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Air Force Institute of Technology

Theses/Dissertations

2011

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Exploitation Of Unintentional Information Leakage From Integrated Circuits, William E. Cobb Dec 2011

Exploitation Of Unintentional Information Leakage From Integrated Circuits, William E. Cobb

Theses and Dissertations

Unintentional electromagnetic emissions are used to recognize or verify the identity of a unique integrated circuit (IC) based on fabrication process-induced variations in a manner analogous to biometric human identification. The effectiveness of the technique is demonstrated through an extensive empirical study, with results presented indicating correct device identification success rates of greater than 99:5%, and average verification equal error rates (EERs) of less than 0:05% for 40 near-identical devices. The proposed approach is suitable for security applications involving commodity commercial ICs, with substantial cost and scalability advantages over existing approaches. A systematic leakage mapping methodology is also proposed to …


Investigation Of Gallium Nitride Transistor Reliability Through Accelerated Life Testing And Modeling, Bradley D. Christiansen Dec 2011

Investigation Of Gallium Nitride Transistor Reliability Through Accelerated Life Testing And Modeling, Bradley D. Christiansen

Theses and Dissertations

Gallium nitride high electron mobility transistors are attractive to the DoD for their ability to operate at high frequencies, voltages, temperatures, and power. Yet, there are concerns about the reliability of these devices. Various degradation mechanisms and their causes are proposed in the literature. A variety of reliability tests were conducted to understand these mechanisms and causes. A multi-stressor experiment revealed different failure mechanisms than are in the literature. In particular, the devices tested at high voltage in the OFF state did not degrade significantly as suggested by others' reports. The validity of temperature-accelerated life testing when applied to GaN …


Electroluminescence Studies On Longwavelength Indium Arsenide Quantum Dot Microcavities Grown On Gallium Arsenide, John C. Ramsey Dec 2011

Electroluminescence Studies On Longwavelength Indium Arsenide Quantum Dot Microcavities Grown On Gallium Arsenide, John C. Ramsey

Theses and Dissertations

A comprehensive study of the electroluminescence of four GaAs/AlGaAs microcavity devices with InAs/GaInAs quantum dot active regions emitting near 1.3 µm was conducted. The four molecular beam epitaxial grown samples with AlAs oxide aperture confinement layers were fabricated, characterized, and optically modeled. Optical power transmission of the samples was modeled using Matlab and compared with measured transmission data. Resonant cavity light emitting diodes (RCLEDs) and three vertical cavity surface emitting laser (VCSEL) samples were fabricated and electro-optically characterized over a range of injection currents and temperatures. Devices achieved continuous wave room temperature lasing at 1.28 µm with an output power …


Linear-Quadratic Control Of A Mems Micromirror Using Kalman Filtering, Jamie P. Schnapp Dec 2011

Linear-Quadratic Control Of A Mems Micromirror Using Kalman Filtering, Jamie P. Schnapp

Theses and Dissertations

The deflection limitations of electrostatic flexure-beam actuators are well known. Specifically, as the beam is actuated and the gap traversed, the restoring force necessary for equilibrium increases proportionally with the displacement to first order, while the electrostatic actuating force increases with the inverse square of the gap. Equilibrium, and thus stable open-loop voltage control, ceases at one-third the total gap distance, leading to actuator snap-in. A Kalman Filter is designed with an appropriately complex state dynamics model to accurately estimate actuator deflection given voltage input and capacitance measurements, which are then used by a Linear Quadratic controller to generate a …


Kinetics Of The Electrical Discharge Pumped Oxygen-Iodine Laser, Matthew A. Lange Dec 2011

Kinetics Of The Electrical Discharge Pumped Oxygen-Iodine Laser, Matthew A. Lange

Theses and Dissertations

A systematic study of microwave discharges at 2.45 GHz has been performed through the pressure range of sustainable electric discharges in pure oxygen flows of 2 to 10 Torr. A corresponding study of 13.56 MHz has also been performed at pressures of 2, 4, and 7 Torr. Optical emissions from O2(a 1Δ), O2(b 1Σ), and O-atoms have been measured from the center of a μ-wave discharge. Discharge residence times from 0.1 to 5 ms have been reported. The O2(b 1Σ) emissions, with a spectral resolution of 0.01 nm, have been used to measure the temperature of the gas, which typically …


