Engineering Commons^™

Meeting The Dod’S Tactical Weather Needs Using Cubesats, Shayna K. Mckenney

Theses and Dissertations

This thesis investigates a CubeSat design that uses Commercial-Off-The-Shelf (COTS) components to capture, store, process, and downlink collected terrestrial weather data at resolutions near stat-of-the-art. The weather phenomena to be detected and transmitted in a timely manner are cloud formations, wind profiles, ocean currents, sea state, lightning, temperature profiles, and precipitation. It is hypothesized and shown that the proposed design will provide an improvement on the current U.S. tactical weather collection satellites because of the anticipated increased reliability and lowered cost to build and maintain the proposed CubeSat constellation. The methodology employed a multi-phase approach through the collective research of …

Design And Experimentation Of A Premixed Rotating Detonation Engine, Ionio Q. Andrus

Theses and Dissertations

Desire for a more efficient air breathing engine has shifted research attention to the Rotating Detonation Engine (RDE). Detonation is a more efficient combustion process than deflagration and provides a pressure gain. The RDE detonation cycle occurs in a compact volume to produce a high specific impulse engine. Computational fluid dynamic (CFD) models have predicted higher specific impulse and detonation wave speeds than has been seen in experimental RDE. The CFD models frequently assume premixed reactants and ignore inlet geometries to facilitate rapid computation. An experimental premixed RDE was sought to test if the premixed assumption in CFD was the …

An Investigation In Construction Cost Estimation Using A Monte Carlo Simulation, Jeffrey D. Buchholtz

Theses and Dissertations

The Air Force estimates military construction (MILCON) costs early in a project’s development as a part of the funding approval process. However, many of the initial cost estimates deviate significantly more than expected from the actual project costs, hindering funding allocation efforts. There is a need for improved estimation techniques. This research examines a cost estimation model for the initial programming stages of a project when only general scope information is available.

This study develops a Monte Carlo simulation based on historical construction cost data to predict project costs base on facility type. For a given facility type, the research …

Using Approximate Dynamic Programming To Solve The Stochastic Demand Military Inventory Routing Problem With Direct Delivery, Ethan L. Salgado

Theses and Dissertations

A brigade combat team must resupply forward operating bases (FOBs) within its area of operations from a central location, mainly via ground convoy operations, in a way that closely resembles vendor managed inventory practices. Military logisticians routinely decide when and how much inventory to distribute to each FOB. Technology currently exists that makes utilizing cargo unmanned aerial vehicles (CUAVs) for resupply an attractive alternative due to the dangers of utilizing convoy operations. However, enemy actions, austere conditions, and inclement weather pose a significant risk to a CUAV's ability to safely deliver supplies to a FOB. We develop a Markov decision …

Investigation Of Thermal Scaling Effects For A Turbine Blade Leading Edge And Pressure Side Model, Ryan A. Lynch

Theses and Dissertations

Recent experiments have attempted to quantify the overall cooling effectiveness at elevated temperature conditions. The Film Cooling Rig (FCR) at the Air Force Institute of Technology has been modified to better match the configuration of a similar large scale, low temperature rig at the Air Force Research Laboratory. This has enabled comparison and trend identification of how various properties scale from the low to high temperature condition. Various internal cooling and hole geometry configurations were investigated over a range of temperatures while utilizing the thermal scaling capability of Inconel 718. Film cooling trends and measures of overall effectiveness were matched, …

Air Mobility Future: Evolving Command And Control Relationships In The Information Age, Ian M. Slazinik

Theses and Dissertations

This research paper analyzes information flow through theater Air Mobility Command and Control (C2) organizations. The purpose is to uncover guidelines going forward to adapt organizational structure and processes to increase the speed and reach of information. These guidelines could assist with improving organizational agility and decision making while adapting to future trends in the broader C2 enterprise. To collect data, the researcher conducted interviews with seventeen C2 experts with experience at various levels of C2, from worldwide to theater Air Mobility C2 organizations, from Air Mobility C2 leadership, to experts in non-mobility C2 divisions. Interview subjects shared their perceptions …

Heterogeneous Air Defense Battery Location: A Game Theoretic Approach, Nicholas T. Boardman

