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Air Force Institute of Technology

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Aerospace Vehicle Comprising Module For Method Of Terrain, Terrain Activity And Material Classification, Matthew E. Nussbaum, Marissa S. Herron May 2024

Aerospace Vehicle Comprising Module For Method Of Terrain, Terrain Activity And Material Classification, Matthew E. Nussbaum, Marissa S. Herron

AFIT Patents

A method of classifying terrain, terrain activity and materials through panchromatic imagery a module programmed to provide such classification and aerospace vehicles comprising such module is provided. Panchromatic images of known materials terrains and terrain activities are taken and processed to form a multiband texture cube, that due it amount of data, is stored as a computer data base. New panchromatic images of unclassified materials, terrains and/or terrain activities are processed and compared via computer with such database that allows for inexpensive, quick and efficient classification of such new images.


Analysis Of Modeled 3d Solar Magnetic Field During 30 X/M-Class Solar Flares, Seth H. Garland, Vasyl B. Yurchyshyn, Robert D. Loper, Benjamin F. Akers, Daniel J. Emmons Ii May 2024

Analysis Of Modeled 3d Solar Magnetic Field During 30 X/M-Class Solar Flares, Seth H. Garland, Vasyl B. Yurchyshyn, Robert D. Loper, Benjamin F. Akers, Daniel J. Emmons Ii

Faculty Publications

Using non-linear force free field (NLFFF) extrapolation, 3D magnetic fields were modeled from the 12-min cadence Solar Dynamics Observatory Helioseismic and Magnetic Imager (HMI) photospheric vector magnetograms, spanning a time period of 1 hour before through 1 hour after the start of 18 X-class and 12 M-class solar flares. Several magnetic field parameters were calculated from the modeled fields directly, as well as from the power spectrum of surface maps generated by summing the fields along the vertical axis, for two different regions: areas with photospheric |Bz|≥ 300 G (active region—AR) and areas above the photosphere with the …


Quantification Of Surface Layer Turbulence Using Sensible Heat Values From Energy Balance Versus Aerodynamic Methods, Steven T. Fiorino, Yogendra Raut, Jaclyn Schmidt, Laura Slabaugh, Blaine Fourman, Jack E. Mccrae, Benjamin C. Wilson, Santasri R. Bose-Pillai May 2024

Quantification Of Surface Layer Turbulence Using Sensible Heat Values From Energy Balance Versus Aerodynamic Methods, Steven T. Fiorino, Yogendra Raut, Jaclyn Schmidt, Laura Slabaugh, Blaine Fourman, Jack E. Mccrae, Benjamin C. Wilson, Santasri R. Bose-Pillai

Faculty Publications

Surface layer optical turbulence values in the form of the refractive index structure function C_n^2 are often calculated from surface layer temperature, moisture, and wind characteristics and compared to measurements from sonic anemometers, differential temperature sensors, and imaging systems. A key derived component needed in the surface layer turbulence calculations is the sensible heat value. Typically, the sensible heat is calculated using the bulk aerodynamic method that assumes a certain surface roughness and a friction velocity that approximates the turbulence drag on temperature and moisture mixing from the change in the average surface layer vertical wind velocity. These assumptions/approximations generally …


Deterministic Global 3d Fractal Cloud Model For Synthetic Scene Generation, Aaron M. Schinder, Shannon R. Young, Bryan J. Steward, Michael L. Dexter, Andrew Kondrath, Stephen Hinton, Ricardo Davila May 2024

Deterministic Global 3d Fractal Cloud Model For Synthetic Scene Generation, Aaron M. Schinder, Shannon R. Young, Bryan J. Steward, Michael L. Dexter, Andrew Kondrath, Stephen Hinton, Ricardo Davila

Faculty Publications

This paper describes the creation of a fast, deterministic, 3D fractal cloud renderer for the AFIT Sensor and Scene Emulation Tool (ASSET). The renderer generates 3D clouds by ray marching through a volume and sampling the level-set of a fractal function. The fractal function is distorted by a displacement map, which is generated using horizontal wind data from a Global Forecast System (GFS) weather file. The vertical windspeed and relative humidity are used to mask the creation of clouds to match realistic large-scale weather patterns over the Earth. Small-scale detail is provided by the fractal functions which are tuned to …


