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Articles 6511 - 6540 of 11510
Full-Text Articles in Engineering
Using Rf-Dna Fingerprints To Discriminate Zigbee Devices In An Operational Environment, Clay K. Dubendorfer
Using Rf-Dna Fingerprints To Discriminate Zigbee Devices In An Operational Environment, Clay K. Dubendorfer
Theses and Dissertations
This research was performed to expand AFIT's Radio Frequency Distinct Native Attribute (RF-DNA) fingerprinting process to support IEEE 802.15.4 ZigBee communication network applications. Current ZigBee bit-level security measures include use of network keys and MAC lists which can be subverted through interception and spoofing using open-source hacking tools. This work addresses device discrimination using Physical (PHY) waveform alternatives to augment existing bit-level security mechanisms. ZigBee network vulnerability to outsider threats was assessed using Receiver Operating Characteristic (ROC) curves to characterize both Authorized Device ID Verification performance (granting network access to authorized users presenting true bit-level credentials) and Rogue Device Rejection …
Cognitive Augmentation For Network Defense, James E. Emge
Cognitive Augmentation For Network Defense, James E. Emge
Theses and Dissertations
Traditionally, when a task is considered for automation it is a binary decision, either the task was completely automated or it remains manual. LOA is a departure from the tradition use of automation in cyber defense. When a task is automated, it removes the human administrator from the performance of the task, compromising their SA of the state of the network. When the administrator loses SA of the network performance and its current state, failure recovery time becomes much longer. This is because the administrators must orient themselves to the current state of the network at the time of failure …
Rootkit Detection Using A Cross-View Clean Boot Method, Bridget N. Flatley
Rootkit Detection Using A Cross-View Clean Boot Method, Bridget N. Flatley
Theses and Dissertations
In cyberspace, attackers commonly infect computer systems with malware to gain capabilities such as remote access, keylogging, and stealth. Many malware samples include rootkit functionality to hide attacker activities on the target system. After detection, users can remove the rootkit and associated malware from the system with commercial tools. This research describes, implements, and evaluates a clean boot method using two partitions to detect rootkits on a system. One partition is potentially infected with a rootkit while the other is clean. The method obtains directory listings of the potentially infected operating system from each partition and compares the lists to …
Automatic Modulation Classification Of Common Communication And Pulse Compression Radar Waveforms Using Cyclic Features, John A . Hadjis
Automatic Modulation Classification Of Common Communication And Pulse Compression Radar Waveforms Using Cyclic Features, John A . Hadjis
Theses and Dissertations
This research develops a feature-based MAP classification system and applies it to classify several common pulse compression radar and communication modulations. All signal parameters are treated as unknown to the classifier system except SNR and the signal carrier frequency. The features are derived from estimated duty cycle, cyclic spectral correlation, and cyclic cumulants. The modulations considered in this research are BPSK, QPSK, 16-QAM, 64-QAM, 8-PSK, and 16-PSK communication modulations, as well as Barker coded, Barker coded, Barker coded, Frank coded, Px49 coded, and LFM pulse compression modulations. Simulations show that average correct signal modulation type classification %C 90% is achieved …
All-Optical Logic Gates And Wavelength Conversion Via The Injection-Locking Of A Fabry-Perot Semiconductor Laser, Evan P. Harvey
All-Optical Logic Gates And Wavelength Conversion Via The Injection-Locking Of A Fabry-Perot Semiconductor Laser, Evan P. Harvey
Theses and Dissertations
This work investigates the implementation of all-optical wavelength conversion and logic gates based on optical injection locking (OIL). All-optical inverting, NOR, and NAND gates are experimentally demonstrated using two distributed feedback (DFB) lasers, a multi-mode Fabry-Perot laser diode (MMFP-LD), and a optical band-pass filter (BPF). The DFB lasers are externally modulated to represent logic inputs into the cavity of the MMFP-LD slave laser. The master lasers' wavelengths are aligned with the longitudinal modes of the MMFP-LD slave laser and their optical power is used to modulate the injection conditions in the slave laser. The optical BPF is used to select …
Improving Bandwidth Utilization In A 1 Tbps Airborne Mimo Communications Downlink, Jonathan D. Hill
Improving Bandwidth Utilization In A 1 Tbps Airborne Mimo Communications Downlink, Jonathan D. Hill
Theses and Dissertations
FEC techniques are compared for different MIMO configurations of a high altitude, extremely wide bandwidth radio frequency downlink. Monte Carlo simulations are completed in MATLAB® with the aim of isolating the impacts of turbo codes and LDPC codes on system throughput and error performance. The system is modeled as a transmit-only static array at an altitude of 60,000 feet, with no interferers in the channel. Transmissions are received by a static receiver array. Simulations attempt to determine what modulation types should be considered for practical implementation, and what FEC codes enable these modulation schemes. The antenna configurations used in this …
