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Deeply-Integrated Feature Tracking For Embedded Navigation, Jeffery R. Gray Mar 2009

Deeply-Integrated Feature Tracking For Embedded Navigation, Jeffery R. Gray

Theses and Dissertations

The Air Force Institute of Technology (AFIT) is investigating techniques to improve aircraft navigation using low-cost imaging and inertial sensors. Stationary features tracked within the image are used to improve the inertial navigation estimate. These features are tracked using a correspondence search between frames. Previous research investigated aiding these correspondence searches using inertial measurements (i.e., stochastic projection). While this research demonstrated the benefits of further sensor integration, it still relied on robust feature descriptors (e.g., SIFT or SURF) to obtain a reliable correspondence match in the presence of rotation and scale changes. Unfortunately, these robust feature extraction algorithms are computationally …


Advanced Radiometry For High Discrimination Explosive Fireball Discrimination, Steven E. Slagle Mar 2009

Advanced Radiometry For High Discrimination Explosive Fireball Discrimination, Steven E. Slagle

Theses and Dissertations

The high explosive fireball phenomenological model for the mid wave infrared spectrum, developed by AFIT, performs classification from spectral signatures was modified to use radiometric intensities. Five bands were sequentially fit to derive the five physical fit parameters describing the fireball's temperature, size, soot absorption coefficient within 16% and emissions from the H2O and CO2 concentrations within 333% of the spectral model. This was improved by changing the model's band sizes, center, and fitting methods where all five fit parameters were matched to within 17% of spectral model. This demonstrated that a combination of radiometric intensities could …


Model-Based Control Using Model And Mechanization Fusion Techniques For Image-Aided Navigation, Constance D. Hendrix Mar 2009

Model-Based Control Using Model And Mechanization Fusion Techniques For Image-Aided Navigation, Constance D. Hendrix

Theses and Dissertations

Unmanned aerial vehicles are no longer used for just reconnaissance. Current requirements call for smaller autonomous vehicles that replace the human in high-risk activities. Many times these activities are performed in GPS-degraded environments. Without GPS providing today's most accurate navigation solution, autonomous navigation in tight areas is more difficult. Today, image-aided navigation is used and other methods are explored to more accurately navigate in such areas (e.g., indoors). This thesis explores the use of inertial measurements and navigation solution updates using cameras with a model-based Linear Quadratic Gaussian controller. To demonstrate the methods behind this research, the controller will provide …


Host-Based Multivariate Statistical Computer Operating Process Anomaly Intrusion Detection System (Paids), Glen R. Shilland Mar 2009

Host-Based Multivariate Statistical Computer Operating Process Anomaly Intrusion Detection System (Paids), Glen R. Shilland

Theses and Dissertations

No abstract provided.


Value-Driven Enterprise Architecture Score: Evaluation Applied To Joint Force Protection Future State Design, Larry D. Cotton, Gary A. Haase Mar 2009

Value-Driven Enterprise Architecture Score: Evaluation Applied To Joint Force Protection Future State Design, Larry D. Cotton, Gary A. Haase

Theses and Dissertations

This research presents a methodology to evaluate the quality of a system's architecture using principles drawn from Value-Focused Thinking (VFT) and resulting in a Value-Driven Enterprise Architecture Score (VDEA-Score). This is an overall numerical architecture quality score useful to a system's management team to identify the advantages and disadvantages of a system design and associated architecture documentation or to track its quality across discrete evaluation epochs. This effort determined which aspects of the architecture are most valuable to the stakeholder in the areas of (1) the system effectiveness values (quality of the instantiated system being represented and its ability to …


Surface Acoustic Wave Devices As Chemical Vapor Sensors, Daniel Gallagher Mar 2009

Surface Acoustic Wave Devices As Chemical Vapor Sensors, Daniel Gallagher

Theses and Dissertations

In order to effectively neutralize non-traditional threats to US forces and population such as improvised explosive devices (IED) and chemical, biological, radio- logical, nuclear, and explosive (CBNRE) weapons, a flexible vapor sensor platform is proposed. This work involves the design, fabrication, and testing of coated surface acoustic wave devices for vapor sensing ability. Devices were fabricated in-house using MEMS fabrication techniques, then coated with a thin layer of a Nafion polymer. The frequency response of coated devices displayed 2 MHz frequency shifts around the resonance frequency upon introduction of ethanol vapors into the nitrogen vapor stream. This indicates strong sensing …


