Engineering Commons^™

Real-Time Flight Simulation And The Head-Mounted Display - An Inexpensive Approach To Military Pilot Training, Philip A. Platt

Theses and Dissertations

The integration of the low-cost head-mounted display (HMD), an inexpensive graphics workstation-based flight simulator, and a communications network was investigated to determine if the prototype of an inexpensive multi- aircraft Virtual Flight Simulator could be built. Previous research efforts have coupled HMD technology and flight simulation; however, the cost of these systems has been high. This thesis effort emphasized the use of joystick devices to emulate pilot control, the implementation of a fully enclosed virtual flight simulator, and the utilization of low-cost NTSC-based television technology to produce a prototype. The virtual flight simulator also contained a basic set of instruments …

An Evaluation Of An Ada Implementation Of The Rete Algorithm For Embedded Flight Processors, F. Jesse Fanning

Theses and Dissertations

The purpose of this thesis was to design and develop an expert system shell in Ada, and to evaluate the shell's execution and size performance to determine its suitability for real-time operation on the MIL-STD-1750A embedded flight processor. The expert system shell uses the CLIPS/Ada inference engine, a forward-chaining Ada implementation of Rete. The expert system shell design is presented along with an overview of the target environment--the MIL-STD-1750A VHSIC Avionic Modular Processor (VAMP) running under the Ada Avionics Real-Time Software (AARTS) Operating System. Theoretical and empirical complexity analyses of the inference engine are presented and discussed in view of …

Fluorescent Lifetime Measurements Of Rare Earth Elements In Gallium Arsenide, Danny J. Topp

Theses and Dissertations

Lifetime measurements of the excited states of three GaAs semiconductors doped with the rare earth elements Erbium (ER), Praseodymium (Pr) , and Thulium (Tm) has been studied using a pulsed nitrogen laser and germanium detector. The measurements were made with an experimental set up with a system response time of 0.34 micro seconds. A 330 milliwatt nitrogen laser with a wavelength of 3370 angstrums was used to excite transitions of the rare earth elements.

Characterization Of Barium Titanate As An Optical Amplifier, George A. Vogel

Theses and Dissertations

The introduction of two-beam coupling in photorefractive materials has resulted in an extensive amount of research into their use as optical processing/computing elements. This dissertation develops the theoretical equations for two-beam coupling in barium titanate as an optical amplifier. One of the factors which limits the optical gain in photorefractive crystals is the loss of pump beam power to the amplification of parasitic light (beam fanning). This parasitic light is produced by light scattered from the pump beam by imperfections on both the crystal face and within the crystal. Through the analysis of signal and noise amplification as functions of …

Segment Streaming For Efficient Pipelined Televisualization, Fengmin Gong

All Computer Science and Engineering Research

The importance of scientific visualization for both science and engineering endeavors has been well recognized. Televisualization becomes necessary because of the physical distribution of data, computation resources, and users involved in the visualization process. However, televisualization poses a number of challenges to the designers of communication protocols. A pipelined televisualization (PTV) model is proposed for efficient implementation of a class of visualization applications. Central to the proposed research is the development of a segment of streaming IPC (interprocess communication) mechanism in support of efficient pipelining across very high speed internetworks. This requires exploration of special issues arising from extending a …

The Calendar - November 1990, Nova University

The Calendar

No abstract provided.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, November 1990, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

1990scholars And Artists Bibliography, Michael Schwartz Library, Cleveland State University, Friends Of The Michael Schwartz Library

Scholars and Artists Bibliographies

This bibliography was created for the annual Friends of the Michael Schwartz Library Scholars and Artists Reception, recognizing scholarly and creative achievements of Cleveland State University faculty, staff and emeriti

The Calendar - October 1990, Nova University

The Calendar

No abstract provided.