Theses and Dissertations

The Unites States and its allies confront a persistent and evolving threat from missile attacks as nations around the world continue to invest and advance their current capabilities. Within the air defense context of a missile-and-interceptor engagement, a challenge for the defender is that surface to air interceptor missile batteries often must be located to protect high-value targets dispersed over a vast area, subject to an attacker observing the disposition of batteries prior to developing and implementing an attack plan. To model this scenario, we formulate a two-player, three-stage, perfect information, sequential move, zero-sum game that accounts for, respectively, a …

Radiation Effects On An Active Ytterbium-Doped Fiber Laser, Adam C. Poulin

Theses and Dissertations

This is the first published research focused on the impact of gamma and mixed gamma/neutron radiation on an actively lasing ytterbium-doped fiber laser. While the gain medium of the ytterbium-doped fiber laser was irradiated, the power was measured in-situ and the spectrum was recorded intermittently. Two radiation sources were used, a ⁶⁰Co cell and a reactor. Three irradiation experiments were conducted per radiation source; pristine fibers were used for the first two experiments, and fibers from the second experiment were re-irradiated for the third experiment. The results indicate that as the total dose increased linearly with time, the laser …

Evaluation Of The Visible Infrared Imaging Radiometer Suite (Viirs) Cloud Base Height (Cbh) Pixel-Level Retrieval Algorithm For Single-Layer Water Clouds, Kyle E. Fitch

Theses and Dissertations

Evaluation of the Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Base Height (CBH) product was accomplished. CBH is an important factor for aviation, but a lack of coverage for ground-based retrieval is a significant limitation. Space-based retrieval is essential; therefore, the VIIRS CBH pixel-level retrieval algorithm was assessed for single-layer water clouds. Accurate (truth) measurements were needed not only for the CBH product, but also for VIIRS cloud optical thickness (COT), effective particle size (EPS), and cloud top height (CTH). Data from Atmospheric Radiation Measurement (ARM) sites were used, with VIIRS-ARM matchups created from June 2013 through October 2015 for …

Creep Of Hi-Nicalon™ S Ceramic Fiber Tows At 700°C In Air And In Silicic Acid-Saturated Steam, Matthew W. Piper

Theses and Dissertations

Aircraft structural and engine components are subjected to elevated temperature and steam environments during operation. Turbine blades experience particularly harsh conditions that are approaching the operating temperature limits of current Nickel-based superalloys even with active cooling. Ceramic matrix composites (CMCs), which demonstrate high specific strength and specific stiffness and maintain these properties at elevated temperatures such that active cooling is not required, are prime candidates to replace superalloys as the materials for turbine blades. Ceramic matrix composites are composite materials that consist of a ceramic matrix with fiber reinforcement. This research investigated a silicon carbide (SiC) fiber, Hi-Nicalon™ S, which …

Hardware Development And Error Characterisation For The Afit Rail Sar System, Dayne A. Schmidt

Theses and Dissertations

This research is focussed on updating the Air Force Institute of Technology (AFIT) Radar Instrumentation Lab (RAIL) Synthetic Aperture Radar (SAR) experimental system. Firstly, this research assesses current hardware limitations and updates the system configuration and methodology to enable collections from a receiver in motion. Secondly, orthogonal frequency-division multiplexing (OFDM) signals are used to form (SAR) images in multiple experimental and simulation configurations. This research analyses, characterises and attempts compensation of relevant SAR image error sources, such as Doppler shift or motion measurement errors (MMEs). Error characterisation is conducted using theoretical, simulated and experimental methods. Final experimental results are presented …

Contingency Workload Demand Forecast Techniques For Cargo And Flying Hours, Calvin J. Bradshaw Iii

Theses and Dissertations

Accurate forecasting of contingency workload demand for USTRANSCOM (USTC) is a herculean effort. Transportation Working Capital Fund (TWCF) managers rely on various subject matters outside and within the combatant command to estimate future workload. Since rates are set annually, when TWCF activities use incorrect or incomplete projections of workload, this leads to erroneous price structures and misaligned customer billing rates. The USTC leadership lacks the ability to accurately forecast workload demand, which is a key driver for service provider rate-setting. As a result, some customers perceive spiked rates and seek service from other competitors, which generates lost revenue, customer dissatisfaction …