Using Agent-Based Modeling To Evaluate Uas Behaviors In A Target-Rich Environment, Joseph A. Van Kuiken Mar 2009

Using Agent-Based Modeling To Evaluate Uas Behaviors In A Target-Rich Environment, Joseph A. Van Kuiken

Theses and Dissertations

The trade-off between accuracy and speed is a re-occurring dilemma in many facets of military performance evaluation. This is an especially important issue in the world of ISR. One of the most progressive areas of ISR capabilities has been the utilization of Unmanned Aircraft Systems (UAS). Many people believe that the future of UAS lies in smaller vehicles flying in swarms. We use the agent-based System Effectiveness and Analysis Simulation (SEAS) to create a simulation environment where different configurations of UAS vehicles can process targets and provide output that allows us to gain insight into the benefits and drawbacks of …


The Hybrid Counterinsurgency Strategy: System Dynamics Employed To Develop A Behavioral Model Of Joint Strategy, Ferdinand Maldonado Mar 2009

The Hybrid Counterinsurgency Strategy: System Dynamics Employed To Develop A Behavioral Model Of Joint Strategy, Ferdinand Maldonado

Theses and Dissertations

Since the recent focus on the Global War on Terror, both military and civilian theorists have begun to “relearn” the intricacies of counterinsurgency warfare. We face difficult challenges when confronting non-state actors that tend to attack in the time between conventional battles and the establishment of stable governments. This research compares and contrasts current counterinsurgency strategies (Hearts and Minds and Cost Benefit Theory) by applying System Dynamics to provide insight into the influences and emergent behavior patterns of counterinsurgency systems. The information gained from the development of the models and from their simulation behaviors is used to construct a System …


Abstracting Gis Layers From Hyperspectral Imagery, Torsten E. Howard Mar 2009

Abstracting Gis Layers From Hyperspectral Imagery, Torsten E. Howard

Theses and Dissertations

Modern warfare methods in the urban environment necessitates the use of multiple layers of sensors to manage the battle space. Hyperspectral imagers are one possible sensor modality to provide remotely sensed images that can be converted into Geographic Information Systems (GIS) layers. GIS layers abstract knowledge of roads, buildings, and scene content and contain shape files that outline and highlight scene features. Creating shape files is a labor-intensive and time-consuming process. The availability of shape files that reflect the current configuration of an area of interest significantly enhances Intelligence Preparation of the Battlespace (IPB). The solution presented in this thesis …


Numerical Analysis For Relevant Features In Intrusion Detection (Narfid), Jose Andres Gonzalez Mar 2009

Numerical Analysis For Relevant Features In Intrusion Detection (Narfid), Jose Andres Gonzalez

Theses and Dissertations

Identification of cyber attacks and network services is a robust field of study in the machine learning community. Less effort has been focused on understanding the domain space of real network data in identifying important features for cyber attack and network service classification. Motivations for such work allow for anomaly detection systems with less requirements on data “sniffed” off the network, extraction of features from the traffic, reduced learning time of algorithms, and ideally increased classification performance of anomalous behavior. This thesis evaluates the usefulness of a good feature subset for the general classification task of identifying cyber attacks and …


The Evaluation Of Rekeying Protocols Within The Hubenko Architecture As Applied To Wireless Sensor Networks, Cory J. Antosh Mar 2009

The Evaluation Of Rekeying Protocols Within The Hubenko Architecture As Applied To Wireless Sensor Networks, Cory J. Antosh

Theses and Dissertations

This thesis investigates the impact of using three different rekeying protocols–pair-wise, hierarchical, and Secure Lock within a wireless sensor network (WSN) under the Hubenko architecture. Using a Matlab computer simulation, the impact of the three rekeying protocols on the number of bits transmitted across the network and the amount of battery power consumed in WSN nodes during rekey operations is investigated. Baseline pair-wise rekeying performance can be improved by using either Secure Lock or hierarchical rekeying. The best choice depends on the size of the WSN and the size of the key used. Hierarchical rekeying is the best choice for …


