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The Navigation Potential Of Ground Feature Tracking, Guner Mutlu
The Navigation Potential Of Ground Feature Tracking, Guner Mutlu
Theses and Dissertations
This research effort examines the reduction of error in inertial navigation aided by vision. This is part of an effort focused on navigation in a GPS denied environment. The navigation concept examined here consists of two main steps. First, extract the position of a tracked ground object using vision and geo-locate it in 3 dimensional navigation frame. In this first step multiple positions of the UAV are assumed known; think of a synthetic aperture. The only information about the tracked ground objects/features is the unit vector that points to the objects from the center of the camera. Two such vectors …
Formation Flight Of Earth Satellites On Kam Tori, Christopher T. Craft
Formation Flight Of Earth Satellites On Kam Tori, Christopher T. Craft
Theses and Dissertations
Kolmogorov, Arnold and Moser (KAM) theory provides that orbits of satellites whose dynamics are representable by an integrable Hamiltonian plus a small, real perturbation lie on tori in phase space and remain on the KAM tori for all time, unless acted upon by a non-conservative force. A refined technique for constructing KAM tori for Earth-orbiting satellites is developed and implemented using numerically integrated orbital data for hypothetical satellites and involving methods of Fourier analysis and spectral decomposition. Definition of satellite formations on the KAM tori is performed and analyses conducted to investigate both constellations with large separations and clusters with …
Application Of Dual-Tree Complex Wavelet Transforms To Burst Detection And Rf Fingerprint Classification, Randall W. Klein
Application Of Dual-Tree Complex Wavelet Transforms To Burst Detection And Rf Fingerprint Classification, Randall W. Klein
Theses and Dissertations
This work addresses various Open Systems Interconnection (OSI) Physical (PHY) layer mechanisms to extract and exploit RF waveform features (”fingerprints”) that are inherently unique to specific devices and that may be used to provide hardware specific identification (manufacturer, model, and/or serial number). This is addressed by applying a Dual-Tree Complex Wavelet Transform (DT-CWT) to improve burst detection and RF fingerprint classification. A ”Denoised VT” technique is introduced to improve performance at lower SNRs, with denoising implemented using a DT-CWT decomposition prior to Traditional VT processing. A newly developed Wavelet Domain (WD) fingerprinting technique is presented using statistical WD fingerprints with …
A Trust-Based Multiagent System, Richard S. Seymour, Gilbert L. Peterson
A Trust-Based Multiagent System, Richard S. Seymour, Gilbert L. Peterson
Faculty Publications
Cooperative agent systems often do not account for sneaky agents who are willing to cooperate when the stakes are low and take selfish, greedy actions when the rewards rise. Trust modeling often focuses on identifying the appropriate trust level for the other agents in the environment and then using these levels to determine how to interact with each agent. Adding trust to an interactive partially observable Markov decision process (I-POMDP) allows trust levels to be continuously monitored and corrected enabling agents to make better decisions. The addition of trust modeling increases the decision process calculations, and solves more complex trust …
Unified Behavior Framework For Reactive Robot Control, Brian G. Woolley, Gilbert L. Peterson
Unified Behavior Framework For Reactive Robot Control, Brian G. Woolley, Gilbert L. Peterson
Faculty Publications