Determination Of Fire Control Policies Via Approximate Dynamic Programming, Michael T. Davis

Theses and Dissertations

Given the ubiquitous nature of both offensive and defensive missile systems, the catastrophe-causing potential they represent, and the limited resources available to countries for missile defense, optimizing the defensive response to a missile attack is a necessary endeavor. For a single salvo of offensive missiles launched at a set of targets, a missile defense system protecting those targets must decide how many interceptors to fire at each incoming missile. Since such missile engagements often involve the firing of more than one attack salvo, we develop a Markov decision process (MDP) model to examine the optimal fire control policy for the …

The Impact Of Reducing Full Time Support Positions In The U.S. Army National Guard And Reserves, Lucas J. Lease

Theses and Dissertations

The United States Army is at a point in its history in which it, along with the other branches of the military, are experiencing cuts, constraints and a tightening of resources. The days of seemingly large budgets, abundant financial resources and high amounts of manpower are becoming a thing of the past. As the government reduces the allocations to the military, it is examining ways to reduce costs and improve its financial prospects. One of the positions examined for reduction or outright elimination is the full time support position in the U.S. Army National Guard (ARNG) and Reserves (USAR). The …

Methods To Address Extreme Class Imbalance In Machine Learning Based Network Intrusion Detection Systems, Russell W. Walter

Theses and Dissertations

Despite the considerable academic interest in using machine learning methods to detect cyber attacks and malicious network traffic, there is little evidence that modern organizations employ such systems. Due to the targeted nature of attacks and cybercriminals’ constantly changing behavior, valid observations of attack traffic suitable for training a classifier are extremely rare. Rare positive cases combined with the fact that the overwhelming majority of network traffic is benign create an extreme class imbalance problem. Using publically available datasets, this research examines the class imbalance problem by using small samples of the attack observations to create multiple training sets that …

An Economic Analysis Of The Transition Of A Contingency Military Installation To An Enduring Status Using Monte Carlo Simulations, Ryan M. Amedee

Theses and Dissertations

The construction of expeditionary bases is central to Department of Defense’s (DoD) responses to contingency operations. Usually expected to be transitory, expeditionary bases are constructed with temporary materials that can be erected quickly. The Global War on Terrorism is entering its fifteenth year and bases within Central Command that were expected to be temporary have provided an enduring presence. The decision to transition a base from temporary to semi-permanent or permanent is difficult, as it requires substantial capital investment for facility construction. This decision is further complicated by unknown mission durations. The DoD has attempted to reduce the decision’s complexity …

The Effect Of Ph And Pulsed Ultraviolet Light Emitting Diode Duty Cycles On The First Order Rate Constant And Byproduct Profile Of The Advanced Oxidation Of Tartrazine, Brandon M. Stewart

Theses and Dissertations

Water treatment capability is required for military operations, production of drinking water, and industrial wastewater treatment. The Advanced Oxidation Process (AOP) is one of many viable steps for treating water; however, it is important to understand the byproducts of the treatment process to avoid creating other constituents more severe than the first. Tartrazine (TAR) was oxidized with pulsed Ultra- Violet (UV) Light Emitting Diodes (LEDs) in combination with hydrogen peroxide (H2O2) in an AOP at the laboratory scale. The relative concentration of TAR was reduced from 1 to between 1 – 0.75 over pH values between 6 and 9, and …

A Simulation-Based Analysis Of Chemical And Radiological Hazard Zones Adapted To Physical Boundaries, Mickie J. Sundheim

Theses and Dissertations

In the United States, industrial and terrorist use of chemical, biological, radiological, and nuclear (CBRN) materials pose a risk to public safety. During the initial phase of typical CBRN incidents, emergency responders establish hazard zones based on standard distances from published guidelines and recommendations. This research investigates how standard hazard zones change in a real world environment that accounts for physical boundaries. Using a python simulation in ArcGIS®, new hazard zones were created by expanding standard hazard zones to follow nearby roads, railroads, and rivers. The new and standard zones were compared by calculating the population and area affected by …

