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Air Force Institute of Technology

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Full-Text Articles in Physical Sciences and Mathematics

Application Of An Imaging Fourier-Transform Spectrometer For The Means Of Combustion Diagnostics, Michael R. Rhoby Jun 2012

Application Of An Imaging Fourier-Transform Spectrometer For The Means Of Combustion Diagnostics, Michael R. Rhoby

Theses and Dissertations

A passive remote sensing technique for accurately monitoring the combustion efficiency of petrochemical flares is greatly desired. A Phase II DOE-funded SBIR lead by Spectral Sciences, Inc. is underway to develop such a method. This paper presents an overview of the progress of AFIT's contribution. A Telops Hyper-Cam Mid-wave infrared imaging Fourier-transform spectrometer is used to examine a flame produced by a Hencken burner. Ethylene fuel was burned at four different equivalency ratios φ = 0:80; 0:91; 1:0 and 1:25. Presented is qualitative spectrally-resolved visualization of a Hencken burner flame and the spatial distribution of combustion by-products. The flame spectra …

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Resource Provisioning In Large-Scale Self-Organizing Distributed Systems, M. Brent Reynolds Jun 2012

Resource Provisioning In Large-Scale Self-Organizing Distributed Systems, M. Brent Reynolds

Theses and Dissertations

This dissertation researches the mathematical translation of resource provisioning policy into mathematical terms and parameters to solve the on-line service placement problem. A norm called the Provisioning Norm is introduced. Theorems presented in the work show the Provisioning Norm utility function and greedy, random, local search effectively and efficiently solve the on-line problem. Caching of placements is shown to reduce the cost of change but does not improve response time performance. The use of feedback control theory is shown to be effective at significantly improving performance but increases the cost of change. The theoretical results are verified using a decentralized, …

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Implementation Of Branch-Point-Tolerant Wavefront Reconstructor For Strong Turbulence Compensation, Michael J. Steinbock Jun 2012

Implementation Of Branch-Point-Tolerant Wavefront Reconstructor For Strong Turbulence Compensation, Michael J. Steinbock

Theses and Dissertations

Branch points arise in optical transmissions due to strong atmospheric turbulence, long propagation paths, or a combination of both. Unfortunately, these conditions are very often present in desired operational scenarios for laser weapon systems, optical communication, and covert imaging, which suffer greatly when traditional adaptive optics systems either cannot sense branch points or implement non-optimal methods for sensing and correcting branch points. Previous research by Pellizzari presented a thorough analysis of various novel branch point tolerant reconstructors in the absence of noise. In this research a realistic model of the Air Force Institute of Technology's adaptive optics system is developed …

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The White-Hat Bot: A Novel Botnet Defense Strategy, Tyrone C. Gubler Jun 2012

The White-Hat Bot: A Novel Botnet Defense Strategy, Tyrone C. Gubler

Theses and Dissertations

Botnets are a threat to computer systems and users around the world. Botmasters can range from annoying spam email propagators to nefarious criminals. These criminals attempt to take down networks or web servers through distributed denial-of-service attacks, to steal corporate secrets, or to launder money from individuals or corporations. As the number and severity of successful botnet attacks rise, computer security experts need to develop better early-detection and removal techniques to protect computer networks and individual computer users from these very real threats. I will define botnets and describe some of their common purposes and current uses. Next, I will …

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Short Message Service (Sms) Command And Control (C2) Awareness In Android-Based Smartphones Using Kernel-Level Auditing, Robert J. Olipane Jun 2012

Short Message Service (Sms) Command And Control (C2) Awareness In Android-Based Smartphones Using Kernel-Level Auditing, Robert J. Olipane

Theses and Dissertations

This thesis addresses the emerging threat of botnets in the smartphone domain and focuses on the Android platform and botnets using short message service (SMS) as the command and control (C2) channel. With any botnet, C2 is the most important component contributing to its overall resilience, stealthiness, and effectiveness. This thesis develops a passive host-based approach for identifying covert SMS traffic and providing awareness to the user. Modifying the kernel and implementing this awareness mechanism is achieved by developing and inserting a loadable kernel module that logs all inbound SMS messages as they are sent from the baseband radio to …

