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Articles 451 - 480 of 612
Full-Text Articles in Engineering
Machine Learning Models Of C-17 Specific Range Using Flight Recorder Data, Marcus Catchpole
Machine Learning Models Of C-17 Specific Range Using Flight Recorder Data, Marcus Catchpole
Theses and Dissertations
Fuel is a significant expense for the Air Force. The C-17 Globemaster eet accounts for a significant portion. Estimating the range of an aircraft based on its fuel consumption is nearly as old as flight itself. Consideration of operational energy and the related consideration of fuel efficiency is increasing. Meanwhile machine learning and data-mining techniques are on the rise. The old question, "How far can my aircraft y with a given load cargo and fuel?" has given way to "How little fuel can I load into an aircraft and safely arrive at the destination?" Specific range is a measure of …
Improved Fabrication For Micromirror Arrays, Enoc Flores
Improved Fabrication For Micromirror Arrays, Enoc Flores
Theses and Dissertations
Micromirror devices which consisted of one SU-8 2050 layer, two different exposures, and a series of metal depositions were constructed and evaluated. By varying the exposure, a micromirror structure was fabricated with different thicknesses, a ratio of 1.083 µm/(mJ/cm2) was found. The initial design consisted of four layers. The pillar was made of one SU-8 layer, and the top portion had three layers in the following order: gold, SU-8, and gold. This design could not be released and did not have characteristics of a flat and conformal reflective surface. Several variations of the initial design were explored and all of …
Machine Translation With Image Context From Mandarin Chinese To English, Brooke E. Johnson
Machine Translation With Image Context From Mandarin Chinese To English, Brooke E. Johnson
Theses and Dissertations
Despite ongoing improvements in machine translation, machine translators still lack the capability of incorporating context from which source text may have been derived. Machine translators use text from a source language to translate it into a target language without observing any visual context. This work aims to produce a neural machine translation model that is capable of accepting both text and image context as a multimodal translator from Mandarin Chinese to English. The model was trained on a small multimodal dataset of 700 images and sentences, and compared to a translator trained only on the text associated with those images. …
Examining Effectiveness Of Web-Based Internet Of Things Honeypots, Lukas A. Stafira
Examining Effectiveness Of Web-Based Internet Of Things Honeypots, Lukas A. Stafira
Theses and Dissertations
The Internet of Things (IoT) is growing at an alarming rate. It is estimated that there will be over 25 billion IoT devices by 2020. The simplicity of their function usually means that IoT devices have low processing power, which prevent them from having intricate security features, leading to vulnerabilities. This makes IoT devices the prime target of attackers in the coming years. Honeypots are intentionally vulnerable machines that run programs which appear as a vulnerable device to a would-be attacker. They are placed on a network to entice and trap an attacker and then gather information on them, including …
Confidence Inference In Defensive Cyber Operator Decision Making, Graig S. Ganitano
Confidence Inference In Defensive Cyber Operator Decision Making, Graig S. Ganitano
Theses and Dissertations
Cyber defense analysts face the challenge of validating machine generated alerts regarding network-based security threats. Operations tempo and systematic manpower issues have increased the importance of these individual analyst decisions, since they typically are not reviewed or changed. Analysts may not always be confident in their decisions. If confidence can be accurately assessed, then analyst decisions made under low confidence can be independently reviewed and analysts can be offered decision assistance or additional training. This work investigates the utility of using neurophysiological and behavioral correlates of decision confidence to train machine learning models to infer confidence in analyst decisions. Electroencephalography …
A Quantitative Analysis Of The Fusion Of 3-D Scanning Lidar Systems And 2-D Imaging Systems, Michael F. Milton Jr.
A Quantitative Analysis Of The Fusion Of 3-D Scanning Lidar Systems And 2-D Imaging Systems, Michael F. Milton Jr.