Communication Free Robot Swarming, Zachary C. Gray Feb 2009

Communication Free Robot Swarming, Zachary C. Gray

Theses and Dissertations

As the military use of unmanned aerial vehicles increases, a growing need for novel strategies to control these systems exists. One such method for controlling many unmanned aerial vehicles simultaneously is the through the use of swarm algorithms. This research explores a swarm robotic algorithm developed by Kadrovach implemented on Pioneer Robots in a real-world environment. An adaptation of his visual sensor is implemented using stereo vision as the primary method of sensing the environment. The swarm members are prohibited from explicitly communicating other than passively through the environment. The resulting implementation produces a communication free swarming algorithm. The algorithm …


Small-Signal Impedance Measurement Of Power-Electronics-Based Ac Power Systems Using Line-To-Line Current Injection, Jing Huang, Keith Corzine, M. Belkhayat Feb 2009

Small-Signal Impedance Measurement Of Power-Electronics-Based Ac Power Systems Using Line-To-Line Current Injection, Jing Huang, Keith Corzine, M. Belkhayat

Electrical and Computer Engineering Faculty Research & Creative Works

Naval ships as well as aerospace power systems are incorporating a greater degree of power electronic switching sources and loads. Although these components provide exceptional performance, they are prone to instability due to their high efficiency and constant power characteristics that can exhibit negative impedance nature at certain frequencies. When designing these systems, integrators must consider the impedance versus frequency at an interface (which designates source and load). Stability criteria have been developed in terms of source and load impedances for both dc and ac systems, and it is often helpful to have techniques for impedance measurement. For dc systems, …


Evaluation Of The Effects Of Powder Coating Cure Temperatures On The Mechanical Properties Of Aluminum Alloy Substrates, C. Maldonado, D. Diaz, J. Ranallo, R. Painter, W. Dahir, D. Hassouna, B. Gayer, E. Toss, I. Martinez, P. Stoyanov, J. Ogren, E. W. Lee, D. Piatkowski, Omar S. Es-Said Feb 2009

Evaluation Of The Effects Of Powder Coating Cure Temperatures On The Mechanical Properties Of Aluminum Alloy Substrates, C. Maldonado, D. Diaz, J. Ranallo, R. Painter, W. Dahir, D. Hassouna, B. Gayer, E. Toss, I. Martinez, P. Stoyanov, J. Ogren, E. W. Lee, D. Piatkowski, Omar S. Es-Said

Mechanical Engineering Faculty Works

The effects of curing temperature, based on new, low-temperature powder coating methods and traditional high-temperature powder coating methods, were studied. Heat-sensitive aluminum alloys (2024-T3, 6061-T6, and 7075-T6) were subjected to two different heat-treatment cycles, which were based on temperatures of 121 and 204 degrees C. Findings indicate that although both cure temperatures achieved powder coatings adhesion and thickness appropriate for industrial uses, the high-temperature cure treatment negatively affected the mechanical properties.


Performance Of A Fire-And-Forget Anti-Tank Missile With A Damaged Wing, John Harris, Nathan Slegers Jan 2009

Performance Of A Fire-And-Forget Anti-Tank Missile With A Damaged Wing, John Harris, Nathan Slegers

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

A mathematical model is developed for an anti-tank missile and its guidance algorithms. The aerodynamic model is separated into two parts, the airframe and external lifting surfaces in order to model damage to the airframe. Radar data is compared to that of the proposed model and it is shown that the model accurately replicates the true flight dynamics. Two types of field handling damage are modeled, a damaged mid-body wing with 50% of its planform area missing, and an un-deployed mid-body wing. Monte Carlo simulations are performed for each type of damage and the eight possible mid-body wing locations. The …


Optimal Control For Terminal Guidance Of Autonomous Parafoils, Nathan Slegers, Oleg A. Yakimenko Jan 2009