Behavior-based systems form the basis of autonomous control for many robots. In this article, we demonstrate that a single software framework can be used to represent many existing behavior based approaches. The unified behavior framework presented, incorporates the critical ideas and concepts of the existing reactive controllers. Additionally, the modular design of the behavior framework: (1) simplifies development and testing; (2) promotes the reuse of code; (3) supports designs that scale easily into large hierarchies while restricting code complexity; and (4) allows the behavior based system developer the freedom to use the behavior system they feel will function the best. …
Effect Of Advanced Synthetically Enhanced Detector Resolution Algorithm On Specificity And Sensitivity Of Portable High Purity Germanium Gamma Detector Spectra, Latosha M. Bell
Theses and Dissertations
The ability to identify special nuclear material is one of the necessary prevention mechanisms for preventing proliferation of special nuclear materials. Additionally, if a nuclear event were to occur, information about the nuclear material used may be extracted from gamma spectra, provided it is obtained quickly and accurately. This can be made possible with the use of the exceptional resolution of the HPGe detector. This experiment applied the Advanced Synthetically Enhanced Detector Resolution Algorithm (ASEDRA) to a portable HPGe detector's spectra, to investigate whether improvements in specificity and sensitivity can be obtained. This method has been used to improve performance …
An Efficient And Effective Implementation Of The Trust System For Power Grid Compartmentalization, Juan M. Carlos Gonzalez
An Efficient And Effective Implementation Of The Trust System For Power Grid Compartmentalization, Juan M. Carlos Gonzalez
Theses and Dissertations
As utility companies develop and incorporate new technologies, such as moving to utility Internet technology based architecture and standard; it is crucial that we do so with history in mind. We know that traditional utility protection and control systems were not designed with security in their top priorities. This presents a danger in an environment where near real-time responses are required to ensure safe operations. As a consequence, system security becomes a burden to the system rather than necessary protection. Unfortunately, technology implementation is not the only concern. The number of utility privately-owned companies has multiplied as the market has …
System Identification Of An On Orbit Spacecraft's Antenna Dynamics, Christopher M. Sylvester
System Identification Of An On Orbit Spacecraft's Antenna Dynamics, Christopher M. Sylvester
Theses and Dissertations
As a result of previous efforts [Pachter, Barba, 2007] a tight control loop was designed to meet performance specifications while minimizing the feedback control system’s gains of a spacecraft mounted flexible antenna. Emphasis is now shifted to on orbit system identification of the antenna dynamics in order to increase nominal plant knowledge, estimate plant uncertainty bounds, as well as determine the disturbance band. Non-parametric system identification is undertaken. Knowledge of the plant dynamics along with the corresponding uncertainty bounds will provide for the design of a control system which meets the specifications (tracking and disturbance rejection) while at the same …
Developing Systems For Cyber Situational Awareness, James. S. Okolica, J. Todd Mcdonald, Gilbert L. Peterson, Robert F. Mills, Michael W. Haas
Developing Systems For Cyber Situational Awareness, James. S. Okolica, J. Todd Mcdonald, Gilbert L. Peterson, Robert F. Mills, Michael W. Haas
Faculty Publications
In both military and commercial settings, the awareness of Cyber attacks and the effect of those attacks on the mission space of an organization has become a targeted information goal for leaders and commanders at all levels. We present in this paper a defining framework to understand situational awareness (SA)—especially as it pertains to the Cyber domain—and propose a methodology for populating the cognitive domain model for this realm based on adversarial knowledge involved with Cyber attacks. We conclude with considerations for developing Cyber SA systems of the future.
