu = hD/K) in the entrance and fully-developed regions were somewhat lower and higher, respectively, when compared with theory.

Noise In Interferometric Sensors, Mark Phillips

Retrospective Theses and Dissertations

A noise analysis is conducted on an interferometric sensor employed in the study of underwater acoustic noise. Primary emphasis is placed on finding the output Signal to Noise Ratio of the sensor.

Once the initial problem of the type of noise is established, the analysis proceeds along fairly classical lines. Field equations establish the signal reaching the director. Linear filter analysis establishes the nature of the spectrum after passing through a lowpass filter. Finally, second moment theory is used to derive expressions for the output Signal to Noise Ratio.

It is noted that the random ocean noise introduced to the …

Interactive Micro-Computer Software For The Production Of Engineering Drawings, Brian R. Garvey

Retrospective Theses and Dissertations

This project has developed a microcomputer-based interactive Graphics Software System for the production of engineering drawings. The drawings, stored in a digital format, can be recalled and updated much faster than by using conventional drawing methods. This allows for increased production and a standardized drawing format.

The system was designed to be easy to use so that with little training, a user can create, edit, plot, and save drawings for later retrieval. In addition, an open architecture was used in the design of the drawing database and program command structure so that the system can be easily expanded upon as …

An Inexpensive, Portable Data-Acquisition System, Ali I. Navvab

Retrospective Theses and Dissertations

Recognizing the need for an inexpensive data acquisition system, it was decided to investigate the use of the Hewlett-Packard Interface-Loop concept.

The equipment necessary to acquire, store, and display voltage/time measurements was purchased. This report discusses the integration, application, and operation of this equipment. It was found that such a system would perform satisfactorily under limited conditions but, as might be anticipated, was severely limited in frequency response. It is recommended that the system be upgraded to multi-channel capability.

Multi-Computer Communication With Crossbar Switches, Teh-Cheng Song

Retrospective Theses and Dissertations

This thesis describes the design and implementation of a MC6809 multi-computer communication system, which includes a hardware communication controller, with emphasis on the system's software development. A communication program written in 6809 assembly language has been developed to interface each user and the controller. The communication program acts as a postman, sending and taking messages for each user via the interrupt-driven sending and receiving software. A message is transmitted over a crossbar switched path, which is 8 bits wide, to increase the transmission rate and decrease dedicated CPU time. Every time MC6809 microcomputer in the system can send or receive …

Comparison Of Apodization Geometries For Bidirectional Surface Acoustic Wave Transducers Based On Efficient Track Modelling, Armando J. Vigil

Retrospective Theses and Dissertations

Apodization, or spatial overlap weighting, is a common tap weighting technique for Surface Acoustic Wave filter transducers. The two most common apodization strategies are beam centered and slant centered overlap weighting. Two lesser known apodization geometries are beam spread overlap weighting and generalized distance weighting.

A wide variety of SAW transducer weighting techniques are described. Analysis is focussed on the four apodization geometries listed above. An efficient track based modelling system is developed in order to accurately solve for the acoustic radiation profiles, apodization loss and frequency dependent acoustic conductance. This modelling system becomes the foundation for a set of …

The Application Of Systolic Architectures In Vlsi Design, Steven V. Manno

Retrospective Theses and Dissertations

Very large scale integrated (VLSI) circuit technology has offered the opportunity to design algorithms and data structures for direct implementation in integrated circuits. In order to take full advantage of this opportunity, the designer must understand the geometric limitations of the technology. Because the interconnections between components in a VLSI circuit are costly in both chip area and performance, the designer must consider the complexity of the data paths between components when selecting algorithms and architecture.

Systolic architectures offer a way to implement massively parallel special-purpose systems in VLSI circuits while minimizing costly interconnections between processing components. In a systolic …

Apodization Of Surface Acoustic Wave Three Phase Unidirectional Transducers, Benjamin P. Abbott

Retrospective Theses and Dissertations

This thesis presents an introduction to surface acoustic wave (SAW unidirectional transducer (UDT) apodization. An unbalanced apodization structure is described. The structure is shown to suffer from an unbalanced capacitive effects, significant apodization losses and passband ripple. A balanced UDT structure is developed for the purpose of improving performance and minimizing undesirable effects associated with the unbalanced structure.

