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Air Force Institute of Technology

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Ins Aiding By Tracking An Unknown Ground Object, Mursy Polat Mar 2002

Ins Aiding By Tracking An Unknown Ground Object, Mursy Polat

Theses and Dissertations

The reduction of the navigation error in an inertial navigation system by optically tracking a ground object is investigated. Multiple observations of the ground object are used. The location of the ground object is assumed unknown. A careful analysis of the measurement situation at hand reveals that by optically tracking an unknown ground object using passive, bearings-only measurements, the aircraft's angle of attack and sideslip angle can be measured. Thus, two new independent measurement equations featuring the aircraft's angular navigation variables are obtained. Hence, by optically tracking over time an unknown ground object, inertial navigation system aiding is in fact …

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Development Of A Tm:Ho:Ylf-Laser-Pumped Orientation-Patterned Gallium Arsenide Optical Parametric Oscillator, Michael D. Harm Mar 2002

Development Of A Tm:Ho:Ylf-Laser-Pumped Orientation-Patterned Gallium Arsenide Optical Parametric Oscillator, Michael D. Harm

Theses and Dissertations

Coherent optical sources in the mid-infrared region (mid-IR) are important fundamental tools for infrared countermeasures and battlefield remote sensing. Nonlinear optical effects can be applied to convert existing near-IR laser sources to radiate in the mid-IR. This research focused on achieving such a conversion with a quasi-phase matched optical parametric oscillators using orientation-patterned gallium arsenide (OPGaAs), a material that can be quasi-phased matched by periodically reversing the crystal structure during the epitaxial growth process. Although non-linear optical conversion was not ultimately achieved during this research, many valuable lessons were learned from working with this material. This thesis reviews the theory …

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Categorizing Network Attacks Using Pattern Classification Algorithms, George E. Noel Iii Mar 2002

Categorizing Network Attacks Using Pattern Classification Algorithms, George E. Noel Iii

Theses and Dissertations

The United States Air Force relies heavily on computer networks for many day-to-day activities. Many of these networks are affected by various types of attacks that can be launched from anywhere on the globe. The rising prominence of organizations such as the AFCERT and the MAJCOM NOSCs is evidence of an increasing realization among the Air Force leadership that protecting our computer networks is vitally important. A critical requirement for protecting our networks is the ability to detect attacks and intrusion attempts. This research is an effort to refine a portion of an AFIT-developed intrusion detection system known as the …

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Estimation Of Atmospheric Precipitable Water Using The Global Positioning System, David A. Garay Mar 2002

Estimation Of Atmospheric Precipitable Water Using The Global Positioning System, David A. Garay

Theses and Dissertations

This research focuses on using the Global Positioning System (GPS) for atmospheric precipitable water (PW) estimation. Water vapor, measured in terms of PW, plays a crucial role in atmospheric processes and short-term weather forecasting. Traditional methodologies for measuring atmospheric water vapor distributions have known inadequacies, resulting in the motivation to gain good water vapor characterization via GPS. The ability to accurately forecast cloud formation and other weather phenomenon is critical, especially in the case of military operations. Using a network of GPS receivers, it is possible to estimate precipitable water throughout the network region with better accuracy than traditional methods …

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Estimating The Operating And Support Cost Difference Among Tuaf C-130, C-130b And Usaf C-130j Aircraft, Kubilay Kosucu Mar 2002

Estimating The Operating And Support Cost Difference Among Tuaf C-130, C-130b And Usaf C-130j Aircraft, Kubilay Kosucu

Theses and Dissertations

In an era of decreasing defense budgets in Korea, the Korean Air Force Transportation Department has suffered from an insufficient vehicles procurement budget, resulting in fewer vehicles of increasing age, as well as decreasing military morale. For these reasons, the Korean Air Force Transportation Department needs a breakthrough to retain the transportation ability to support the field of operation in an effective and economic way. However, the Korea Air Force Transportation Department has only one method for procuring general-purpose vehicles, which is purchasing. Thus, the comparative analysis of leasing versus buying vehicle study started from the recognition of this situation …

