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Articles 1 - 30 of 92
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Scattering Matrix Elements For The Nonadiabatic Collision B (2PJₐ) + H2 (1Σ+G, Ν, Ј) ↔ B (2PJ’ₐ) + H2 (1Σ+G, Ν’, J’)., Luke A. Barger
Scattering Matrix Elements For The Nonadiabatic Collision B (2PJₐ) + H2 (1Σ+G, Ν, Ј) ↔ B (2PJ’ₐ) + H2 (1Σ+G, Ν’, J’)., Luke A. Barger
Theses and Dissertations
Scattering matrix elements are calculated for the nonadiabatic inelastic collision B (2Pjₐ) + H2 (1Σ+g, ν, ј) ↔ B (2Pj’ₐ) + H2 (1Σ+g, ν’, j’). This calculation utilizes the effective potential energy surfaces for this collision generated by Garvin along with a correction to the asymptotic H2 potential. Wavepackets are propagated on these surfaces using a split-operator propagator. This propagation yields correlation functions between reactant and product Møller states which are used to calculate the scattering …
Tunable Optical Delay In Doppler-Broadened Cesium Vapor, Monte D. Anderson
Tunable Optical Delay In Doppler-Broadened Cesium Vapor, Monte D. Anderson
Theses and Dissertations
Variable-delay tunable optical delay line or optical buffers are critical for the development of all-optical networks components as well as interferometry and analytic instruments. Recent research on slow light may hold the key for the development of the first practical tunable optical delay device. In this research the linear dispersion delay effects in an alkali vapor. The hyperfine relaxation observations present insight into the complex bleach wave dynamics during a high-intensity pulsed pump in DPAL systems.
Measurement And Modeling Of Infrared Nonlinear Absorption Coefficients And Laser-Induced Damage Thresholds In Ge And Gasb, Torrey J. Wagner, Matthew J. Bohn, Ronald A. Coutu Jr., L. P. Gonzales, J. M. Murray, K. L. Schepler, S. Guha
Measurement And Modeling Of Infrared Nonlinear Absorption Coefficients And Laser-Induced Damage Thresholds In Ge And Gasb, Torrey J. Wagner, Matthew J. Bohn, Ronald A. Coutu Jr., L. P. Gonzales, J. M. Murray, K. L. Schepler, S. Guha
Faculty Publications
Using a simultaneous fitting technique to extract nonlinear absorption coefficients from data at two pulse widths, we measure two-photon and free-carrier absorption coefficients for Ge and GaSb at 2.05 and 2.5 µm for the first time, to our knowledge. Results agreed well with published theory. Single-shot damage thresholds were also measured at 2.5 µm and agreed well with modeled thresholds using experimentally determined parameters including nonlinear absorption coefficients and temperature dependent linear absorption. The damage threshold for a single-layer Al2O3 anti-reflective coating on Ge was 55% or 35% lower than the uncoated threshold for picosecond or nanosecond …
Electronic Image Stabilization Using Optical Flow With Inertial Fusion, Michael J. Smith, Alexander J. Boxerbaum, Gilbert L. Peterson, Roger D. Quinn
Electronic Image Stabilization Using Optical Flow With Inertial Fusion, Michael J. Smith, Alexander J. Boxerbaum, Gilbert L. Peterson, Roger D. Quinn
Faculty Publications
When a camera is affixed on a dynamic mobile robot, image stabilization is the first step towards more complex analysis on the video feed. This paper presents a novel electronic image stabilization (EIS) algorithm for highly dynamic mobile robotic platforms. The algorithm combines optical flow motion parameter estimation with angular rate data provided by a strapdown inertial measurement unit (IMU). A discrete Kalman filter in feedforward configuration is used for optimal fusion of the two data sources. Performance evaluations are conducted using a simulated video truth model (capturing the effects of image translation, rotation, blurring, and moving objects), and live …
Determining The Index Of Refraction Of An Unknown Object Using Passive Polarimetric Imagery Degraded By Atmospheric Turbulence, Milo W. Hyde Iv
Determining The Index Of Refraction Of An Unknown Object Using Passive Polarimetric Imagery Degraded By Atmospheric Turbulence, Milo W. Hyde Iv
Theses and Dissertations
In this research, an algorithm is developed to estimate the index of refraction of an unknown object using passive polarimetric images degraded by atmospheric turbulence. The algorithm uses a variant of the maximum-likelihood blind-deconvolution algorithm developed by LeMaster and Cain to recover the true object (i.e., the first Stokes parameter), the degree of linear polarization, and the polarimetric-image point spread functions. Nonlinear least squares is then used to find the value of the complex index of refraction which best fits the theoretical degree of linear polarization, derived using a polarimetric bidirectional reflectance distribution function, to the turbulence-corrected degree of linear …