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Quest Hierarchy For Hyperspectral Face Recognition, David M. Ryer, Trevor J. Bihl, Kenneth W. Bauer Jr., Steven K. Rogers May 2012

Quest Hierarchy For Hyperspectral Face Recognition, David M. Ryer, Trevor J. Bihl, Kenneth W. Bauer Jr., Steven K. Rogers

Faculty Publications

A qualia exploitation of sensor technology (QUEST) motivated architecture using algorithm fusion and adaptive feedback loops for face recognition for hyperspectral imagery (HSI) is presented. QUEST seeks to develop a general purpose computational intelligence system that captures the beneficial engineering aspects of qualia-based solutions. Qualia-based approaches are constructed from subjective representations and have the ability to detect, distinguish, and characterize entities in the environment Adaptive feedback loops are implemented that enhance performance by reducing candidate subjects in the gallery and by injecting additional probe images during the matching process. The architecture presented provides a framework for exploring more advanced integration …

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Low-Loss Meta-Atom For Improved Resonance Response, Derrick Langley, Ronald Coutu Jr., Peter J. Collins Mar 2012

Low-Loss Meta-Atom For Improved Resonance Response, Derrick Langley, Ronald Coutu Jr., Peter J. Collins

Faculty Publications

Measurements of a meta-atom integrated with a low noise amplifier into the split-ring resonator are presented. A comparison is made between baseline meta-atoms and one integrated with a GaAs low noise amplifier. S-parameter measurements in a RF strip-line show the resonant frequency location. The resonance null is more prominent for the integrated meta-atom. Biasing the low noise amplifier from 0 to 7 VDC showed that the resonant null improved with biasing voltage. As the biasing voltage increases, the transmission null reduced from -11.82 to -23.21 dB for biases from 0 to 7 VDC at resonant frequency.

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Using Predictive Analytics To Detect Major Problems In Department Of Defense Acquisition Programs, Austin W. Dowling Mar 2012

Using Predictive Analytics To Detect Major Problems In Department Of Defense Acquisition Programs, Austin W. Dowling

Theses and Dissertations

This research provides program analysts and Department of Defense (DoD) leadership with an approach to identify problems in real-time for acquisition contracts. Specifically, we develop optimization algorithms to detect unusual changes in acquisition programs’ Earned Value data streams. The research is focused on three questions. First, can we predict the contractor provided estimate at complete (EAC)? Second, can we use those predictions to develop an algorithm to determine if a problem will occur in an acquisition program or subprogram? Lastly, can we provide the probability of a problem occurring within a given timeframe? We find three of our models establish …

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M + Ng Potential Energy Curves Including Spin-Orbit Coupling For M = K, Rb, Cs And Ng = He, Ne, Ar, Larry Aaron Blank, David E. Weeks, Gary S. Kedziora Mar 2012

M + Ng Potential Energy Curves Including Spin-Orbit Coupling For M = K, Rb, Cs And Ng = He, Ne, Ar, Larry Aaron Blank, David E. Weeks, Gary S. Kedziora

Faculty Publications

X2Σ+1/2 ⁠, A2Π1/2, A2Π3/2, and B2Σ+1/2 potential energy curves and associated dipole matrix elements are computed for M + Ng at the spin-orbit multi-reference configuration interaction level, where M = K, Rb, Cs and Ng = He, Ne, Ar. Dissociation energies and equilibrium positions for all minima are identified and corresponding vibrational energy levels are computed. Difference potentials are used together with the quasistatic approximation to estimate the position of satellite peaks of collisionally broadened D2 lines. The comparison of potential energy curves for …

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Remote Sensing Phase Fluorimetry Using Mercury Vapor Lamp, Matthew J. Bohn, Michael A. Lundin Mar 2012

Remote Sensing Phase Fluorimetry Using Mercury Vapor Lamp, Matthew J. Bohn, Michael A. Lundin

AFIT Patents

An efficient and portable method for remote detection of a target mineral material through frequency domain fluorimetry, a detection technique that measures the time lag between absorption and emission of photons, thereby determining the lifetime of said target mineral material. As claimed and disclosed in the present invention, mercury vapor lamps, a common source of industrial facility lighting, emit radiation that overlaps the UV/blue absorption spectrum of many fluorophores and may be used as an efficient and portable excitation source for remote frequency domain fluorimetry.

