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Model-Based 3-D Recognition System Using Gabor Features And Neural Networks, Phung D. Le
Model-Based 3-D Recognition System Using Gabor Features And Neural Networks, Phung D. Le
Theses and Dissertations
A different approach to pattern recognition was attempted using Gabor features, artificial neural nets, and an image generator. The Gabor features and artificial neural nets are sound biological-based, and the image generator provides complete access to any view of an object. This thesis tested the idea that their integration could form a robust 3-D recognition system. The results of the research showed that the Gabor features together with a neural net were used successfully in classifying objects regardless of their positions, out-of- plane rotations, and to a lesser extent in-plane rotations. The Gabor features were obtained by correlating the image …
A Compact Optical Associative Memory Using Dynamic Holographic Storage Media And Photorefractive Gain And Attenuation Elements, Thomas J. Burns
A Compact Optical Associative Memory Using Dynamic Holographic Storage Media And Photorefractive Gain And Attenuation Elements, Thomas J. Burns
Theses and Dissertations
This research effort implemented a compact optical associative memory architecture consisting of a Fabry-Perot Confocal Resonator (FPCR) optical processing environment, two dynamically reprogrammable Lithium Niobate volume holograms, and Barium Titanate gain and attenuation elements. The reduced physical dimensions of the compact optical processing environment make it more adaptable to military applications than previous associative memory designs. The FPCR employs Mangin mirrors designed to reduce spherical aberrations in off-axis rays. The orientation of the gain element's grating vector angle and the model used to predict the profile of the attenuation element were unique to this research effort. The object stored in …
Using Error Detection And Correction Coding For A Turbulent Atmospheric Optical Communications Link, Mark A. Cloutier
Using Error Detection And Correction Coding For A Turbulent Atmospheric Optical Communications Link, Mark A. Cloutier
Theses and Dissertations
Probability of bit error (Pb) performance for a turbulent, atmospheric, optical, communications link with convolutional error detection and correction coding was investigated. The codes investigated were all rate 1/2 codes with constraint lengths ranging from 3 to 7. It was assumed that the coded data stream was sufficiently interleaved so that the turbulent channel could be considered memoryless. A theoretical bound on Pb, given by Viterbi for a memoryless channel, was used to plot curves of Pb versus the signal intensity of last transmitter. These curves were plotted for three different levels of atmospheric turbulence and three …
A Biologically-Inspired Neural Network Architecture For Image Processing, Laurence E. Lazofson
A Biologically-Inspired Neural Network Architecture For Image Processing, Laurence E. Lazofson
Theses and Dissertations
This thesis project included a literature survey of biological and artificial neural network research followed by development and testing of high- order and image recognition hierarchical neural network algorithms. Following training, performance testing of second-order and third-order networks yielded maximum accuracies comparable to those achieved by multilayer perceptron classifiers operating on test data sets. Several versions of an image classification algorithm were tested for learning performance using pixel data from forward-looking infrared (FLIR) images of tanks, trucks, target boards, and clutter. Employing the biologically-motivated Lambertization and contrast normalization of pixel windows, correlations with multiple Gabor function wavelets, and a 'phase …
Optical Image Segmentation Using Wavelet Filtering Techniques, Christopher P. Veronin
Optical Image Segmentation Using Wavelet Filtering Techniques, Christopher P. Veronin
Theses and Dissertations
This research effort successfully implemented an automatic, optically based image segmentation scheme for locating potential targets in a cluttered FLIR image. Such a design is critical to achieve real-time segmentation and classification for machine vision applications. The segmentation scheme used in this research was based on texture discrimination and employs orientation specific, bandpass spatial filters as its main component. The orientation specific, bandpass spatial filters designed during this research include symmetrically located circular apertures implemented on heavy, black aluminum foil; cosine and sine Gabor filters implemented with detour-phase computer generated holography photoreduced onto glass slides; and symmetrically located circular apertures …
Energy Transfer In Singlet Oxygen And Bromine Monofluoride, Barrett F. Lowe
Energy Transfer In Singlet Oxygen And Bromine Monofluoride, Barrett F. Lowe
Theses and Dissertations
The interhalogen molecule, bromine monofluoride (BrF), is currently under study as a potential candidate for a visible chemical laser medium. Previous studies have shown a strong emission from BrF(B3π(O+)) in the presence of singlet oxygen. While singlet oxygen will pump BrF(X) to BrF(B), the exact mechanism is not known. Chemiluminescence observed from BrF(B) excited by oxygen in a gas flowtube was used to study the energy transfer mechanism. The objective of this research was fourfold. First, the pumping process was identified as a 3- Body Mechanism. Second, the observed vibrational distribution clearly showed the population of …
An Optically Pumped Molecular Bromine Laser, Jon W. Morrison
An Optically Pumped Molecular Bromine Laser, Jon W. Morrison
Theses and Dissertations
An optically pumped molecular bromine laser was studied to investigate the quenching kinetics state of Br2. This included characterization of the pressure dependence of the laser output power. The approach was to excite molecular bromine in a sealed cell with a Nd:YAG pumped dye laser. Unresolved side fluorescence and amplified stimulated emission (ASE) spectra were recorded. ASE offered the advantage of a simpler optical system with no externally induced wavelength dependencies. Stimulated emission as a signal monitor offered greater resolution than side fluorescence spectra and facilitated spectroscopic assignment.