A Method For Measuring Programmatic Dependency And Interdependency Between Dod Acquisition Programs, Matthew B. Christensen Dec 2011

A Method For Measuring Programmatic Dependency And Interdependency Between Dod Acquisition Programs, Matthew B. Christensen

Theses and Dissertations

There is currently no accepted method for quantitative measurement of acquisition program interdependency. While some methods exist for measuring dependency or interdependency at the component or system level, these methods do not translate well to program interdependency measurement. The objective of this thesis is to provide a model for measuring acquisition program interdependency accurately and quantitatively. The model presented in this thesis uses four Interdependency Factors to identify dependency relationships between programs. Specific Interdependency Levels are then used to measure the strengths of those dependencies. The model also accounts for measurement of dependencies upon programs that are not directly connected, …


Link Performance Analysis For A Proposed Future Architecture Of The Air Force Satellite Control Network, Eric W. Nelson Dec 2011

Link Performance Analysis For A Proposed Future Architecture Of The Air Force Satellite Control Network, Eric W. Nelson

Theses and Dissertations

The Air Force Satellite Control Network (AFSCN) is a worldwide network of ground stations that support a wide variety of users from the National Aeronautics and Space Administration (NASA) to the National Reconnaissance Office (NRO). The network performs tracking, telemetry, and commanding (TT&C) for these varied users. Users, located at Satellite Operations Centers (SOC), must compete for time on the AFSCN. This thesis demonstrates how to predict satellite link performance, specifically by users of the AFSCN. It will also demonstrate how users might use this capability to save spacecraft power. A tool was created called the AFSCN Link Predictor (LP) …


Rapid Development: A Content Analysis Comparison Of Literature And Purposive Sampling Of Afrl Rapid Reaction Projects, Andrew R. Smith Dec 2011

Rapid Development: A Content Analysis Comparison Of Literature And Purposive Sampling Of Afrl Rapid Reaction Projects, Andrew R. Smith

Theses and Dissertations

In the current environment of military operations requesting faster delivery schedules to counter insurgent tactics, the engineering team often searches for how to quickly deliver the 80% solution, typically in 6-12 months. These are labeled rapid development projects. A content analysis of best practices in commercial product development literature, where time to market is often a driving factor, was accomplished showing varying emphasis of systems engineering technical and technical management processes. Technical Planning, Stakeholders Requirements Development, and Architecture Design were identified as important processes. This analysis confirms preconceived notions of plan upfront and early by emphasizing the SE processes of …


Characterization And Discrimination Of Large Caliber Gun Blast And Flash Signatures, Bryan J. Steward Dec 2011

Characterization And Discrimination Of Large Caliber Gun Blast And Flash Signatures, Bryan J. Steward

Theses and Dissertations

Two hundred and one firings of three 152 mm howitzer munitions were observed to characterize firing signatures of a large caliber gun. Muzzle blast expansion was observed with high-speed (1600 Hz) optical imagery. The trajectory of the blast front was well approximated by a modified point-blast model described by constant rate of energy deposition. Visible and near-infrared (450 - 850 nm) spectra of secondary combustion were acquired at 0.75 nm spectral resolution and depict strong contaminant emissions including Li, Na, K, Cu, and Ca. The O2 (X-b) absorption band is evident in the blue wing of the potassium D lines …


Development Of Photographic Dynamic Measurements Applicable To Evaluation Of Flapping Wing Micro Air Vehicles, Jeremy C. Murray Dec 2011

Development Of Photographic Dynamic Measurements Applicable To Evaluation Of Flapping Wing Micro Air Vehicles, Jeremy C. Murray