Theses and Dissertations
This research will demonstrate the feasibility of fusing the superior spatial resolution of a 2-D imaging system with the precise range to target information of a 3-D imaging system to create a LIDAR imaging system that can accurately find what and where a target is. The 3-D imaging system will use a scanning method as opposed to a flash method that has been used in similar research. The goal of this research is to improve performance of scanning LIDAR so it has better spatial resolution. The research in this thesis proves that incorporating 2-D imaging data into 3-D scanning LIDAR …
Displacement Damage Effects In Gesn Light Emitting Diodes, Kevin K. Choe
Displacement Damage Effects In Gesn Light Emitting Diodes, Kevin K. Choe
Theses and Dissertations
Potential future use on Earth-orbiting satellites calls for investigation into the suitability of GeSn based photonic devices in high energy proton environments. The electroluminescence (EL) intensity of Ge1-xSnx (x = 0, 0.02, 0.069, and 0.094) light emitting diodes was measured before and after irradiation by 2 MeV protons at relatively high fluence levels. The results showed that GeSn devices with higher Sn content were up to 10 times more resistant against proton displacement damage than the pure Ge (x = 0) devices. As Sn concentration increased, the band gap decreased, and V-P hole trap energy level moved further from the …
High Resolution Low-Bandwidth Real-Time Reconnaissance Using Structure From Motion With Planar Homography Estimation, Christian M.A. Arnold
High Resolution Low-Bandwidth Real-Time Reconnaissance Using Structure From Motion With Planar Homography Estimation, Christian M.A. Arnold
Theses and Dissertations
Aerial real-time surveillance exists in a paradigm balancing the constraints of delivering high quality data and transporting data quickly. Typically, to have more of one, sacrifices must be made to the other. This is true of the environment in which an Unmanned Aerial Vehicle (UAV) operates, where real-time communication may be done through a low-bandwidth satellite connection resulting in low-resolution data, and serves as the primary limiting factor in all intelligence operations. Through the use of efficient computer vision techniques, we propose a new Structure from Motion (SfM) method capable of compressing high-resolution data, and delivering that data in real-time. …
Cyber-Attack Drone Payload Development And Geolocation Via Directional Antennae, Clint M. Bramlette
Cyber-Attack Drone Payload Development And Geolocation Via Directional Antennae, Clint M. Bramlette
Theses and Dissertations
The increasing capabilities of commercial drones have led to blossoming drone usage in private sector industries ranging from agriculture to mining to cinema. Commercial drones have made amazing improvements in flight time, flight distance, and payload weight. These same features also offer a unique and unprecedented commodity for wireless hackers -- the ability to gain ‘physical’ proximity to a target without personally having to be anywhere near it. This capability is called Remote Physical Proximity (RPP). By their nature, wireless devices are largely susceptible to sniffing and injection attacks, but only if the attacker can interact with the device via …
Serious Game Design Using Mda And Bloom’S Taxonomy, Senobio V. Chavez
Serious Game Design Using Mda And Bloom’S Taxonomy, Senobio V. Chavez
Theses and Dissertations
The field of Serious Games (SG) studies the use of games as a learning tool and it has been in existence for over forty years. During this period the primary focus of the field has been designing systems to evaluate the educational efficacy of existing games. This translates to a lack of systems designed to aid in the creation of serious games, but this does not have to remain an issue. The rise in popularity of games means that there is no shortage of ideas on how to methodically create them for commercial production which can just as easily be …
Modeling A Consortium-Based Distributed Ledger Network With Applications For Intelligent Transportation Infrastructure, Luis A. Cintron
Modeling A Consortium-Based Distributed Ledger Network With Applications For Intelligent Transportation Infrastructure, Luis A. Cintron
Theses and Dissertations
Emerging distributed-ledger networks are changing the landscape for environments of low trust among participating entities. Implementing such technologies in transportation infrastructure communications and operations would enable, in a secure fashion, decentralized collaboration among entities who do not fully trust each other. This work models a transportation records and events data collection system enabled by a Hyperledger Fabric blockchain network and simulated using a transportation environment modeling tool. A distributed vehicle records management use case is shown with the capability to detect and prevent unauthorized vehicle odometer tampering. Another use case studied is that of vehicular data collected during the event …
Near Real-Time Rf-Dna Fingerprinting For Zigbee Devices Using Software Defined Radios, Frankie A. Cruz
Near Real-Time Rf-Dna Fingerprinting For Zigbee Devices Using Software Defined Radios, Frankie A. Cruz
Theses and Dissertations
Low-Rate Wireless Personal Area Network(s) (LR-WPAN) usage has increased as more consumers embrace Internet of Things (IoT) devices. ZigBee Physical Layer (PHY) is based on the Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 specification designed to provide a low-cost, low-power, and low-complexity solution for Wireless Sensor Network(s) (WSN). The standard’s extended battery life and reliability makes ZigBee WSN a popular choice for home automation, transportation, traffic management, Industrial Control Systems (ICS), and cyber-physical systems. As robust and versatile as the standard is, ZigBee remains vulnerable to a myriad of common network attacks. Previous research involving Radio Frequency-Distinct Native Attribute …
Unguided Cyber Education Techniques Of The Non-Expert, Seth A. Martin
Unguided Cyber Education Techniques Of The Non-Expert, Seth A. Martin
Theses and Dissertations