Investigating Turbulence Distribution In The Lower Atmosphere Using Time-Lapse Imagery From A Camera Bank, Benjamin C. Wilson, Santasri R. Bose-Pillai, Jack E. Mccrae, Steven T. Fiorino, Robert P. Freeman, Laura R. Slabaugh Apr 2024

Investigating Turbulence Distribution In The Lower Atmosphere Using Time-Lapse Imagery From A Camera Bank, Benjamin C. Wilson, Santasri R. Bose-Pillai, Jack E. Mccrae, Steven T. Fiorino, Robert P. Freeman, Laura R. Slabaugh

Faculty Publications

The atmosphere’s surface layer (first 50–100 m above the ground) is extremely dynamic and is influenced by surface radiative properties, roughness, and atmospheric stability. Understanding the distribution of turbulence in the surface layer is critical to many applications, such as directed energy and free space optical communications. Several measurement campaigns in the past have relied on weather balloons or sonic detection and ranging (SODAR) to measure turbulence up to the atmospheric boundary layer. However, these campaigns had limited measurements near the surface. We have developed a time-lapse imaging technique to profile atmospheric turbulence from turbulence-induced differential motion or tilts between …


Deep Selenium Donors In Zngep2 Crystals: An Electron Paramagnetic Resonance Study Of A Nonlinear Optical Material, Timothy D. Gustafson, Larry E. Halliburton, Nancy C. Giles, Peter G. Schunemann, Kevin T. Zawilski, J. Jesenovec, Kent L. Averett, Jonathan E. Slagle [*] Apr 2024

Deep Selenium Donors In Zngep2 Crystals: An Electron Paramagnetic Resonance Study Of A Nonlinear Optical Material, Timothy D. Gustafson, Larry E. Halliburton, Nancy C. Giles, Peter G. Schunemann, Kevin T. Zawilski, J. Jesenovec, Kent L. Averett, Jonathan E. Slagle [*]

Faculty Publications

Zinc germanium diphosphide (ZnGeP2) is a ternary semiconductor best known for its nonlinear optical properties. A primary application is optical parametric oscillators operating in the mid-infrared region. Controlled donor doping provides a method to minimize the acceptor-related absorption bands that limit the output power of these devices. In the present study, a ZnGeP2 crystal is doped with selenium during growth. Selenium substitutes for phosphorus and serves as a deep donor. Significant concentrations of native defects (zinc vacancies, germanium-on-zinc antisites, and phosphorous vacancies) are also present in the crystal. Electron paramagnetic resonance (EPR) is used to establish the …


Nowcasting Solar Euv Irradiance With Photospheric Magnetic Fields And The Mg Ii Index, Kara L. Kniezewski, Samuel J. Schonfeld, Carl J. Henney Apr 2024

Nowcasting Solar Euv Irradiance With Photospheric Magnetic Fields And The Mg Ii Index, Kara L. Kniezewski, Samuel J. Schonfeld, Carl J. Henney

Student Publications

A new method to nowcast spectral irradiance in extreme ultraviolet (EUV) and far ultraviolet (FUV) bands is presented here, utilizing only solar photospheric magnetograms and the Mg II index (i.e., the core-to-wing ratio). The EUV and FUV modeling outlined here is a direct extension of the SIFT (Solar Indices Forecasting Tool) model, based on Henney et al. (2015, https://doi.org/10.1002/2014sw001118). SIFT estimates solar activity indices using the earth-side solar photospheric magnetic field sums from global magnetic maps generated by the ADAPT (Air Force Data Assimilative Photospheric Flux Transport) model. Utilizing strong and weak magnetic field sums from ADAPT maps, Henney …


Pulsed-Power Neutron Production With Deuterated Polymer Accelerator Targets, Anthony O. Hagey, Juan J. Manfredi, Whitman T. Dailey, S. L. Jackson, E. R. Kaiser, J. W. Schumer Apr 2024

Pulsed-Power Neutron Production With Deuterated Polymer Accelerator Targets, Anthony O. Hagey, Juan J. Manfredi, Whitman T. Dailey, S. L. Jackson, E. R. Kaiser, J. W. Schumer