Operating Characteristics Of Xenon Gas Discharges, Michael E. Ruark
Operating Characteristics Of Xenon Gas Discharges, Michael E. Ruark
Theses and Dissertations
The voltage-current and spectral line intensity-current characteristics were measured for four Xenon gas discharges. The four discharge configurations were made up of two tubes, each examined at pressures of 1 and 10 Torr. The first tube was a hot filament tube with a 1 cm radius, and the second a cold cathode type tube of radius .3 cm. Intensity dependence upon current was primarily linear in all cases with some important deviations. The hot filament tube at 10 Torr showed a large decrease in intensity between 4 and 6 mA in the 8409 angstrom line. This is thought to be …
Determination Of The Optical Properties Of Organic Thin Films By Spectroscopic Ellipsometry, Mark L. Sward
Determination Of The Optical Properties Of Organic Thin Films By Spectroscopic Ellipsometry, Mark L. Sward
Theses and Dissertations
This thesis demonstrated the feasibility of determining the optical properties of organic and polymer thin films through the use of Spectroscopic Ellipsometry (SE). Tan Psi and cos Delta data from 300-800 nanometers (NM) were taken with a Rudolph Research s2000 spectroscopic ellipsometer four samples: indium tin oxide (ITO) coated glass; five layer poly-benzyl-L glutamate (PBLG) organic film on ITO coated glass; eight layer PBLG film on ITO coated glass; and a thiophene polymer film on a microscope slide. The data sets were fit to a choice of four computer models based on a paper written by Dwight Berreman in 1972. …
Multidisciplinary Modeling And Design Of A Space Structure, Brian K. Cassiday, Lawrence L. Gatchet, John T. Tester, Stephen O. Gaines Ii, Mario N. Moya
Multidisciplinary Modeling And Design Of A Space Structure, Brian K. Cassiday, Lawrence L. Gatchet, John T. Tester, Stephen O. Gaines Ii, Mario N. Moya
Theses and Dissertations
A method is needed to simultaneously integrate several engineering disciplines into one complete model to determine the performance of the system as a whole during the design development. System engineering methodologies are particularly suited to this problem. These methods provide a structured approach to problem formulation and system parameter identification. Bond graphs are also well suited as bond graphs model power flow and energy relationships within subsystems, a characteristic inherent to all dynamic systems. The intent of this research was to demonstrate the use of concurrent engineering theory to systematically model a large flexible space structure involving several engineering disciplines. …
An Aluminum Salvage Station For The External Tank (Asset), James N. Haislip Jr., William C. Raynes Jr., David L. Van Matte, Roger E. Linscott, Michael A. Skinner
An Aluminum Salvage Station For The External Tank (Asset), James N. Haislip Jr., William C. Raynes Jr., David L. Van Matte, Roger E. Linscott, Michael A. Skinner
Theses and Dissertations
The external tank is currently the only non-reusable portion of the National Space Transportation System. The tank has 98% of the energy required to be placed in orbit at the point it is jettisoned. The purpose of this study is to develop techniques which would transform this throw-away item into a source of construction material at low earth orbit. A simulation is developed to verify the reduction timelines and peak power requirements for manual and automated reduction. The required tools to accomplish the tasks of initial cutting, product transport, spray on foam insulation removal, and product storage are developed. A …
A Procedure For Performance Assessment Of Drugs Hypothesized To Be Effective In Controlling Motion Sickness, Zainab N. Ahmed
A Procedure For Performance Assessment Of Drugs Hypothesized To Be Effective In Controlling Motion Sickness, Zainab N. Ahmed
Theses and Dissertations
The Air Force Institute of Technology (AFIT) is conducting research into the effectiveness of certain drugs for controlling motion sickness. If the drugs are found to be useful, they must still be proven to have no harmful effects on the operator's performance abilities. There are many methods for assessing performance effects of drugs but very little standardization exists. The Unified Tri-Services Cognitive Performance Assessment Battery (UTC-PAB) is a performance assessment method designed to be used by all military branches. This will encourage standardization of drug testing, exchange of data, and comparability of methods. Five tests were chosen from the UTC-PAB …
Model-Based Reasoning In The Detection Of Satellite Anomalies, Ralph W. Dries
Model-Based Reasoning In The Detection Of Satellite Anomalies, Ralph W. Dries
Theses and Dissertations