Information Encoding On A Pseudo Random Noise Radar Waveform, Joshua A . Hardin
Information Encoding On A Pseudo Random Noise Radar Waveform, Joshua A . Hardin
Theses and Dissertations
Navigation requires knowledge of current location and a planned destination. This is true with manned vehicles and unmanned vehicles. There are many ways to acquire the current location, including global positioning system (GPS), triangulation, radar, and dead reckoning. Today GPS is the most reliable and accurate navigation technique when there is a clear, unobstructed view of the satellite constellation. Various sensors can be used to perform indoor navigation; however, when the vehicle is autonomous the sensors need to provide the exact location to the system. This research determined if using a template replay strategy has the same RNR performance as …
Development Of A Response Planner Using The Uct Algorithm For Cyber Defense, Michael P. Knight
Development Of A Response Planner Using The Uct Algorithm For Cyber Defense, Michael P. Knight
Theses and Dissertations
A need for a quick response to cyber attacks is a prevalent problem for computer network operators today. There is a small window to respond to a cyber attack when it occurs to prevent significant damage to a computer network. Automated response planners offer one solution to resolve this issue. This work presents Network Defense Planner System (NDPS), a planner dependent on the effectiveness of the detection of the cyber attack. This research first explores making classification of network attacks faster for real-time detection, the basic function Intrusion Detection System (IDS) provides. After identifying the type of attack, learning the …
Rf Emitter Tracking And Intent Assessment, Benjamin J. Kuhar
Rf Emitter Tracking And Intent Assessment, Benjamin J. Kuhar
Theses and Dissertations
Current research in employing pattern recognition techniques in a wireless sensor network (WSN) to detect anomalous or suspicious behavior is limited. The purpose of this research was to determine the feasibility of an accurate tracking and intent assessment system of unknown or foreign radio frequency (RF) emitters in close proximity to and within military installations as a method for physical security. 22 position tracks were collected using a hand-held Global Positioning System (GPS) unit and a training data set from five different features was generated for each position track. Each collected position track was individually classified as suspicious or non-suspicious …
Sensitivity Analysis Of An Automated Calibration Routine For Airborne Cameras, Philip E. Lorenzini
Sensitivity Analysis Of An Automated Calibration Routine For Airborne Cameras, Philip E. Lorenzini
Theses and Dissertations
Given a known aircraft location, a set of camera calibration parameters can be used to correlate features in an image with ground locations. Previously, these calibration parameters were obtained during preflight with a lengthy calibration process. A method to automate this calibration using images taken with an aircraft mounted camera and position and attitude data is developed. This thesis seeks to determine a partial set of circumstances that affect the accuracy of the calibration results through simulation and experimental flight test. A software simulator is developed in which to test an array of aircraft maneuvers, camera orientations, and noise injection. …
A Study Of Dim Object Detection For The Space Surveillance Telescope, Stephen D. Maksim
A Study Of Dim Object Detection For The Space Surveillance Telescope, Stephen D. Maksim
Theses and Dissertations
Current methods of dim object detection for space surveillance make use of a Gaussian log-likelihood-ratio-test-based detector that only considers the probability that a single point in an image resulted from the propagation of a point source through space. This paper proposes the application of a correlating Gaussian log-likelihood-ratio-test-based detector, which makes use of all the pixels in the window, to the arena of dim object detection. The requirements for comparing these detectors using the same threshold of detection are established. The performance of the detectors is compared using images taken by the Space Surveillance Telescope in New Mexico of a …
Error Characterization Of Vision-Aided Navigation Systems, Daniel A . Marietta
Error Characterization Of Vision-Aided Navigation Systems, Daniel A . Marietta
Theses and Dissertations
The goal of this work is to characterize the errors committed by an Image Aided Navigation (IAN) algorithm that has been developed for use as a navigation tool in GPS denied areas. The filter under study was developed by the Air Force Institute of Technology's Advanced Navigation Technology center, and has been the focus of numerous research efforts. Unfortunately, these studies have all been based on single runs or simulations, and such results may not be indicative of the true filter performance. This problem extends to IAN publications in general; no analysis of IAN based upon a sizable real world …
Evaluating The Effectiveness Of Ip Hopping Via An Address Routing Gateway, Ryan A . Morehart