Military Applications Of High-Altitude Satellite Orbits In A Multi-Body Dynamical Environment Using Numerical Methods And Dynamical Systems Theory, Meredith M. Wilmer

Theses and Dissertations

The circular restricted three-body problem (CR3BP) is a simplified dynamical model for a satellite under the gravitational influence of both the Earth and the Moon, maintaining closer fidelity to the gravitational environment experienced by a high-altitude Earth-orbiting spacecraft than modeling in the Earth-satellite two-body problem. Resonant orbit arcs are used to determine an initial guess to input into an algorithm that computes a trajectory solution with specific design requirements and constraints. A test case uses this method to compute a lunar fly-by transfer solution requiring less than two-body transfer methods and offers an unusual pathway that adds an unpredictability element …

Tunable Terahertz Metamaterials With Germanium Telluride Components, Christopher H. Kodama

Theses and Dissertations

Terahertz (THz) technology is an emerging field with many exciting applications. THz waves can be used to locate explosives and illicit drugs in security applications, or DNA and other molecule resonances in medical applications. THz frequencies represent the next level of modern, high-speed computing, but they also can be used for covert battlefield communications links. Metamaterials are an integral part of THz technology because they can be used to create exotic material properties—permittivities and permeabilities—in a part of the frequency spectrum that is otherwise rather empty and passive. This work aims to acquire a fuller understanding of THz metamaterials in …

Utilization Of A Geodesic Sphere And Quadcopter As Two-Way Field Probe For Electro-Magnetic Field Measurements In An Indoor Radar Cross Section Range, Nathan Lett

Theses and Dissertations

Radar Cross Section (RCS) measurements rely heavily on multiple assumptions. Uncertainty in the final measurement is determined based on these assumptions. One source in particular is the non-homogeneous nature of the transmission path between radar test equipment and a target under test. The following research extends prior research. This thesis intends to provide a unique two-way field probe solution for measuring Electro-magnetic (EM) fluctuations in a test volume. In this thesis, the design, development, and demonstration of a geodesic sphere encased quadcopter two-way probe is explained. The Parrot® Bebop Drone quadcopter was used with a 2v frequency divided geodesic sphere …

Characterization For The Development Of The Hybrid Multi-Junction Silicon Germanium Solar Cell, Jimmy J. Lohrman

Theses and Dissertations

Based on the previous development of the hybrid multi-junction silicon (HMJ-Si) solar cell, this work characterized the preceding design for the development of the hybrid multi-junction silicon germanium (HMJ-SiGe) solar cell. Seven focus areas were investigated: diffraction pattern generation, photon propagation, silicon diffusion processing, ohmic contacts, the distributed Bragg reflector (DBR), the Fresnel zone plate (FZP), and the germanium/germanium telluride (Ge/GeTe) pn-junction Diffraction patterns were theoretically examined, and contact grating design characterization for reflectance and transmittance properties was modeled using rigorous coupled wave analysis. An improved silicon diffusion process follower was developed, and theoretical study and experimental assessment were accomplished …

Dynamic Network Security Control Using Software Defined Networking, Michael C. Todd

Theses and Dissertations

This thesis develops and implements a process to rapidly respond to host level security events using a host agent, Software Defined Networking and OpenFlow updates, role based flow classes, and Advanced Messaging Queuing Protocol to automatically update configuration of switching devices and block malicious traffic. Results show flow table updates are made for all tested levels in less than 5.27 milliseconds and event completion time increased with treatment level as expected. As the number of events increases from 1,000 to 50,000, the design scales logarithmically caused mainly by message delivery time. Event processing throughput is limited primarily by the message …

Applications Of Correlated 2d-Acar And Cdbar Using A Low-Energy Positron Beam, Angelo M. Bonavita

Theses and Dissertations

The three-dimensional positron annihilation spectroscopy system (3D-PASS) at the Air Force Institute of Technology (AFIT) correlates coincidence Doppler broadening of annihilation radiation with two-dimensional angular correlation of annihilation radiation measurements using two position-sensitive, high-purity germanium (HPGe) detectors. The low photoelectric cross section of germanium, combined with the limited output of the radioisotope-based positron beam, produced sparse data necessitating careful data extraction. Processing techniques employed to increase 3D-PASS spectra quality include an improved algorithm for determining radiation-interaction position on HPGe double-sided strip detectors, a momentum sampling function based correction scheme and spectra folding informed by crystal symmetries. The 3D nature of …