The United States Air Force and Department of Defense continues to rely on its total workforce to provide the first layer of protection against cyber intrusion. Prior research has shown that the workforce is not adequately educated to perform this task. As a result, DoD cybersecurity strategy now includes attempting to improve education and training on cyber-related concepts and technical skills to all users of DoD networks. This paper describes an experiment designed to understand the broad methods that non-expert users may use to educate themselves on how to perform technical tasks. Preliminary results informed subsequent experiments that directly compared …
Micro-Contacts With 3-D Surfaces Made With Grayscale Lithography, Paul L.J. Michaud
Micro-Contacts With 3-D Surfaces Made With Grayscale Lithography, Paul L.J. Michaud
Theses and Dissertations
MEMS switches show advantages over FET transistors and PIN diodes for switching applications due to low contact resistance, high linearity, low power use, better isolation and lower insertion loss. The switches have not replaced FETs or PIN diodes due to perceived limitations in their reliability and the need for stable contact resistance. In order to create switches acceptable for industry applications, research on micro-contact physics and failure mechanisms of micro-contacts is necessary to develop durable contact surfaces. The aim of this research was to design and fabricate micro-contacts with three-dimensional surfaces using grayscale lithography. The goal was to create devices …
A Multi-Vehicle Cooperative Localization Approach For An Autonomy Framework, Edwin A. Mora
A Multi-Vehicle Cooperative Localization Approach For An Autonomy Framework, Edwin A. Mora
Theses and Dissertations
Offensive techniques produced by technological advancement present opportunities for adversaries to threaten the operational advantages of our joint and allied forces. Combating these new methodologies requires continuous and rapid development towards our own set of \game-changing" technologies. Through focused development of unmanned systems and autonomy, the Air Force can strive to maintain its technological superiority. Furthermore, creating a robust framework capable of testing and evaluating the principles that define autonomy allows for the exploration of future capabilities. This research presents development towards a hybrid reactive/deliberative architecture that will allow for the testing of the principles of task, cognitive, and peer …
A Blockchain-Based Anomalous Detection System For Internet Of Things Devices, Joshua K. Mosby
A Blockchain-Based Anomalous Detection System For Internet Of Things Devices, Joshua K. Mosby
Theses and Dissertations
Internet of Things devices are highly susceptible to attack, and owners often fail to realize they have been compromised. This thesis describes an anomalous-based intrusion detection system that operates directly on Internet of Things devices utilizing a custom-built Blockchain. In this approach, an agent on each node compares the node's behavior to that of its peers, generating an alert if they are behaving differently. An experiment is conducted to determine the effectiveness at detecting malware. Three different code samples simulating common malware are deployed against a testbed of 12 Raspberry Pi devices. Increasing numbers are infected until two-thirds of the …
Direct Path Interference Suppression And Received Signal Processing For Ofdm Passive Radar, Aileen Nundu
Direct Path Interference Suppression And Received Signal Processing For Ofdm Passive Radar, Aileen Nundu
Theses and Dissertations
Passive bistatic radar (PBR) is a fairly active area of research due to the opportunities offered by the ability to use emitters of opportunity for target detection and tracking as well as Synthetic Aperture Radar (SAR) imaging. There is an increasing variety and availability of signals that can be exploited for passive radar and there is also the advantage of angular diversity offered by the bistatic geometry and the potential for stealth operations afforded a passive receiver. Notwithstanding its merits, PBR is complicated by the inevitable presence of Direct Path Interference (DPI) from the transmitter to the receiver, which can …
Analysis Of Satellite Timing And Navigation Receiver Pseudorange Biases Due To Spreading Code Puncturing And Phase Optimized Constant Envelope Transmission, Nathaniel J. Raquet
Analysis Of Satellite Timing And Navigation Receiver Pseudorange Biases Due To Spreading Code Puncturing And Phase Optimized Constant Envelope Transmission, Nathaniel J. Raquet
Theses and Dissertations
There is a desire for future GPS satellites to be software-defined to enable greater operational flexibility and adapt to a variety of current and future threats. This includes implementing new modulation techniques such as phase optimized constant envelope transmission (POCET) and asymmetric signal authentication methods such as chips message robust authentication (Chimera). Any new GPS signal transmitted must be backwards compatible with the millions of receivers already in use. This thesis shows a variety of tests performed to demonstrate the effects of Chimera and POCET-enabled signals. It is shown through actual radio frequency signal generation, testing the response of current-generation …
Characterization Of Metal Contacts On Hydrothermally Synthesized Uranium Dioxide For Novel Semiconductor Applications, Tory E. Robinson
Characterization Of Metal Contacts On Hydrothermally Synthesized Uranium Dioxide For Novel Semiconductor Applications, Tory E. Robinson
Theses and Dissertations
This research is focused on determining which metals or combinations of metals form effective electrical contacts on hydrothermally synthesized UO2 substrates to allow for additional work in characterization of the material as well as the feasibility of its use in semiconductor devices such as solid-state neutron detectors. A methodology was established for selection of candidate metals. Target mixtures composed of Au, Ag, Pt, and Mg were chosen along with several single-metals. Thin metal films were deposited onto tungsten probe tips and hydrothermally synthesized UO2 samples to allow for analysis of mechanical and deposited contact to the substrates through I-V measurements.