Collisional Dynamics Of The Cesium D1 And D2 Transitions, Greg A. Pitz
Collisional Dynamics Of The Cesium D1 And D2 Transitions, Greg A. Pitz
Theses and Dissertations
The collisional dynamics of the 62P levels in cesium have been studied utilizing steady state laser absorption and laser induced florescence techniques. In addition the production of a blue beam produced by two photon absorption has been observed in potassium. The collisional broadening rate for cesium, λL, for He, Ne, Ar, Kr, Xe, N2, H2, HD, D2, CH4, C2H6, CF4, and 3He are 24.13, 10.85, 18.31, 17.82, 19.74, 16.64, 20.81, 20.06, 18.04, 29.00, 26.70, 18.84, and 26.00 MHz/torr, respectively for the …
Laser Demonstration And Performance Characterization Of An Optically Pumped Alkali Laser System, Clifford V. Sulham
Laser Demonstration And Performance Characterization Of An Optically Pumped Alkali Laser System, Clifford V. Sulham
Theses and Dissertations
Diode Pumped Alkali Lasers (DPALs) offer a promising approach for high power lasers in military applications that will not suffer from the long logistical trails of chemical lasers or the thermal management issues of diode pumped solid state lasers. This research focuses on characterizing a DPAL-type system to gain a better understanding of using this type of laser as a directed energy weapon. A rubidium laser operating at 795 nm is optically pumped by a pulsed titanium sapphire laser to investigate the dynamics of DPALs at pump intensities between 1.3 and 45 kW/cm2. Linear scaling as high as …
Reputation-Based Internet Protocol Security: A Multilayer Security Framework For Mobil Ad Hoc Networks, Timothy H. Lacey
Reputation-Based Internet Protocol Security: A Multilayer Security Framework For Mobil Ad Hoc Networks, Timothy H. Lacey
Theses and Dissertations
This research effort examines the theory, application, and results for a Reputation-based Internet Protocol Security (RIPSec) framework that provides security for an ad-hoc network operating in a hostile environment. In RIPSec, protection from external threats is provided in the form of encrypted communication links and encryption-wrapped nodes while internal threats are mitigated by behavior grading that assigns reputations to nodes based on their demonstrated participation in the routing process. Network availability is provided by behavior grading and round-robin multipath routing. If a node behaves faithfully, it earns a positive reputation over time. If a node misbehaves (for any number of …
Cyber Situational Awareness Using Live Hypervisor-Based Virtual Machine Introspection, Dustyn A. Dodge
Cyber Situational Awareness Using Live Hypervisor-Based Virtual Machine Introspection, Dustyn A. Dodge
Theses and Dissertations
In this research, a compiled memory analysis tool for virtualization (CMAT-V) is developed as a virtual machine introspection (VMI) utility to conduct live analysis during cyber attacks. CMAT-V leverages static memory dump analysis techniques to provide live dynamic system state data. Unlike some VMI applications, CMAT-V bridges the semantic gap using derivation techniques. CMAT-V detects Windows-based operating systems and uses the Microsoft Symbol Server to provide this context to the user. This research demonstrates the usefulness of CMAT-V as a situational awareness tool during cyber attacks, tests the detection of CMAT-V from the guest system level and measures its impact …
Code White: A Signed Code Protection Mechanism For Smartphones, Joseph M. Hinson Iv
Code White: A Signed Code Protection Mechanism For Smartphones, Joseph M. Hinson Iv
Theses and Dissertations
This research develops Code White, a hardware-implemented trusted execution mechanism for the Symbian mobile operating system. Code White combines a signed whitelist approach with the execution prevention technology offered by the ARM architecture. Testing shows that it prevents all untrusted user applications from executing while allowing all trusted applications to load and run. Performance testing in contrast with an unmodified Symbian system shows that the difference in load time increases linearly as the application file size increases. The predicted load time for an application with a one megabyte code section remains well below one second, ensuring uninterrupted experience for the …
Accelerating Malware Detection Via A Graphics Processing Unit, Nicholas S. Kovach