Santa Clara Magazine, Volume 33 Number 1, Fall 1990, Santa Clara University

Santa Clara Magazine

12 - PRIESTS & MARRIAGE The Pope has allowed the ordination of nearly 50 married Episcopal priests since 1980. Some see this as a sign of hope for a married priesthood . By Julie Sly '82

18 - THE POWER OF ONE Because of her own personal tragedy, Mary Beth Cahill Phillips '76 forced the state of California to form Trustline, a registry parents can use to check out a nanny. By Susan Frey

20 - THE ART OF BIOGRAPHY Our natural curiosity about each other tempts us into reading biographies the same way we turn to novels. Is peering …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, October 1990, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Highly Concurrent Logically Synchronous Multicast, Kenneth J. Goldman

All Computer Science and Engineering Research

We define the logically synchronous multicast problem, which imposes a natural and useful structure on message delivery order in an asynchronous system. In this problem, a computation proceeds by a sequence of multicasts, in which a process sends a message to some arbitrary subset of the processes, including itself. A logically synchronously multicast protocol must make it appear to every process as if each multicast occurs simultaneously at all participants of that multicast (sender plus receivers). Furthermore, if a process continually wishes to sends a message, it must eventually be permitted to do so. We present a highly concurrent solution …

A Software Design Tool For Predictable Performance In Real-Time, Data Flow Architectures, Brij Mohan V. Mandala

Electrical & Computer Engineering Theses & Dissertations

A software design tool which aids in the performance evaluation and selection of operating points for an algorithm implemented in ATAMM defined data flow architectures is presented in this thesis. ATAMM (Algorithm To Architecture Mapping Model) is a new graph theoretic model developed by researchers at Old Dominion University and the NASA-Langley Research Center. ATAMM is capable of modeling the execution of large-grained algorithms on distributed data flow architectures. A software tool is required for predicting the performance, determining the resource requirements and for selecting suitable operating points for an ATAMM based system. The ATAMM Design Tool presented in this …

Deep Level Characterization Studies In Gaas, Gordhan R. Barevadia

Electrical & Computer Engineering Theses & Dissertations

The goal of this research was to investigate deep levels in different types of GaAs, a material for high power optically controlled bulk semiconductor switches. For low resistivity semiconductors, such as silicon doped GaAs material (p =0.054 Ω cm), deep level transient spectroscopy (DLTS) was used to characterize deep levels. Three deep levels (EL6, EL3, and EL2) have been detected in this material. For high resistivity semiconductors (p > 10⁴ Ω cm), difficulty of electrical carrier injection and of making a junction does not permit the use of DLTS technique. Therefore, an experimental set-up of the photo-induced current transient spectroscopy …

Pc-Based Ft/Icr System, Shenheng Guan, Patrick R. Jones

Pacific Patents

An apparatus for conducting FT/ICR experimentation and acquiring data using a personal computer and a fast buffer board. The apparatus has the capability of generating an ion excitation signal and acquiring results from the FT/ICR experiment. Those results are then digitized and stored in memory on the fast buffer board. Once the results have been stored in the fast buffer board memory, they are transferred to the personal computer where they can be processed and interpreted by the user.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, September 1990, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Studies In The Hybrid Deterministic Parsing, Stan C. Kwasny, Anne M. Johnstone, Barry L. Kalman

All Computer Science and Engineering Research

This report details research plans to extend work on hybrid deterministic parsing. The approach is hybrid in its combination of symbolic and sub-symbolic (connectionist) approaches. The research is investigating (1) new and more robust architectures for deterministic parsing which are hybrid mixtures of symbolic and sub-symbolic components, (2) combinations of syntax with lexical access and other components of natural language processing in order to determine how the distributed patterns of connectionism may enable better interfaces among these components, and (3) properties of the rules in the rule-based deterministic processing of natural language that make them most suitable for sub-symbolic training. …

Monte Carlo Simulation Of Atmospheric Neutron Transport At High Altitudes Using Mcnp, Donald R. Culp, David L. Monti, James R. Shoemaker, David Wesley, Kirk A. Mathews