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Spatial And Spectral Performance Of A Chromotomosynthetic Hyperspectral Imaging System, Randall L. Bostick, Glen P. Perram Mar 2012

Spatial And Spectral Performance Of A Chromotomosynthetic Hyperspectral Imaging System, Randall L. Bostick, Glen P. Perram

Faculty Publications

The spatial and spectral resolutions achievable by a prototype rotating prism chromotomosynthetic imaging (CTI) system operating in the visible spectrum are described. The instrument creates hyperspectral imagery by collecting a set of 2D images with each spectrally projected at a different rotation angle of the prism. Mathematical reconstruction techniques that have been well tested in the field of medical physics are used to reconstruct the data to produce the 3D hyperspectral image. The instrument operates with a 100 mm focusing lens in the spectral range of 400–900 nm with a field of view of 71.6 mrad and angular resolution of …

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Empirical Analysis Of Optical Attenuator Performance In Quantum Key Distribution Systems Using A Particle Model, Thomas C. Adams Mar 2012

Empirical Analysis Of Optical Attenuator Performance In Quantum Key Distribution Systems Using A Particle Model, Thomas C. Adams

Theses and Dissertations

Quantum key distribution networks currently represent an active area of development and software modeling to address the security of future communications. One of the components used in quantum key distribution implementations is an optical attenuator. Its role in the system is necessary to reach the single photon per bit necessary to maintain theoretically perfect secrecy. How the photon pulse is modeled has a significant impact on the accuracy and performance of quantum channel components like the optical attenuator. Classical physics describe light using Maxwell's wave equations for electromagnetism. Quantum physics has demonstrated light also behaves as discrete particles referred to …

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Evaluation Of Traditional Security Solutions In The Scada Environment, Robert D. Larkin Mar 2012

Evaluation Of Traditional Security Solutions In The Scada Environment, Robert D. Larkin

Theses and Dissertations

Supervisory Control and Data Acquisition (SCADA) systems control and monitor the electric power grid, water treatment facilities, oil and gas pipelines, railways, and other Critical Infrastructure (CI). In recent years, organizations that own and operate these systems have increasingly interconnected them with their enterprise network to take advantage of cost savings and operational benefits. This trend, however, has introduced myriad vulnerabilities associated with the networking environment. As a result, the once isolated systems are now susceptible to a wide range of threats that previously did not exist. To help address the associated risks, security professionals seek to incorporate mitigation solutions …

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Incorporating Externalities And Uncertainty Into Life-Cycle Cost Analysis, Alec C. Danaher Mar 2012

Incorporating Externalities And Uncertainty Into Life-Cycle Cost Analysis, Alec C. Danaher

Theses and Dissertations

Executive Order 13514 requires federal agencies to consider economic and social benefits and costs when evaluating projects and activities based on life-cycle return on investment. The generation of energy used by federal facilities imposes social externalities, most notably air pollution, upon society. This research utilized the social costs of carbon dioxide, oxides of nitrogen, and sulfur dioxide to develop a probabilistic life-cycle full-cost analysis tool for the analysis of energy efficiency projects. The tool was then used to investigate the effects of incorporating social externalities and uncertainty into life-cycle cost analyses of energy efficiency projects. Calculation of the social benefits …

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Ensemble Forecasting Of Coronal Mass Ejections Using The Wsa-Enlil With Coned Model, Daniel J. Emmons Ii Mar 2012

Ensemble Forecasting Of Coronal Mass Ejections Using The Wsa-Enlil With Coned Model, Daniel J. Emmons Ii

