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Fluid Dynamics Modeling For Per- And Polyfluoroalkyl Substances Removal In Legacy Fire Suppression Systems, Jacob G. Spaulding
Fluid Dynamics Modeling For Per- And Polyfluoroalkyl Substances Removal In Legacy Fire Suppression Systems, Jacob G. Spaulding
Theses and Dissertations
Legacy per- and polyfluoroalkyl substances (PFASs) exist in the form of aqueous film-forming foams within hangar fire suppression systems throughout the country, posing a threat to both surrounding environments as well as local populations. The United States (US) Department of Defense (DoD), in conjunction with the US Environmental Protection Agency (EPA), is investigating best practices to flush out existing contaminants prior to disposal and replacement with a less environmentally harmful replacement. While current procedures dictate a triple rinse of the entire system to yield contaminant levels acceptable to the DoD, the practice has never truly been tested. Designed as a …
Analysis Of Time-Phased Estimates Accuracy, Budget Profile And Under-Spending In Defense Acquisition Programs, Thinh Q. Tran
Analysis Of Time-Phased Estimates Accuracy, Budget Profile And Under-Spending In Defense Acquisition Programs, Thinh Q. Tran
Theses and Dissertations
As fiscal resources become more limited due to the expanding range of mission needs, accurate cost estimating and budgeting have become more important than ever before. Accurate cost estimates allow the Department of Defense (DoD) to budget with confidence and to effectively communicate its needs to Congress. This research looks to analyze estimates from Air Force’s programs using Milestone B and Initial Operational Capability as the analysis window. Initial analysis of the linear interpolation of the percent budget change indicates that there is underspending in the earlier stages of acquisition programs’ development cycle. Additionally, looking at the cumulative budget change …
Climate-Informed Prediction And Forecast Modeling Of Installation Total Energy Consumption, Scott C. Weiss
Climate-Informed Prediction And Forecast Modeling Of Installation Total Energy Consumption, Scott C. Weiss
Theses and Dissertations
Climate variability is an external and stochastic factor that causes energy demand uncertainty. Energy managers can use climate-based models to understand future trends of energy demand and to adjust operations, policy, and budgets accordingly. This research focuses on 1) identifying how climate attributes impact energy use, 2) creating a historically informed statistical modeling framework to skillfully predict energy use, and 3) forecasting future changes to energy use and costs, using CMIP5 temperature projections, at the campus level. After synthesizing the existing breadth of research on climate-informed energy modeling, a skillful, unbiased, climate-informed total energy consumption prediction model is developed for …
Error Detection In Quantum Algorithms, Simeon R. Hanks
Error Detection In Quantum Algorithms, Simeon R. Hanks
Theses and Dissertations
Quantum computers need to be able to control highly entangled quantum states in the presence of environmental perturbations that lead to errors in calculations. Progress in superconducting qubits has enabled the development of computers capable of running small quantum circuits. The current era of Noise Intermediate Scale Quantum computing has a high error rate. To alleviate this error rate we apply an encoding scheme that allows us to remove results with known errors improving the quality of our results. The encoding uses multiple qubits as a single logical qubit and balances the natural tendency of state-of-the-art quantum computers to decohere …
Ab Initio Spectroscopy Of Natural And Artificial Fire Contaminants For V/W Band Frequency Signal Absorbance, Matthew B. Husk
Ab Initio Spectroscopy Of Natural And Artificial Fire Contaminants For V/W Band Frequency Signal Absorbance, Matthew B. Husk
Theses and Dissertations
The rotation and vibration spectral properties including frequencies and intensities for highly concentrated molecules present in wildland and artificial fires have been studied. These properties were used to determine absorption and its effect in a link budget analysis. Absorption in link budget analyses is commonly accounted for via line-by-line methodology aided by HITRAN documented intensities. Limited, if any, customization of spectral properties is available with HITRAN and other spectral databases. Ab initio calculations with different atomic basis sets were employed to obtain structures, dipole moments, rotational-vibrational frequencies and intensities, as well as various coupling parameters. Anharmonic corrections to the vibrational …
Examination Of A Lenseless Setup For Reflective Inverse Diffusion Of Light, John Nguyen
Examination Of A Lenseless Setup For Reflective Inverse Diffusion Of Light, John Nguyen
Theses and Dissertations