Faculty Publications

This document presents an investigation of the effect of deuterated accelerator targets on the neutron fluence from a local mass injection dense plasma focus (LMIDPF) driven by the United States Naval Research Laboratory's (NRL) Hawk pulsed-power generator. Deuterated targets were made using two methods: a well-established thin-film casting technique for flat targets and a more novel additive manufacturing technique that allowed targets to be three-dimensional (3D) printed in both flat and conical geometries. These targets were then tested during neutron-producing experiments conducted using Hawk, and theneutron fluences measured for the various target types were compared. Additive manufacturing was used as …


Analysis Of Fast-Cured Plastic Scintillator Variations, Andrew K. Nesbitt, John W. Mcclory, Juan J. Manfredi, Andrew W. Decker Apr 2024

Analysis Of Fast-Cured Plastic Scintillator Variations, Andrew K. Nesbitt, John W. Mcclory, Juan J. Manfredi, Andrew W. Decker

Faculty Publications

Organic plastic scintillators are widely used in a variety of homeland security applications, most commonly as detectors for radiation portal monitors due to their relative low cost, physical robustness, and fast-timing properties. However, plastic scintillators also typically provide lower light yields and photon sensitivity compared to other detector material alternatives, so many studies over the past two decades have sought ways to overcome these shortfalls. Research recently conducted at the Air Force Institute of Technology and Oak Ridge National Laboratory demonstrated that photocuring novel plastics offered a viable method for producing fast-curing plastic scintillators (FCPSs). These formulations included an acrylic …


Effect Of Fabrication Parameters On The Ferroelectricity Of Hafnium Zirconium Oxide Films: A Statistical Study, Guillermo A. Salcedo, Ahmad E. Islam, Elizabeth Reichley, Michael Dietz, Christine M. Schubert Kabban, Kevin D. Leedy, Tyson C. Back, Weison Wang, Andrew Green, Timothy S. Wolfe, James M. Sattler Mar 2024

Effect Of Fabrication Parameters On The Ferroelectricity Of Hafnium Zirconium Oxide Films: A Statistical Study, Guillermo A. Salcedo, Ahmad E. Islam, Elizabeth Reichley, Michael Dietz, Christine M. Schubert Kabban, Kevin D. Leedy, Tyson C. Back, Weison Wang, Andrew Green, Timothy S. Wolfe, James M. Sattler

Faculty Publications

Ferroelectricity in hafnium zirconium oxide (Hf1−xZrxO2) and the factors that impact it have been a popular research topic since its discovery in 2011. Although the general trends are known, the interactions between fabrication parameters and their effect on the ferroelectricity of Hf1−xZrxO2 require further investigation. In this paper, we present a statistical study and a model that relates Zr concentration (x), film thickness (tf), and annealing temperature (Ta) with the remanent polarization (Pr) in tungsten (W)-capped Hf1−xZrxO2. …


Study Protocol: Identifying Transcriptional Regulatory Alterations Of Chronic Effects Of Blast And Disturbed Sleep In United States Veterans, Molly J. Sullan, Kelly A. Stearns-Yoder, Zhaoyu Wang, Andrew J. Hoisington, Adam D. Brenoweth, Walter Carr, Yongchao Ge, Hanga Galfalvy, Fatemah Haghighi, Lisa A. Brenner Mar 2024

Study Protocol: Identifying Transcriptional Regulatory Alterations Of Chronic Effects Of Blast And Disturbed Sleep In United States Veterans, Molly J. Sullan, Kelly A. Stearns-Yoder, Zhaoyu Wang, Andrew J. Hoisington, Adam D. Brenoweth, Walter Carr, Yongchao Ge, Hanga Galfalvy, Fatemah Haghighi, Lisa A. Brenner

Faculty Publications

Injury related to blast exposure dramatically rose during post-911 era military conflicts in Iraq and Afghanistan. Mild traumatic brain injury (mTBI) is among the most common injuries following blast, an exposure that may not result in a definitive physiologic marker (e.g., loss of consciousness). Recent research suggests that exposure to low level blasts and, more specifically repetitive blast exposure (RBE), which may be subconcussive in nature, may also impact long term physiologic and psychological outcomes, though findings have been mixed. For military personnel, blast-related injuries often occur in chaotic settings (e.g., combat), which create challenges in the immediate assessment of …