Theses and Dissertations

The combination of the Wang-Sheeley-Arge (WSA) coronal model, ENLIL heliospherical model version 2.7, and Coned Model version 1.3 (WSA-ENLIL with Coned Model) was employed to form ensemble forecasts for 15 halo coronal mass ejections (CME's). The input parameter distributions were formed from 100 sets of CME cone parameters derived from the Coned Model. The Coned Model employed image processing along with the bootstrap approach to automatically calculate cone parameter distributions from SOHO-LASCO imagery based on techniques described by Pulkkinen et al. [2010]. The input parameter distributions were used as input to WSA-ENLIL to calculate the temporal evolution of the …

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Design And Characterization Of A Three-Dimensional Positron Annihilation Spectroscopy System Using A Low-Energy Positron Beam, Stephen M. Jimenez Mar 2012

Design And Characterization Of A Three-Dimensional Positron Annihilation Spectroscopy System Using A Low-Energy Positron Beam, Stephen M. Jimenez

Theses and Dissertations

Previous forays by AFIT into positron research have resulted in the development of a new positron annihilation spectroscopy (PAS) technique and the procurement of a low-energy positron beam system. The primary purpose of this research was to design and build a state-of-the-art PAS laboratory at AFIT capable to address a myriad of DoD solid-state and surface physics questions. The main objectives were to acquire and assemble utilities to operate a positron beam, assemble and configure an ultra-high vacuum (UHV) system for samples, design and build an interface with a magnetic field to propagate positrons onto samples, and create a new …

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A Dempster-Shafer Method For Multi-Sensor Fusion, Bethany G. Foley Mar 2012

A Dempster-Shafer Method For Multi-Sensor Fusion, Bethany G. Foley

Theses and Dissertations

The Dempster-Shafer Theory, a generalization of the Bayesian theory, is based on the idea of belief and as such can handle ignorance. When all of the required information is available, many data fusion methods provide a solid approach. Yet, most do not have a good way of dealing with ignorance. In the absence of information, these methods must then make assumptions about the sensor data. However, the real data may not fit well within the assumed model. Consequently, the results are often unsatisfactory and inconsistent. The Dempster-Shafer Theory is not hindered by incomplete models or by the lack of prior …

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Context Aware Routing Management Architecture For Airborne Networks, Joan A. Betances Mar 2012

Context Aware Routing Management Architecture For Airborne Networks, Joan A. Betances

Theses and Dissertations

This thesis advocates the use of Kalman filters in conjunction with network topology information derived from the Air Tasking Order (ATO) during the planning phase for military missions. This approach is the basis for an algorithm that implements network controls that optimize network performance for Mobile Ad hoc Networks (MANET). The trajectories of relevant nodes (airborne platforms) participating in the MANET can be forecasted by parsing key information contained in the ATO. This information is used to develop optimum network routes that can significantly improve MANET performance. Improved MANET performance in the battlefield enables decision makers to access information from …

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An Analysis Of Error Reconciliation Protocols For Use In Quantum Key Distribution, James S. Johnson Mar 2012

An Analysis Of Error Reconciliation Protocols For Use In Quantum Key Distribution, James S. Johnson

Theses and Dissertations

Quantum Key Distribution (QKD) is a method for transmitting a cryptographic key between a sender and receiver in a theoretically unconditionally secure way. Unfortunately, the present state of technology prohibits the flawless quantum transmission required to make QKD a reality. For this reason, error reconciliation protocols have been developed which preserve security while allowing a sender and receiver to reconcile the errors in their respective keys. The most famous of these protocols is Brassard and Salvail's Cascade, which is effective, but suffers from a high communication complexity and therefore results in low throughput. Another popular option is Buttler's Winnow protocol, …

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Collisional Dynamics, Lasing And Stimulated Raman Scattering In Optically Pumped Cesium And Potassium Vapors, Kirk C. Brown Mar 2012

Collisional Dynamics, Lasing And Stimulated Raman Scattering In Optically Pumped Cesium And Potassium Vapors, Kirk C. Brown

Theses and Dissertations

This dissertation explores collisional dynamics, lasing and stimulated Raman scattering in cesium and potassium vapors. The spin orbit mixing and quenching cross sections of several buffer gas species are measured. The ne-structure mixing cross sections for He, CH4 and C2H6 are 14±3, 35±6 and 73±10 °A2, respectively. The 2P3/2 state is quenched more rapidly than the 2P1/2 state. A pulsed blue laser operating via direct excitation of the cesium 72P3/2 state is demonstrated. A theoretical model is extended and compared with experimental results. The maximum output …