Evaluating The Effectiveness Of Ip Hopping Via An Address Routing Gateway, Ryan A . Morehart
Theses and Dissertations
This thesis explores the viability of using Internet Protocol (IP) address hopping in front of a network as a defensive measure. This research presents a custom gateway-based IP hopping solution called Address Routing Gateway (ARG) that acts as a transparent IP address hopping gateway. This thesis tests the overall stability of ARG, the accuracy of its classifications, the maximum throughput it can support, and the maximum rate at which it can change IPs and still communicate reliably. This research is accomplished on a physical test network with nodes representing the types of hosts found on a typical, corporate-style network. Direct …
An Architecture For Coexistence With Multiple Users In Frequency Hopping Cognitive Radio Networks, Ryan K. Mclean
An Architecture For Coexistence With Multiple Users In Frequency Hopping Cognitive Radio Networks, Ryan K. Mclean
Theses and Dissertations
The radio frequency (RF) spectrum is a limited resource. Spectrum allotment disputes stem from this scarcity as many radio devices are con confined to a fixed frequency or frequency sequence. One alternative is to incorporate cognition within a configurable radio platform, therefore enabling the radio to adapt to dynamic RF spectrum environments. In this way, the radio is able to actively observe the RF spectrum, orient itself to the current RF environment, decide on a mode of operation, and act accordingly, thereby sharing the spectrum and operating in more flexible manner. This research presents a novel framework for incorporating several …
The Miniaturization Of The Afit Random Noise Radar, Aaron T. Myers
The Miniaturization Of The Afit Random Noise Radar, Aaron T. Myers
Theses and Dissertations
Advances in technology and signal processing techniques have opened the door to using an UWB random noise waveform for radar imaging. This unique, low probability of intercept waveform has piqued the interest of the U.S. DoD as well as law enforcement and intelligence agencies alike. While AFIT's noise radar has made significant progress, the current architecture needs to be redesigned to meet the space constraints and power limitations of an aerial platform. This research effort is AFIT's first attempt at RNR miniaturization and centers on two primary objectives: 1) identifying a signal processor that is compact, energy efficient, and capable …
Inertial Navigation System Aiding Using Vision, James O. Quarmyne
Inertial Navigation System Aiding Using Vision, James O. Quarmyne
Theses and Dissertations
The aiding of an INS using measurements over time of the line of sight of ground features as they come into view of an onboard camera is investigated. The objective is to quantify the reduction in the navigation states' errors by using bearings-only measurements over time of terrain features in the aircraft's field of view. INS aiding is achieved through the use of a Kalman Filter. The design of the Kalman Filter is presented and it is shown that during a long range, wings level cruising flight at constant velocity and altitude, a 90% reduction in the aided INS-calculated navigation …
Modeling Cyber Situational Awareness Through Data Fusion, Evan L. Raulerson
Modeling Cyber Situational Awareness Through Data Fusion, Evan L. Raulerson
Theses and Dissertations
Cyber attacks are compromising networks faster than administrators can respond. Network defenders are unable to become oriented with these attacks, determine the potential impacts, and assess the damages in a timely manner. Since the observations of network sensors are normally disjointed, analysis of the data is overwhelming and time is not spent efficiently. Automation in defending cyber networks requires a level of reasoning for adequate response. Current automated systems are mostly limited to scripted responses. Better defense tools are required. This research develops a framework that aggregates data from heterogeneous network sensors. The collected data is correlated into a single …
Detection Optimization Of The Progressive Multi-Channel Correlation Algorithm Used In Infrasound Nuclear Treaty Monitoring, Anthony M. Runco
Detection Optimization Of The Progressive Multi-Channel Correlation Algorithm Used In Infrasound Nuclear Treaty Monitoring, Anthony M. Runco
Theses and Dissertations
This thesis develops methods to determine optimum detection thresholds for the Progressive Multi-Channel Correlation (PMCC) algorithm used by the International Data Centre (IDC) to perform infrasound station-level nuclear-event detection. Receiver Operating Characteristic (ROC) curve analysis is used with real ground truth data to determine the trade-off between the probability of detection (P sub D) and the false alarm rate (FAR) at various consistency detection thresholds. Further, statistical detection theory via maximum a posteriori and Bayes cost approaches is used to determine station-level optimum family size thresholds of grouped detection pixels with similar signal attributes (i.e. trace velocity, azimuth, time of …
Characterization And Dynamic Analysis Of Long-Cavity Multi-Section Gain-Levered Quantum-Dot Lasers, John R. Schmidt
Characterization And Dynamic Analysis Of Long-Cavity Multi-Section Gain-Levered Quantum-Dot Lasers, John R. Schmidt