Nondestructive Electromagnetic Material Characterization Using A Dual Waveguide Probe: A Full Wave Solution, Milo W. Hyde Iv, James W. Stewart, Michael J. Havrilla, William P. Baker, Edward Rothwell, Dennis P. Nyquist
Nondestructive Electromagnetic Material Characterization Using A Dual Waveguide Probe: A Full Wave Solution, Milo W. Hyde Iv, James W. Stewart, Michael J. Havrilla, William P. Baker, Edward Rothwell, Dennis P. Nyquist
Faculty Publications
A nondestructive technique for determining the complex permittivity and permeability of a perfect electric conductor backed magnetic shielding material using a dual waveguide probe is presented. The dual waveguide probe allows for the simultaneous collection of reflection and transmission coefficients which distinguishes it from single probe methods common in the literature. Theoretical development of these coefficients, which is accomplished through a coupled magnetic field integral equations formulation using Love's equivalence principle and solved via the method of moments (MOM), is discussed. Evaluation of the resulting MOM impedance matrix elements is performed using complex plane integration leading to enhanced computational efficiency …
Structural Optimization Of Joined-Wing Beam Model With Bend-Twist Coupling Using Equivalent Static Loads, Nicholas S. Green
Structural Optimization Of Joined-Wing Beam Model With Bend-Twist Coupling Using Equivalent Static Loads, Nicholas S. Green
Theses and Dissertations
This study is based on the merger of two separate theories to further the efficiency with which joined-wing structural models are designed. The first theory is Geometrically Exact Beam Theory (GEBT). GEBT is a small strain beam theory which is capable of accurately capturing the geometric bend-twist coupling in beam elements that are experiencing large global deformations. This is crucial to the joined-wing problem as it is geometrically nonlinear. The second theory concerns Equivalent Static Loads (ESL). These ESL consist of a load vector that produces the same nodal displacements and rotations as those computed from a pure nonlinear analysis. …
Time Domain Equalizer Design Using Bit Error Rate Minimization For Uwb Systems, Syed Imtiaz Husain, Jinhong Yuan, Jian Zhang, Richard K. Martin
Time Domain Equalizer Design Using Bit Error Rate Minimization For Uwb Systems, Syed Imtiaz Husain, Jinhong Yuan, Jian Zhang, Richard K. Martin
Faculty Publications
Ultra-wideband (UWB) communication systems occupy huge bandwidths with very low power spectral densities. This feature makes the UWB channels highly rich in resolvable multipaths. To exploit the temporal diversity, the receiver is commonly implemented through a Rake. The aim to capture enough signal energy to maintain an acceptable output signal-to-noise ratio (SNR) dictates a very complicated Rake structure with a large number of fingers. Channel shortening or time domain equalizer (TEQ) can simplify the Rake receiver design by reducing the number of significant taps in the effective channel. In this paper, we first derive the bit error rate (BER) of …
Air Force Institute Of Technology Research Report 2008, Office Of Research And Sponsored Programs, Graduate School Of Engineering And Management, Afit
Air Force Institute Of Technology Research Report 2008, Office Of Research And Sponsored Programs, Graduate School Of Engineering And Management, Afit
AFIT Documents
This report summarizes the research activities of the Air Force Institute of Technology’s Graduate School of Engineering and Management. It describes research interests and faculty expertise; lists student theses/dissertations; identifies research sponsors and contributions; and outlines the procedures for contacting the school. Included in the report are: faculty publications, conference presentations, consultations, and funded research projects. Research was conducted in the areas of Aeronautical and Astronautical Engineering, Electrical Engineering and Electro-Optics, Computer Engineering and Computer Science, Systems and Engineering Management, Operational Sciences, Mathematics, Statistics and Engineering Physics.
Influence Of Structural Flexibility On Flapping Wing Propulsion, Aaron M. Mcclung
Influence Of Structural Flexibility On Flapping Wing Propulsion, Aaron M. Mcclung
Theses and Dissertations
The inelastic deformation behavior of PMR-15 neat resin, a high-temperature thermoset polymer, was investigated at 288 degrees C. The experimental program was designed to explore the influence of strain rate on tensile loading, unloading, and strain recovery behaviors. In addition, the effect of the prior strain rate on the relaxation response of the material, as well as on the creep behavior following strain controlled loading were examined. The experimental data were modeled with the Viscoplasticity Based on Overstress (VBO) theory. A systematic procedure for determining model parameters was developed and the model was employed to predict the response of the …