Theses and Dissertations

Developments in the area of flapping wing micro air vehicles (FWMAVs) of a small size and with limited range. This has lead to a great deal of interest in biomimetric designs based on flapping wing flyers, including the North American Hawkmoth (Manduca Sexta). By utilizing high speed photography and photogrammetry the dynamic flapping of the wing can be characterized for comparison with mathematical models, namely computational fluid dynamics (CFD) and finite element analysis (FEA).To successfully utilize high speed image capture, a method of successfully digitizing many data points in a short period of time needs to be developed. The effort …


The Use Of Various Failure Criteria As Applied To High Speed Wear, David A. Huber Dec 2011

The Use Of Various Failure Criteria As Applied To High Speed Wear, David A. Huber

Theses and Dissertations

This research has been aimed at developing methods to predict mechanical wear of sliding bodies at high velocities. Specifically, wear of test sled slippers at the Holloman High Speed Test Track at Holloman AFB, NM, is being considered. Developing a numerical model to represent the velocity range achieved at the test track is infeasible, so numerical modeling techniques must be adopted. Previous research has made use of finite element codes to simulate the high velocity sliding event. However, the extreme velocities at the test track can create numerical errors in the finite element codes. To avoid the numerical errors, an …


Scramjet Isolator Modeling And Control, John R. Hutzel Dec 2011

Scramjet Isolator Modeling And Control, John R. Hutzel

Theses and Dissertations

The scramjet isolator is a duct in which pressure increases from the inlet to the combustor via a shock train. The shock train leading edge (LE) location must be controlled in an operational scramjet. A LE location measurement algorithm, dynamic model, and control algorithm were developed and validated with 500 frame per second (FPS) shadowgraph images in this research. The test apparatus consisted of a direct connect cold-flow high-speed wind tunnel with an adjustable ramp mounted in the tunnel floor. Ramp adjustments changed the tunnel cross-sectional area which changed the tunnel back pressure and LE location. Wall-mounted pressure transducers and …


Coupled Radiation-Gasdynamic Solution Method For Hypersonic Shock Layers In Thermochemical Nonequilibrium, Christopher L. Martin Jr. Dec 2011

Coupled Radiation-Gasdynamic Solution Method For Hypersonic Shock Layers In Thermochemical Nonequilibrium, Christopher L. Martin Jr.

Theses and Dissertations

The purpose of this research was to develop a highly accurate computational method for calculating the nonequilibrium radiative heat transfer within reentry shock layers. The nonequilibrium state of the flowfield was solved using the multispecies multitemperature nonequilibrium flow solver NH7AIR which is capable of separately tracking the vibrational energy of each diatomic species and the energy of the free electrons. The calculation of radiative heat transfer was performed by utilizing the detailed line-by-line spectral radiation solver SPRADIAN. Two radiative transport schemes were implemented in this coupled code. The first scheme was the standard tangent slab solution method. The second scheme …


Background-Oriented Schlieren Pattern Optimization, Jeffery E. Hartberger Dec 2011

Background-Oriented Schlieren Pattern Optimization, Jeffery E. Hartberger

Theses and Dissertations

This paper describes a test series to investigate background patterns used for the Background-Oriented Schlieren field density measurement technique. Several varying background patterns were substituted under similar fluid density conditions to visualize and isolate the effects of patterns in the background images. A qualitative comparison was completed of the flow visualization results of each background pattern to categorize background conditions that improved the flow visualization image. Changes in background patterns revealed significant changes in flow visualization. Pattern contrast, spacing and sizing all played large parts in the quality of the visual density gradient imaging during the test series.


Optimized Hyperspectral Imagery Anomaly Detection Through Robust Parameter Design, Francis M. Mindrup Oct 2011

Optimized Hyperspectral Imagery Anomaly Detection Through Robust Parameter Design, Francis M. Mindrup

Theses and Dissertations

Anomaly detection algorithms for hyperspectral imagery (HSI) are an important first step in the analysis chain which can reduce the overall amount of data to be processed. The actual amount of data reduced depends greatly on the accuracy of the anomaly detection algorithm implemented. Most, if not all, anomaly detection algorithms require a user to identify some initial parameters. These parameters (or controls) affect overall algorithm performance. Regardless of the anomaly detector being utilized, algorithm performance is often negatively impacted by uncontrollable noise factors which introduce additional variance into the process. In the case of HSI, the noise variables are …