Scriptblock Smuggling: Uncovering Stealthy Evasion Techniques In Powershell And .Net Environments, Anthony J. Rose, Scott R. Graham, Christine M. Schubert, Jacob Krasnov, Wayne C. Henry Mar 2024

Scriptblock Smuggling: Uncovering Stealthy Evasion Techniques In Powershell And .Net Environments, Anthony J. Rose, Scott R. Graham, Christine M. Schubert, Jacob Krasnov, Wayne C. Henry

Faculty Publications

The Antimalware Scan Interface (AMSI) plays a crucial role in detecting malware within Windows operating systems. This paper presents ScriptBlock Smuggling, a novel evasion and log spoofing technique exploiting PowerShell and .NET environments to circumvent the AMSI. By focusing on the manipulation of ScriptBlocks within the Abstract Syntax Tree (AST), this method creates dual AST representations, one for compiler execution and another for antivirus and log analysis, enabling the evasion of AMSI detection and challenging traditional memory patching bypass methods. This research provides a detailed analysis of PowerShell’s ScriptBlock creation and its inherent security features and pinpoints critical limitations in …


The Impact Of Data Preparation And Model Complexity On The Natural Language Classification Of Chinese News Headlines, Torrey J. Wagner, Dennis Guhl, Brent T. Langhals Mar 2024

The Impact Of Data Preparation And Model Complexity On The Natural Language Classification Of Chinese News Headlines, Torrey J. Wagner, Dennis Guhl, Brent T. Langhals

Faculty Publications

Given the emergence of China as a political and economic power in the 21st century, there is increased interest in analyzing Chinese news articles to better understand developing trends in China. Because of the volume of the material, automating the categorization of Chinese-language news articles by headline text or titles can be an effective way to sort the articles into categories for efficient review. A 383,000-headline dataset labeled with 15 categories from the Toutiao website was evaluated via natural language processing to predict topic categories. The influence of six data preparation variations on the predictive accuracy of four algorithms was …


Technical Data Package For Sysmlv2 Vignettes, Allen W. Dukes Mar 2024

Technical Data Package For Sysmlv2 Vignettes, Allen W. Dukes

Student Publications

This Technical Data Package (TDP) thoroughly compiles instructions, concepts, and solutions for eight SysMLv2 vignettes. Each vignette illustrates methods to solve complex system modeling challenges. The initial concept for each vignette can drive the use and evaluation of a custom SysMLv2 modeling tool as shown in [1]. They can support a baseline set of tasks to compare usability with other SysMLv2 modeling software tools.

The document starts with three pairs of vignettes for modeling a hypothetical Unmanned Aerial Vehicle (UAV) operated with a Virtual Reality (VR) headset derived from AFIT WKSP 696. The final pair of vignettes focus on two …


Association Of Blast Exposure In Military Breaching With Intestinal Permeability Blood Biomarkers Associated With Leaky Gut, Qingkun Liu, Zhaoyu Wang, Shengnan Sun, Jeffrey Nemes, Lisa A. Brenner, Miciej Skotak, Christina R. Lavalle, Yongchao Ge, Walter Carr, Fatemeh Haghighi Mar 2024

Association Of Blast Exposure In Military Breaching With Intestinal Permeability Blood Biomarkers Associated With Leaky Gut, Qingkun Liu, Zhaoyu Wang, Shengnan Sun, Jeffrey Nemes, Lisa A. Brenner, Miciej Skotak, Christina R. Lavalle, Yongchao Ge, Walter Carr, Fatemeh Haghighi

Faculty Publications

Injuries and subclinical effects from exposure to blasts are of significant concern in military operational settings, including tactical training, and are associated with self-reported concussion-like symptomology and physiological changes such as increased intestinal permeability (IP), which was investigated in this study. Time-series gene expression and IP biomarker data were generated from “breachers” exposed to controlled, low-level explosive blast during training. Samples from 30 male participants at pre-, post-, and follow-up blast exposure the next day were assayed via RNA-seq and ELISA. A battery of symptom data was also collected at each of these time points that acutely showed elevated symptom …