AFIT Documents

Neutron transport calculations were performed using the Monte Carol code, MCNP. The transport problem considered has a point source at high altitude (40 km). Since atmospheric density decreases with altitude, two-dimensional effects (cylindrical coordinates) can be important. Results were compared to those obtained with the SMAUG-II computer code, which performs mass-integral scaling of approximate fits to one-dimensional spherical discrete ordinates solutions. These comparisons show the importance of two-dimensional computations. The report discusses practical issues of applying MCNP to this problem, without code modifications and includes example input files for MCNP and for SMAUG-II. Computational modelling of neutron transport in the …

32nd Rocky Mountain Conference

Rocky Mountain Conference on Magnetic Resonance

Program and registration information for the 32nd annual meeting of the Rocky Mountain Conference, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, July 29 - August 3, 1990.

Santa Clara Magazine, Volume 32 Number 4, Summer 1990, Santa Clara University

Santa Clara Magazine

10 - WHAT'S UP WITH COMIC BOOKS? Comic books aren't what they used to be but they continue to charm our children. By Mitch Finley '73

14 - STRESS, ILLNESS, AND PSYCHOTHERAPY The meaning of a stressful situation determines whether it is perceived as a challenge to be overcome or a demoralization. By Jerome D. Frank

18 - A BEELINE TO THE USA "Killer" bees have been winging their way from Brazil since scores of queens escaped a Sao Paolo lab in 1957. By Paul M. McCarthy '46

21 - PROMISE & OPPORTUNITY An economic forecast for the 1990s by …

Research Project Summaries (July 1989-December 1990), Utah Water Research Laboratory

Reports

From every side we hear of new threats to our water supply. Carcinogens, droughts, dam failures, global warming, hazardous wastes, deforestation, overpopulation, liability, and an aging infrastructure become household fears; this list grows longer and more foreboding to the average citizen. Some of these threats are real, while others are imaginary. Some we know how to overcome and others we can find ways to overcome, yet, for some, we are still helpless. The strength of a university lies in its success in stimulating inquisitive minds in critical examination of the problems of the world. People sense hope as experts find …

Grid Generation And Flow Computation About A Martian Entry Vehicle, John Edward Stewart

Mechanical & Aerospace Engineering Theses & Dissertations

A number of vehicles are currently being proposed for a manned mission to Mars. One of these vehicles has a modified blunt-nosed cone configuration. Experimental results have been obtained for this vehicle in 1968. These results show lift-over-drag ratios comparable to those needed for Mars entry. Computations are performed here to verify the earlier results and to further describe the flight characteristics of this vehicle.

An analytical method is used to define the surface of this vehicle. A single-block volume grid is generated around the vehicle using an algebraic Two-Boundary Grid Generation algorithm (TBGG) and transfinite interpolation. Euler solutions are …

Use Of A Generalized Set Of Variables In Fluid Flow Calculations, Pawel Chwalowski

Mechanical & Aerospace Engineering Theses & Dissertations

In fluid flow calculations, a set of generalized field variables is used to replace the more conventional choice of either the conserved variables, or the primitive variables. This generalized set of variables represents an infinite number of possible choices for the specific set of field variables. For algorithms of both the implicit and explicit type, the resulting effect of a change in field variables on a steady-state flow solution is in general relatively small. However, for implicit algorithms, a consistent linearization with respect to the new variables results in dramatic changes in the overall matrix conditioning of the linear systems …

An Artificial Neural Approach To The Decomposition Problem, Chandrashekar L. Masti

Electrical & Computer Engineering Theses & Dissertations

The goal of this thesis is to develop an artificial neural approach toward addressing the intractability involved with the decomposition problem. The search for the lattice of substitution property (s. p.) partitions essential to decompositions is cast into the framework of constraint satisfaction. An artificial neural network is developed to provide solutions by performing optimization of a mathematically derived objective function over the problem space. The issue of transitivity is verified to belong to a class of problems beyond the scope of solvability for conventional quadratic-order constraint satisfaction neural networks. A theorem is stated and proved establishing that third-order correlations …