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Designing An Algorithm To Predict The Intensity Of The Severe Weather Season, Hugh J. Freestrom Mar 2002

Designing An Algorithm To Predict The Intensity Of The Severe Weather Season, Hugh J. Freestrom

Theses and Dissertations

The Mesoscale Model 5th Generation (MM5) is used for operational support to Air Force missions in the Alaskan Theater. The 11th Operational Weather squadron has identified problems with the MM5 producing excessively warm surface temperatures. The Polar MM5 (PMM5), developed by the Byrd Polar Research Center for high latitude ice sheets, is tested over the Alaskan domains used by the Air Force Weather Agency to determine the utility in replacing the MM5 with the PMM5. The verification of surface temperature, pressure and wind as well as upper-air temperature, geopotential height, and relative humidity of 27-hour PMM5 forecasts are compared to …

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Verification Of Mm5 Cloud Microphysics Schemes For East Asia, Dean J. Carter Mar 2002

Verification Of Mm5 Cloud Microphysics Schemes For East Asia, Dean J. Carter

Theses and Dissertations

Using the 3-Dimensional Variational Analysis data assimilation scheme and the (MM5), input observations were denied in three different categories: total, upper air, and surface observation denial. Two control groups were run using all available data as received by AFWA. The main control group used a 6 hours old first guess as a baseline. The data denied test cases and the secondary control group used a 30-hour old first guess because it was not possible to deny data from the first guess. The secondary control group was used to estimate errors resulting from the use of different first guess forecasts between …

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Verification And Comparison Of Polar Mm5 And Afwa Mm5 Forecasts Over Alaska, William E. Courtemanche Mar 2002

Verification And Comparison Of Polar Mm5 And Afwa Mm5 Forecasts Over Alaska, William E. Courtemanche

Theses and Dissertations

This research compares biases of the Reisner Mixed-Phase Explicit Moisture Microphysics graupel and non-granpel schemes to determine if including graupel and riming processes within the Fifth Generation Mesoscale Model (MM5) will lead to improved forecasts of winter precipitation for Korea and Japan. MM5 forecasts were generated every 12 hours for a 20 days case period from January 1998. Model derived meteorological fields were interpolated to the station coordinates of four verification sites within the East Asian domain and radiosonde observations were used to compare the differences between the average temperature and water vapor errors of the two cloud microphysics schemes. …

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Exploration Of Teleconnection Indices For Long-Range Seasonal Temperature Forecasts, Robb M. Randall Mar 2002

Exploration Of Teleconnection Indices For Long-Range Seasonal Temperature Forecasts, Robb M. Randall

Theses and Dissertations

The goal of this research was to examine the possibility of establishing guidance for lightning avoidance and lightning warning criteria based upon lightning radar reflectivity signatures. Determining how far naturally occurring lightning normally travels from thunderstorms can provide insight to decision makers concerning in-flight and ground safety measures. 3D lightning data are merged with archived weather radar data. To analyze the radar characteristics of the lightning data, radar data are interpolated to a 3D grid of reflectivity. Lightning flashes were analyzed to resolve the reflectivity of the flash origin and to determine the distance of the flash origin from the …

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Synthesis Of 3-Dimensional Lightning Data And Weather Radar Data To Determine The Distance That Naturally Occurring Lightning Travels From Thunderstorms, Lee A. Nelson Mar 2002

Synthesis Of 3-Dimensional Lightning Data And Weather Radar Data To Determine The Distance That Naturally Occurring Lightning Travels From Thunderstorms, Lee A. Nelson

Theses and Dissertations

Military base weather stations are required to issue lightning warnings to protect military equipment and personnel. The issuance of warnings is based on a 5 nautical mile (n mi) distance criterion. This criterion appears to have evolved over time as a balance between safety and mission impact. The goal of this thesis is to challenge the 5 n mi lightning warning criteria by quantifying the distance that CG lightning travels. A secondary goal is to examine the characteristics of the peak current of CG lightning strokes to determine if a relationship exists between peak current, the distance a stroke travels, …

