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Theses/Dissertations

1993

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Comparison Of Air Traffic Control Candidate Ability With Simulator-Based Training Measures, Lawrence A. Tomaskovic Dec 1993

Comparison Of Air Traffic Control Candidate Ability With Simulator-Based Training Measures, Lawrence A. Tomaskovic

Master's Theses - Daytona Beach

The purpose of this study was to determine if the utilization of an experimental computer-based selection test battery would aid in the prediction of a candidate's performance when using an air traffic control computer-based simulation program. Each candidate completed the selection test battery, and then received air traffic control instruction using the air traffic control simulation program incorporated in the TRACON/Pro™ simulator system. The selection test battery results were correlated with the subsequent simulator scoring results.


The Effect Of Active And Passive Control On Air Traffic Controller Dynamic Memory, Esa M. Rantanen Dec 1993

The Effect Of Active And Passive Control On Air Traffic Controller Dynamic Memory, Esa M. Rantanen

Master's Theses - Daytona Beach

The purpose of this study was to investigate the effect of automated and passive control on air traffic controller dynamic memory. The study consisted of two experiments, each involving a realistic ATC scenario for radar approach control with a mix of arriving and departing traffic. In Experiment I, the subjects performed manual control of the traffic while, in Experiment II, the scenario was highly automated and the subjects were tasked with only monitoring the situation. The dynamic memory performance was measured by interrupting the scenario and having the subjects recall the traffic situation at the moment of simulation interruption. The …


Superplastic Forming System Design, Keith Bain Dec 1993

Superplastic Forming System Design, Keith Bain

Honors Capstone Projects and Theses

No abstract provided.


Application Of Fuzzy Logic For Performance Enhancement Of Drives, Gilberto Costa Sousa Dec 1993

Application Of Fuzzy Logic For Performance Enhancement Of Drives, Gilberto Costa Sousa

Doctoral Dissertations

Fuzzy logic shows enormous potential for advancing power electronics technology. Its application to DC and AC drives control is discussed here.

Initially, a phase-controlled bridge converter DC drive was considered. Analysis of converter performance at continuous and discontinuous conduction modes was first conducted. Fuzzy control was used to linearize the transfer characteristics of the converter in discontinuous conduction mode. It was then extended to current and speed loops, replacing the conventional proportional-integral controllers. The control algorithms were developed in detail, and verified by PC-SIMNON (developed by Lund Institute of Technology Sweden) digital simulation. Significant performance improvement was achieved over conventional …


Evaluation And Implementation Of Asynchronous Adders, Poornima Y. Shankarreddy Dec 1993

Evaluation And Implementation Of Asynchronous Adders, Poornima Y. Shankarreddy

Masters Theses

The need for high speed addition is forcing digital system designers to trade off space. If speed is used as a criterion to judge adders, then the Ripple Carry Adder (RCA) and the Carry Look Ahead Adders (CLAAD) will rank last and first respectively. On the other hand, if space is used, then the order of these two is reversed. The rest of the adders rank between these two. This paper evaluates RCA, CLAAD, and some of the other well documented adders. Both space and speed are used to judge the merits of each of these, and whether or not …


Development Of A Systematic Approach To The Implementation Of A Computer Integrated Manufacturing (Cim) For Small To Medium Sized Companies, G. Steven Trimmer Dec 1993

Development Of A Systematic Approach To The Implementation Of A Computer Integrated Manufacturing (Cim) For Small To Medium Sized Companies, G. Steven Trimmer

Masters Theses

CIM technology is rapidly becoming an essential part of businesses of all types and sizes. The impact on the culture of the enterprise is possibly of even greater complexity. Most existing implementations have been done by large businesses large teams of specialized talent.

The unique scope of this work is to simplify the implementation of CIM for small companies. The basic research derived from the WMU/IBM CIM Management Center, a fully functioning CIM facility that provides hands on experience to students and regional businesses.

The cultural references concerning CIM are derived from reading and personal experiences with industry while setting …


Primary Coolant Flow Characteristics As It Exits The Palisades Reactor, Gregory Alan Baustian Dec 1993

Primary Coolant Flow Characteristics As It Exits The Palisades Reactor, Gregory Alan Baustian

Masters Theses

During fuel cycles 9 and 10 at the Palisades Nuclear Power Plant, new phenomena have been observed using the resistance temperature devices installed in the reactor coolant piping. Oscillations in the temperature readings have been observed leading to the assumptions that there is temperature stratification of the coolant in the reactor hot-legs and that the coolant rotates as it leaves the reactor. In addition, oscillations in the bulk coolant flow within the two hot legs have been postulated. This report outlines work performed using computational fluid dynamics modelling which predict the observed and assumed flow characteristics of the Palisades reactor …


An Empirical Investigation Of Quality And Productivity Management Practices In Manufacturing Firms, Kiran Vuppalapati Dec 1993

An Empirical Investigation Of Quality And Productivity Management Practices In Manufacturing Firms, Kiran Vuppalapati

Masters Theses

A growing number of firms are implementing the concept of Just In Time (JlT) manufacturing and Total Quality Management (TQM). This research examines the impact of these management philosophies in manufacturing firms.