Optimal Control For Terminal Guidance Of Autonomous Parafoils, Nathan Slegers, Oleg A. Yakimenko

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

This paper deals with the development of guidance, navigation and control algorithms for a prototype of a miniature aerial delivery system capable of high-precision maneuvering and high touchdown accuracy. High accuracy enables use in precision troop resupply, sensor placement, urban warfare reconnaissance, and other similar operations. Specifically, this paper addresses the terminal phase, where uncertainties in winds cause most of the problems. The paper develops a six degree-of-freedom model to adequately address dynamics and kinematics of the prototype delivery system and then reduces it to a two degrees-of-freedom model to develop a model predictive control algorithm for reference trajectory tracking …


United States Air Force Posture Statement 2009, U.S. Air Force Jan 2009

United States Air Force Posture Statement 2009, U.S. Air Force

United States Air Force: Publications

Today, the United States faces a spectrum of challenges to our national security and global interests. As an integral member of the Joint team, America’s Air Force provides the critical capabilities of Global Vigilance, Global Reach, and Global Power. The United States Air Force is 'All In" today’s Joint fight. At the same time, our investments in new capabilities will ensure we are ready for tomorrow’s challenges. The mission of the United States Air Force is to "fly, fight, and win…in air, space and cyberspace"—as an integral member of the Joint …


C2 Domain Ontology Within Our Lifetime, Leslie Winters, Andreas Tolk Jan 2009

C2 Domain Ontology Within Our Lifetime, Leslie Winters, Andreas Tolk

Computational Modeling & Simulation Engineering Faculty Publications

Agile Command and Control (C2) requires agile information sharing with an increasingly wide variety of military and non-military partners. While current net-centric approaches may improve information sharing within a particular niche of C2, they do not support information sharing across the larger C2 domain. Although not a silver bullet, the development and application of a C2 domain ontology to improve C2 data and service integration appears to be increasingly realistic. In fact, there are several examples of successful ontology applications in domains such as medicine, biology, and engineering, and the new discipline of Applied Ontology is emerging. C2 data, architecture, …


Conceptual Requirements For Command And Control Languages, Andreas Tolk, Curtis L. Blais, Saikou Y. Diallo, Charles Turnitsa Jan 2009

Conceptual Requirements For Command And Control Languages, Andreas Tolk, Curtis L. Blais, Saikou Y. Diallo, Charles Turnitsa

Computational Modeling & Simulation Engineering Faculty Publications

The current Coalition Battle Management Language initiative (C-BML) will define a language to unambiguously exchange command and control information between systems. This paper introduces a categorization that may be used to guide the process of developing C-BML effectively by enumerating the conceptual requirements the authors have identified in model-based data engineering and process engineering based studies in various domains.

First, it is important to distinguish if application of the language will support the planning, execution, or observation phase of command and control. While C-BML already distinguishes between tasking and reporting, planning is a category with different requirements.

Second, the language …


Applying Model-Based Data Engineering To Evaluate The Alignment Of Information Modeled Within Jc3iedm, Msdl, And Matrex-Fom, Anil Ustun, Andreas Tolk, Saikou Diallo Jan 2009

Applying Model-Based Data Engineering To Evaluate The Alignment Of Information Modeled Within Jc3iedm, Msdl, And Matrex-Fom, Anil Ustun, Andreas Tolk, Saikou Diallo

Computational Modeling & Simulation Engineering Faculty Publications

The need for a common representation of entities and their relations to support the easier composition and federation of independently developed solutions in support of the user has been identified and addressed in several papers presented during recent simulation interoperability workshop. One of the underlying assumptions is that standards derived from the same conceptual domain can easily be converted into each others, as they deal with the same concepts. In a project conducted for the U.S. Army’s Program Executive Office (PEO) Soldier, three of such solutions for military operations (with focus on the land forces) were utilized to capture the …


Graduate School Academic Catalog 2009-2010, Graduate School Of Engineering And Management, Air Force Institute Of Technology Jan 2009

Graduate School Academic Catalog 2009-2010, Graduate School Of Engineering And Management, Air Force Institute Of Technology

AFIT Documents

The Graduate Catalog represents the offerings, programs, and requirements in effect at the time of publication.