Evaluation Of Nanocomposites For Shielding Electromagnetic Interference, Kenneth Y. Chong Sep 2011

Evaluation Of Nanocomposites For Shielding Electromagnetic Interference, Kenneth Y. Chong

Theses and Dissertations

Numerous efforts are ongoing to research and develop nanocomposite materials for space applications. Current composite spacecraft materials are nonconductive and require costly shielding materials to be applied in order to protect spacecraft from the harmful effects caused by electromagnetic interference (EMI), which is a by-product of exposure to the space environment. Conductive fillers (nanofibers) are being employed in composites to produce nanocomposites to reduce the dry weight of space vehicles while providing sufficient protection against EMI. This eliminates the need to apply secondary shielding materials to spacecraft. This thesis studied a nanocomposite consisting of Cycom 5575-2 glass with multi-walled carbon …


An Empirical Analysis Of The Cascade Secret Key Reconciliation Protocol For Quantum Key Distribution, Timothy I. Calver Sep 2011

An Empirical Analysis Of The Cascade Secret Key Reconciliation Protocol For Quantum Key Distribution, Timothy I. Calver

Theses and Dissertations

The need to share key material with authorized entities in a secure, efficient and timely manner has driven efforts to develop new key distribution methods. The most promising method is Quantum Key Distribution (QKD) and is considered to be “unconditionally secure” because it relies upon the immutable laws of quantum physics rather than computational complexity. Unfortunately, the nonidealities present in actual implementations of QKD systems also result in errors manifested in the quantum data channel. As a consequence, an important component of any QKD system is the error reconciliation protocol which is used to identify and correct inconsistencies in the …


Major Cost Drivers Of Motor Vehicle Crashes Involving Air Force Military Personnel And The Influence Of The Military Environment, Ilias Kesisiklis Sep 2011

Major Cost Drivers Of Motor Vehicle Crashes Involving Air Force Military Personnel And The Influence Of The Military Environment, Ilias Kesisiklis

Theses and Dissertations

Motor vehicle crashes (MVCs) involving USAF military personnel when off duty/off base are a critical concern for the Department of Defense (DoD), due to potential impact on mission readiness. In addition, the cost of MVCs places excessive financial burden on the USAF budget, apart from productivity loss and negative emotional consequences on the victims. In particular, total injury cost was $ 356M, based on 2010 CY dollars. Determining the underlying factors leading to MVCs is crucial to establishing effective preventive measures to mitigate the negative consequences of MVCs.
This thesis applied categorical data and multiple regression analyses on (AFSC) historical …


Distributed Spacing Stochastic Feature Selection And Its Application To Textile Classification, Jeffrey D. Clark Sep 2011

Distributed Spacing Stochastic Feature Selection And Its Application To Textile Classification, Jeffrey D. Clark

Theses and Dissertations

Many situations require the need to quickly and accurately locate dismounted individuals in a variety of environments. In conjunction with other dismount detection techniques, being able to detect and classify clothing (textiles) provides a more comprehensive and complete dismount characterization capability. Because textile classification depends on distinguishing between different material types, hyperspectral data, which consists of several hundred spectral channels sampled from a continuous electromagnetic spectrum, is used as a data source. However, a hyperspectral image generates vast amounts of information and can be computationally intractable to analyze. A primary means to reduce the computational complexity is to use feature …


A Novel Malware Target Recognition Architecture For Enhanced Cyberspace Situation Awareness, Thomas E. Dube Sep 2011

A Novel Malware Target Recognition Architecture For Enhanced Cyberspace Situation Awareness, Thomas E. Dube

Theses and Dissertations

The rapid transition of critical business processes to computer networks potentially exposes organizations to digital theft or corruption by advanced competitors. One tool used for these tasks is malware, because it circumvents legitimate authentication mechanisms. Malware is an epidemic problem for organizations of all types. This research proposes and evaluates a novel Malware Target Recognition (MaTR) architecture for malware detection and identification of propagation methods and payloads to enhance situation awareness in tactical scenarios using non-instruction-based, static heuristic features. MaTR achieves a 99.92% detection accuracy on known malware with false positive and false negative rates of 8.73e-4 and 8.03e-4 respectively. …


