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Articles 1531 - 1560 of 3056
Full-Text Articles in Physical Sciences and Mathematics
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. …
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. …
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 …
A Locally Adaptable Iterative Rx Detector, Yuri P. Taitano, Brian G. Geier, Kenneth W. Bauer
A Locally Adaptable Iterative Rx Detector, Yuri P. Taitano, Brian G. Geier, Kenneth W. Bauer
Faculty Publications
We present an unsupervised anomaly detection method for hyperspectral imagery (HSI) based on data characteristics inherit in HSI. A locally adaptive technique of iteratively refining the well-known RX detector (LAIRX) is developed. The technique is motivated by the need for better first- and second-order statistic estimation via avoidance of anomaly presence. Overall, experiments show favorable Receiver Operating Characteristic (ROC) curves when compared to a global anomaly detector based upon the Support Vector Data Description (SVDD) algorithm, the conventional RX detector, and decomposed versions of the LAIRX detector. Furthermore, the utilization of parallel and distributed processing allows fast processing time making …
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 …
Developing A Qualia-Based Multi-Agent Architecture For Use In Malware Detection, Bobby D. Birrer
Developing A Qualia-Based Multi-Agent Architecture For Use In Malware Detection, Bobby D. Birrer
Theses and Dissertations
Detecting network intruders and malicious software is a significant problem for network administrators and security experts. New threats are emerging at an increasing rate, and current signature and statistics-based techniques are not keeping pace. Intelligent systems that can adapt to new threats are needed to mitigate these new strains of malware as they are released. This research detects malware based on its qualia, or essence rather than its low-level implementation details. By looking for the underlying concepts that make a piece of software malicious, this research avoids the pitfalls of static solutions that focus on predefined bit sequence signatures or …
Development Of A Methodology For Customizing Insider Threat Auditing On A Linux Operating System, William T. Bai
Development Of A Methodology For Customizing Insider Threat Auditing On A Linux Operating System, William T. Bai
Theses and Dissertations
Insider threats can pose a great risk to organizations and by their very nature are difficult to protect against. Auditing and system logging are capabilities present in most operating systems and can be used for detecting insider activity. However, current auditing methods are typically applied in a haphazard way, if at all, and are not conducive to contributing to an effective insider threat security policy. This research develops a methodology for designing a customized auditing and logging template for a Linux operating system. An intent-based insider threat risk assessment methodology is presented to create use case scenarios tailored to address …
A Distributed Network Logging Topology, Nicholas E. Fritts
A Distributed Network Logging Topology, Nicholas E. Fritts
Theses and Dissertations
Network logging is used to monitor computer systems for potential problems and threats by network administrators. Research has found that the more logging enabled, the more potential threats can be detected in the logs (Levoy, 2006). However, generally it is considered too costly to dedicate the manpower required to analyze the amount of logging data that it is possible to generate. Current research is working on different correlation and parsing techniques to help filter the data, but these methods function by having all of the data dumped in to a central repository. Central repositories are limited in the amount of …
Visually Managing Ipsec, Peter J. Dell'accio
Visually Managing Ipsec, Peter J. Dell'accio
Theses and Dissertations
The United States Air Force relies heavily on computer networks to transmit vast amounts of information throughout its organizations and with agencies throughout the Department of Defense. The data take many forms, utilize different protocols, and originate from various platforms and applications. It is not practical to apply security measures specific to individual applications, platforms, and protocols. Internet Protocol Security (IPsec) is a set of protocols designed to secure data traveling over IP networks, including the Internet. By applying security at the network layer of communications, data packets can be secured regardless of what application generated the data or which …
Handshaking Protocols And Jamming Mechanisms For Blind Rendezvous In A Dynamic Spectrum Access Environment, Aaron A. Gross
Handshaking Protocols And Jamming Mechanisms For Blind Rendezvous In A Dynamic Spectrum Access Environment, Aaron A. Gross
Theses and Dissertations