A Framework For Cyber Vulnerability Assessments Of Infiniband Networks, Daryl W. Schmitt
A Framework For Cyber Vulnerability Assessments Of Infiniband Networks, Daryl W. Schmitt
Theses and Dissertations
InfiniBand is a popular Input/Output interconnect technology used in High Performance Computing clusters. It is employed in over a quarter of the world’s 500 fastest computer systems. Although it was created to provide extremely low network latency with a high Quality of Service, the cybersecurity aspects of InfiniBand have yet to be thoroughly investigated. The InfiniBand Architecture was designed as a data center technology, logically separated from the Internet, so defensive mechanisms such as packet encryption were not implemented. Cyber communities do not appear to have taken an interest in InfiniBand, but that is likely to change as attackers branch …
Motivating Airmen To Engage With Technical Education: Experimentation And Analysis Using Modern Gamification Techniques, Landon G.M. Tomcho
Motivating Airmen To Engage With Technical Education: Experimentation And Analysis Using Modern Gamification Techniques, Landon G.M. Tomcho
Theses and Dissertations
The development and integration of computer systems into today’s society and the subsequent growth of cyber as a warfighting domain has led to changes in military and civilian conflict. Several traits unique to cyber, including disruption and fast pace of change, has led to issues never before seen in the military environment, especially with educating and training. A new approach that leverages crowd-sourced content has been proposed. This approach relies on motivating military members to voluntarily engage with technical (cyber) education. The application of gamification, a design practice aimed at increasing user engagement by targeting core motivators in humans, in …
Two-On-One Pursuit With A Non-Zero Capture Radius, Patrick J. Wasz
Two-On-One Pursuit With A Non-Zero Capture Radius, Patrick J. Wasz
Theses and Dissertations
In this paper, we revisit the "Two Cutters and Fugitive Ship" differential game that was addressed by Isaacs, but move away from point capture. We consider a two-on-one pursuit-evasion differential game with simple motion and pursuers endowed with circular capture sets of radius l > 0. The regions in the state space where only one pursuer effects the capture and the region in the state space where both pursuers cooperatively and isochronously capture the evader are characterized, thus solving the Game of Kind. Concerning the Game of Degree, the algorithm for the synthesis of the optimal state feedback strategies of the …
Computational And Experimental Development Of 2d Anisotropic Photonic Crystal Metamaterials, James A. Ethridge
Computational And Experimental Development Of 2d Anisotropic Photonic Crystal Metamaterials, James A. Ethridge
Theses and Dissertations
The future of optical devices involves manipulation of nanoscale structure in order to achieve full control over the properties of the device. In fields as diverse as directed energy, remote sensing, optical communications and optical computing, these devices promise to greatly improve performance and efficiency. To advance this further, novel samples that incorporate both photonic crystal (PhC) structure and metamaterial properties, known as PhC metamaterials, are proposed. These PhC metamaterials allow for complete control over the directionality of the light-matter interaction to serve in these new applications. To develop this technology, first, metamaterials with no PhC structure are fabricated using …
Performance Analysis Of Angle Of Arrival Algorithms Applied To Radiofrequency Interference Direction Finding, Taylor S. Barber
Performance Analysis Of Angle Of Arrival Algorithms Applied To Radiofrequency Interference Direction Finding, Taylor S. Barber
Theses and Dissertations
Radiofrequency (RF) interference threatens the functionality of systems that increasingly underpin the daily function of modern society. In recent years there have been multiple incidents of intentional RF spectrum denial using terrestrial interference sources. Because RF based systems are used in safety-of-life applications in both military and civilian contexts, there is need for systems that can quickly locate these interference sources. In order to meet this need, the Air Force Research Laboratory Weapons Directorate is sponsoring the following research to support systems that will be able to quickly geolocate RF interferers using passive angle-of-arrival estimation to triangulate interference sources. This …
High Fidelity Satellite Navigation Receiver Front-End For Advanced Signal Quality Monitoring And Authentication, Andrew D. Braun
High Fidelity Satellite Navigation Receiver Front-End For Advanced Signal Quality Monitoring And Authentication, Andrew D. Braun
Theses and Dissertations