Robust Estimation And Adaptive Guidance For Multiple Uavs' Cooperation, Randal Allen Jan 2009

Robust Estimation And Adaptive Guidance For Multiple Uavs' Cooperation, Randal Allen

Electronic Theses and Dissertations

In this paper, an innovative cooperative navigation method is proposed for multiple Unmanned Air Vehicles (UAVs) based on online target position measurements. These noisy position measurement signals are used to estimate the target's velocity for non-maneuvering targets or the target's velocity and acceleration for maneuvering targets. The estimator's tracking capability is physically constrained due to the target's kinematic limitations and therefore is potentially improvable by designing a higher performance estimator. An H-infinity filter is implemented to increase the robustness of the estimation accuracy. The performance of the robust estimator is compared to a Kalman filter and the results illustrate more …


Direct Manipulation Of Virtual Objects, Long Nguyen Jan 2009

Direct Manipulation Of Virtual Objects, Long Nguyen

Electronic Theses and Dissertations

Interacting with a Virtual Environment (VE) generally requires the user to correctly perceive the relative position and orientation of virtual objects. For applications requiring interaction in personal space, the user may also need to accurately judge the position of the virtual object relative to that of a real object, for example, a virtual button and the user's real hand. This is difficult since VEs generally only provide a subset of the cues experienced in the real world. Complicating matters further, VEs presented by currently available visual displays may be inaccurate or distorted due to technological limitations. Fundamental physiological and psychological …


Spectral And Spatial Analysis Of False Alarms In Airborne Minefield Data, Abhishek Sanaka Jan 2009

Spectral And Spatial Analysis Of False Alarms In Airborne Minefield Data, Abhishek Sanaka

Masters Theses

"Tests run in May 2005 at an arid site as part of airborne minefield detection yielded substantial airborne background data with ground truthed and surveyed false alarm locations. ERDC and MultiSensor LLC identified the locations, geo referenced and documented different false alarms. The project reported here built a self-contained database of image chips recording target signatures for MSI (four bands) and MWIR sensors for false alarms from this background data and mines from related areas. The image chips represent various days, times of day, altitudes, as well as several different sources of false alarm and mine types. The database facilitates …


Continuous-Flow, Rapid Lysis Devices For Biodefense Nucleic Acid Diagnostic Systems, Robert W. Doebler, Barbara Erwin, Anna Hickerson, Bruce Irvine, Denice Woyski, Ali Nadim, James D. Sterling Jan 2009

Continuous-Flow, Rapid Lysis Devices For Biodefense Nucleic Acid Diagnostic Systems, Robert W. Doebler, Barbara Erwin, Anna Hickerson, Bruce Irvine, Denice Woyski, Ali Nadim, James D. Sterling

Business and Information Technology Faculty Research & Creative Works

Two mechanical lysis devices have been developed as compact, robust components to provide rapid sample preparation for nucleic acid diagnostic systems. One such component, known as the Micro Bead-Beater™ (μBB™, BBTM, Claremont BioSolutions, Upland, CA), is a compact device that is capable of ultrarapid lysis (>90% lysis in 30 s) of micro volumes (< 80 μL) of Bacillus spores in a continuous-flow format or in a disposable single-tube format. The μBB is also capable of processing much larger volumes of solutions containing spores or vegetative cells using a continuous-flow mode. A second mechanical lysis device designed as a disposable component is the microfluidic bead blender, which uses a small electric motor to spin vanes within the bead-laden solution. DNA quantification results using dsDNA-binding fluorescence dyes and real-time PCR are presented, comparing the lysis of Bacillus subtilis spores using the μBB™ with other well-known lysis techniques. Nanoscale imaging results obtained using scanning electron microscopy and transmission electron microscopy on B. subtilis spores lyzed using the μBB™ are also presented. © 2009, Society for Laboratory Automation and Screening. All rights reserved.


