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Full-Text Articles in Engineering

Operational And Cost Analysis Of A Leo Radar-Based Satellite Constellation, Kyle O. Norbert Dec 2022

Operational And Cost Analysis Of A Leo Radar-Based Satellite Constellation, Kyle O. Norbert

Theses and Dissertations

This thesis presents a methodology to assess the ability of a Low-Earth Orbit (LEO) satellite constellation to successfully accomplish the GMTI mission in a cost-effective fashion. A simulation model was developed to test the coverage performance of 512 unique constellation designs. Significant factors were revealed by developing regression models that revealed the most critical constellation trade-offs on measures of performance. A Value-Focused Thinking (VFT) approach was applied to assign weights to a broad range of measures of performance from which the Pareto distribution on a cost-capability plot revealed cost-effectiveness. A novel measure of performance was developed and analyzed that accounted …


Optimal Scheduling Of Aircraft Test And Evaluation Fleets To Balance Availability For Testing And Training, Sarah E. Hoops Dec 2022

Optimal Scheduling Of Aircraft Test And Evaluation Fleets To Balance Availability For Testing And Training, Sarah E. Hoops

Theses and Dissertations

The 96th Test Wing at Eglin Air Force Base manually schedules a fleet of approximately 26 aircraft to conduct a range of missions over a one-to-two year planning period. This study automates the scheduling process, does so in a manner that optimizes multiple planning goals related to aircraft availability for training, and provides the 96th Test Wing with a software tool for the implementation that can be used by operational analysts within the command. We formulate the scheduling problem as a multiobjective, nonlinear, binary integer math program that seeks to maximize both the lowest percent of time any aircraft is …


Cooperative Wide Area Search Algorithm Analysis Using Sub-Region Techniques, Shawn Whitney Dec 2022

Cooperative Wide Area Search Algorithm Analysis Using Sub-Region Techniques, Shawn Whitney

Theses and Dissertations

Recent advances in small Unmmaned Aerial Vehicle (UAV) technology reinvigorates the need for additional research into Wide Area Search (WAS) algorithms for civilian and military applications. But due to the extremely large variability in UAV environments and design, Digital Engineering (DE) is utilized to reduce the time, cost, and energy required to advance this technology. DE also allows rapid design and evaluation of autonomous systems which utilize and support WAS algorithms. Modern WAS algorithms can be broadly classified into decision-based algorithms, statistical algorithms, and Artificial Intelligence (AI)/Machine Learning (ML) algorithms. This research continues on the work by Hatzinger and Gertsman …


Project Selection In Facility And Infrastructure Maintenance Organizations, Bayram M. Kurbanov Dec 2022

Project Selection In Facility And Infrastructure Maintenance Organizations, Bayram M. Kurbanov

Theses and Dissertations

The current Air Force Civil Engineer Center (AFCEC) built infrastructure Facility Sustainment Restoration and Modernization (FSRM) portfolio management methodology results in an unbalanced project portfolio. The consequence of this unbalance is that majority of the funding goes towards buildings on the flightline and Facility Support Services activities do not get adequate funding which leads to further deterioration of those facilities. This research investigates whether decision support framework based on Value-Focused Thinking (VFT) process yields better project selection outcomes for facility and infrastructure maintenance organizations. To accomplish that, the investigation focuses on understanding current AFCEC decision support methodology, building an alternative …


Root-Cause Analysis Of Rsaf Maintenance-Related Flight Safety Mishaps, Heaf H. Alqahtani Sep 2022

Root-Cause Analysis Of Rsaf Maintenance-Related Flight Safety Mishaps, Heaf H. Alqahtani

Theses and Dissertations

Poor maintenance is a major factor in many aviation mishaps. This is due to the fact that some maintenance activities are carried out improperly or overlooked as a result of human error. It is important to acknowledge that maintenance mistakes are a visible sign of deeper organizational issues. Therefore, adequate solutions to maintenance issues must consider organizational influences. Despite efforts to reduce the accident rate within the Royal Saudi Air Force (RSAF), the RSAF suffers from an increasing trend in mishaps attributed to maintenance. Therefore, safety data was analyzed to examine trends. Additionally, the Human Factors Analysis and Classification System …


Value Focused Thinking Analysis Of C-Band Australia Radar Operations, Samuel Ray Grothman Sep 2022

Value Focused Thinking Analysis Of C-Band Australia Radar Operations, Samuel Ray Grothman