Blind frequency rendezvous is an important process for bootstrapping communications between radios without the use of pre-existing infrastructure or common control channel in a Dynamic Spectrum Access (DSA) environment. In this process, radios attempt to arrive in the same frequency channel and recognize each other’s presence in changing, under-utilized spectrum. This paper refines existing blind rendezvous techniques by introducing a handshaking algorithm for setting up communications once two radios have arrived in the same frequency channel. It then investigates the effect of different jamming techniques on blind rendezvous algorithms that utilize this handshake. The handshake performance is measured by determining …
Codifying Information Assurance Controls For Department Of Defense (Dod) Supervisory Control And Data Acquisition (Scada) Systems (U), Eddie A. Mendezllovet
Codifying Information Assurance Controls For Department Of Defense (Dod) Supervisory Control And Data Acquisition (Scada) Systems (U), Eddie A. Mendezllovet
Theses and Dissertations
Protecting DoD critical infrastructure resources and Supervisory Control and Data Acquisition (SCADA) systems from cyber attacks is becoming an increasingly challenging task. DoD Information Assurance controls provide a sound framework to achieve an appropriate level of confidentiality, integrity, and availability. However, these controls have not been updated since 2003 and currently do not adequately address the security of DoD SCADA systems. This research sampled U.S. Air Force Civil Engineering subject matter experts representing eight Major Commands that manage and operate SCADA systems. They ranked 30 IA controls in three categories, and evaluated eight SCADA specific IA controls for inclusion into …
Developing Cyberspace Data Understanding: Using Crisp-Dm For Host-Based Ids Feature Mining, Joseph R. Erskine
Developing Cyberspace Data Understanding: Using Crisp-Dm For Host-Based Ids Feature Mining, Joseph R. Erskine
Theses and Dissertations
Current intrusion detection systems generate a large number of specific alerts, but do not provide actionable information. Many times, these alerts must be analyzed by a network defender, a time consuming and tedious task which can occur hours or days after an attack occurs. Improved understanding of the cyberspace domain can lead to great advancements in Cyberspace situational awareness research and development. This thesis applies the Cross Industry Standard Process for Data Mining (CRISP-DM) to develop an understanding about a host system under attack. Data is generated by launching scans and exploits at a machine outfitted with a set of …
Augmenting Latent Dirichlet Allocation And Rank Threshold Detection With Ontologies, Laura A. Isaly
Augmenting Latent Dirichlet Allocation And Rank Threshold Detection With Ontologies, Laura A. Isaly
Theses and Dissertations
In an ever-increasing data rich environment, actionable information must be extracted, filtered, and correlated from massive amounts of disparate often free text sources. The usefulness of the retrieved information depends on how we accomplish these steps and present the most relevant information to the analyst. One method for extracting information from free text is Latent Dirichlet Allocation (LDA), a document categorization technique to classify documents into cohesive topics. Although LDA accounts for some implicit relationships such as synonymy (same meaning) it often ignores other semantic relationships such as polysemy (different meanings), hyponym (subordinate), meronym (part of), and troponomys (manner). To …
Evolutionary Artificial Neural Network Weight Tuning To Optimize Decision Making For An Abstract Game, Corey M. Miller
Evolutionary Artificial Neural Network Weight Tuning To Optimize Decision Making For An Abstract Game, Corey M. Miller
Theses and Dissertations
Abstract strategy games present a deterministic perfect information environment with which to test the strategic capabilities of artificial intelligence systems. With no unknowns or random elements, only the competitors’ performances impact the results. This thesis takes one such game, Lines of Action, and attempts to develop a competitive heuristic. Due to the complexity of Lines of Action, artificial neural networks are utilized to model the relative values of board states. An application, pLoGANN (Parallel Lines of Action with Genetic Algorithm and Neural Networks), is developed to train the weights of this neural network by implementing a genetic algorithm over a …
Developing An Effective And Efficient Real Time Strategy Agent For Use As A Computer Generated Force, Kurt Weissgerber
Developing An Effective And Efficient Real Time Strategy Agent For Use As A Computer Generated Force, Kurt Weissgerber
Theses and Dissertations
Computer Generated Forces (CGF) are used to represent units or individuals in military training and constructive simulation. The use of CGF significantly reduces the time and money required for effective training. For CGF to be effective, they must behave as a human would in the same environment. Real Time Strategy (RTS) games place players in control of a large force whose goal is to defeat the opponent. The military setting of RTS games makes them an excellent platform for the development and testing of CGF. While there has been significant research in RTS agent development, most of the developed agents …