Automatic fault detection and recovery would be a mandatory requirement for a satellite where some degree of autonomy is required. This thesis reviews some AI techniques used for the detection of satellite anomalies, and concludes that the model-based reasoning paradigm is best suited for automated on-board fault detection because it can cope with situations not necessarily programmed into the knowledge base. Using the Scheme language and its SCOOPS object oriented extension, development of software is described that models the pitch control channel in the attitude and velocity control subsystem of a typical geo-stationary communications satellite. This model is used by …
An Analysis Of The Effects Of Phenytoin In Treating Motion Sickness And The Effects Of Motion Sickness On The Human Electroencephalogram, Todd M. Banducci
An Analysis Of The Effects Of Phenytoin In Treating Motion Sickness And The Effects Of Motion Sickness On The Human Electroencephalogram, Todd M. Banducci
Theses and Dissertations
This research had two goals: to continue the ongoing research at AFIT to determine the efficacy of the anticonvulsant drug phenytoin in combating the onset and progression of motion sickness; and to note whether or not there is a discernable similarity in the brains of the test subjects to indicate a common point of origin (epicenter) and propagation pattern of the effects of motion sickness in the brain. Eight male DOD personnel were used as subjects to complete twelve trials. Four subjects completed the phenytoin verses placebo double-blind crossover experiment. These four subjects experienced a 99% mean increase in their …
A Correlation And Forecasting Analysis On Lost Satellites, Kenneth R. Norton
A Correlation And Forecasting Analysis On Lost Satellites, Kenneth R. Norton
Theses and Dissertations
The relationship between the size of the United States Air Force Space Command's lost satellite lists and thirteen other variables is investigated. The thirteen variables contain the Space Surveillance Center crew's effort to work the lost list, solar activity, geomagnetic field strength, and the number of observations received each day from seven space track sensors. To identify the relationship of cause and effect between the lost lists and the thirteen variables, simple and multiple linear regressions are used on a data set that begins on 1 January 1988 and ends on 31 December 1988. Multiple linear regression and basic time-series …
A Limited Antiballistic Missile System, Jay H. Payne
A Limited Antiballistic Missile System, Jay H. Payne
Theses and Dissertations
This investigation examines the possibilities of deploying a limited ABM system to counter launches from Third World regions. It is a systems analysis of the entire concept, with the objective of determining if the existing missile warning network could detect launches from Third World regions, and if an ABM component could be integrated into the network. A computer model was used to determine if launches would be detected, and examine the warning time provided. Based on sample data, the warning network appears capable of detecting Third World launches. Warning times provided by the network appears to provide adequate time to …
Improving Reliability In A Stochastic Communication Network, William L. Gaught
Improving Reliability In A Stochastic Communication Network, William L. Gaught
Theses and Dissertations
This research investigated the behavior of increasing the reliability of components in stochastic communication networks. A stochastic communication network is one in which the components, links and nodes, are not 100 percent reliable. In addition the reliability value, each component also has a capacity value that limits the flow through the component. The throughput in a stochastic communication network can be improved by increasing the capacity or the reliability of the individual components. A set of linear and nonlinear models was developed to determine the best investment strategy for increasing the reliability of individual components. Once the models were developed, …
A Computer Model Of A Co2 Oscillator-Amplifier System, William F. Anderson
A Computer Model Of A Co2 Oscillator-Amplifier System, William F. Anderson
Theses and Dissertations
An existing CO2 laser amplifier simulation model developed for use on IBM-compatible personal computers has been improved through the redesign and addition of supplemental procedures from several models. The models and selected procedures which form the basis of the improved model are described. One procedure calculates the pumping rates of CO2 and N2 through calculation of the Boltzmann equation. Another procedure calculates the average vibrational temperatures of C2's vibrational modes. A third procedure replaces the Runge- Kutta integrator used in the original model with a faster, more accurate Adams- Bashforth-Moulton predictor-corrector integrator.