Reflective inverse diffusion uses spatial light modulators to shape an incident wavefront so that when the wavefront interacts with some diffuse scattering sample, the reflected light will constructively interfere at a single focus. This thesisexamines the efficacy of using a lensless setup against a focal plane setup in achieving reflective inverse diffusion while simultaneously beamsteering. The lensless setup outperformed its counterpart by being able to focus more energy in a region, but failed to achieve the same beamsteering capabilities as the focal plane system. Understanding the flaws behind the lensless setup will be instrumental in creating a setup that can …
Synthetic Lightning Generation Employing Autoregressive-Moving-Average (Arma) Models, Seth R. Powers
Synthetic Lightning Generation Employing Autoregressive-Moving-Average (Arma) Models, Seth R. Powers
Theses and Dissertations
This work explores the question as to whether lightning data can be generated synthetically using vector autoregressive-moving-average (VARMA) models. Geostationary Lightning Mapper (GLM) data is used as the basis for the study. Lightning climatology is examined and compared to previous research to gain insight into the targeted areas. Individual lightning ashes are analyzed to inspect how well the process works on a smaller scale. Then, entire regions are evaluated to simulate lightning creation in a larger setting. Results suggest that the VARMA process employed is sufficient in generating synthetic lightning observations, largely dependent on the time and location of lightning …
Aircraft Inspection By Multirotor Uav Using Coverage Path Planning, Patrick H. Silberberg
Aircraft Inspection By Multirotor Uav Using Coverage Path Planning, Patrick H. Silberberg
Theses and Dissertations
All military and commercial aircraft must undergo frequent visual inspections in order to identify damage that could pose a danger to safety of flight. Currently, these inspections are primarily conducted by maintenance personnel. Inspectors must scrutinize the aircraft’s surface to find and document defects such as dents, hail damage, broken fasteners, etc.; this is a time consuming, tedious, and hazardous process. The goal of this work is to develop a visual inspection system which can be used by an Unmanned Aerial Vehicle (UAV), and to test the feasibility of this system on military aircraft. Using an autonomous system in place …
Dynamic Holography In Resonant Nonlinear Media: Theory And Application, Jonathan E. Slagle
Dynamic Holography In Resonant Nonlinear Media: Theory And Application, Jonathan E. Slagle
Theses and Dissertations
Two beam coupling (TBC) is a coherent interaction in which energy is transferred from one laser beam to another and has promising applications in real-time holography and coherent beam combing. We have recently shown efficient degenerate frequency TBC for counter-propagation geometries in isotropic two-photon absorbing media pumped with a nanosecond pulsed laser. When an interference pattern is generated in this media, single and two photon absorption initiates a population redistribution resulting in a holographic grating with the same modulation period and phase initially. However, due to temporal convolution of self- and cross-phase modulation, the grating will begin to shift in …
Space To High-Altitude Region Adjoint Neutron Transport, Zachary W. Lamere
Space To High-Altitude Region Adjoint Neutron Transport, Zachary W. Lamere
Theses and Dissertations
The goal of this work was to use the adjoint transport equation to characterize the energy spectrum of a point neutron source using the time-energy fluence at the satellite. The adjoint transport was solved via Monte Carlo methods in the new program called Space to Air High-Altitude Region Adjoint (SAHARA). A new adjoint source event estimator was developed to improve the computational efficiency. This work explores SAHARA’s performance using mono-energetic and continuous sources. In general, the identified source spectra were noticeably shifted towards lower energies, but were able to capture the source spectrum shapes. Lastly, SAHARA was applied to the …
Characterization And Analysis Of Bomarc Accident Debris, Aaron J. Heffelfinger
Characterization And Analysis Of Bomarc Accident Debris, Aaron J. Heffelfinger
Theses and Dissertations
Accidents involving nuclear weapons, such as the Boeing Michigan Aeronautical Research Center (BOMARC) accident in 1960, always pose a significant risk of allowing particles composed of nuclear materials to enter the environment. These particles often differ in characteristics and can be of greatly varying sizes. Gamma ray analysis was conducted on the soil sample and radioisotopes within the sample were identified. Two non-destructive methods for locating actinide bearing particles within the sample were testing, resulting in 70 actinide bearing particles ranging from 1-34 microns being identified. These 70 particles underwent both morphological and elemental characterization, indicating uranium and other elements.