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A Multiple Ant Colony Metaheuristic For The Air Refueling Tanker Assignment Problem, Ronjon Annaballi Mar 2002

A Multiple Ant Colony Metaheuristic For The Air Refueling Tanker Assignment Problem, Ronjon Annaballi

Theses and Dissertations

The performance of the Nuclear Facility (NFAC) incident module in modeling a nuclear reactor accident is evaluated. Fallout predictions are compared with air concentration measurements of I-131 in Europe over a five-day period. Two categories of source term specifications are used: NFAC-generated source terms based on plant conditions and accident severity, and user-defined source terms based on specifying the release of I-131. The Atmospheric Transport Model Evaluation Study report source term provided the needed detailed release information. The Air Force Combat Climatology Center provided weather data covering Europe during the release's 11-day duration. For the NFAC-generated source terms as few …

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Analysis Of Gps Satellite Allocation For The United States Nuclear Detonation Detection System (Usnds), Aaron J. Bell Mar 2002

Analysis Of Gps Satellite Allocation For The United States Nuclear Detonation Detection System (Usnds), Aaron J. Bell

Theses and Dissertations

We present an approach for identifying salient input features in high feature to exemplar ratio conditions. Basically we modify the SNR saliency-screening algorithm to improve the solution of the optimal salient feature subset problem. We propose that applying the SNR method to randomly selected subsets (SRSS) has a superior potential to identify the salient features than the traditional SNR algorithm has. Two experimental studies are provided to demonstrate the consistency of the SRSS. In the first experiment we used a noise-corrupted version of the Fisher s Iris classification problem. The first experiment designed to prove the fidelity of the SRSS …

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Selecting Salient Features In High Feature To Exemplar Ratio Conditions, Ismail Aslan Mar 2002

Selecting Salient Features In High Feature To Exemplar Ratio Conditions, Ismail Aslan

Theses and Dissertations

A key tenet to the Air Force's vision of Global Vigilance, Reach, and Power is the ability to project power via the use of aerial refueling. Scheduling of limited tanker resources is a major concern for Air Mobility Command (AMC). Currently the Combined Mating and Ranging Planning System (CMARPS) is used to plan aerial refueling operations, however due to the complex nature of the program and the length of time needed to run a scenario, the need for a simple tool that runs in much shorter time is desired. Ant colony algorithms are recently developed heuristics for finding solutions to …

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Modeling And Analysis Of Multicommodity Network Flows Via Goal Programming, Matthew A. Scott Mar 2002

Modeling And Analysis Of Multicommodity Network Flows Via Goal Programming, Matthew A. Scott

Theses and Dissertations

In this research we focused on the mobility system modeled by the AMC mobility planner's calculator (AMPCALC). We developed AMPCALC as a user-friendly tool and allow the user to easily carry out strategic airlift, air refueling and aeromedical evacuation calculations that are covered in Air Force Pamphlet 10-1403. In this study, Excel software and its macro language, Visual Basic for Application, are our two main tools. In the methodology of the thesis we examined fundamental aspects of the mobility system in AMPCALC. We discussed formulation logic of the mobility cycle. We presented ramp use optimization and tanker optimization processes. We …

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Modeling The Pre-Positioning Of Air Force Precision Guided Munitions, Daniel P. Johnstone Mar 2002

Modeling The Pre-Positioning Of Air Force Precision Guided Munitions, Daniel P. Johnstone

Theses and Dissertations

There exist factors that play a major role in an enlisted Airman's decision to either stay on active duty in the Air Force or separate. The current force structure of the U.S. Air Force and increased loss of enlisted personnel is a major concern as we look at maintaining manpower to meet the needs of the Air Force. The Air Force is reacting to this low retention problem by increasing the bonuses for initial enlistments and reenlistments, home basing, increasing quality of life for Air Force personnel with enlisted dormitory plus-ups, and under AEF personnel have increased predictability of deployment. …