Over the last several years, interest in utilizing foreign satellite timing and navigation (satnav) signals to augment GPS has grown. Doing so is not without risks; foreign satnav signals must be vetted and determined to be trustworthy before use in military applications. Advanced signal quality monitoring methods can help to ensure that only authentic and reliable satnav signals are utilized. To effectively monitor and authenticate signals, the front-end must impress as little distortions upon the received signal as possible. The purpose of this study is to design, fabricate, and test the performance of a high-fidelity satnav receiver front-end for advanced …
Designing Liquid Crystal For Optoacoustic Detection, Michael T. Dela Cruz
Designing Liquid Crystal For Optoacoustic Detection, Michael T. Dela Cruz
Theses and Dissertations
This research impacts the development of a cost-saving, on-chip device that can replace a wide range of costly, bulky sensors for commercial and defense applications. In particular, the goals of this work were to design and test a sensor that uses the optical properties of liquid crystal (LC) to detect acoustic waves. This began with developing a method to fine-tune the optical features of the liquid crystal. Statistical analysis of select experimental variables, or factors, lead to ideal settings of those variables when creating the sensor. A two-factor and three-factor experiment were separately conducted and analyzed as a preliminary demonstration …
A Focal Plane Array And Electronics Model For Cmos And Ccd Sensors In The Afit Sensor And Scene Emulation Tool (Asset), Fernando D. Fernandez
A Focal Plane Array And Electronics Model For Cmos And Ccd Sensors In The Afit Sensor And Scene Emulation Tool (Asset), Fernando D. Fernandez
Theses and Dissertations
Electro-optical and infrared (EO/IR) sensor models are useful tools that can facilitate understanding a system's behavior without expensive and time-consuming testing of an actual system. EO/IR models are especially important to the military industry where truth data is required but is sometimes impractical to obtain through experimentation due to expense or difficulties in procuring hardware. This work describes implementation of a focal plane array (FPA) model of charge-coupled device (CCD) and complementary metal-oxide semiconductor (CMOS) photodetectors as a component in the Air Force Institute of Technology (AFIT) Sensor and Scene Emulation Tool (ASSET). The FPA model covers conversion of photo-generated …
Side Channel Anomaly Detection In Industrial Control Systems Using Physical Characteristics Of End Devices, Ryan D. Harris
Side Channel Anomaly Detection In Industrial Control Systems Using Physical Characteristics Of End Devices, Ryan D. Harris
Theses and Dissertations
Industrial Control Systems (ICS) are described by the Department of Homeland Security as systems that are so \vital to the United States that their incapacity or destruction would have a debilitating impact on our physical or economic security." Attacks like Stuxnet show that these systems are vulnerable. The end goal for Stuxnet was to spin centrifuges at a frequency rate outside of normal operation and hide its activity from the ICS operator. This research aims to provide a proof of concept for an anomaly detection system that would be able to detect an attack like Stuxnet by measuring the physical …
Preserving Privacy In Automotive Tire Pressure Monitoring Systems, Kenneth L. Hacker
Preserving Privacy In Automotive Tire Pressure Monitoring Systems, Kenneth L. Hacker
Theses and Dissertations
The automotive industry is moving towards a more connected ecosystem, with connectivity achieved through multiple wireless systems. However, in the pursuit of these technological advances and to quickly satisfy requirements imposed on manufacturers, the security of these systems is often an afterthought. It has been shown that systems in a standard new automobile that one would not expect to be vulnerable can be exploited for a variety of harmful effects. This thesis considers a seemingly benign, but government mandated, safety feature of modern vehicles; the Tire Pressure Monitoring System (TPMS). Typical implementations have no security-oriented features, leaking data that can …
Electromagnetic Characterization Of Conductor-Backed Media Using Stepped Rectangular Waveguide, Avian Y. Hughes
Electromagnetic Characterization Of Conductor-Backed Media Using Stepped Rectangular Waveguide, Avian Y. Hughes
Theses and Dissertations
A new single stepped-iris waveguide technique is used to nondestructively determine the permittivity and permeability of conductor-backed media. This thesis will demonstrate a proof-of-concept that obtains two independent reflection measurements with a magnetic radar absorbing material (magRAM). Using a two measurement procedure, in which, the first measurement will apply a single rectangular waveguide to a known conductor-backed absorbing material under test (MUT) and the second measurement will insert a stepped-iris in between the single rectangular waveguide and MUT reducing the aperture to retrieve two independent electromagnetic properties (i.e. permittivity and permeability). The theoretical reflection coefficients are obtained using a rigorous …