Characterization Of The Spatial Distribution And Evolution Of Cerium And Calcium In Laser Produced Plasma, Michael G. Rynders
Characterization Of The Spatial Distribution And Evolution Of Cerium And Calcium In Laser Produced Plasma, Michael G. Rynders
Theses and Dissertations
Understanding plasma plumes and the distribution of plasma species microseconds after their formation has a variety of applications in fields such as hypersonics, explosion and combustion dynamics, and nuclear fireball chemistry. In this work, Laser Induced Breakdown Spectroscopy (LIBS) using double pulses of 532 nm light were used to analyze samples of cerium in atmospheres of air, vacuum, and argon. Cerium was used in this experiment to serve as a plutonium surrogate. CeO2 powder was pressed with CaO at 90-10 ratio to produce calcium doped pellets for use as sputtering targets. Inclusion of calcium impurities allowed the identification of …
Topological Realizations Of Entangling Quantum Gates, Adrian D. Scheppe
Topological Realizations Of Entangling Quantum Gates, Adrian D. Scheppe
Theses and Dissertations
Topological systems are immune to decoherence and provide a hunting ground for qubits that are fault tolerant. The process of calculating linear operator representations of Majorana fermion exchanges or braids is well known and well documented; however, there is no documented intuition or algorithm which provides the opposite; braids from quantum gates. In this document, all possible linear representations of single, double, triple, and quadruple qubit gates are calculated to find several key patterns which provide crucial insight into the manifestation of qubit gates. A n x n gate will require n + 2 Majoranas with ½n + 1 trivial …
Application Of Artificial Neural Networks To Elemental Assay Data For Nuclear Forensics Analysis, Jason G. Seik
Application Of Artificial Neural Networks To Elemental Assay Data For Nuclear Forensics Analysis, Jason G. Seik
Theses and Dissertations
There is a need to quickly and accurately determine the likely physical origins of a collected sample for nuclear treaty verification purposes. The objective of this research is to prove there is a means to relate different samples (Q-values) to one another using a 'same versus not-same' artificial neural network called a Siamese network. This would provide the capability of comparing an unknown sample to a database of samples with known physical origins. Using moment transformations on current data has shown to increase the prediction capabilities of a Siamese network, and using a triplet loss function in connection with the …
Lithium Compound Characterization Via Laser Induced Breakdown Spectroscopy And Raman Spectroscopy, James T. Stofel
Lithium Compound Characterization Via Laser Induced Breakdown Spectroscopy And Raman Spectroscopy, James T. Stofel
Theses and Dissertations
Industries such as lithium-ion battery producers and the nuclear industry community seek to produce and store lithium in pure chemical forms. However, these lithium compounds are reactive with the atmosphere and quickly degrade into less desirable forms. Therefore, industry desires a fast and effective quality control approach to quantify the ingrowth of these secondary lithium chemical forms. This research presents a novel approach using Laser-Induced Breakdown Spectroscopy (LIBS) and Raman spectroscopy in tandem to enhance lithium compound characterization beyond what is achieved by either technique alone. The resulting spectral data are aggregated using data fusion and analyzed using chemometrics for …
Data Driven Investigation Into The Off-Axis Brdf To Develop An Algorithm To Classify Anisotropicity, Anne W. Werkley
Data Driven Investigation Into The Off-Axis Brdf To Develop An Algorithm To Classify Anisotropicity, Anne W. Werkley
Theses and Dissertations
The Bi-directional Reflectance Distribution Function (BRDF) is used to describe reflectances of materials by calculating the ratio of the reflected radiance to the incident irradiance. While it was found that isotropic BRDF microfacet models maintained symmetry about ɸs = π, such symmetry was not maintained about the θs = θi axis, except for close to the specular peak. This led to development of a novel data-driven metric for how isotropic a BRDF measurement is. Research efforts centered around developing an algorithm that could determine material anisotropy without having to fit to models. The algorithm developed here successfully …