Accelerating Malware Detection Via A Graphics Processing Unit, Nicholas S. Kovach
Theses and Dissertations
Real-time malware analysis requires processing large amounts of data storage to look for suspicious files. This is a time consuming process that (requires a large amount of processing power) often affecting other applications running on a personal computer. This research investigates the viability of using Graphic Processing Units (GPUs), present in many personal computers, to distribute the workload normally processed by the standard Central Processing Unit (CPU). Three experiments are conducted using an industry standard GPU, the NVIDIA GeForce 9500 GT card. The goal of the first experiment is to find the optimal number of threads per block for calculating …
Hijacking User Uploads To Online Persistent Data Repositories For Covert Data Exfiltration, Curtis P. Barnard
Hijacking User Uploads To Online Persistent Data Repositories For Covert Data Exfiltration, Curtis P. Barnard
Theses and Dissertations
As malware has evolved over the years, it has gone from harmless programs that copy themselves into other executables to modern day botnets that perform bank fraud and identity theft. Modern malware often has a need to communicate back to the author, or other machines that are also infected. Several techniques for transmitting this data covertly have been developed over the years which vary significantly in their level of sophistication. This research creates a new covert channel technique for stealing information from a network by piggybacking on user-generated network traffic. Specifically, steganography drop boxes and passive covert channels are merged …
A Comparative Analysis Of Ascii And Xml Logging Systems, Eric C. Hanington
A Comparative Analysis Of Ascii And Xml Logging Systems, Eric C. Hanington
Theses and Dissertations
This research compares XML and ASCII based event logging systems in terms of their storage and processing efficiency. XML has been an emerging technology, even for security. Therefore, it is researched as a logging system with the mitigation of its verbosity. Each system consists of source content, the network transmission, database storage, and querying which are all studied as individual parts. The ASCII logging system consists of the text file as source, FTP as transport, and a relational database system for storage and querying. The XML system has the XML files and XML files in binary form using Efficient XML …
Neural Extensions To Robust Parameter Design, Bernard Jacob Loeffelholz
Neural Extensions To Robust Parameter Design, Bernard Jacob Loeffelholz
Theses and Dissertations
Robust parameter design (RPD) is implemented in systems in which a user wants to minimize the variance of a system response caused by uncontrollable factors while obtaining a consistent and reliable system response over time. We propose the use of artificial neural networks to compensate for highly non-linear problems that quadratic regression fails to accurately model. RPD is conducted under the assumption that the relationship between system response and controllable and uncontrollable variables does not change over time. We propose a methodology to find a new set of settings that will be robust to moderate system degradation while remaining robust …
Statistical Image Recovery From Laser Speckle Patterns With Polarization Diversity, Donald B. Dixon
Statistical Image Recovery From Laser Speckle Patterns With Polarization Diversity, Donald B. Dixon
Theses and Dissertations
This research extends the theory and understanding of the laser speckle imaging technique. This non-traditional imaging technique may be employed to improve space situational awareness and image deep space objects from a ground-based sensor system. The use of this technique is motivated by the ability to overcome aperture size limitations and the distortion effects from Earth’s atmosphere. Laser speckle imaging is a lensless, coherent method for forming two-dimensional images from their autocorrelation functions. Phase retrieval from autocorrelation data is an ill-posed problem where multiple solutions exist. This research introduces polarization diversity as a method for obtaining additional information so the …
Consistency Properties For Growth Model Parameters Under An Infill Asymptotics Domain, David T. Mills
Consistency Properties For Growth Model Parameters Under An Infill Asymptotics Domain, David T. Mills
Theses and Dissertations