Phase History Decomposition For Efficient Scatterer Classification In Sar Imagery, Dane F. Fuller Sep 2011

Phase History Decomposition For Efficient Scatterer Classification In Sar Imagery, Dane F. Fuller

Theses and Dissertations

A new theory and algorithm for scatterer classification in SAR imagery is presented. The automated classification process is operationally efficient compared to existing image segmentation methods requiring human supervision. The algorithm reconstructs coarse resolution subimages from subdomains of the SAR phase history. It analyzes local peaks in the subimages to determine locations and geometric shapes of scatterers in the scene. Scatterer locations are indicated by the presence of a stable peak in all subimages for a given subaperture, while scatterer shapes are indicated by changes in pixel intensity. A new multi-peak model is developed from physical models of electromagnetic scattering …


Using Reputation Based Trust To Overcome Malfunctions And Malicious Failures In Electric Power Protection Systems, Jose E. Fadul Sep 2011

Using Reputation Based Trust To Overcome Malfunctions And Malicious Failures In Electric Power Protection Systems, Jose E. Fadul

Theses and Dissertations

This dissertation advocates the use of reputation-based trust in conjunction with a trust management framework based on network flow techniques to form a trust management toolkit (TMT) for the defense of future Smart Grid enabled electric power grid from both malicious and non-malicious malfunctions. Increases in energy demand have prompted the implementation of Smart Grid technologies within the power grid. Smart Grid technologies enable Internet based communication capabilities within the power grid, but also increase the grid's vulnerability to cyber attacks. The benefits of TMT augmented electric power protection systems include: improved response times, added resilience to malicious and non-malicious …


Critical Information Technology On Fpgas Through Unique Device Specific Keys, Miles E. Mcgee Sep 2011

Critical Information Technology On Fpgas Through Unique Device Specific Keys, Miles E. Mcgee

Theses and Dissertations

Field Programmable Gate Arrays (FPGAs) are being used for military and other sensitive applications, the threat of an adversary attacking these devices is an ever present danger. While having the ability to be reconfigured is helpful for development, it also poses the risk of its hardware design being cloned. Static random access memory (SRAM) FPGA's are the most common type of FPGA used in industry. Every time an SRAM-FPGA is powered up, its configuration must be downloaded. If an adversary is able to obtain that configuration, they can clone sensitive designs to other FPGAs. A technique that can be used …


Detecting Man-In-The-Middle Attacks Against Transport Layer Security Connections With Timing Analysis, Lauren M. Wagoner Sep 2011

Detecting Man-In-The-Middle Attacks Against Transport Layer Security Connections With Timing Analysis, Lauren M. Wagoner

Theses and Dissertations

The Transport Layer Security (TLS) protocol is a vital component to the protection of data as it traverses across networks. From e-commerce websites to Virtual Private Networks (VPNs), TLS protects massive amounts of private information, and protecting this data from Man-in-the-Middle (MitM) attacks is imperative to keeping the information secure. This thesis illustrates how an attacker can successfully perform a MitM attack against a TLS connection without alerting the user to his activities. By deceiving the client machine into using a false certificate, an attacker takes away the only active defense mechanism a user has against a MitM. The goal …


Integrated Approach To Free Space Optical Communications In Strong Turbulence, Jason A. Tellez Sep 2011

Integrated Approach To Free Space Optical Communications In Strong Turbulence, Jason A. Tellez

Theses and Dissertations

The propagation of a free space optical communication signal through atmospheric turbulence experiences random fluctuations in intensity, including signal fades which negatively impact the communications link performance. This research develops an analytical probability density function (PDF) to model the best case scenario of using multiple independent beams to reduce the intensity fluctuations. The PDF was further developed to account for partially correlated beams, such as would be experienced by beams having finite separation. The PDF was validated with results obtained from digital simulations as well as lab experiments. The research showed that as the number of transmitted beams increases the …


Modeling Self-Referencing Interferometers With Extended Beacons And Strong Turbulence, Daniel J. Wheeler Sep 2011