This research identifies a set of critical organizational variables necessary for a successful . implementation and the organizational problems faced during their implementation. The major object is to test the performance of firms implementing both JlT and TQM against firms implementing none of these philosophies. Results show that JIT-TQM firms are more customer focused and have better employee relations than traditional firms. This study also compares the performance …


An Experimental Study Into The Role Of Routing Flexibility In The Justification Of Advanced Manufacturing Systems, Sanjay Pathak Dec 1993

An Experimental Study Into The Role Of Routing Flexibility In The Justification Of Advanced Manufacturing Systems, Sanjay Pathak

Masters Theses

Increased competition in manufacturing has focused attention on advanced technologies. These costly technologies lead to difficulty in purchase justification using traditional methods. New methods quantify attributes relating to the flexibility of advanced systems. One such attribute is routing flexibility.

This thesis presents results of experiments into evaluation of routing flexibility. The performance of conventional dedicated machinery when compared with that of machines having routing flexibility indicates an advantage of flexible machinery. The thesis indicates a procedure for evaluation of different flexibilities and their comparison with conventional machinery in reality.

An empirical formula is developed that helps in quantifying routing flexibility …


Effect Of A Range Ring And Of Intruder Vertical Rate On Pilot Perception Of Separation On A Cockpit Display Of Traffic Information, Paul V. Wassell Dec 1993

Effect Of A Range Ring And Of Intruder Vertical Rate On Pilot Perception Of Separation On A Cockpit Display Of Traffic Information, Paul V. Wassell

Master's Theses - Daytona Beach

This study was conducted to determine the effect of a range ring and intruder vertical rate on pilots’ perception of aircraft separation as viewed on a cockpit display of traffic information. A group of 30 pilots from Embry-Riddle Aeronautical University participated as subjects. SuperCard® Version 1.6 software and a Macintosh IIsi® personal computer were employed to generate the simulation of a cockpit display of traffic information. Each pilot monitored 80 unique scenarios in which they determined, as early as possible, what the vertical miss distance would be when a single intruder passed ownship. The pilots’ decision time and perceived vertical …


Development Of Stereoscopic Particle Tracking Velocimetry For Turbulent Flow Field Diagnostics, Veera P. Rajendran Dec 1993

Development Of Stereoscopic Particle Tracking Velocimetry For Turbulent Flow Field Diagnostics, Veera P. Rajendran

Electronic Theses and Dissertations

Stereoscopic particle tracking velocimetry (SPTV) was used to analyze a turbulent submerged jet of Reynolds number (based on the diameter of the nozzle) 8000. SPTV involves tracking the motion of tracer particles over time in a flow in three dimensions. The first part of this work consisted of developing a stereoscopic particle tracking technique using two high-speed video cameras. This included calibration of the cameras with "known" points, and developing an algorithm to automatically match and track particles. The second part was to apply the same to a submerged water jet in order to measure velocities. The velocities were subsequently …


Satellite Attitude Determination Using Linear Combination Of Models, Martin S. Chin Dec 1993

Satellite Attitude Determination Using Linear Combination Of Models, Martin S. Chin

Theses and Dissertations

In satellite analysis, it is often necessary to determine the attitude of a satellite from a two dimensional image of the satellite. This thesis describes work performed to determine the attitude of a satellite relative to a reference position. The attitude is described in terms of the scaling, rotation and translation of the reference that will result in a pose that can be projected to form the image of interest. The techniques used are based on finding coefficients for the linear combination of basis images and decomposition of a composite transformation matrix. The methods were initially modeled in Mathematica and …


Radar Cross Section Visualization Using Sample Buffer Progressive Refinement Volume Rendering, Alain L. Jones Dec 1993

Radar Cross Section Visualization Using Sample Buffer Progressive Refinement Volume Rendering, Alain L. Jones