Contract Information Extraction Using Machine Learning, Zachary E. Butcher
Contract Information Extraction Using Machine Learning, Zachary E. Butcher
Theses and Dissertations
The Air Force Sustainment Center assisted by the Data Analytics Resource Team and the Defense Logistics Agency collected four million contracts onto one of the Air Force Research Laboratory’s high power computers. This thesis focuses on the effort to determine if parts are available through those contracts. Some information is extracted using machine learning in combination with natural language processing. Where machine learning methods are unsuccessful or inappropriate, text mining techniques, such as pattern recognition and rules, are used. Upon completion, the information is combined into a Gantt chart for quick evaluation. Only 21% of the contracts have their information …
The Obstacles To The Modernization Of Common Support Equipment, J. Erik Ritschard
The Obstacles To The Modernization Of Common Support Equipment, J. Erik Ritschard
Theses and Dissertations
The current fleet of Common Support Equipment (CSE) is faced with a $2B funding disconnect that threatens 9 of the 12 USAF Core Functions. This research identifies the barriers to efforts to modernize CSE across the sustainment, acquisition, and maintenance communities. Using a qualitative, grounded theory methodology, the responses are explored of interviewed Support Equipment managers responsible for the sustainment and modernization of CSE. Significant barriers to current modernization efforts were exposed, resulting in expensive, duplicative, and unreliable equipment; concluding that the AF must change the way CSE is administrated, funded, and culturally understood to prevent future mission degradation.
Defensive Counterair For Air Base Air Defense Using Directed Energy And Kinetic Energy Weapons, Andrew S. Wilson
Defensive Counterair For Air Base Air Defense Using Directed Energy And Kinetic Energy Weapons, Andrew S. Wilson
Theses and Dissertations
Air bases in key locations provide a strategic advantage to the countries that access them, and are at constant threat from adversaries. This research seeks to determine the optimal maneuvering of a fixed number of fighter aircraft in a combat air patrol for defensive counterair to maximally and effectively attrit the inbound cruise missile threat to a stationary high value asset such as an air base. The problem formulation identifies multiple objectives for the model: minimize the distance traveled for the fighters, minimize the time utilized to engage the incoming cruise missiles, and maximize the number of cruise missiles destroyed. …
Developing Infrastructure Adaptation Pathways To Combat Hurricane Intensification: A Coupled Storm Simulation And Economic Modeling Framework For Coastal Installations, Alexander J. Baldwin
Developing Infrastructure Adaptation Pathways To Combat Hurricane Intensification: A Coupled Storm Simulation And Economic Modeling Framework For Coastal Installations, Alexander J. Baldwin
Theses and Dissertations
Climate change projections suggest intensification of extreme weather events, including hurricanes, is expected throughout the 21st century. This will lead to increased destruction for coastal military bases unless infrastructure resiliency and adaptation measures are implemented. This research focuses on examining the simulation of probabilistic, climate-intensified hurricane events at Eglin Air Force Base. FEMA Hazus models are combined with climate projections for wind Intensity, tide, and sea-level rise to produce an assessment of losses to the installation. Damage estimates and hurricane intensity outputs are downscaled to the facility-level so that climate adaptation signals can be identified. The facility losses and climate …
An Analysis Of The Effects Of Technology Readiness Levels On Cost Growth, Christopher R. Bissing
An Analysis Of The Effects Of Technology Readiness Levels On Cost Growth, Christopher R. Bissing
Theses and Dissertations
