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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 …


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 …


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 …


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 …


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 …


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 …


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.


Flexible Multitouch Electroluminescent Display, Michael E. Miller, John W. Harmer Dec 2011

Flexible Multitouch Electroluminescent Display, Michael E. Miller, John W. Harmer

AFIT Patents

A display device including a touch sensitive EL display having a flexible substrate; one or more power busses and one or more EL elements disposed over the flexible substrate; and a plurality of distributed chiplets arranged so that at least two chiplets are associated with each of a plurality of touch sensitive areas on the EL display and for sensing stress or strain associated with bending of the flexible substrate or the chiplet substrate to provide respective displacement signals corresponding to the touch sensitive areas; each chiplet connected to one or more of the power busses and one or more …


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 …


Windows Driver Memory Analysis: A Reverse Engineering Methodology, James S. Okolica, Gilbert L. Peterson Nov 2011

Windows Driver Memory Analysis: A Reverse Engineering Methodology, James S. Okolica, Gilbert L. Peterson

Faculty Publications

In a digital forensics examination, the capture and analysis of volatile data provides significant information on the state of the computer at the time of seizure. Memory analysis is a premier method of discovering volatile digital forensic information. While much work has been done in extracting forensic artifacts from Windows kernel structures, less focus has been paid to extracting information from Windows drivers. There are two reasons for this: (1) source code for one version of the Windows kernel (but not associated drivers) is available for educational use and (2) drivers are generally called asynchronously and contain no exported functions. …


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 …


An Empirical Analysis Of The Cascade Error Reconciliation Protocol For Quantum Key Distribution, Timothy I. Calver, Michael R. Grimaila, Jeffrey W. Humphries Oct 2011

An Empirical Analysis Of The Cascade Error Reconciliation Protocol For Quantum Key Distribution, Timothy I. Calver, Michael R. Grimaila, Jeffrey W. Humphries

Faculty Publications

Modern cryptography provides the means to securely communicate data between authorized entities by using mathematical transformations which require pre-shared cryptographic keys. The need to share key material with authorized entities in a secure, cost efficient and timely manner has driven efforts to develop new key distribution methods. A promising method is Quantum Key Distribution (QKD) which is considered to be “unconditionally secure” because it relies upon the immutable laws of quantum physics rather than computational complexity as the basis for its security. An important component of any QKD system is the error reconciliation protocol which is used to identify and …


Two-Dimensional, Time-Dependent Plasma Structures Of A Hall Effect Thruster, David Liu Sep 2011

Two-Dimensional, Time-Dependent Plasma Structures Of A Hall Effect Thruster, David Liu

Theses and Dissertations

The Hall thruster is a type of electric propulsion utilized by satellites to perform a wide variety of missions ranging from station keeping, orbital maneuvers, and even deep space propulsion. In order to accommodate the multitude of missions it also has a wide assortment of sizes and power configurations which can range from approximately an inch in diameter at 20 W to a couple of feet in diameter at 1.5 kW. Additionally, this electro-static device provides high specific impulse without the added weight penalty associated with conventional chemical thrusters. It supplies this high specific impulse by ionizing a gas such …


Increasing The Performance Of A Sliding Discharge Actuator Through The Application Of Multiple Potentials, Steven D. Seney Jr. Sep 2011

Increasing The Performance Of A Sliding Discharge Actuator Through The Application Of Multiple Potentials, Steven D. Seney Jr.

Theses and Dissertations

This work encompasses a comparison between a sliding discharge DBD actuator with grounded and AC biased sliding electrode driven at kHz frequency. The induced velocity in the bulk flow was recorded with PIV and compared for multiple potential splits between two test configurations and a baseline sliding discharge actuator over three test phases. In the first test phase, varying potential splits were examined between the primary and secondary electrode with the sliding electrode grounded. The potential splits induced a thicker induced jet than the baseline case with similar peak velocities on the order of 1.25 m/s at the 61 mm …


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 …


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 …


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 …


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 …


Non-Adiabatic Atomic Transitions: Computational Cross Section Calculations Of Alkali Metal-Noble Gas Collisions, Charlton D. Lewis Ii Sep 2011