Mesoscale Behavior Of An Aluminum-Manganese Dioxide-Epoxy Mixture Under Shock Loading: From Milli To Nano-Sized Aluminum Particles, Andrew Fraser Jan 2009

Mesoscale Behavior Of An Aluminum-Manganese Dioxide-Epoxy Mixture Under Shock Loading: From Milli To Nano-Sized Aluminum Particles, Andrew Fraser

Master's Theses (2009 -)

The main focus of this thesis is to explore the dynamic shock compaction of multiple component mixtures, specifically Al-MnO2-Epoxy. This will be facilitated by initially simulating the bulk dynamic response in a mesoscale configuration and then comparing these results to experimental data. The mesoscale simulations were performed in the shock code CTH. The first section will discuss the matching of experimental data to computational results. With the goal of determining the bulk shock Hugoniot, a one-dimensional flyer plate configuration was created while using a grain-geometry imported from an scanning electron microscope (SEM) micrograph of the mixture. Both the …


High Temperature Oxidation Behavior Of Nb-20mo-15si-5b-20cr Alloy, Julieta Angelica Ventura Jan 2009

High Temperature Oxidation Behavior Of Nb-20mo-15si-5b-20cr Alloy, Julieta Angelica Ventura

Open Access Theses & Dissertations

Materials for high temperature applications, such as jet engines, gas turbines and turbine blades, require a balanced combination of physical and chemical properties to withstand the aggressive environments in which they are utilized. Some of the properties required are high strength, low density, high melting point and good oxidation resistance at elevated temperatures [1-3]. For this reason, the microstructure and oxidation behavior of the Nb-20Mo-15Si-5B-20Cr alloy (at.%) has been studied as a potential candidate to replace Nickel-based alloys currently used in the aerospace industry.

Short term oxidation (STO) and long term oxidation (LTO) studies have been performed in air for …


Remote Control Of Multiple Robots: A Wireless Sensor Network And Virtual Reality Approach, Yingjun Zhu Jan 2009

Remote Control Of Multiple Robots: A Wireless Sensor Network And Virtual Reality Approach, Yingjun Zhu

Open Access Theses & Dissertations

A tele-operation system of robots based on virtual reality and WSN is established and demonstrated. Pro/E, Blender 3D and Python language are adopted to build up and carry out the virtual environment and virtual robot. Wireless Sensor Network (WSN) technology has been used to achieve the tele-operation function. The WSN enables the users to control the robots and collect the data/status from the robots as well. Robot virtual reality software has been developed and presented in the paper. The network setup and the control/communication Application Programming Interface (API) has been shown in this paper.


Low Cost Lightweight Mode Forming System For Angle Of Arrival Estimation, Mark Anthony Stewart Jan 2009

Low Cost Lightweight Mode Forming System For Angle Of Arrival Estimation, Mark Anthony Stewart

Browse all Theses and Dissertations

Current mode forming systems have high angular resolution and operate over large bandwidths. System size, complexity, and cost restrict the use of these systems to ground-based or large-airframe platforms. A spiral antenna in conjunction with mission- specific modularized planar microstrip mode formers would allow for angle of arrival estimations on smaller platforms such as a medium-sized UAV. This thesis investigates the mode forming characteristics of a planar four arm spiral antenna driven with a planar microstrip mode former designed to operate over a single personal communications band. The theoretical foundation for a closed-form angle of arrival estimation given by Penno …


A Predictive Model Of Cognitive Performance Under Acceleration Stress, Richard Andrew Mckinley Jan 2009

A Predictive Model Of Cognitive Performance Under Acceleration Stress, Richard Andrew Mckinley

Browse all Theses and Dissertations

Extreme acceleration maneuvers encountered in modern agile fighter aircraft can wreak havoc on human physiology thereby significantly influencing cognitive task performance. Increased acceleration causes a shift in local arterial blood pressure and profusion causing declines in regional cerebral oxygen saturation. As oxygen content continues to decline, activity of high order cortical tissue reduces to ensure sufficient metabolic resources are available for critical life-sustaining autonomic functions. Consequently, cognitive abilities reliant on these affected areas suffer significant performance degradations. This goal of this effort was to develop and validate a model capable of predicting human cognitive performance under acceleration stress. An Air …