Each apodization structure is analyzed and compared using a typical impulse response of a SAW transducer. The analysis is accomplished using SAWCAD2, a unidirectional Surface Acoustic Wave Computer Aided Design FORTRAN-77 program developed at the University of Central Florida. Having shown the …

Simulating The Thermal Behavior An Earth-Stationed Satellite Terminal, Anthony M. Jacobi

Retrospective Theses and Dissertations

Lumped parameter modeling using finite differencing, form the basis for a C language simulation of a thermal system. The study of the earth-stationed satellite terminal includes an introduction to the system, derivation of the governing equation, development of a simulation, and a comparison of the results to empirical data.

The analysis is undertaken with emphasis on the worst-case thermal environment, and with determination of the cooling loads and transient response as primary goals. Comparing the predicted cooling loads to empirical data, and previous analyses, indicates an accurate simulation has been constructed. The computer models are offered as an alternative method …

The Application Of Expert Systems To Automated Storage And Retrieval, Robert E. Mcdonald

Retrospective Theses and Dissertations

This report discusses the major functions, decisions, and strategies of automated storage and retrieval systems (AR/RS). The report surveys the essential features of expert systems and discusses how they can be applied in automated warehousing environments. A blackboard expert system architecture was examined and found to be a flexible and responsive control system for automated warehousing applications. A simple AR/RS expert system was constructed using an expert system software package. A warehousing simulation was performed which compared the expert system’s performance to a typical AR/RS control system. The expert system produced increased efficiency of operation because of the intelligent rules …

On-Line Microprocessor Control Of Optical Disc Recorders And Players, Howard Luebcke

Retrospective Theses and Dissertations

The goal of this paper is to document the work performed in the development of the software required to operate a video disc player and recorder in the on-line mode using a portable computer. Applications of video disc systems are discussed as are future improvements to the developed system.

This paper also includes a description of the hardware, functional requirements and design of the software, and the end result of the development of the software in the form of program listings.

Electromagnetic Scattering From Stacked Gratings, Pok K. Kwan

Retrospective Theses and Dissertations

The theory of scattering matrices and microwave network analysis are employed to solve the problem of scattering from cascaded infinite periodic gratings. The total reflection and transmission coefficients are calculated as functions of angle of incidence, wire spacing for each grating, grating separation, wire thickness, and number of gratings that comprise the cascaded structure. Moreover, the problem of stacking dielectric slabs with periodic gratings is formulated and solved. In all cases, the Secant Corrector Spectral Iteration approach is used as a numerical method for calculating the desired currents and fields.

Finally, calculated values of the reflection and transmission coefficients are …

Pulse Width Modulated Adaptive Delta Modem Design And Analysis, Gregory L. Milne

Retrospective Theses and Dissertations

A unique design of a voiceband adaptive delta modem will be presented. The modulator utilizes a constant amplitude variable width pulse combined with the principles of delta modulation. This results in a modem that has lower amplitude distortion, requires less transmission channel bandwidth, and is less prone to slope overload than conventional adaptive delta modems. The design also allows the use of a simple single integration demodulator while maintaining fidelity.

The modem design and analysis is presented assuming a transmission channel which is bandwidth limited and amplitude limited.

Phase-Locked Loop Based Oscillator Phase Noise Measurement Technique, Luis M. Jimenez

Retrospective Theses and Dissertations

Oscillators play an important role in the performance of various radio frequency (RF) systems. The generation of stable carrier and clock frequencies is necessary at both the transmitter and receiver ends of a communication system. Phase noise is the parameter used to characterize an oscillator frequency stability. This thesis introduces a phase noise measurement technique using a phase-locked loop. A 100 MHz Colpitt’s oscillator, for the phase noise source, was designed and built. The output of the oscillator was mixed down to 10 MHz, before a phase-locked loop extracted the phase noise information. Measurements were taken at RF frequencies using …

Master Of Science In Computer Based-Learning, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Accidents Types Des Monteurs De Lignes Du Secteur De La Construction (Annexe), Évelyne Kedl, Lucie Laflamme, Lyne Marinacci

Rapports de recherche scientifique

La première phase du projet dont il est ici question vise à résumer, en un nombre limité d’accidents types, les circonstances dans lesquelles les monteurs de lignes se blessent le plus souvent et les caractéristiques les plus courantes de leurs lésions. À cette fin, les fichiers "pairés" d’accidents des trois entrepreneurs participants et de la CESST ont servi à décrire 236 accidents en utilisant un total de 15 variables. Le traitement de ces données, rétrospectives, a conduit à la reconstruction de six classes d’accidents différentes les unes des autres.