Debris Production In Hypervelocity Impact Asat Engagements, Stephen K. Remillard
Debris Production In Hypervelocity Impact Asat Engagements, Stephen K. Remillard
Theses and Dissertations
This study reviews laboratory experiments on hypervelocity impacts and applies the results from those experiments to predict the mass of debris produced, the number of particles, and the size distribution of the debris particles produced in an ASAT engagement using kinetic energy weapons. The three possible types of hypervelocity collisions are discussed and parameters are provided that will help predict what type of collisions will occur between a given projectile and a target satellite. Once the collision type is determined, various equations are supplied which can be used to calculate debris mass, etc. Next, a notional attack between a miniature …
Measuring The Effectiveness Of Space: Satellite Weather Systems, Steven T. Wilson
Measuring The Effectiveness Of Space: Satellite Weather Systems, Steven T. Wilson
Theses and Dissertations
Using concepts from multivariate utility theory, basic orbital mechanics, and information regarding operational and planned meteorological satellites, this thesis develops a meaningful MOE to support high-level decision making regarding the allocation, acquisition, and operational deployment of space meteorological satellite (METSAT) assets. Satellite meteorological systems were chosen because of the ready availability of pertinent unclassified data. However, the methodology presented may be applied to any type of space system.
Development Of An Image Registration Technique For Polar-Orbiting Satellites, Jerry L. Mehlberg
Development Of An Image Registration Technique For Polar-Orbiting Satellites, Jerry L. Mehlberg
Theses and Dissertations
In this thesis, a means to perform spatial registration (gridding) of meteorological satellite data is developed. It is applicable to Automatic Picture Transmission (APT) data from the TIROS-N series polar-orbiting satellites operated by the National Oceanic and Atmospheric Administration (NOAA). This technique does not require the use of ground control points. Registration is accomplished using an advanced orbital model to precisely compute the satellite's location based on NORAD two-line element sets and the time of the image. This technique is examined for accuracy and sensitivity to errors in the element set and satellite attitude control. This study involves over 70 …
Analysis Of Space Radiation Effects In Gallium Arsenide And Cadmium Selenide Semiconductor Samples Using Luminescence Spectroscopic Techniques, Brad Lee Shaffer
Analysis Of Space Radiation Effects In Gallium Arsenide And Cadmium Selenide Semiconductor Samples Using Luminescence Spectroscopic Techniques, Brad Lee Shaffer
Theses and Dissertations
Analysis of space radiation effects in gallium arsenide and cadmium selenide semiconductor samples using luminescence spectroscopic techniques. The M0006 semiconductor samples were placed into a 28.5 degree inclination, 480 km altitude, near-circular orbit aboard the Long Duration Exposure Facility satellite and exposed to direct space environment for a period of 11 months, and were shielded by 0.313 inches of aluminum for another 58 months. The samples were examined for changes using cathodoluminescence and photoluminescence in various wavelength regions from 0.5 to 1.8 microns. Samples were cooled to approximately 10 degrees Kelvin in a vacuum of 10-8.