Theses and Dissertations
This research investigates the impact of different device architectures on the frequency response of long-cavity multi-section quantum-dot lasers. This work focused on a novel 8.3-mm multi-section quantum-dot device which possessed the flexibility to be configured either as a single- or multi-section device having gain-to-modulation section ratios of 14:2 and 15:1. The long-cavity device design facilitated the testing of increased gain-to-modulation section length ratios previously unexplored in the context of the gain-lever effect. The investigation of the gain-lever effect showed improvements to both the modulation efficiency and modulation bandwidth of the device under test. The modulation efficiency and modulation bandwidth were …
File Carving And Malware Identification Algorithms Applied To Firmware Reverse Engineering, Karl A . Sickendick
File Carving And Malware Identification Algorithms Applied To Firmware Reverse Engineering, Karl A . Sickendick
Theses and Dissertations
Modern society depends on critical infrastructure (CI) managed by Programmable Logic Controllers (PLCs). PLCs depend on firmware, though firmware security vulnerabilities and contents remain largely unexplored. Attackers are acquiring the knowledge required to construct and install malicious firmware on CI. To the defender, firmware reverse engineering is a critical, but tedious, process. This thesis applies machine learning algorithms, from the le carving and malware identification fields, to firmware reverse engineering. It characterizes the algorithms' performance. This research describes and characterizes a process to speed and simplify PLC firmware analysis. The system partitions binary firmwares into segments, labels each segment with …
Novel Test Fixture For Characterizing Microcontacts: Performance And Reliability, Benjamin F. Toler
Novel Test Fixture For Characterizing Microcontacts: Performance And Reliability, Benjamin F. Toler
Theses and Dissertations
Engineers have attempted to improve reliability and lifecycle performance using novel micro-contact metals, unique mechanical designs and packaging. Contact resistance can evolve over the lifetime of the micro-switch by increasing until failure. This work shows the fabrication of micro-contact support structures and test fixture which allow for micro-contact testing, with an emphasis on the fixture's design to allow the determination and analysis of the appropriate failure mode. The other effort of this investigation is the development of a micro-contact test fixture which can measure contact force and resistance directly and perform initial micro-contact characterization, and two forms of lifecycle testing …
Adaptations And Analysis Of The Afit Noise Radar Network For Indoor Navigation, Russell D. Wilson Iv
Adaptations And Analysis Of The Afit Noise Radar Network For Indoor Navigation, Russell D. Wilson Iv
Theses and Dissertations
After several years of development, the AFIT Noise Radar Network (NoNET) has proven to be an extremely versatile system for many standard radar functions. This pallet of capabilities includes through the wall target tracking capabilities due to its wide bandwidth and UHF operations. Utilizing White Gaussian Noise as its waveform, the NoNET can operate at much lower power levels than other comparable systems while remaining extremely covert. In an effort to explore new applications, the question arose could the NoNET provide a viable option for navigation capability in GPS denied and indoor environments? This research aims to provide proof of …
Urgent Aeromedical Evacuation Network Capacity Planning, Scott C. Finkbeiner
Urgent Aeromedical Evacuation Network Capacity Planning, Scott C. Finkbeiner
Theses and Dissertations
Aeromedical Evacuation (AE) has been steadily utilized during Operation Iraqi Freedom and Operation Enduring Freedom. AE is a global enterprise. The current structure of AE is facing changes as forces scale down from operations in Iraq and Afghanistan. AE will, however, continue to be important in its domestic use in the continental USA (CONUS). Current practice is to pull aircraft (e.g. C-17, C-130 or KC-135) from their normal operations to meet Urgent and Priority patient needs when local alternatives are infeasible. An alternative to the current system would be having a centralized "bed-down" location for AE operations that would house …
A Mixed Integer Programming Model For Improving Theater Distribution Force Flow Analysis, Micah J. Hafich
A Mixed Integer Programming Model For Improving Theater Distribution Force Flow Analysis, Micah J. Hafich
Theses and Dissertations
Obtaining insight into potential vehicle mixtures that will support theater distribution, the final leg of military distribution, can be a challenging and time consuming process for United States Transportation Command (USTRANSCOM) force flow analysts. The current process of testing numerous different vehicle mixtures until separate simulation tools demonstrate feasibility is iterative and overly burdensome. Improving on existing research, a mixed integer programming model was developed to allocate specific vehicle types to delivery items, or requirements, in a manner that would minimize both operational costs and late deliveries. This gives insight into the types and amounts of vehicles necessary for feasible …