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Fdtd Simulation Of Novel Polarimetric And Directional Refelectance And Transmittance Measurements From Optical Nano- And Micro-Structured Materials, Spencer R. Sellers Mar 2012

Fdtd Simulation Of Novel Polarimetric And Directional Refelectance And Transmittance Measurements From Optical Nano- And Micro-Structured Materials, Spencer R. Sellers

Theses and Dissertations

The basic physics of nano-/micro-structured materials must be categorized through measurements and simulation to fully understand their scatter dependence on polarization and angle on incidence before they can be considered for war fighter applications. The off-normal incidence and polarization dependant scatter for a guided-mode resonance filter (GMRF) and a surface plasmonic polariton (SPP) extraordinary transmission filter is measured. The measurements are compared to finite-difference time domain (FDTD) simulations. The GMRF is found to exhibit extraordinary angular scatter at the resonant coupled modes. An approximation is developed to predict the dependence of these modes on wavelength, incident angle and polarization. For …

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Comparative Analysis Of Two Biological Warfare Air Samplers Using Live Surrogate Agents, James C. Enderby Mar 2012

Comparative Analysis Of Two Biological Warfare Air Samplers Using Live Surrogate Agents, James C. Enderby

Theses and Dissertations

The United States Air Force has several high-volume biological air samplers, including the XMX/2L-MIL and the Biocapture 650. Limited information is available on either in terms of its collection of viruses and bacteria. However, previous research on the XMX/2L-MIL has determined that modifications to the secondary flow rate and the use of a virus preserving collection media may provide improved virus collection rates. In this thesis, these modifications were investigated to determine their impact on the collection of viral and bacterial aerosols. Additionally, relative collection rates were compared against those for the Biocapture 650. MS2 bacteriophage was the viral surrogate …

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Modeling The Impact Of Cracking In Low Permeability Layers In A Groundwater Contamination Source Zone On Dissolved Contamination Source Zone On Dissolved Contaminant Fate And Transport, Katherine W. Sievers Mar 2012

Modeling The Impact Of Cracking In Low Permeability Layers In A Groundwater Contamination Source Zone On Dissolved Contamination Source Zone On Dissolved Contaminant Fate And Transport, Katherine W. Sievers

Theses and Dissertations

The storage and transport of a dense non-aqueous phase liquid (DNAPL) was evaluated using a numerical model. Many DNAPLs are used as solvents by the DoD and industry. The improper disposal and handling of these chemicals has led to long term contamination of groundwater. When spilled, a DNAPL will pool atop low permeability layers and slowly dissolve creating a contaminant plume. The dissolved contaminant within a low permeability layer serves as long-term sources of contamination once the source is removed. In this study, cracks are hypothesized to exist in the low permeability layers, allowing for enhanced transport. A numerical model …

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Emissions From Simulated Open Burning Of Deployed Us Military Waste, Brian D. Woodall Mar 2012

Emissions From Simulated Open Burning Of Deployed Us Military Waste, Brian D. Woodall

Theses and Dissertations

U.S. military forces have relied primarily on open burning as an expedient method of volume reduction and treatment of solid waste during the conflicts in Afghanistan and Iraq. This study is the first effort to characterize a broad range of pollutants and their emission factors during the burning of military waste and the effects that recycling efforts, namely removing plastics, might have on emissions. Piles of simulated military waste were constructed, burned, and emissions sampled at the U.S. Environmental Protection Agency (EPA) Open Burn Testing Facility (OBTF), Research Triangle Park, NC. Three tests contained polyethylene terephthalate (PET #1 or PET) …

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Detector Design Considerations In High-Dimensional Artificial Immune Systems, Jason M. Bindewald Mar 2012

Detector Design Considerations In High-Dimensional Artificial Immune Systems, Jason M. Bindewald