This research seeks to evaluate the effects of Technology Readiness Levels (TRL) on Cost Growth. It makes use of data from Technology Readiness Assessments (TRA) and Selected Acquisition Reports (SAR) to explore relationships between TRLs at Milestone B and cost growth in Major Defense Acquisition Programs (MDAP) and Major Automated Information Systems (MAIS). Programs using higher proportions of critical technologies rated below TRL 7 tend to experience greater cost growth than programs that use more mature technologies. Current DoD doctrine requires TRL 6 to enter Milestone B. The results of this research seek to evaluate the merit of this requirement. …
Display Design To Avoid And Mitigate Limit Cycle Oscillations (Lco) On The F-16c, David J. Feibus
Display Design To Avoid And Mitigate Limit Cycle Oscillations (Lco) On The F-16c, David J. Feibus
Theses and Dissertations
The U.S. Air Force F-16 Fighting Falcons flying characteristics and flight envelope are dynamic and defined by its external weapon stores configuration. The employment of its munitions at certain speeds can put the F-16 into a flutter-like state in which Limit Cycle Oscillations (LCO) are induced. In LCO, a pilots fine motor control might be hindered, and the aircraft may lose combat effectiveness until flight conditions are reduced. The current research attempted to provide pilots with a predictive feedback display to avoid an LCO-susceptible configuration by increasing their situation awareness about the consequences of employing certain munitions to their flight …
Optimizing Critical Values And Combining Axes For Multi-Axial Neck Injury Criteria, Ethan J. Gaston
Optimizing Critical Values And Combining Axes For Multi-Axial Neck Injury Criteria, Ethan J. Gaston
Theses and Dissertations
The Air Force employs ejection seats in its high-performance aircraft. While these systems are intended to ensure aircrew safety, the ejection process subjects the aircrew to potentially injurious forces. System validation includes evaluation of forces against a standard which is linked to the probability of injury. The Muti-Axial Neck Injury Criteria (MANIC) was developed to account for forces in all six degrees of freedom. Unfortunately, the MANIC is applied to each of the three linear input directions separately and applies different criterion values for each direction. These three separate criteria create a lack of clarity regarding acceptable neck loading, leading …
Long Distance Bluetooth Low Energy Exploitation On A Wireless Attack Platform, Stephanie L. Long
Long Distance Bluetooth Low Energy Exploitation On A Wireless Attack Platform, Stephanie L. Long
Theses and Dissertations
In the past decade, embedded technology, known as the Internet of Things, has expanded for many uses. The smart home infrastructure has drastically grown to include networked refrigerators, lighting systems, speakers, watches, and more. This increase in the use of wireless protocols provides a larger attack surface for cyber actors than ever before. Wireless loT traffic is susceptible for sniffing by an attacker. The attack platform skypie is upgraded to incorporate Bluetooth Low Energy (BLE) beacon collection for pattern-of-life data, as well as device characteristic enumeration and potential characteristic modification. This platform allows an attacker to mount the skypie to …
Error Reduction For The Determination Of Transverse Moduli Of Single-Strand Carbon Fibers Via Atomic Force Microscopy, Joshua D. Frey
Error Reduction For The Determination Of Transverse Moduli Of Single-Strand Carbon Fibers Via Atomic Force Microscopy, Joshua D. Frey
Theses and Dissertations
The transverse modulus of single strand carbon fibers is measured using PeakForce Atomic Force Microscopy - Quantitative Nanomechanical Measurement to less than 5 percent error for 11 types of carbon fiber with longitudinal moduli between 924-231 GPA, including export-controlled fibers. Statistical methods are employed to improve the quality of data to exclude outliers within an measurement and within the sample set. A positive linear correlation between the longitudinal and transverse modulus with an R2=0.76 is found. Pitch-based fibers exhibit lower measurement error than PAN-based fibers, while PAN fibers exhibited no apparent modulus correlation when the Pitch fibers are …
Correction Of Back Trajectories Utilizing Machine Learning, Britta F. Gjermo Morrison