Laboratory Exercise For The Radiometry Student, Michael A. Marciniak Mar 2024

Laboratory Exercise For The Radiometry Student, Michael A. Marciniak

Faculty Publications

The U.S. Air and Space Forces require optical expertise among their personnel. The Air Force Institute of Technology offers a graduate optics curriculum, which includes a three-course sequence to educate students in the optical concepts of radiometry and radiometric instrumentation. We find radiometry is often a deceptively difficult concept for students to master. To address this, we have developed an experiment in our optics-laboratory coursework to help them gain this mastery. A Fourier-transform infrared spectrometer (FTS) is used to collect spectral data from an unknown sample. FTS calibration and data collection are discussed here, as are the two specific samples …


Relative Vectoring Using Dual Object Detection For Autonomous Aerial Refueling, Derek B. Worth, Jeffrey L. Choate, James Lynch, Scott L. Nykl, Clark N. Taylor Mar 2024

Relative Vectoring Using Dual Object Detection For Autonomous Aerial Refueling, Derek B. Worth, Jeffrey L. Choate, James Lynch, Scott L. Nykl, Clark N. Taylor

Faculty Publications

Once realized, autonomous aerial refueling will revolutionize unmanned aviation by removing current range and endurance limitations. Previous attempts at establishing vision-based solutions have come close but rely heavily on near perfect extrinsic camera calibrations that often change midflight. In this paper, we propose dual object detection, a technique that overcomes such requirement by transforming aerial refueling imagery directly into receiver aircraft reference frame probe-to-drogue vectors regardless of camera position and orientation. These vectors are precisely what autonomous agents need to successfully maneuver the tanker and receiver aircraft in synchronous flight during refueling operations. Our method follows a common 4-stage process …


Random Forests For Detecting Weak Signals And Extracting Physical Information: A Case Study Of Magnetic Navigation, Mohammadamin Moradi, Zheng-Meng Zhai, Aaron Nielsen, Ying-Cheng Lai, Aaron P. Nielsen Mar 2024

Random Forests For Detecting Weak Signals And Extracting Physical Information: A Case Study Of Magnetic Navigation, Mohammadamin Moradi, Zheng-Meng Zhai, Aaron Nielsen, Ying-Cheng Lai, Aaron P. Nielsen

Faculty Publications

It has been recently demonstrated that two machine-learning architectures, reservoir computing and time-delayed feed-forward neural networks, can be exploited for detecting the Earth’s anomaly magnetic field immersed in overwhelming complex signals for magnetic navigation in a GPS-denied environment. The accuracy of the detected anomaly field corresponds to a positioning accuracy in the range of 10–40 m. To increase the accuracy and reduce the uncertainty of weak signal detection as well as to directly obtain the position information, we exploit the machine-learning model of random forests that combines the output of multiple decision trees to give optimal values of the physical …


Seasonal Variability And Predictability Of Monsoon Precipitation In Southern Africa, Matthew F. Horan, Fred Kucharski, Moetasim Ashfaq Mar 2024

Seasonal Variability And Predictability Of Monsoon Precipitation In Southern Africa, Matthew F. Horan, Fred Kucharski, Moetasim Ashfaq

Faculty Publications

Rainfed agriculture is the mainstay of economies across Southern Africa (SA), where most precipitation is received during the austral summer monsoon. This study aims to further our understanding of monsoon precipitation predictability over SA. We use three natural climate forcings, El Niño–Southern Oscillation, Indian Ocean Dipole (IOD), and the Indian Ocean Precipitation Dipole (IOPD)—the dominant precipitation variability mode—to construct an empirical model that exhibits significant skill over SA during monsoon in explaining precipitation variability and in forecasting it with a five-month lead. While most explained precipitation variance (50%–75%) comes from contemporaneous IOD and IOPD, preconditioning all three forcings is key …


Enhancing The Resilience Of Space Systems Against Ransomware Attacks, Petersen F. Hansen Mar 2024

Enhancing The Resilience Of Space Systems Against Ransomware Attacks, Petersen F. Hansen