Theses and Dissertations

This study developed a prototype for an interactive radar cross section visualization software system. The system, hosted on a Silicon Graphics workstation, is intended to support aircrews, mission planners, aircraft designers, and others who require an understanding of aircraft radar cross section characteristics. The input to the system is a set of radar cross section samples taken at various aspect angles. A pre-processor developed as part of this study transforms the input radar cross section data into a three-dimensional cuberille data volume. This data volume is then visualized using an interactive volume renderer. The interactive volume renderer implements progressive image …


Evaluation Of Moderate Angle Of Attack Roll Of A Dual Engine, Thrust Vectoring Aircraft Using Quantitative Feedback Theory, Kevin E. Boyum Dec 1993

Evaluation Of Moderate Angle Of Attack Roll Of A Dual Engine, Thrust Vectoring Aircraft Using Quantitative Feedback Theory, Kevin E. Boyum

Theses and Dissertations

This thesis develops an innovative approach to the design of a flight control system for performing the large-amplitude velocity vector roll maneuver at high angles of attack AOAs. A six degree of freedom aircraft model is developed from the fundamental nine-state equations of motion using a modified linearization technique. The MIMO multiple-input multiple-output Quantitative Feedback Theory QFT robust control design technique is then used to jointly address the system nonlinearities present in this maneuver and the changes in the system parameters due to changes in flight condition, treating them as structured uncertainty in the design of a three-axis rate-commanded control …


Incorporation Of Carrier Phase Global Positioning System Measurements Into The Navigation Reference System For Improved Performance, Neil P. Hansen Dec 1993

Incorporation Of Carrier Phase Global Positioning System Measurements Into The Navigation Reference System For Improved Performance, Neil P. Hansen

Theses and Dissertations

In order to quantify the performance and accuracy of existing navigation systems, the U.S. Air Force has been using the Completely Integrated Reference Instrumentation System (CIRIS) as a baseline. CIRIS combines information from an inertial navigation unit, a barometric altimeter, and a range/range-rate system of ground transponders to obtain a navigation solution. This research explores the possibilities of enhancing CIRIS by adding measurements obtained from the Global Position System (GPS). Pure pseudorange measurement updates to the CIRIS Extended Kalman Filter form the basis of the Navigation Reference System (NRS). Applying differential corrections to the pseudorange measurements forms the basis of …


Design Of A Flight Controller For An Unmanned Research Vehicle With Control Surface Failures Using Quantitative Feedback Theory, Mark S. Keating Dec 1993

Design Of A Flight Controller For An Unmanned Research Vehicle With Control Surface Failures Using Quantitative Feedback Theory, Mark S. Keating

Theses and Dissertations

This thesis describes the application of the multiple-input multiple- output (MIMO) Quantitative Feedback Theory (QFT) design technique to the design of a digital flight control system for the Lambda Unmanned Research Vehicle (URV). The QFT technique allows the synthesis of a control system which is robust in the presence of structured plant uncertainties. Uncertainties considered in this design are the aircraft's plant variation within the flight envelope and the effects of damage to aircraft control surfaces. Mathematical models of control surface failure effects on aircraft dynamics are derived and used to modify an existing small perturbation model of the Lambda. …


The Afit Multielectrode Array For Neural Recording And Simulation: Design, Testing, And Encapsulation, James R. Reid Jr Dec 1993

The Afit Multielectrode Array For Neural Recording And Simulation: Design, Testing, And Encapsulation, James R. Reid Jr

Theses and Dissertations

A two-dimensional, X-Y addressable, multiplexed array of 256 electrodes (16 x 16) has been fabricated using conventional semiconductor processing techniques. The individual electrodes are 16O microns x 160 microns, approximating the size of the cortical columns; the overall array size is 3910 microns x 3910 microns. The array has been fitted to a chronically implantable package and tested for several days in a simulated neural environment. EEG-like data were collected successfully from individual electrodes in the array. This array improves on a previous design of a 16 electrode (4 x 4) array that was chronically implanted on the cortex of …


Shielded Coil Electrodynamic Propulsion (Scep). A Feasibility Study, Richard J. R. Ladouceur Dec 1993

Shielded Coil Electrodynamic Propulsion (Scep). A Feasibility Study, Richard J. R. Ladouceur

Theses and Dissertations

This study investigated Shielded Coil Electrodynamic Propulsion SCEP. The use of the earths magnetic field as a propulsion source has been previously investigated. It was found that a significant amount of power and long conductors were required. A more compact propulsion concept which requires significantly less power is proposed. This concept relies on the feasibility of significantly reducing the magnetic force induced by the earths magnetic field on selected segments of a coil. An experiment design to support the theoretical findings was conducted. The experiment results support the theoretical model.