Correction Of Back Trajectories Utilizing Machine Learning, Britta F. Gjermo Morrison
Theses and Dissertations
The goal of this work was to analyze 24-hour back trajectory performance from a global, low-resolution weather model compared to a high-resolution limited area weather model in particular meteorological regimes, or flow patterns using K-means clustering, an unsupervised machine learning technique. The duration of this study was from 2015-2019 for the contiguous United States (CONUS). Three different machine learning algorithms were tested to study the utility of these methods improving the performance of the CFS relative to the performance of the RAP. The aforementioned machine learning techniques are linear regression, Bayesian ridge regression, and random forest regression. These results mean …
Guidance For Building Motivation In Space Operator Training, Foster E. Davis
Guidance For Building Motivation In Space Operator Training, Foster E. Davis
Theses and Dissertations
Services provided by spacecraft, including communications and global positioning, are integral to small businesses, multinational corporations, and the United States Department of Defense. United States rivals recognize the need to undermine the military advantage provided by the space domain and are exploring ways to degrade these services in their warfare doctrine. In response, the United States will need space systems suited to counter these threats and personnel who are trained to respond to the new reality of a contested space environment. This paper also reviews the academic literature and written guidelines for developing motivation in an interactive environment for improving …
Modeling Situation Awareness In A Uav Scenario Using Sysml, Tommy R. Hernandez
Modeling Situation Awareness In A Uav Scenario Using Sysml, Tommy R. Hernandez
Theses and Dissertations
The U.S. Department of Defense (DoD) is rapidly moving towards using increasingly automated systems. Unmanned Aerial Systems (UAS) will be used in contested environments where direct human control may be impossible for long stretches of time. This increase in automation brings with it challenges in maintaining resilient Situation Awareness (SA) for operators, who still need to set goals for the UAS to accomplish their missions. Simultaneously, the DoD is increasing the adoption of Model-Based Systems Engineering (MBSE) in the development of weapon systems. This thesis explores the use of SysML to model of an SA repair system for a UAS …
An Empirical Analysis Of Dod Construction Task Order Performance, Adam B. Teston, Tyler S. Stout
An Empirical Analysis Of Dod Construction Task Order Performance, Adam B. Teston, Tyler S. Stout
Theses and Dissertations
Cost and schedule overrun plague over 50 of all construction projects, engendering diminished available funding that leads to deferred maintenance and impaired award ability for needed projects. Though existing research attempts to identify overruns sources, the results are inconclusive and frequently differ. Accordingly, this research reviews DoD construction contract data from the past ten years to identify the contract attributes of 79,894 projects that correlate with superior performance for use in future project execution. This research starts with creating a database that houses the largest single source of construction contract information. The research then evaluates the data to determine if …
The Wargaming Commodity Course Of Action Automated Analysis Method, William T. Deberry
The Wargaming Commodity Course Of Action Automated Analysis Method, William T. Deberry
Theses and Dissertations
This research presents the Wargaming Commodity Course of Action Automated Analysis Method (WCCAAM), a novel approach to assist wargame commanders in developing and analyzing courses of action (COAs) through semi-automation of the Military Decision Making Process (MDMP). MDMP is a seven-step iterative method that commanders and mission partners follow to build an operational course of action to achieve strategic objectives. MDMP requires time, resources, and coordination – all competing items the commander weighs to make the optimal decision. WCCAAM receives the MDMP's Mission Analysis phase as input, converts the wargame into a directed graph, processes a multi-commodity flow algorithm on …