Modeling Self-Referencing Interferometers With Extended Beacons And Strong Turbulence, Daniel J. Wheeler

Theses and Dissertations

The overall purpose of this research was to better understand the performance of a self-referencing interferometer (SRI) when used with extended beacons in strong atmospheric turbulence. It was performed by assuming the extended beacon could be modeled as a Gaussian Schell-model beam, then analyzing the effect of propagating this beam through strong atmospheric turbulence. Since the operation of an SRI requires coupling this light into a single-mode optical fiber, analytic expressions of the mean and normalized variance of the coupling efficiency were derived. An improved noise model for the SRI was then developed that included all potential noise sources such …


Verification Of Global Assimilation Of Ionospheric Measurements Gauss Markov (Gaim-Gm) Model Forecast Accuracy, Paul H. Domm Sep 2011

Verification Of Global Assimilation Of Ionospheric Measurements Gauss Markov (Gaim-Gm) Model Forecast Accuracy, Paul H. Domm

Theses and Dissertations

GAIM-GM is an operational Kalman filter data assimilation model of the ionosphere that can assimilate data from GPS total electron content (TEC), ionosonde electron density profiles, and satellite based in situ electron densities. The Air Force Weather Agency (AFWA) uses GAIM-GM to specify and forecast the ionosphere. An in depth investigation into the accuracy of these forecasts has not been completed. GAIM-GM output obtained from four cases run from combinations of geomagnetic and solar activity was used to determine GAIM-GM forecast accuracy. Forecast accuracy was determined through the use of a skill score as well as other statistical tools to …


Assessment Of The Effects Of Plasma Bubbles On Gaim-Gm, Kenneth R. Fenton Sep 2011

Assessment Of The Effects Of Plasma Bubbles On Gaim-Gm, Kenneth R. Fenton

Theses and Dissertations

Plasma bubbles are regions of depleted plasma density generated in the post-sunset equatorial region of the ionosphere. Bubbles significantly affect total electron count (TEC) and consequently alter communication and navigation capabilities. Here, the Global Assimilation of Ionospheric Measurements Gauss-Markov (GAIM-GM) model is studied in order to assess its capability to accurately model equatorial plasma bubbles. GAIM-GM uses the Ionospheric Forecast Model (IFM) as a background state modified through the application of a Kalman Filter to incorporate ionospheric observations such as Global Positioning System (GPS) total electron content (TEC) values. GPS TEC values representative of plasma bubble conditions are modeled and …


The Effects Of Rare Earth Doping On Gallium Nitride Thin Films, Stephen R. Mchale Sep 2011

The Effects Of Rare Earth Doping On Gallium Nitride Thin Films, Stephen R. Mchale

Theses and Dissertations

The thermal neutron capture cross section of the rare earth (RE) metal isotope Gd-157 is the largest of all known natural elements, which distinguishes the material as a logical candidate for neutron detection. To address an incomplete understanding of rare earth doped Gallium Nitride (GaN) materials, investigations of the surface electronic structure and interface properties of GaN thin films doped with rare earths (Yb, Er, Gd) were undertaken. Lattice ion occupation, bonding, rare earth 4f occupation, and gold Schottky barrier formation were examined using synchrotron photoemission spectroscopy. Measured Debye temperatures indicate substitutional occupation of Ga sites by RE ions. The …


Source Normalization Constants For Ground Distributed Fallout Fields, Justin M. Smith Sep 2011

Source Normalization Constants For Ground Distributed Fallout Fields, Justin M. Smith

Theses and Dissertations

Five assumptions regarding a first order model developed to calculate dose rate at a detector above a fallout field are analyzed. The omission of scattering is relaxed by the method of successive scatters resulting in a build up factor of 1.1. The use of a single average photon energy to represent a fallout distribution is analyzed using the Oak Ridge National Laboratory Isotope Generator (ORIGEN) Fallout Analysis Tool. An average photon energy of 0.81MeV is calculated and shown to be an accurate approximation of the fallout field energy distribution. A Gaussian distribution is used to calculate the minimal impact of …