Effects Of Channel Mismatches On Beamforming And Signal Detection, Christopher I. Allen
Effects Of Channel Mismatches On Beamforming And Signal Detection, Christopher I. Allen
Theses and Dissertations
Tuner gain measurements of a multichannel receiver are reported. A linear regression model is used to characterize the gain, as a function of channel number, tuner set-on frequency, and intermediate frequency. Residual errors of this model are characterized by a t distribution. Very strong autocorrelation of tuner gain at various frequencies is noted. Tuner performance from one channel to the next is diverse; several defects at specific frequencies are noted. The Wilcoxon signed rank test is used to test normality of tuner gain among devices; normality is rejected. Antenna directivity and phase pattern measurements are also reported. An antenna element …
Frequency Diverse Array Radar: Signal Characterization And Measurement Accuracy, Steven H. Brady
Frequency Diverse Array Radar: Signal Characterization And Measurement Accuracy, Steven H. Brady
Theses and Dissertations
Radar systems provide an important remote sensing capability, and are crucial to the layered sensing vision; a concept of operation that aims to apply the right number of the right types of sensors, in the right places, at the right times for superior battle space situational awareness. The layered sensing vision poses a range of technical challenges, including radar, that are yet to be addressed. To address the radar-specific design challenges, the research community responded with waveform diversity; a relatively new field of study which aims reduce the cost of remote sensing while improving performance. Early work suggests that the …
Numerical Investigation Of Pre-Detonator Geometries For Pde Applications, Robert T. Fievisohn
Numerical Investigation Of Pre-Detonator Geometries For Pde Applications, Robert T. Fievisohn
Theses and Dissertations
A parametric study was performed to determine optimal geometries to allow the successful transition of a detonation from a pre-detonator into the thrust tube of a pulse detonation engine. The study was performed using a two-dimensional Euler solver with progress variables to model the chemistry. The geometrical configurations for the simulations look at the effect of shock reflections, flow obstructions, and detonation diffraction to determine successful geometries. It was observed that there are success and failure rates associated with pre-detonators. These success rates appear to be determined by the transverse wave structure of a stably propagating detonation wave and must …
Validation Of A Novel Approach To Solving Multibody Systems Using Hamilton's Weak Principle, Ashton D. Hainge
Validation Of A Novel Approach To Solving Multibody Systems Using Hamilton's Weak Principle, Ashton D. Hainge
Theses and Dissertations
A novel approach for formulating and solving for the dynamic response of multibody systems has been developed using Hamilton’s Law of Varying Action as its unifying principle. In order to assure that the associated computer program is sufficiently robust when applied across a wide range of dynamic systems, the program must be verified and validated. The purpose of the research was to perform the verification and validation of the program. Results from the program were compared with closed-form and numerical solutions of simple systems, such as a simple pendulum and a rotating pendulum. The accuracy of the program for complex …
Verification Of Kam Theory On Earth Orbiting Satellites, Christian L. Bisher
Verification Of Kam Theory On Earth Orbiting Satellites, Christian L. Bisher
Theses and Dissertations
This paper uses KAM torus theory and Simplified General Perturbations 4 (SGP4) orbit prediction techniques compiled by Dr. William Wiesel and compares it to Analytical Graphics ® Incorporated (AGI) Satellite Toolkit ® (STK) orbit data. The goal of this paper is to verify KAM torus theory can be used to describe and propagate an Earth satellite orbit with similar accuracy to existing general perturbation techniques. Using SGP4 code including only truncated geopotential effects, KAM torus generating code, and other utilities were used to describe a particular satellite orbit as a torus and then propagate the satellite using traditional and KAM …
Hard Collisions In Rubidium Using Sub-Doppler Spectroscopy, Douglas E. Thornton
Hard Collisions In Rubidium Using Sub-Doppler Spectroscopy, Douglas E. Thornton
Theses and Dissertations