Growth curves are used to model various processes, and are often seen in biological and agricultural studies. Underlying assumptions of many studies are that the process may be sampled forever, and that samples are statistically independent. We instead consider the case where sampling occurs in a finite domain, so that increased sampling forces samples closer together, and also assume a distance-based covariance function. We first prove that, under certain conditions, the mean parameter of a fixed-mean model cannot be estimated within a finite domain. We then numerically consider more complex growth curves, examining sample sizes, sample spacing, and quality of …
All Solid-State Mid-Ir Laser Development, Nonlinear Absorption Investigation And Laser-Induced Damage Study, Torrey J. Wagner
All Solid-State Mid-Ir Laser Development, Nonlinear Absorption Investigation And Laser-Induced Damage Study, Torrey J. Wagner
Theses and Dissertations
In this research, nonlinear optical absorption coefficients and laser-induced damage thresholds are measured in Ge and GaSb, which are materials that are used in IR detectors. Using a simultaneous fitting technique to extract nonlinear absorption coefficients from data at two pulse widths, two-photon and free-carrier absorption coefficients are measured in Ge and GaSb at 2.05 and 2.5 μm for the first time. At these wavelengths, nonlinear absorption is the primary damage mechanism, and damage thresholds at picosecond and nanosecond pulse widths were measured and agreed well with modeled thresholds using experimentally measured parameters. The damage threshold for a single-layer Al …
Malware Type Recognition And Cyber Situational Awareness, Thomas Dube, Richard A. Raines, Gilbert L. Peterson, Kenneth W. Bauer, Michael R. Grimaila, Steven K. Rogers
Malware Type Recognition And Cyber Situational Awareness, Thomas Dube, Richard A. Raines, Gilbert L. Peterson, Kenneth W. Bauer, Michael R. Grimaila, Steven K. Rogers
Faculty Publications
Current technologies for computer network and host defense do not provide suitable information to support strategic and tactical decision making processes. Although pattern-based malware detection is an active research area, the additional context of the type of malware can improve cyber situational awareness. This additional context is an indicator of threat capability thus allowing organizations to assess information losses and focus response actions appropriately. Malware Type Recognition (MaTR) is a research initiative extending detection technologies to provide the additional context of malware types using only static heuristics. Test results with MaTR demonstrate over a 99% accurate detection rate and 59% …
Analytical Solutions For Efficient Interpretation Of Single-Well Push-Pull Tracer Tests, Junqi Huang, John A. Christ, Mark N. Goltz
Analytical Solutions For Efficient Interpretation Of Single-Well Push-Pull Tracer Tests, Junqi Huang, John A. Christ, Mark N. Goltz
Faculty Publications
Single-well push-pull tracer tests have been used to characterize the extent, fate, and transport of subsurface contamination. Analytical solutions provide one alternative for interpreting test results. In this work, an exact analytical solution to two-dimensional equations describing the governing processes acting on a dissolved compound during a modified push-pull test (advection, longitudinal and transverse dispersion, first-order decay, and rate-limited sorption/partitioning in steady, divergent, and convergent flow fields) is developed. The coupling of this solution with inverse modeling to estimate aquifer parameters provides an efficient methodology for subsurface characterization. Synthetic data for single-well push-pull tests are employed to demonstrate the utility …
Simulating Windows-Based Cyber Attacks Using Live Virtual Machine Introspection, Dustyn A. Dodge, Barry E. Mullins, Gilbert L. Peterson, James S. Okolica
Simulating Windows-Based Cyber Attacks Using Live Virtual Machine Introspection, Dustyn A. Dodge, Barry E. Mullins, Gilbert L. Peterson, James S. Okolica
Faculty Publications
Static memory analysis has been proven a valuable technique for digital forensics. However, the memory capture technique halts the system causing the loss of important dynamic system data. As a result, live analysis techniques have emerged to complement static analysis. In this paper, a compiled memory analysis tool for virtualization (CMAT-V) is presented as a virtual machine introspection (VMI) utility to conduct live analysis during simulated cyber attacks. CMAT-V leverages static memory dump analysis techniques to provide live system state awareness. CMAT-V parses an arbitrary memory dump from a simulated guest operating system (OS) to extract user information, network usage, …