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Robust Sensitivity Analysis For Multi-Attribute Deterministic Hierarchical Value Models, Yucel R. Kahraman Mar 2002

Robust Sensitivity Analysis For Multi-Attribute Deterministic Hierarchical Value Models, Yucel R. Kahraman

Theses and Dissertations

The Air Force's ability to deploy, employ, and sustain operations in forward locations is a key to mission success. An integral part of this strategy is equipment pre-positioning, to include: vehicles, aircraft support, consumable inventory, and munitions. This research focuses on defining and developing a model to aid decision makers with the afloat pre-positioning and deployment of munitions in an effort to ensure that the right weapons are available when, and where needed. This research places a particular focus on the strategic, global pre-positioning of the Afloat Pre-positioning Fleet (APF) in an effort to minimize the overall response time involved …

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Design And Fabrication Of Micro-Electro-Mechanical Structures For Tunable Micro-Optical Devices, Michael C. Harvey Mar 2002

Design And Fabrication Of Micro-Electro-Mechanical Structures For Tunable Micro-Optical Devices, Michael C. Harvey

Theses and Dissertations

Tunable micro-optical devices are expected to be vital for future military optical communication systems. In this research I seek to optimize the design of a microelectromechanical (MEM) structure integrated with a III-V semiconductor micro-optical device. The resonant frequency of an integrated optical device, consisting of a Fabry-Perot etalon or vertical cavity surface emitting laser (VCSEL), may be tuned by applying an actuation voltage to the MEM Flexure, thereby altering the device's optical cavity length. From my analysis I demonstrate tunable devices compatible with conventional silicon 5V integrated circuit technology. My design for a Fabry-Perot etalon has a theoretical tuning range …

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The Combined Effects Of Freestream Turbulence, Pressure Gradients, And Surface Roughness On Turbine Aerodynamics, Christine P. Ellering Mar 2002

The Combined Effects Of Freestream Turbulence, Pressure Gradients, And Surface Roughness On Turbine Aerodynamics, Christine P. Ellering

Theses and Dissertations

This work used scaled facsimiles of real turbine blade surfaces to characterize correlations between turbine blade roughness, freestream turbulence, pressure gradients and skin friction (Cf). Addition of roughness caused Cf to increase: up to 300% for the roughest surface. Addition of freestream turbulence resulted in 125% increase for the same surface. The combined effects showed increases up to 380%. Although decreasing roughness, freestream turbulence, and Reynolds number resulted in less dramatic results, it was concluded that the Cf increases due to combined effects were consistently higher than their corresponding sum of the parts. The combined effects of roughness and pressure …

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Fabrication And Cold-Flow Testing Of Subscale Space-Based Laser Geometry, Scott E. Bergren Mar 2002

Fabrication And Cold-Flow Testing Of Subscale Space-Based Laser Geometry, Scott E. Bergren

Theses and Dissertations

The objectives of this research were to build a facility that could simulate the expected fluid flow properties in the conceptual Space Based Laser Integrated Flight Experiment (SBL IFX) gas dynamic laser using cold-flow, and to investigate the performance of the model. A 1/5th scale model was fabricated and mated to a blow-down/vacuum wind tunnel. Using rapid data acquisition and schlieren photography the diffuser was determined to initially produce similar fluid flow to the SBL IFX, but rapidly became subsonic due to a transient normal shock wave formed when the wind tunnel was started.

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Investigation Of Cooperative Behavior In Autonomous Wide Search Munitions, Robert E. Dunkel Iii Mar 2002

Investigation Of Cooperative Behavior In Autonomous Wide Search Munitions, Robert E. Dunkel Iii

Theses and Dissertations

The purpose of this research is to investigate the effectiveness of wide-area search munitions in various scenarios using different cooperative behavior algorithms. The general scenario involves multiple autonomous munitions searching for an unknown number of targets of different priority in unknown locations. Three cooperative behavior algorithms are used in each scenario: no cooperation, cooperative attack only, and cooperative classification and attack. In the cooperative cases, the munitions allocate tasks on-line as a group, using linear programming techniques to determine the optimum allocation. Each munition provides inputs to the task allocation routine in the form of probabilities of successfully being able …