Objective Image Quality Metrics: Applications For Partially Compensated Images Of Space Objects, David J. Lee Dec 1993

Objective Image Quality Metrics: Applications For Partially Compensated Images Of Space Objects, David J. Lee

Theses and Dissertations

Digital image reconstruction tasks currently require human intervention for a subjective evaluation of image quality. A method for unsupervised measurement of digital image quality is desired. This research investigated various parameters metrics that can be automatically extracted from a digital image and tested how well they correlated with image quality. Specifically, images of orbiting satellites captured by a partially compensated adaptive optics telescope were dealt with. Two different types of quantities were investigated 1) Fourier spectral parameters, based on the spatial- frequency sensitivities of the HVS; and 2) Histogram shape parameters i.e image statistical moments giving quantitative insight into the …


An Evaluation Of The Software Engineering Institute's Capability Maturity Model As A Framework For Software Process Improvement At Three Air Logistics Centers, Brian G. Hermann, Raymond J. Lewis Jr. Dec 1993

An Evaluation Of The Software Engineering Institute's Capability Maturity Model As A Framework For Software Process Improvement At Three Air Logistics Centers, Brian G. Hermann, Raymond J. Lewis Jr.

Theses and Dissertations

This research sought to determine whether a relationship exists between the maturity level of the software process, as determined by the Software Engineering Institutes Capability Maturity Model SEI CMM, and the actual success of particular software projects at three US Air Force Air Logistics Centers. Project success is defined in terms of cost, schedule, and quality criteria. In addition, each organizations acceptance of the SEI assessment as well as its effectiveness in setting up follow-on process improvement programs were evaluated. Finally, the process improvement programs were reviewed individually inasmuch as these programs are the mechanisms for achieving improved quality, lower …


Optimal Control Design Advantages Utilizing Two-Degree-Of-Freedom Controllers, Michael J. Stephens Dec 1993

Optimal Control Design Advantages Utilizing Two-Degree-Of-Freedom Controllers, Michael J. Stephens

Theses and Dissertations

The purpose of this study was to investigate and describe the differences between a one-degree-of-freedom (1-DOF) controller, in which a controller is placed in a single location in the control loop, and a two-degree- of-freedom (2-DOF) controller, in which two separate controllers are designed -- one in the feedback loop and the other as a prefilter in the forward loop. The approach involved summarizing the major rules governing loop shaping for performance and robustness in the 1-DOF case and then extending the concepts to the 2-DOF case. H2 optimization was utilized to perform several types of SISO examples and …


Evaluation Of A Concentration Probe For Application In A Supersonic Flow Field, John S. Alsup Dec 1993

Evaluation Of A Concentration Probe For Application In A Supersonic Flow Field, John S. Alsup

Theses and Dissertations

Aspirating, concentration probes are used to measure binary gas concentrations in a supersonic flow. In the past, a tank discharge method has been used to calibrate concentration probes. An alternate calibration method has been developed and tested on a probe in a steady, subsonic/sonic flow. This study evaluated the calibration and performance of a concentration probe in a steady, supersonic flow over a range of mixture ratios of air and helium. The results of this study and a comparison of the two calibration methods are presented.


Using Discovery-Based Learning To Prove The Behavior Of An Autonomous Agent, David N. Mezera Dec 1993

Using Discovery-Based Learning To Prove The Behavior Of An Autonomous Agent, David N. Mezera

Theses and Dissertations

Computer-generated autonomous agents in simulation often behave predictably and unrealistically. These characteristics make them easy to spot and exploit by human participants in the simulation, when we would prefer the behavior of the agent to be indistinguishable from human behavior. An improvement in behavior might be possible by enlarging the library of responses, giving the agent a richer assortment of tactics to employ during a combat scenario. Machine learning offers an exciting alternative to constructing additional responses by hand by instead allowing the system to improve its own performance with experience. This thesis presents NOSTRUM, a discovery-based learning DBL system …


A Study Of Two Dimensional Tapered Periodic Edge Treatments To Reduce Wideband Edge Diffraction, Russell A. Burleson Dec 1993

A Study Of Two Dimensional Tapered Periodic Edge Treatments To Reduce Wideband Edge Diffraction, Russell A. Burleson

Theses and Dissertations

This is a brief summary of a study to reduce diffraction from an infinite two dimensional edge using tapered periodic surfaces. The concept is to use the impedance characteristics of a periodic surface to create a tapered impedance much like a tapered resistance commonly used for diffraction reduction. This approach has several advantages over. tapered resistive treatments to include ease of fabrication, better engineering control of the impedance and negligible loss absorbed by the ta per. In this study, four periodic tapers were design, built and tested. These tapers were also modeled using a variety of numerical techniques. The results …