Theses and Dissertations

As their relevance has increased in recent years, space systems have become nearly essential in modern life. They are integral in the operation of navigational systems, military operations, and have ushered in a new domain of scientific inquiry. Technological advances have enabled the miniaturization of components and increased the accessibility of satellites as they find new applications in the form of Cube Satellites. However, even as these advancements have brought satellites to new heights, their interconnectedness leaves them open to new cyber threats. Ransomware attacks are one of the most prominent and disruptive cyber threats to terrestrial systems, and while …


Characterization Of An Omega Type Bi-Anisotropic Material, Moriel Gindi Mar 2024

Characterization Of An Omega Type Bi-Anisotropic Material, Moriel Gindi

Theses and Dissertations

A theory is presented for the extraction of the complete set of material parameters for a bi-anisotropic sample consisting of conductive omega-type particles governed by the mm21′ point-group symmetry. A rectangular-to-square wave-guide can be used to obtain the required measurements by allowing three distinct orientations of the material. The focus of this work is to develop the appropriate theory detailing the derivation of how the material parameters are extracted from the measurements in an analytical methodology that is similar in manner to the well-known Nicolson-Ross-Weir (NRW) algorithm.


Measuring The Presentation Of Supporting Content For A Set Of Learning Objectives Throughout The States Of An Educational Game Tree, Michael L. Hastriter Jr. Mar 2024

Measuring The Presentation Of Supporting Content For A Set Of Learning Objectives Throughout The States Of An Educational Game Tree, Michael L. Hastriter Jr.

Theses and Dissertations

In an era of evolving warfare, the Department of Defense (DoD) recognizes the value of serious games as immersive tools for teaching critical concepts. This thesis introduces a pioneering framework tailored to enhance learning objectives through the presentation of educational game content. This addresses the unique needs of the DoD and other educators who use games by providing measurements to assess educational games. This researches investigates how instructors might assess games as potential teaching tools. It establishes a five-phase process, providing a framework to assess educational games against predefined learning objectives and informing future game development. This thesis demonstrates games …


Design Considerations For The Use Of The Julia Programming Language In Future Quantum Networking Simulation Software, Takashi Joubert Mar 2024

Design Considerations For The Use Of The Julia Programming Language In Future Quantum Networking Simulation Software, Takashi Joubert

Theses and Dissertations

Given the prevalence of Python-based packages in the existing quantum network simulation ecosystem, we attempt to assess what might be realistically gained by switching to Julia. We focus our experimental activities on three areas: 1) surveying the characteristics of Julia as they tie into robust framework development, 2) presenting benchmarks that compare Julia and Python with respect to elements of possible simulation workloads, and 3) producing a tangible lightweight Julia architecture for modeling components in a manner similar to SeQUeNCe. Our analysis suggests that while Julia does o.er performance advantages over Python over certain workloads, knowing the reasons for why …


Malware Detection And Signature Propagation: A Study On Anti-Virus Platforms, Aaron J. Morath Mar 2024

Malware Detection And Signature Propagation: A Study On Anti-Virus Platforms, Aaron J. Morath

Theses and Dissertations

The early detection of malware across DoD networks is paramount when considering which AV engine to employ. This study explores malware detection latency across various AV providers over a 30-day period using VirusTotal’s platform. The analysis reveals an initial surge in detections, reaching approximately 60% within 24 hours. From days 3 to 20, detections steadily increase by 1-3 instances per day, peaking at 74% on the 20th day, followed by a slight decline. The research also highlights a significant difference in false positive rates between packed and non-packed non-malicious samples, emphasizing the impact of packing on AV engine scans. While …


Enhancing Sequence With Quantum Key Distribution Protocols And An Intuitive User Interface, Blake Perkins Mar 2024

Enhancing Sequence With Quantum Key Distribution Protocols And An Intuitive User Interface, Blake Perkins

Theses and Dissertations

The rapidly growing domain of quantum networks necessitates advancements in associated software packages. This master’s thesis will detail, in part, new protocols added to extend the usefulness of SeQUeNCe. Notably, these added protocols were implemented to ensure compatibility and efficiency with the existing codebase. To complement this expansion in capability, the graphical user interface (GUI) was restructured. Updates to the GUI now allow users to initiate and operate these newly integrated protocols with ease, thereby expanding the accessibility of SeQUeNCe to a wider audience. By prioritizing the incorporation of these new protocols and refining the user interface, this research significantly …