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Periodic Methods For Controlling A Satellite In Formation, Erin Y. Carraher Mar 2002

Periodic Methods For Controlling A Satellite In Formation, Erin Y. Carraher

Theses and Dissertations

Precise position determination and control is necessary to accomplish proposed satellite formation flying missions of ground movement target indication and synthetic aperture radar. This thesis combines the estimation and control techniques of past AFIT theses with various time-varying and time-invariant LQG control methods. Linear time-invariant control is ideal for on-board satellite estimation and control applications, freeing-up the satellite's limited computational capacity. Using a dynamics frame transformation from the nodal frame to an orbital frame, a higher fidelity, time-periodic model produced nearly identical results for either time-varying or time-invariant control for many scenarios. Scenarios included initial perturbations in the radial, in-track, …

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Carrier Dynamics In Mid-Infrared Quantum Well Lasers Using Time-Resolved Photoluminescence, Steven M. Gorski Mar 2002

Carrier Dynamics In Mid-Infrared Quantum Well Lasers Using Time-Resolved Photoluminescence, Steven M. Gorski

Theses and Dissertations

Research in mid-infrared laser technology has uncovered numerous applications for commercial and government use. A limiting factor for mid-infrared semiconductors is nonradiative recombination, which is a process that produces excess heat without emitting a photon. Nonradiative recombination mechanisms occur over a short time period and difficult to measure. Growth methods have significantly reduced the nonradiative recombination in some materials. The objective of this research is to further the understanding of how quantum well structures impact carrier recombination. InAsSb/InAlASb and InAs/GaInSb quantum well structures were studied with time-resolved photoluminescence utilizing upconversion, a non-linear wave mixing technique. This research reports Shockley-Read-Hall, radiative, …

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A Generalized Decision Support System For The Contracting Career Field, Larry D. Mercier Jr. Mar 2002

A Generalized Decision Support System For The Contracting Career Field, Larry D. Mercier Jr.

Theses and Dissertations

This research effort develops a generalized decision support system (DSS) to assist contracting career field managers in making recruiting and retention decisions. The DSS focuses on the skill level inventories of the contracting enlisted force. The interest in this research was identified by contracting career field managers due to the recent negative trends in recruitment and retention and the lack of analytical tools available. To accomplish this objective manpower models were developed using a combination of techniques gathered through interviews with Army and Air Force analysts and a literature review focusing on manpower modeling. The models developed in this study …

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Forecasting Research & Development Program Budgets Using The Weibull Model, Thomas W. Brown Mar 2002

Forecasting Research & Development Program Budgets Using The Weibull Model, Thomas W. Brown

Theses and Dissertations

Norden (1970) uses the Rayleigh, which is a degenerative of the Weibull, to model manpower on research and development (R&D) programs. Several research efforts extend his work including Lee, Hogue, and Gallagher (1997) who build R&D program budgets based on Rayleigh expenditures. We demonstrate the theoretical limitations to the Rayleigh model and present the Weibull model, which mitigates those limitations. Using 102 completed R&D defense programs, we develop regression models to predict the requisite shape and scale parameters to forecast Weibull-based budgets. Using the remaining 26 completed R&D programs to validate the robustness of our regression models, we show that …

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Performance Evaluation Of Hyperbolic Position Location Technique In Cellular Wireless Networks, Hakan Senturk Mar 2002

Performance Evaluation Of Hyperbolic Position Location Technique In Cellular Wireless Networks, Hakan Senturk

Theses and Dissertations

This study addresses the wireless geolocation problem that has been an attractive subject for the last few years after Federal Communications Commission (FCC) mandate for wireless service providers to locate emergency 911 users with a high degree of accuracy -within a radius of 125 meters, 67 percent of the time by October 2001. There are a number of different geolocation technologies that have been proposed. These include, Assisted GPS (A-GPS), network-based technologies such as Enhanced Observed Time Difference (E-OTD), Time Difference of Arrival (TDOA), Angle of Arrival (AOA), and Cell of Origin (COO). This research focuses on network based techniques, …