Non-Adiabatic Atomic Transitions: Computational Cross Section Calculations Of Alkali Metal-Noble Gas Collisions, Charlton D. Lewis Ii

Theses and Dissertations

Diode Pumped Alkali Lasers operate by exciting a gaseous cell of alkali metal to its P3/2 excited energy state. A noble gas, present in the cell, collisionally de-excites the alkali metal to its P1/2 state. The alkali atoms then relax to their S1/2 ground state by emitting photons. The non-radiative de-excitation due to inert gas atoms represents an interesting juncture for DPALs operation. This process must be faster than the radiative relaxation back to the S1/2 state for lasing to occur. The rate of non-radiative de-excitation is related to the collisional cross section and the cross …


Effect Of Storm Enhanced Densities On Geo-Location Accuracy Over Conus, Lindon H. Steadman Sep 2011

Effect Of Storm Enhanced Densities On Geo-Location Accuracy Over Conus, Lindon H. Steadman

Theses and Dissertations

Storm enhanced densities (SEDs) are ionospheric plasma enhancements that disrupt radio communications in the near-Earth space environment, degrading the Global Positioning System (GPS) and other key technologies. Accurate GPS/total electron content (TEC) correction maps produced by ionosphere models can mitigate degradations from SEDs. An artificial SED was created and ingested via slant TEC measurements into the Global Assimilation of Ionospheric Measurements Gauss-Markov Kalman Filter Model to determine how many ground GPS receivers are needed to produce reliable GPS/TEC correction maps over the continental United States during geomagnetic storming. It was found that 110 well-positioned GPS receivers produced the best overall …


Analysis Of Transient Electromagnetic Scattering From An Overfilled Cavity Embedded In An Impedance Ground Plane, Robert S. Callihan Sep 2011

Analysis Of Transient Electromagnetic Scattering From An Overfilled Cavity Embedded In An Impedance Ground Plane, Robert S. Callihan

Theses and Dissertations

We consider the transient, or time-domain, scattering problem of a two-dimensional overfilled cavity embedded in an impedance ground plane. This problem is a significant advancement from previous work where more simplified boundary conditions were used, which can limit the number of applications. This research supports a wide range of military applications such as the study of cavity-like structures on aircraft and vehicles. More importantly, this research helps detect the biggest threat on today's battlefield: improvised explosive devices. An important step in solving the problem is introducing an artificial boundary condition on a semicircle enclosing the cavity; this couples the fields …


Identification And Classification Of Player Types In Massive Multiplayer Online Games Using Avatar Behavior, Earl M. Bednar Sep 2011

Identification And Classification Of Player Types In Massive Multiplayer Online Games Using Avatar Behavior, Earl M. Bednar

Theses and Dissertations

The purpose of our research is to develop an improved methodology for classifying players (identifying deviant players such as terrorists) through multivariate analysis of data from avatar characteristics and behaviors in massive multiplayer online games (MMOGs). To build our classification models, we developed three significant enhancements to the standard Generalized Regression Neural Networks (GRNN) modeling method. The first enhancement is a feature selection technique based on GRNNs, allowing us to tailor our feature set to be best modeled by GRNNs. The second enhancement is a hybrid GRNN which allows each feature to be modeled by a GRNN tailored to its …


Modeling And Analysis Of High Energy Laser Weapon System Performance In Varying Atmospheric Conditions, Megan P. Melin Sep 2011

Modeling And Analysis Of High Energy Laser Weapon System Performance In Varying Atmospheric Conditions, Megan P. Melin

Theses and Dissertations

This thesis addresses two primary concerns relating to Directed Energy (DE) models and tests: need for more use of Design of Experiment (DOE) in structuring DE models and tests, and lack of modeling atmospheric variability in High Energy Laser (HEL) weapon system propagation models and tests. To address these concerns we use a DOE factorial design to capture main, interaction, and non-linear effects between modeled weapon design and environmental factors in a well defined simulated Air-to-Ground HEL engagement scenario. The scenario modeled considers a B1-B aircraft in the 2022 timeframe equipped with an HEL weapon, irradiating a ground target from …


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 …