Ces classes se distinguent d’abord par le genre de l’accident. Nos …

An Algorithm For Resource Allocation Requiring Low Overhead Communication, Ann Marks

Computer Science Technical Reports

A heuristic algorithm for allocating resource units to sites in a distributed system is presented. Starting with a given allocation of sites, the algorithm performs a series of optimizations involving pairs of sites in an attempt to improve the worst pair-wise imbalance present in the system; termination occurs when no further improvement is possible. After outlining the general form of the algorithm, which effectively defines an entire family of algorithms, we present theoretical results that speak to the performance of the algorithm as measured in the number of optimizations that can be done, the amount of control communication required and …

Catastrophic Damage From Dam Break Floods, L. Douglas Jemes, Al-Hassan Sumani, Melanie L. Bengston

Reports

No abstract provided.

Master Of Science In Computer-Based Learning With Specialization Areas In Adult Education, Electronic Education, Training And Learning 1986-87, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Department Of Computer Science Master Of Science Computer Science 1986-1988, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Computer-Based Graduate Programs In Computer Education 1986-87 Catalog, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Doctor Of Science In Computer Science 1986-88 Catalog, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Doctor Of Art In Training And Learning, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Doctor Of Arts In Information Science Catalog, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Reaction During Sintering Of Barium Titanate With Lithium Fluoride, Jyoti P. Guha, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

The reactions occurring during sintering of stoichiometric BaTiO₃ with small additions of LiF were studied at temperatures between 700° and 900°C. BaTiO₃ reacts with LiF to form a cubic solid solution and Li₂TiO₃ During sintering, the cubic solid solution coexists with Li₂Ti0₃ and forms a liquid phase at 740°± 5°C. The occurrence of a liquid phase at this temperature results in an enhancement of the sintering process and leads to the development of a highly dense microstructure. Copyright © 1986, Wiley Blackwell. All rights reserved

Glass Experiments In Space, Norbert J. Kreidl

Materials Science and Engineering Faculty Research & Creative Works

Current and potential glass research under microgravity includes studies of minimum cooling rate, homogeneous nucleation, diffusion, surface tension and enrichment, fining without buoyancy, avoidance of liquid phase separation, gel synthesis, composites and uniform micro balloons. The experiments do not just anticipate space fabrication but will also provide information and innovation encouraging advanced processing on earth. © 1986.

Switched-Capacitor Programmable Sallen And Key Lowpass Filters, Karl P. Eriksson

Retrospective Theses and Dissertations

This thesis deals with a different approach to switched-capacitor filters than previously seen by the use of a Sallen and Key topology. It is shown that a Sallen and Key second-order topology approach to a switched-capacitor filter gives reasonable filter performance results, contrary to what the literature leads one to expect. It is also shown that the Sallen and Key second-order topology with modification to a third-order section with buffers results in a high performance switched-capacitor filter with fewer components than previous switched-capacitor filters. This results in fewer monolithic chip size requirements, reduced power requirements, and less cost. Higher order …

Direct Digital Control Of A Liquid Level/Temperature Control Unit, Pedro J. Claudio

Retrospective Theses and Dissertations

A direct digital control algorithm was implemented on a liquid level and temperature control unit. Two control schemes were implemented on the system and the results were compared against a fourth order Runge-Kutta solution.

Both control schemes involved proportional feedback with dynamic adjustment of the operating point. It was found that the control scheme that contained a feedforward component which dealt with the inlet water temperature had a superior dynamic response to setpoint changes. Steady state offsets in both control schemes were attributable to model parameter estimation errors. Differences between the actual and predicted system dynamic response were also attributable …

A Peripheral Subsystem Optimized For Computer Image Generation Applications, John J. Bloomer

Retrospective Theses and Dissertations

Requirements for ever increasing realism in real time computer image generation for military mission and commercial training, have generated the need for a higher performance, more cost effective front-end processor. Current computer image generators front-end general purpose computers are reaching their performance limits in current architectures.

The tasks of this processor include: realtime computations, magnetic disk control, data transfer and direct memory access to and from the balance of the image generator. A new front-end processor system is under development. This multiple-bus, multiprocessor architecture in and of itself does not address disk and external data transfer. A peripheral subsystem is …