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Using Relational Schemata In A Computer Immune System To Detect Multiple-Packet Network Intrusions, John L. Bebo Mar 2002

Using Relational Schemata In A Computer Immune System To Detect Multiple-Packet Network Intrusions, John L. Bebo

Theses and Dissertations

Given the increasingly prominent cyber-based threat, there are substantial research and development efforts underway in network and host-based intrusion detection using single-packet traffic analysis. However, there is a noticeable lack of research and development in the intrusion detection realm with regard to attacks that span multiple packets. This leaves a conspicuous gap in intrusion detection capability because not all attacks can be found by examining single packets alone. Some attacks may only be detected by examining multiple network packets collectively, considering how they relate to the "big picture," not how they are represented as individual packets. This research demonstrates a …

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Ontological Engineering And Mapping In Multiagent Systems Development, Jonathan M. Dileo Mar 2002

Ontological Engineering And Mapping In Multiagent Systems Development, Jonathan M. Dileo

Theses and Dissertations

Multiagent systems have received much attention in recent years due to their advantages in complex, distributed environments. Previous work at the Air Force Institute of Technology has developed a methodology for analyzing, designing, and developing multiagent systems, called Multiagent Systems Engineering (MaSE). MaSE currently does not address the information domain of the system, which is an integral part of designing proper system execution. This research extends the MaSE methodology to include the use of ontologies for information domain specification. The extensions allow the designer to specify information flow by using objects from the ontology as parameters in agent conversations. The …

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A Collaborative Visualization Framework Using Jini™ Technology, Chad M. Harris Mar 2002

A Collaborative Visualization Framework Using Jini™ Technology, Chad M. Harris

Theses and Dissertations

It is difficult to achieve mutual understanding of complex information between individuals that are separated geographically. Two well-known techniques commonly used to deal with this difficultly are collaboration and information visualization. This thesis develops a generic flexible framework that supports both collaboration and information visualization. It introduces the Collaborative Visualization Environment (COVE) framework, which simplifies the development of real-time synchronous multi-user applications by decoupling the elements of collaboration from the application. This allows developers to focus on building applications and leave the difficulties of collaboration (i.e., concurrency controls, user awareness, session management, etc.) to the framework. The framework uses an …

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Application Of Information Retrieval Techniques To Heterogeneous Databases In The Virtual Distributed Laboratory, Rodney D. Lykins Mar 2002

Application Of Information Retrieval Techniques To Heterogeneous Databases In The Virtual Distributed Laboratory, Rodney D. Lykins

Theses and Dissertations

The Department of Defense (DoD) maintains thousands of Synthetic Aperture Radar (SAR), Infrared (IR), Hyper-Spectral intelligence imagery and Electro-Optical (EO) target signature data. These images are essential to evaluating and testing individual algorithm methodologies and development techniques within the Automatic Target Recognition (ATR) community. The Air Force Research Laboratory Sensors Directorate (AFRL/SN) has proposed the Virtual Distributed Laboratory (VDL) to maintain a central collection of the associated imagery metadata and a query mechanism to retrieve the desired imagery. All imagery metadata is stored in relational database format for access from agencies throughout the federal government and large civilian universities. Each …

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Smart Structures For Control Of Optical Surfaces, D. Michael Sobers Jr. Mar 2002

Smart Structures For Control Of Optical Surfaces, D. Michael Sobers Jr.

Theses and Dissertations

The development of lightweight, large-aperture optics is of vital importance to the Department of Defense and the US Air Force for advancing remote sensing applications and improving current capabilities. Synthetic polymer optics offer weight and flexibility advantages over current generation glass mirrors, but require active control to maintain tight surface figure tolerances. This research explores the feasibility of using imbedded piezoelectric materials to control optical surfaces. Membrane-based and stiff piezo-controlled mirrors were constructed to develop and validate control techniques. Test results verified that surface control on the order of tens of wavelengths is possible using these systems.

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