Visual Speech Training Aid For The Deaf, Subhashri Venkat

Electrical & Computer Engineering Theses & Dissertations

A computer-based vowel articulation training aid has been developed. A "continuous" acoustic-phonetic transformation is performed to map speech parameters to a lower dimensionality display space. There are two possible approaches to this transformation problem. The transformation could be either linear or a combination nonlinear/linear. The nonlinear transformation is performed using a multi-layered feedforward neural network with linear output layers. Speech parameters are extracted either from an analog filter bank arrangement (band energies) or by a digital signal processing procedure (Discrete Cosine Transform Coefficients). The speech parameters obtained from both methods correspond to the spectral envelope of the speech signals. The …

Encoding Phonetic Knowledge For Use In Hidden Markov Models Of Speech Recognition, Danming Qian

Electrical & Computer Engineering Theses & Dissertations

Hidden Markov models (HMM's) have achieved considerable success for isolated-word speaker-independent automatic speech recognition. However, the performance of an HMM algorithm is limited by its inability to discriminate between similar sounding words. The problem arises because all differences between speech patterns are treated as equally important. Thus the algorithm is particularly susceptible to confusions caused by phonetically-irrelevant differences. This thesis presents two types of preprocessing schemes as candidates for improving HMM performance. The aim is to maximize the differences between phonologically-distinct speech sounds while minimizing the effect of variations in phonologically-equivalent speech sounds. The preprocessors presented are a discrete cosine …

Numerical Investigation Of A Non-Newtonian Material Through A Sudden Pipe Expansion, V. G. Masanja

Tanzania Journal of Engineering and Technology (TJET)

A numerical method for solving two dimensional elliptic boundary-value problems of fourth order is used for finding stationary solutions of the equations of motion for a laminar flow through a sudden pipe expansion of an incompressible non-Newtonian fluid with a constitutive equation of the Reiner-Rivlin (R-R) type. Results for the Newtonian fluid, which is a special case, are in excellent agreement with those by previous investigators and they demonstrate the reliability, superiority and accuracy of the method. Results for the non-Newtonian cases could be of value for fixing ideas about visco-elastic behaviour although the R-R fluid allows only inelasticity: this …

Super Linear Learning In Back Propagation Neural Nets, Barry L. Kalman

All Computer Science and Engineering Research

The important feature of this work is the combination of minimizing a function with desirable properties, using the conjugate gradient method (cgm). The method has resulted in significant improvements for both easy and difficult training tasks. Two major problems slow the rate at which large back propagation neural networks (bpnns) can be taught. First is the linear convergence of gradient descent used by modified steepest descent method (msdm). Second is the abundance of saddle points which occur because of the minimization of the sum of squared errors. This work offers a solution to both difficulties. The cgm which is super …

Coke Oven Emissions: A Case Study Of Technology-Based Regulation, John D. Graham, David R. Holtgrave

RISK: Health, Safety & Environment (1990-2002)

After examining and analyzing the experience with coke ovens, the authors conclude that attempts to force technology beyond its demonstrated competence can be both expensive and ineffective in controlling hazards. They also suggest implications for pending proposals to further control air pollution.

Modcad: A Graphic Predetermined Time Standards Software For The Ibm P.C., Raad A. Dawood

Masters Theses

MODCAD is a software program designed to give MODAPTS (MODular Arrangement of Predetermined Time Standards) the capability to generate workplace layouts that can be used in conjunction with the time study analysis. Software packages have been developed for MODAPTS such as MODAPTS Plus and Task Master that allow the user to input the predetermined codes of MODAPTS.

AutoCAD (a computer aided design software) is used to combine MODAPTS codes and workplace layout drawings in a single environment by customizing the standard AutoCAD menus and icons to include the MODAPTS codes and routines. AutoLisp (AutoCAD resident language) is used to write …