Deterministic, Efficient Variation Of Circuit Components To Improve Resistance To Reverse Engineering, Daniel F. Koranek
Deterministic, Efficient Variation Of Circuit Components To Improve Resistance To Reverse Engineering, Daniel F. Koranek
Theses and Dissertations
This research proposes two alternative methods for generating semantically equivalent circuit variants which leave the circuit's internal structure pseudo-randomly determined. Component fusion deterministically selects subcircuits using a component identification algorithm and replaces them using a deterministic algorithm that generates canonical logic forms. Component encryption seeks to alter the semantics of individual circuit components using an encoding function, but preserves the overall circuit semantics by decoding signal values later in the circuit. Experiments were conducted to examine the performance of component fusion and component encryption against representative trials of subcircuit selection-and-replacement and Boundary Blurring, two previously defined methods for circuit obfuscation. …
Realistic Vertical Atmospheric Profiles And Effects From Limited Surface Observations, Dane P. Ranney
Realistic Vertical Atmospheric Profiles And Effects From Limited Surface Observations, Dane P. Ranney
Theses and Dissertations
The ability to accurately describe the atmospheric conditions around us is not only important to the Air Force, but to anyone involved in signal propagation. The programs currently utilized to describe the atmosphere take into account a variety of measures. The LEEDR (Laser Environmental Effects Definition and Reference) program in particular, allows the user to select a location, aerosol and molecular effects model, numerous cloud and precipitation events, as well as other features. Even with the control that the user has, the output that the program provides can vary from actual conditions on a day to day basis. This is …
The Combined Effects Of Radio Frequency And Gamma Irradiation On P-Channel Mosfets, Joshua D. Daniel
The Combined Effects Of Radio Frequency And Gamma Irradiation On P-Channel Mosfets, Joshua D. Daniel
Theses and Dissertations
The purpose of this research was to investigate the combined effects of continuous gigahertz radio frequency signals and gamma irradiation on the threshold voltage of metal oxide semiconductor field effect transistors. The combined effects of gigahertz radio frequency waves and gamma irradiation on electronics presents a new challenge in electronic warfare and little is known of the combined effect on threshold voltage damage and recovery. The Fairchild NDS352AP, a commonly used commercial device, was irradiated by a cobalt-60 source under a +5 V bias with and without a radio frequency signal applied to the gate. The threshold voltage was measured …
Developing A Hybrid Virtualization Platform Design For Cyber Warfare And Simulation, Kyle E. Stewart
Developing A Hybrid Virtualization Platform Design For Cyber Warfare And Simulation, Kyle E. Stewart
Theses and Dissertations
Virtualization is a technique used to model and simulate the cyber domain, as well as train and educate. Different types of virtualization techniques exist that each support a unique set of benefits and requirements. This research proposes a novel design that incorporates host and network virtualization concepts for a cyber warfare training platform. At the host level, hybrid virtualization combines full and operating system virtualization techniques in order to leverage the benefits and minimize the drawbacks of each individual technique. Network virtualization allows virtual machines to connect in flexible topologies, but it also incurs additional processing overhead. Quantitative analysis falls …
An Application Of Automated Theorem Provers To Computer System Security: The Schematic Protection Model, Mitchell D.I. Hirschfeld
An Application Of Automated Theorem Provers To Computer System Security: The Schematic Protection Model, Mitchell D.I. Hirschfeld
Theses and Dissertations
The Schematic Protection Model is specified in SAL and theorems about Take-Grant and New Technology File System schemes are proven. Arbitrary systems can be specified in SPM and analyzed. This is the first known automated analysis of SPM specifications in a theorem prover. The SPM specification was created in such a way that new specifications share the underlying framework and are configurable within the specifications file alone. This allows new specifications to be created with ease as demonstrated by the four unique models included within this document. This also allows future users to more easily specify models without recreating the …