Long-Term Impacts Of Military Drawdown On The Industrial Base, Anton H. Martyn

Theses and Dissertations

Since World War II, competition in the defense industry has fallen by over 90 percent. Over half of contracts currently executed by the United States Navy and Air Force are awarded without any competition. With the recent defense budget cuts, and an extended period of reduced defense spending ahead, more of which is going to sustainment and overhead than ever before, each year prime contractors are fighting over an even smaller piece of the procurement pie, which could have a deleterious effect on national security if these contractors go out of business or further consolidate through mergers. This study used …

Rate Setting Analysis: A Statistical Approach To Outlier Analysis In The Rate Setting Process Within The United States Transportation Command, Warren B. Mcgriff

Theses and Dissertations

The rate setting process implemented by the USTRANSCOM J8 Program Analysis & Financial Management Directorate (USTC J8 or TCJ8) is of importance, as accurate rates yield proper and equitable recoupment of costs from customers and ensure USTC can achieve an accurate Net Operating Result (NOR) in each given year. This research sought to identify areas in which the current rate setting methodology can be improved. We initially examined the use of six months of historical cost data versus a full year of data to set rates, concluding that there is not a statistically significant difference with respect to their relative …

Using Multiple Objective Decision Analysis To Position Federal Product And Service Codes Within The Kraljic Portfolio Matrix, Robert T. Montgomery

Theses and Dissertations

Despite the best efforts of the Federal Government to implement strategic sourcing, recent Government Accountability Office (GAO) reports highlight major procurement deficiencies and encourage the use of commercial best practices to identify and reap substantial savings. The Kraljic Portfolio Matrix (KPM) is considered the premier tool for purchasing organizations to determine which commercial best practices to utilize for different categories of spend. However, critics of the KPM point to its lack of analytical rigor and the absence of a simplistic quantitative methodology for implementation. The Air Force Installation Contracting Agency (AFICA), the centralized procurement arm for 79 USAF installations worldwide, …

Sortie Generation Simulation Of A Fighter Squadron, Abdurrahman Sevimli

Theses and Dissertations

The Turkish Air Force utilizes several fighter squadrons to enhance its military capabilities. One of the most critical challenges for these squadrons is generating sorties to meet the currency and demand during both peacetime and wartime. This sortie generation process directly affects the success of both training and operations. In this study, this process is assessed using a discrete event simulation. Air Force decision makers require a simulation tool to conduct “what-if” analysis on how potential changes in the environment affect an F-16 fighter squadron’s sortie generation process. Creating a usable simulation provides decision makers with a flexible tool to …

Measuring The Effectiveness Of Us Military Humanitarian Construction Projects Through Geospatial Analysis Of Public Opinion In Belize, Arthur Z. Dietrich

Theses and Dissertations

As part of broader US foreign policy efforts the Department of Defense (DoD) increasingly conducts complex operations which focus on efforts to influence local populations. These \hearts and minds" operations often include humanitarian and development construction projects. The wider impact on US foreign policy effort from the US military's participation in projects traditionally conducted by civilian agencies is not well understood. This research examined the effects on local public opinion from two US Air Force led \Operation New Horizons" Humanitarian and Civic Assistance (HCA) missions conducted in the nation of Belize in 2013 and 2014. The study specifically looked for …

A Service Oriented Architecture Approach For Global Positioning System Quality Of Service Monitoring, Stuart A. Everson

Theses and Dissertations

This research focuses on the development of a Service Oriented Architecture (SOA) for monitoring the Global Positioning System (GPS) Standard Positioning Service (SPS) in near real time utilizing a Mobile Crowd Sensing (MCS) technique. A unique approach to developing the MCS SOA was developed that utilized both the Depart- ment of Defense Architecture Framework (DoDAF) and the SOA Modeling Language (SoaML) guidance. The combination of these two frameworks resulted in generation of all the architecture products required to evaluate the SOA through the use of Model Based System Engineering (MBSE) techniques. Ultimately this research provides a feasibility analysis for utilization …