Frequency Diversity For Improving Synthetic Aperture Radar Imaging, Jawad L. Farooq
Frequency Diversity For Improving Synthetic Aperture Radar Imaging, Jawad L. Farooq
Theses and Dissertations
In this work, a novel theoretical framework is presented for using recent advances in frequency diversity arrays (FDAs). Unlike a conventional array, the FDA simultaneously transmits a unique frequency from each element in the array. As a result, special time and space properties of the radiation pattern are exploited to improve cross-range resolution. The idealized FDA radiation pattern is compared with and validated against a full-wave electromagnetic solver, and it is shown that the conventional array is a special case of the FDA. A new signal model, based on the FDA, is used to simulate SAR imagery of ideal point …
Determining The Orbit Locations Of Turkish Airborne Early Warning And Control Aircraft Over The Turkish Air Space, Nebi Sarikaya
Determining The Orbit Locations Of Turkish Airborne Early Warning And Control Aircraft Over The Turkish Air Space, Nebi Sarikaya
Theses and Dissertations
The technology improvement affects the military needs of individual countries. The new doctrine of defense for many countries emphasizes detecting threats as far away as you can from your homeland. Today, the military uses both ground RADAR and Airborne Early Warning and Control (AEW&C) Aircraft. AEW&C aircraft has become vital to detect low altitude threats that a ground RADAR cannot detect because of obstacles on the earth. Turkey has ordered four AEW&C aircraft for her air defense system because of the lack of complete coverage by ground RADAR. This research provides optimal orbit locations that can be updated according to …
An Investigation Of Knowledge Transfer And Retention In A Government Procurement Office, Garland T. Mobley
An Investigation Of Knowledge Transfer And Retention In A Government Procurement Office, Garland T. Mobley
Theses and Dissertations
There is no measure for the loss of corporate memory. Organizations build a reservoir of knowledge in its employees, and this knowledge becomes a critical ingredient in an organization’s ability to carry out its mission. Knowledgeable people are extremely valuable and once they leave, their organizationally-applied knowledge leaves with them. This study introduces specific knowledge attributes that significantly impact effective tacit and explicit knowledge transfer and retention. Under this construct the proposed investigation explores a government program office to see if replacing experienced government employees with outsourced personnel impacts corporate knowledge retention. The study concludes that a loss of corporate …
Social Networking Website Users And Privacy Concerns: A Mixed Methods Investigation, Stephanie J. Mills
Social Networking Website Users And Privacy Concerns: A Mixed Methods Investigation, Stephanie J. Mills
Theses and Dissertations
Social networking websites are the fastest growing entity on the Internet. Users of social networking websites post personal information and pictures on these websites. Privacy and social networking websites has been previously studied, however, since those studies were conducted the rules for those websites have changed dramatically. A mixed methods approach was used in this study to examine what privacy concerns users of social networking websites have, whether it’s regarding information on their accounts or the pictures they have posted. This study also considered if there were common personality traits present in people with those concerns. A comparison of user …
Exploitation Of Geographic Information Systems For Vehicular Destination Prediction, Richard T. Muster
Exploitation Of Geographic Information Systems For Vehicular Destination Prediction, Richard T. Muster
Theses and Dissertations
Much of the recent successes in the Iraqi theater have been achieved with the aid of technology so advanced that celebrated journalist Bob Woodward recently compared it to the Manhattan Project of WWII. Intelligence, Surveillance, and Reconnaissance (ISR) platforms have emerged as the rising star of Air Force operational capabilities as they are enablers in the quest to track and disrupt terrorist and insurgent forces. This thesis argues that ISR systems have been severely under-exploited. The proposals herein seek to improve the machine-human interface of current ISR systems such that a predictive battle-space awareness may be achieved, leading to shorter …
Application Of Time-Frequency Representation To Non-Stationary Radar Cross Section, John D. Mcshane
Application Of Time-Frequency Representation To Non-Stationary Radar Cross Section, John D. Mcshane