Human Visual System Enhancement Of Reconstructed Satellite Images, James E. Treleaven Dec 1993

Human Visual System Enhancement Of Reconstructed Satellite Images, James E. Treleaven

Theses and Dissertations

This research investigated the enhancement of satellite images. The goal was to develop and test a suite of image enhancement software routines to improve the quality of reconstructed images for the human visual system. The primary focus was to enhance satellite features. Enhancement was accomplished in both the spatial domain and the frequency domain. In the spatial domain, routines were developed to enhance image contrast and edges. In the frequency domain, a routine was developed using research into the human visual system. The transfer function of the human visual system was used to develop a filter for frequency domain enhancement. …


Modeling Of Algal Productivity And Diel Oxygen Profiles In The Partitioned Aquaculture System, Caye M. Drapcho Dec 1993

Modeling Of Algal Productivity And Diel Oxygen Profiles In The Partitioned Aquaculture System, Caye M. Drapcho

All Dissertations

Fish production in pond culture systems is often limited by the dissolved oxygen (DO) concentration. Algal biomass and productivity, which greatly impact the DO concentration, are difficult to control in traditional pond systems. The Partitioned Aquaculture System (PAS) was designed to increase fish production by managing algal productivity and DO through control of algal cell retention time, water depth, and mixing. The objectives of this study were 1) to determine impact of culture conditions on algal productivity, 2) develop a model of algal productivity and diel DO levels, and 3) to predict the maximum fish production attainable with the PAS. …


An Analysis Of Fm Jamming And Noise Quality Measures, Timothy N. Taylor Dec 1993

An Analysis Of Fm Jamming And Noise Quality Measures, Timothy N. Taylor

Theses and Dissertations

This thesis provides a description of FM-by-noise jamming, both at RF and at the output of the radar receiver, in terms of spectra, time-domain waveforms, and univariate probability density of amplitude. Particular emphasis is given to the case where the peak frequency deviation of the FM modulator is sufficiently small that Woodward's Theorem does not provide a good approximation of the RF spectrum. Additionally, noise quality measures which have been used to measure noise quality of radar jammers are considered theoretically and experimentally, and it is concluded that a noise measure which incorporates both a spectral measure and a probability …


Creation Of Prototype Aircrew Protection Equipment Based On Face Anthropometry, Martin E. Piccus, Gary A. Smith, Brian K. Standley, Tami L. Volk, Linda B. Wildes Dec 1993

Creation Of Prototype Aircrew Protection Equipment Based On Face Anthropometry, Martin E. Piccus, Gary A. Smith, Brian K. Standley, Tami L. Volk, Linda B. Wildes

Theses and Dissertations

The objective of this research is to develop a process which will analyze and group human faces, concentrating on the oxygen mask seal area, into a minimum number of generic yet distinct face types. The shape and size, or form, of the face is described by bending energies. This bending energy provides the features for the grouping of similar face types, while distinguishing representatives for each cluster. The face tariffs are the percentage of faces grouped under a representative face. The representative faces are then transformed Into three-dimensional solids using computer-aided design. A rapid prototype creates the solids or plugs …


Filtering, Coding, And Compression With Malvar Wavelets, Stephen R. Hall Dec 1993

Filtering, Coding, And Compression With Malvar Wavelets, Stephen R. Hall

Theses and Dissertations

This thesis develops and evaluates a number of new concepts and tools for the analysis of signals using Malvar wavelets lapped orthogonal transforms . Windowing, often employed as a spectral estimation technique, can result in irreparable distortions in the transformed signal. By utilizing the Malvar wavelet, any signal distortion resulting from the transformation can be eliminated or cancelled during reconstruction. This is accomplished by placing conditions on the window and the basis function and then incorporating the window into the orthonormal representation. Paradigms for both a complex-valued and a real-valued Malvar wavelet are summarized. I-lie algorithms for the wavelets were …


A Methodology To Assess The Impact Of The Global Positioning System On Air Combat Outcomes, Stephen F. Sovaiko Dec 1993

A Methodology To Assess The Impact Of The Global Positioning System On Air Combat Outcomes, Stephen F. Sovaiko

Theses and Dissertations

The Air Force has a requirement to quantify the force enhancement effects of military space systems, but no methodology currently exists for the measurement of their contribution to air combat outcome. This research examines the Global Positioning System GPS and models its influence on air-to-ground combat. The decision analysis technique of influence diagrams is used to identify the effects of GPS launch decisions and constellation size on the navigation accuracy available to air combatants. The effect of accuracy variations on combat outcome is shown by using a value tree to identify the affected campaign Measures of Effectiveness. The study reveals …