Aerial Refueling Simulator Validation Using Operational Experimentation And Response Surface Methods With Time Series Responses, Alexander P. Hillman
Aerial Refueling Simulator Validation Using Operational Experimentation And Response Surface Methods With Time Series Responses, Alexander P. Hillman
Theses and Dissertations
An important program in the Department of Defense is the KC-46 Supertanker. Dubbed the future of the Air Force's aerial refueling inventory, the KC-46 will replace dozens of ailing previous generation tanker aircraft. The Aerial Refueling Airplane Simulator Qualification document governs the methods by which Air Mobility Command validates its simulators, some of which will be KC-46 simulators in the near future. The methodology set forward in this thesis utilizes historical data of aircraft performance from similar air frames to gain statistical insight into the performance design space of the KC-46. Leveraging this insight, the methodology provides through a framework …
Operational Planning Of Channel Airlift Missions Using Forecasted Demand, Taylor J. Leonard
Operational Planning Of Channel Airlift Missions Using Forecasted Demand, Taylor J. Leonard
Theses and Dissertations
Past research proposed that it is possible to forecast cargo demand using time series models and that there exists potential cost savings in the way that Civilian Reserve Air Fleet (CRAF) is used for cargo airlift. United States Transportation Command (USTRANSCOM) performs annual fixed-buys of CRAF to support airlift needs. Forecasted cargo demand would allow for reasonably accurate cargo projections vs. the current expected value estimation. Accurate forecasting allows for greater fixed-buys, further incentivizing CRAF airlines as well as reducing the number of additional aircraft purchases during the quarterly and monthly buys. Multiple forecasting models are constructed and the results …
Estimating The Probability Of Being The Best System: A Generalized Method And Nonparametric Hypothesis Test, Aaron M. Lessin
Estimating The Probability Of Being The Best System: A Generalized Method And Nonparametric Hypothesis Test, Aaron M. Lessin
Theses and Dissertations
This thesis provides two new approaches for comparing competing systems. Instead of making comparisons based on long run averages or mean performance, the first paper presents a generalized method for calculating the probability that a single system is the best among all systems in a single trial. Unlike current empirical methods, the generalized method calculates the exact multinomial probability that a single system is best among competing systems. The ability to avoid time consuming empirical estimate techniques could potentially result in significant savings in both time and money when comparing alternate systems. A Monte Carlo simulation is conducted comparing the …
Control Variates And Optimal Designs In Metamodeling, Joshua B. Meents
Control Variates And Optimal Designs In Metamodeling, Joshua B. Meents
Theses and Dissertations
At the heart of most modeling issues is a focus on variance reduction. Experimental designs are chosen based on both efficiency and a variety of variance based criteria. In many situations due to cost, time and availability issues it is beneficial to produce metamodels of simulations. Experimental designs for the region of operability are constructed to collect the simulation output required to construct representative metamodels. Independently, the method of control variates is a well established technique often employed to reduce variance in discrete event simulations. This thesis explores the variance reduction benefits that can be obtained by combining optimal experimental …
Evaluating Courses Of Actions At The Strategic Planning Level, Alhmet Ozdemir
Evaluating Courses Of Actions At The Strategic Planning Level, Alhmet Ozdemir
Theses and Dissertations
Like almost all real life problems, Strategic planning is a good example of a problem with more than one objective. One of the most important steps of strategic planning is to generate and evaluate the courses of actions (COA) which can fulfill the mission and vision of the organization. This is a critical process since it is impractical to start the executed COA over. In this research, value-focused thinking (VFT) is used as a decision analysis tool to assess COAs. A general model is created to select the best COA for strategic planning such as air force operation planning. To …
An Examination Of Statistical Rigor Infused Into The Kc-46 Flight Test Program, Sean C. Ritter
An Examination Of Statistical Rigor Infused Into The Kc-46 Flight Test Program, Sean C. Ritter
Theses and Dissertations
The KC-46 program is bringing on-line the replacement aircraft for the KC-135. Although not a new development program, but rather a modification program, there are extensive plans for the flight testing of the KC-46. Recent DoD emphasis mandates the use of statistical design principles for DoD test and evaluation. This project will examine the planned flight test program for KC-46 and reconsider components of that program based on principles of statistical rigor. Of particular focus will be the reliability and maintainability aspects of the flight test program. Current methodology assumes a constant failure rate in all situations, implying that the …