Theses and Dissertations
Radar Cross Section (RCS) imaging of a non-wide sense stationary signal poses significant problems in identifying scattering centers in the post processed radar- generated image. A non-wide sense stationary RCS is typically encountered when moving parts on the target impress a phase shift into the backscatter signal that is uncorrelated to the previous return pulse. When the Fourier transform of the phase shifted complex signal is taken, range and cross range information on scattering centers are misplaced. Time Frequency Representations (TFR) must be used to help locate these scattering centers so they can be properly treated to reduce the target’s …
The Effect Of Values On System Development Project Outcomes, Daniel B. Ward
The Effect Of Values On System Development Project Outcomes, Daniel B. Ward
Theses and Dissertations
In order to understand why organizations make certain decisions and target certain outcomes, it is useful to understand their priorities and preferences, commonly referred to as “values.” This research explores the relationship between the technical values held by system development teams and the operational effectiveness of the systems those teams produce. Specifically, it examines the impact of a value set called FIST (Fast, Inexpensive, Simple, Tiny) on DoD and NASA system development projects, and investigates the correlation between the FIST values and operational outcomes. The findings show that the FIST value set enhances project stability, increases the project leader’s control …
Bit-Error-Rate-Minimizing Channel Shortening Using Post-Feq Diversity Combining And A Genetic Algorithm, Gokhan Altin
Bit-Error-Rate-Minimizing Channel Shortening Using Post-Feq Diversity Combining And A Genetic Algorithm, Gokhan Altin
Theses and Dissertations
In advanced wireline or wireless communication systems, i.e., DSL, IEEE 802.11a/g, HIPERLAN/2, etc., a cyclic prefix which is proportional to the channel impulse response is needed to append a multicarrier modulation (MCM) frame for operating the MCM accurately. This prefix is used to combat inter symbol interference (ISI). In some cases, the channel impulse response can be longer than the cyclic prefix (CP). One of the most useful techniques to mitigate this problem is reuse of a Channel Shortening Equalizer (CSE) as a linear preprocessor before the MCM receiver in order to shorten the effective channel length. Channel shortening filter …
Dynamic Network Formation Using Ant Colony Optimization, Steven C. Oimoen
Dynamic Network Formation Using Ant Colony Optimization, Steven C. Oimoen
Theses and Dissertations
Military and industry are moving toward every device being network enabled and connected for reliable availability of communication and information. To make this type of system a reality, the devices must be capable of forming a network topology on their own in a dynamic environment to ensure that the correct information reaches a desired location and on-time. This research presents three contributions for solving highly dynamic (i.e. drastic change within the network) Multi-commodity Capacitated Network Design Problems (MCNDPs) resulting in a distributed multi-agent network design algorithm. The first contribution incorporates an Ant Colony Optimization (ACO) algorithm Ant Colony System (ACS) …
Two Dimensional Scattering Analysis Of Data-Linked Support Strings For Bistatic Measurement Systems, William Keichel
Two Dimensional Scattering Analysis Of Data-Linked Support Strings For Bistatic Measurement Systems, William Keichel
Theses and Dissertations
Use of data-linked strings to support a bistatic antenna is being considered as a possible improvement to indoor bistatic radar cross section measurement systems. Analysis of candidate data-linked strings is required to understand the potential clutter contribution posed by such a system. The main objective of this research is to determine the scattering properties of four data-linked support string samples. An- other goal is to determine the material properties of the string material through nondestructive means if possible. The final goal is to model the samples as a single wire coated with a dielectric material and determine the validity of …
Shelter-In-Place: Indoor Exposure Assessment During An Airborne Chemical, Biological, Radiological, And Nuclear (Cbrn) Event, Robert D. Schmidtgoessling
Shelter-In-Place: Indoor Exposure Assessment During An Airborne Chemical, Biological, Radiological, And Nuclear (Cbrn) Event, Robert D. Schmidtgoessling
Theses and Dissertations