To better understand the laser kinetics of an alkali gain medium, hard collisions, or velocity-changing collisions, has been studied and a velocity-changing collisional rate has been calculated. Previous works have studied these collisions, but no rate has been calculated. Using the precise tool of sub-Doppler spectroscopy, atomic hard collisions can be observed. The collected spectra are fitted with two different line shapes to demonstrate the accuracy of this method. From the fits, the number of hard collisions can be extracted. The time scale of the hard collisions in rubidium is interpolated by varying the chopping frequency of the pump beam, …
Fuel Savings Opportunities From Air Refueling, Murat Toydas
Fuel Savings Opportunities From Air Refueling, Murat Toydas
Theses and Dissertations
Fuel is a critical strategic asset for military aviation operations, yet is increasingly expensive. Air refueling offers both the opportunity to extend aircraft range and the potential to save fuel by enabling a transport aircraft to depart with less fuel in exchange for additional cargo. We evaluate the practicality of air refueling in terms of fuel savings versus distance and cargo quantity, by introducing two non-linear optimization models that examine the tradeoff between departure fuel weight and loaded cargo for given origin, destination, and tanker base positions and freight quantities to be moved. We use various numerical example scenarios to …
A Multi-Objective Approach To A Bipartite Assignment Matching Problem Using Weighted Values From Multiple Contraints, Greg S. Jeong
A Multi-Objective Approach To A Bipartite Assignment Matching Problem Using Weighted Values From Multiple Contraints, Greg S. Jeong
Theses and Dissertations
US Air Force recruiters routinely assign new recruits to available jobs every month. The goal is to find the best assignments in an efficient manner. Although this problem is modeled as a bipartite assignment matching problem, it is not new to the field of Operations Research. This research presents a new approach to solve assignment matching problems given multiple side constraints. Using two multi-criteria optimization techniques, lexicographic optimization and the elastic constraint method, the assignment matching algorithm efficiently produces an optimal solution in a fraction of the time currently spent. This approach is demonstrated in assigning new USAF recruits to …
Screening And Sufficiency In Multiobjective Decision Problems With Large Alternative Sets, Michael D. Cote
Screening And Sufficiency In Multiobjective Decision Problems With Large Alternative Sets, Michael D. Cote
Theses and Dissertations
Portfolio selection problems with combinatorially-large alternative sets can be impossible to evaluate precisely on a reasonable timescale. When portfolios require complex modeling for performance assessment, prohibitive computational processing times can result. Eliminating a small number of alternatives through an intelligent screening process can greatly reduce the number of alternative combinations, thereby decreasing a problem's evaluation time and cost. A methodology was developed for the class of hierarchical portfolio selection problems in which multiple objectives are all judged on the same sub-objectives. First, a novel capability-based alternative screening process was devised to identify and remove poor alternatives, thereby reducing the number …
An Evaluation Of Compressed Work Schedules And Their Impact On Electricity Use, Ryan R. Archambault-Miliner
An Evaluation Of Compressed Work Schedules And Their Impact On Electricity Use, Ryan R. Archambault-Miliner
Theses and Dissertations
As the largest energy consumer in the United States, the Department of Defense must consider all fiscally responsible means to improve energy efficiency. Budgetary and environmental concerns are a catalyst for numerous initiatives designed to reduce energy consumption. Congressional mandates outline the rate at which agencies must reduce facility energy use. In this study, Monte Carlo simulation was used to compare electricity consumption, cost, and emissions produced under 5-day workweeks and compressed work schedules. The research provides energy managers a template for evaluating compressed work schedules as a means to improve energy efficiency. The study found the relationship between the …
Assessing The Economic And Environmental Impacts Associated With Current Street Lighting Technologies, Carlos J. Colon Jr.
Assessing The Economic And Environmental Impacts Associated With Current Street Lighting Technologies, Carlos J. Colon Jr.
Theses and Dissertations
Rising global energy demand and natural disasters continuously threaten energy supplies and prices. As a result, the U.S. government has mandated all government agencies to reduce energy consumption in order to minimize dependence on foreign energy supply and reduce costs. Concern over carbon emissions and environmental impacts has also been expressed in these mandates. One solution may be to invest in newer lighting technologies, such as light-emitting diode (LED) and electrodeless induction, in order to reduce the energy consumption, environmental impact, and costs required for both exterior roadway and parking lot lighting applications. This research compared these lighting technologies with …