Electronic Structure Of Lithium Tetraborate, David J. Wooten
Electronic Structure Of Lithium Tetraborate, David J. Wooten
Theses and Dissertations
Due to interest as neutron detection material, an investigation of Li2B4O7(110) and Li2B4O7(100) was undertaken, utilizing photoemission and inverse photoemission spectroscopic techniques. The measured band gap depended on crystallographic direction with the band gaps ranging from 8.9±0.5 eV to 10.1±0.5 eV. The measurement yielded a density of states that qualitatively agreed with the theoretical results from model bulk band structure calculations for Li2B4O7; albeit with a larger band gap than predicted, but consistent with the known deficiencies of LDA and DFT calculations. …
Developing Cyberspace Data Understanding Using Crisp-Dm For Host-Based Ids Feature Mining, Joseph R. Erskine, Gilbert L. Peterson, Barry E. Mullins, Michael R. Grimaila
Developing Cyberspace Data Understanding Using Crisp-Dm For Host-Based Ids Feature Mining, Joseph R. Erskine, Gilbert L. Peterson, Barry E. Mullins, Michael R. Grimaila
Faculty Publications
Current intrusion detection systems (IDS) generate a large number of specific alerts, but typically do not provide actionable information. Compounding this problem is the fact that many alerts are false positive alerts. This paper applies the Cross Industry Standard Process for Data Mining (CRISP-DM) to develop an understanding of a host environment under attack. Data is generated by launching scans and exploits at a machine outfitted with a set of host-based forensic data collectors. Through knowledge discovery, features are selected to project human understanding of the attack process into the IDS model. By discovering relationships between the data collected and …
Performance Characteristics Of A Kernel-Space Packet Capture Module, Samuel W. Birch
Performance Characteristics Of A Kernel-Space Packet Capture Module, Samuel W. Birch
Theses and Dissertations
Defending networks, network-connected assets, and the information they both carry and store is an operational challenge and a significant drain on resources. A plethora of historical and ongoing research efforts are focused on increasing the effectiveness of the defenses or reducing the costs of existing defenses. One valuable facet in defense is the ability to perform post mortem analysis of incidents that have occurred, and this tactic requires accurate storage and rapid retrieval of vast quantities of historical network data. This research improves the efficiency of capturing network packets to disk using commodity, general-purpose hardware and operating systems. It examines …
Utilizing The Digital Fingerprint Method For Secure Key Generation, Jennifer C. Anilao
Utilizing The Digital Fingerprint Method For Secure Key Generation, Jennifer C. Anilao
Theses and Dissertations
This research examines a new way to generate an uncloneable secure key by taking advantage of the delay characteristics of individual transistors. The user profiles the circuit to deduce the glitch count of each output line for each number of selectable buffers added to the circuit. The user can then use this information to generate a specific glitch count on each output line, which is passed to an encryption algorithm as its key. The results detail tests of two configurations for adding a selectable amount of buffers into each glitch circuit in order to induce additional delay. One configuration adds …
Improved Modeling Of Midlatitude D-Region Ionospheric Absorption Of High Frequency Radio Signals During Solar X-Ray Flares, Evelyn A. Schumer
Improved Modeling Of Midlatitude D-Region Ionospheric Absorption Of High Frequency Radio Signals During Solar X-Ray Flares, Evelyn A. Schumer
Theses and Dissertations
The purpose of this research was to improve modeling of midlatitude D-region ionospheric absorption of high frequency radio signals during solar X-ray flares through analysis of HF propagation data obtained during the HF Investigation of D-region Ionospheric Variation Experiment (HIDIVE) and obtained at the Canadian Space Agency NORSTAR riometer in Pinawa, Manitoba, Canada and X-ray flux data, as reported by GOES satellites. The findings of the data analysis were then used to validate and suggest improvements for two existing HF absorption models, the operational Space Weather Prediction Center (SWPC) D-region Absorption model and the physical AbbyNormal model. Analysis of the …