Opportunities And Limitations: Integrating Narrative Ai Into Game-Based Assessment Creation And Evaluating Student Impacts, Kevin B. Patterson Mar 2024

Opportunities And Limitations: Integrating Narrative Ai Into Game-Based Assessment Creation And Evaluating Student Impacts, Kevin B. Patterson

Theses and Dissertations

The Department of Defense (DoD) has identified the need for a technically proficient workforce in the areas of science, technology, engineering, and mathematics. To meet this need, the DoD is actively seeking innovative technology capable of creating workforce development opportunities that are both accessible and effective. Educational research indicates serious games provide a potential avenue to achieve this goal. Unfortunately, a limited number of tools that simplify the game development process and leverage artificial intelligence are available. Content-generating artificial intelligence might help reduce instructor and game-based assessment designers' workloads while promoting individualized learning in students. This research presents a novel …


Optimization Of Bluetooth Auracast Broadcast Audio Transmissions Via Signal Modeling, Lauren J. Puseman Mar 2024

Optimization Of Bluetooth Auracast Broadcast Audio Transmissions Via Signal Modeling, Lauren J. Puseman

Theses and Dissertations

Since 1994, Bluetooth has been used as a Personal Area Network (PAN) to transfer data between devices within a short range. After thirty years of progressive improvement in functionality, security, range, and power efficiency, the Bluetooth Special Interest Group has released a new feature called Auracast, which allows users to tune into nearby public audio streams and receive the feed directly to their wireless headphones or hearing aids. Soon, venues such as convention centers, museums, public forums, and sporting arenas can implement Auracast to better suit their needs. In addition to these public benefits, the Department of Defense can take …


A Machine Learning Approach For Multipath Characterization And Mitigation Using Chipshape Observations, Sean A. L. Quiterio Mar 2024

A Machine Learning Approach For Multipath Characterization And Mitigation Using Chipshape Observations, Sean A. L. Quiterio

Theses and Dissertations

Multipath continues to be a significant error source in satellite navigation. Recent solutions with Neural Networks (NN) model the effects of multipath on the autocorrelation function to predict errors in the Delay Lock Loop (DLL). Chipshape correlation provides a detailed look into the spreading code transitions in the time domain. It is useful in applications such as Signal Quality Monitoring (SQM) and is much more sensitive to multipath than autocorrelation. This research proposes NN models that each predict pseudorange or carrier range errors due to multipath by monitoring the chipshape correlation output. For a simulation with 50 MHz precorrelation bandwidth …


Performance Analysis Of Intel Total Memory Encryption - Multi-Key, Charles W. Rockett Mar 2024

Performance Analysis Of Intel Total Memory Encryption - Multi-Key, Charles W. Rockett

Theses and Dissertations

Secure cloud computing is an evolution in data management and security. As cloud-based services, ranging from storage solutions accessible from mobile devices to complex applications, become integral to daily operations, securing data throughout the life cycle of its use is essential. In response, hardware companies are advancing encryption and security technologies to protect data in use to thwart unauthorized access while mitigating the performance impacts of security and encryption features. This thesis addresses TME-MK performance when enabled and disabled on a server using all host threads and with three virtualized environments assigned separate unique threads each. The primary aim is …


Reconstruction Of Radar Range Profiles Using Dropped Channel Polarimetric Compressive Sensing, Nat Thomason Mar 2024

Reconstruction Of Radar Range Profiles Using Dropped Channel Polarimetric Compressive Sensing, Nat Thomason

Theses and Dissertations

This thesis documents the design, construction and testing of a bench-top level measurement system and verifies previously established Dropped Channel Polarimetric Synthetic Aperture Radar Compressive Sensing (DCPCS) simulation results. Compressive Sensing is a mathematical technique which can capture and represent compressible signals at sampling rates significantly below the Nyquist rate. DCPCS is a technique which enhances Compressive Sensing techniques using known physical antenna crosstalk values. The DCPCS technique enables reconstruction of fully polarimetric signals whilst only measuring part of the signal, reducing data capture requirements.