Proposed Design Of A Tactical Reconnaissance Satellite System, John D. T. Severance
Proposed Design Of A Tactical Reconnaissance Satellite System, John D. T. Severance
Theses and Dissertations
Tactical reconnaissance is a much needed wartime asset, yet with the deactivation of all active-duty RF-4C squadrons world-wide there appears to be a gap in this country's war-fighting capability. This study proposes a system which utilizes a constellation of small tactical satellites and mobile ground receiving stations that can fulfill the tactical reconnaissance mission. A literature review gives background information on resolution variables, the RF-4C, space reconnaissance, and sensing technologies. After defining system requirements and constraints, a basic system concept is determined. Three alternative systems, separated mostly by threat scenario, technology, and cost, are evaluated using Athey's Systematic Systems Approach. …
Application Of Influence Diagrams In Identifying Soviet Satellite Missions, Cary C. Chun
Application Of Influence Diagrams In Identifying Soviet Satellite Missions, Cary C. Chun
Theses and Dissertations
This thesis investigates the feasibility of applying influence diagrams to capture expert knowledge and incorporate decision theory to construct a Soviet satellite mission prediction model. Before a Soviet launch occurs, formulations of the model's prior probability distribution allows the input of expert knowledge and any available information. As the predictive variables of the model become known, the information is used to successively refine the estimate of the probable mission, thereby, reducing the uncertainty in the model. Discretizing is used to approximate continuous variables as discrete variables which successfully allows the combination of both variable types in a single influence diagram …
A Comparison Of Human-Computer Interfaces In Air Force Organizations, Michael G. Morris
A Comparison Of Human-Computer Interfaces In Air Force Organizations, Michael G. Morris
Theses and Dissertations
This thesis investigated differences in organizational efficiency and effectiveness for users of graphical user interfaces and text-based interfaces on personal computers in Air Forces offices. Areas of interest included amount of time required to learn the basic system, amount of time required to learn new application, users' ratings of user-friendliness, users' perceptions of the extent that their system help them perform in their job, the number of software packages used on the job by users of each system, user satisfaction, responsible authorities' ratings of quality of output, and the relationship between user job experience level and interface used on the …
A Study Of The Air Force's Current Method Of Training Individuals To Use Contractor Developed Software In Information Management And The Perceived Effectiveness Of Training, Bruce F. Harmon
Theses and Dissertations
The purpose of this research was to determine if the Air Force's current method of training untrained individuals to use contractor developed automated information management software is producing the desired levels of productivity and the effectiveness of the training. The study found that greater emphasis must be placed on developing and supporting the use of a standardized training program for the managers and users of automated information management software. Due to the lack of quality training, the majority of survey respondents felt they could perform their jobs more efficiently and be more productive if they had some/more training. The study …
An Assessment Of The Factors In Office Automation Systems Affecting Air Force Middle Managers And Clerical Workers In The Information Management Career Field, Loy C. Cook
Theses and Dissertations
The purpose of this thesis was to investigate the attitudes and opinions of personnel affected by two office automation systems. Reprographics Automated Management System (RAMS) and Records Information Management System (RIMS). Eight investigative questions were posed: (1) How receptive were information management personnel to the office automation systems (RAMS and RIMS)? (2) Were information management personnel's perception different now from the period prior to installation of the office automation systems? (3) What is the frequency of use for each office automation system? (4) What major factors impede these office automation projects (RAMS/RIMS)? (5) What major factors facilitate these office automation …
An Evaluation Of The Educational Background And Knowledge Base Of Air Force Information Management Officers, Summer E. Scott
An Evaluation Of The Educational Background And Knowledge Base Of Air Force Information Management Officers, Summer E. Scott
Theses and Dissertations
This study compares the educational background and knowledge base recommended for Information Management professionals to that currently possessed by Air Force Information Management (IM) officers. The literature review revealed that information managers should have an educational background that provides them with knowledge in the areas of people, computers, systems, models, organization, and society. Statistics made available through the Air Force Manpower and Personnel Center (AFMPC) indicated that only 2.1% of all 70XX officers have a complete information resource management background, and only 7% have a technical or computer-related background.
Investigating The Application Of The Theory Of Constraints To The Scheduling Environment Of The Iaf's Depots, Lewis S. Trigger
Investigating The Application Of The Theory Of Constraints To The Scheduling Environment Of The Iaf's Depots, Lewis S. Trigger
Theses and Dissertations
This research investigated the application and merits of the Theory of Constraints (TOC) to the scheduling environment of the Israeli Air Force's (IAF) maintenance depots. TOC was extensively reviewed including an elaboration of the TOC paradigm and the scheduling procedures developed for a commercial manufacturing setting. Background information was also presented on the IAF depots and traditional scheduling rules. An experiment was designed and conducted that simulated a simplified version of the process flow of the armaments depot. the simulation compared the terms of lower inventory and makespan. The experiment did not conclusively show any difference in standard throughput hours …
Nato Armaments Cooperation: The Case Of The European Fighter Aircraft, Carlos J. Sancho Gonzalez
Nato Armaments Cooperation: The Case Of The European Fighter Aircraft, Carlos J. Sancho Gonzalez
Theses and Dissertations
Difficulties faced by cooperative acquisition programs are identified as the inability to agree on common requirements and the existence of economic or political interests of the partner nations which conflict with or impinge on the program. These are the causes of failure of many of the past cooperative projects undertaken by NATO countries for the purpose of standardization. The study investigated the European Fighter Aircraft (EFA) program in order to find if the same holds true for the EFA and the impact that those difficulties had in the program. The EFA has been subject to the same problems. All the …