Theses and Dissertations

This research lays the groundwork for a network intrusion detection system that can operate with only knowledge of normal network traffic, using a process known as anomaly detection. Real-valued negative selection (RNS) is a specific anomaly detection algorithm that can be used to perform two-class classification when only one class is available for training. Researchers have shown fundamental problems with the most common detector shape, hyperspheres, in high-dimensional space. The research contained herein shows that the second most common detector type, hypercubes, can also cause problems due to biasing certain features in high dimensions. To address these problems, a new …

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Understanding How Reverse Engineers Make Sense Of Programs From Assembly Language Representations, Adam R. Bryant Mar 2012

Understanding How Reverse Engineers Make Sense Of Programs From Assembly Language Representations, Adam R. Bryant

Theses and Dissertations

This dissertation develops a theory of the conceptual and procedural aspects involved with how reverse engineers make sense of executable programs. Software reverse engineering is a complex set of tasks which require a person to understand the structure and functionality of a program from its assembly language representation, typically without having access to the program's source code. This dissertation describes the reverse engineering process as a type of sensemaking, in which a person combines reasoning and information foraging behaviors to develop a mental model of the program. The structure of knowledge elements used in making sense of executable programs are …

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Obfuscating Against Side-Channel Power Analysis Using Hiding Techniques For Aes, Austin W. Fritzke Mar 2012

Obfuscating Against Side-Channel Power Analysis Using Hiding Techniques For Aes, Austin W. Fritzke

Theses and Dissertations

The transfer of information has always been an integral part of military and civilian operations, and remains so today. Because not all information we share is public, it is important to secure our data from unwanted parties. Message encryption serves to prevent all but the sender and recipient from viewing any encrypted information as long as the key stays hidden. The Advanced Encryption Standard (AES) is the current industry and military standard for symmetric-key encryption. While AES remains computationally infeasible to break the encrypted message stream, it is susceptible to side-channel attacks if an adversary has access to the appropriate …

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Scalable Wavelet-Based Active Network Stepping Stone Detection, Joseph I. Gilbert Mar 2012

Scalable Wavelet-Based Active Network Stepping Stone Detection, Joseph I. Gilbert

Theses and Dissertations

Network intrusions leverage vulnerable hosts as stepping stones to penetrate deeper into a network and mask malicious actions from detection. This research focuses on a novel active watermark technique using Discrete Wavelet Transformations to mark and detect interactive network sessions. This technique is scalable, nearly invisible and resilient to multi-flow attacks. The watermark is simulated using extracted timestamps from the CAIDA 2009 dataset and replicated in a live environment. The simulation results demonstrate that the technique accurately detects the presence of a watermark at a 5% False Positive and False Negative rate for both the extracted timestamps as well as …

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Binary Disassembly Block Coverage By Symbolic Execution Vs. Recursive Descent, Jonathan D. Miller Mar 2012

Binary Disassembly Block Coverage By Symbolic Execution Vs. Recursive Descent, Jonathan D. Miller

Theses and Dissertations

This research determines how appropriate symbolic execution is (given its current implementation) for binary analysis by measuring how much of an executable symbolic execution allows an analyst to reason about. Using the S2E Selective Symbolic Execution Engine with a built-in constraint solver (KLEE), this research measures the effectiveness of S2E on a sample of 27 Debian Linux binaries as compared to a traditional static disassembly tool, IDA Pro. Disassembly code coverage and path exploration is used as a metric for determining success. This research also explores the effectiveness of symbolic execution on packed or obfuscated samples of the same binaries …

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Covariance Analysis Of Vision Aided Navigation By Bootstrapping, Andrew L. Relyea Mar 2012

Covariance Analysis Of Vision Aided Navigation By Bootstrapping, Andrew L. Relyea

Theses and Dissertations

Inertial Navigation System (INS) aiding using bearing measurements taken over time of stationary ground features is investigated. A cross country flight, in two and three dimensional space, is considered, as well as a vertical drop in three dimensional space. The objective is to quantify the temporal development of the uncertainty in the navigation states of an aircraft INS which is aided by taking bearing measurements of ground objects which have been geolocated using ownship position. It is shown that during wings level flight at constant speed and a fixed altitude, an aircraft that tracks ground objects and over time sequentially …

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