The goal of Shelter-In-Place (SIP) is to reduce human exposure to chemical, biological, radiological, and nuclear (CBRN) agents in the event of an accidental or intentional airborne release into the outdoor environment. The Air Force Bioenvironmental Engineering (BE) career field is responsible for providing hazard identification, evaluation, and control capabilities as well as executing health risk assessments to recommend appropriate courses of action to commanders pre-, trans-, and post-incident. Specifically, BE is responsible for providing sampling, identification, and quantification input to hazard prediction models and supporting evacuation plan development to provide risk-based control recommendations. This also includes providing exposure and …
Modeling And Simulation Architecture For Studying Doppler-Based Radar With Complex Environments, Nicholas J. Amato
Modeling And Simulation Architecture For Studying Doppler-Based Radar With Complex Environments, Nicholas J. Amato
Theses and Dissertations
This research effort develops a hybrid large-scale modeling and simulation frame- work that defines the requirements for a program to evaluate radar-aircraft-turbine- clutter interactions. Wind turbines and other moving structures can interfere with a radar’s ability to detect moving aircraft because radar returns from turbines are comparable to those from slow flying aircraft. This interference can lead to aircraft collisions or crashes, reducing the safety for air traffic. Two radar applications, INSSITE and IMOM, were investigated to determine which of the subsystems, in the proposed architecture, are currently available and which need additional development. Current radar applications either delve too …
A Framework For Analyzing Biometric Template Aging And Renewal Prediction, John W. Carls
A Framework For Analyzing Biometric Template Aging And Renewal Prediction, John W. Carls
Theses and Dissertations
Biometric technology and systems are modernizing identity capabilities. With maturing biometrics in full, rapid development, a higher accuracy of identity verification is required. An improvement to the security of biometric-based verification systems is provided through higher accuracy; ultimately reducing fraud, theft, and loss of resources from unauthorized personnel. With trivial biometric systems, a higher acceptance threshold to obtain higher accuracy rates increase false rejection rates and user unacceptability. However, maintaining the higher accuracy rate enhances the security of the system. An area of biometrics with a paucity of research is template aging and renewal prediction, specifically in regards to facial …
The Economic Impact Of A Radiological Dispersal Device (Rde), Michael T. Lebrun
The Economic Impact Of A Radiological Dispersal Device (Rde), Michael T. Lebrun
Theses and Dissertations
While it will not cause the devastation of a nuclear weapon, the radiological dispersal event (RDE) is particularly dangerous in that it has the potential to cause major economic disruptions. The purpose of this research was to develop a generalized methodology that can be used to assess economic impacts, resulting from a (RDE), occurring in any location and across any industry. Currently, there is no universal approach for measuring the costs or economic impacts on businesses, or a common framework for conducting an economic impact for a RDE. The objective of this research was to aid in the RDE response …
Forecasting Usaf Jp-8 Fuel Needs, Omer Saglam
Forecasting Usaf Jp-8 Fuel Needs, Omer Saglam
Theses and Dissertations
Oil is still one of the strategic energy resources for both the U.S. and the USAF today. Accurate oil prediction is important for the U.S. in order to improve the national strategy and the related budget concerns. Today, the U.S. is roughly importing 58% of its petroleum products. Moreover, in Fiscal Year (FY) 2007 the USAF total energy costs exceeded $6.9 billion. Aviation fuel accounted for approximately 81% of the total AF energy costs. Fluctuations in oil prices have huge impacts on the USAF’s JP-8 budgetary calculations. In order to handle this problem, the need for accurate forecasts arises. In …
Computational Analysis Of Geometric Effects On Strut Induced Mixing In A Scramjet Combustor, Matthew G. Bagg
Computational Analysis Of Geometric Effects On Strut Induced Mixing In A Scramjet Combustor, Matthew G. Bagg
Theses and Dissertations
In order to increase the fuel-air mixing in a scramjet combustion section, the Air Force Institute of Technology and the Air Force Research lab investigated methods to increase the mixing efficiency. Previous experimental work identified the advantages of using a strut upstream of a cavity flame holder to increase the fuel-air mixture. In this paper a computational investigation of strut injectors in a supersonic flow with a cavity flame holder is reported. This research focused on understanding the effect of a change in height and width of the strut upstream of the combustion cavity on the mixing efficiency and pressure …