Theses and Dissertations

The radars used for Space Domain Awareness (SDA) are inherently all-weather, day/night sensors capable of around the clock operations. Despite this fact, some radars are operated for fewer than their maximum operating capabilities. The decision-making process for selecting the operating hours of a sensor has historically been based on only a few factors or just one. This research uses the techniques in Value Focused Thinking to develop an evaluation process to score possible alternatives and find the alternative with the most value for the decision maker. By investigating the value that is added by operating an SDA radar, it is …


Evaluating Performance Competencies In The Royal Saudi Air Force Engineering Directorate And Squadrons, Faisal A. Al Dawood Sep 2022

Evaluating Performance Competencies In The Royal Saudi Air Force Engineering Directorate And Squadrons, Faisal A. Al Dawood

Theses and Dissertations

The effectiveness of tasks performed by the directorate of aeronautical engineering and squadrons in RSAF directly impacts flight safety, which in turn influences the organization either positively or negatively. Therefore, improving engineers' competencies will improve the overall performance of the organization. The study refined and reconstructed a model, namely a T-shape competency model, to assess the engineers' competencies which revealed some management and competency-related deficiencies and concluded with managerial recommendations.


Retention Prediction And Policy Optimization For United States Air Force Personnel Management, Joseph C. Hoecherl Sep 2022

Retention Prediction And Policy Optimization For United States Air Force Personnel Management, Joseph C. Hoecherl

Theses and Dissertations

Effective personnel management policies in the United States Air Force (USAF) require methods to predict the number of personnel who will remain in the USAF as well as to replenish personnel with different skillsets over time as they depart. To improve retention predictions, we develop and test traditional random forest models and feedforward neural networks as well as partially autoregressive forms of both, outperforming the benchmark on a test dataset by 62.8% and 34.8% for the neural network and the partially autoregressive neural network, respectively. We formulate the workforce replenishment problem as a Markov decision process for active duty enlisted …


A Methodological Framework For Parametric Combat Analysis, Dustin L. Hayhurst Sr. Sep 2022

A Methodological Framework For Parametric Combat Analysis, Dustin L. Hayhurst Sr.

Theses and Dissertations

This work presents a taxonomic structure for understanding the tension between certain factors of stability for game-theoretic outcomes such as Nash optimality, Pareto optimality, and balance optimality and then applies such game-theoretic concepts to the advancement of strategic thought on spacepower. This work successfully adapts and applies combat modeling theory to the evaluation of cislunar space conflict. This work provides evidence that the reliability characteristics of small spacecraft share similarities to the reliability characteristics of large spacecraft. Using these novel foundational concepts, this dissertation develops and presents a parametric methodological framework capable of analyzing the efficacy of heterogeneous force compositions …


Reconciliation, Restoration And Reconstruction Of A Conflict Ridden Country, Muhammad S. Riaz Jun 2022

Reconciliation, Restoration And Reconstruction Of A Conflict Ridden Country, Muhammad S. Riaz

Theses and Dissertations

Conflict has sadly been a constant part of history. Winning a conflict and making a lasting peace are often not the same thing. While a peace treaty ends a conflict and often dictates terms from the winners’ perspective, it may not create a lasting peace. Short of unconditional surrender, modern conflict ends with a negotiated cessation of hostilities. Such accords may have some initial reconstruction agreements, but Reconciliation, Restoration and Reconstruction (RRR) is a long term process. This study maintains that to achieve a lasting peace: 1) The culture and beliefs of the conflict nation must be continuously considered and …


A Model-Based Approach To Cubesat Propulsion And Payload Analysis, Madeline H. Johnson Jun 2022

A Model-Based Approach To Cubesat Propulsion And Payload Analysis, Madeline H. Johnson

Theses and Dissertations

Currently, there are only limited ways to increase mission success of CubeSats in terms of component and mission compatibility. The Payload Analysis Tool (PAT), developed by Air Force Institute of Technology (AFIT) students, combines the power of multiple tools to analyze payload compatibility on a single CubeSat bus. The PAT simulates a CubeSat mission with a variety of payloads to better understand how the payloads interact with the bus in terms of power, data rate, and memory, but it lacks a propulsion system. This thesis research advances the PAT by including a propulsion system which allows for increased mission time …


Developing A Model-Based Approach To Forecast A Competitor's System, Christopher A. Del Vecchio May 2022

Developing A Model-Based Approach To Forecast A Competitor's System, Christopher A. Del Vecchio

Theses and Dissertations

The purpose of this research is to develop a model-based approach to intelligence forecasting of a competitor’s system. This analysis currently uses a document-based practice to capture all knowledge of the forecast and its development. A framework of antithesis processes, or Anti-Processes, were derived from the systems engineering technical processes. This was then combined with analytical tradecraft from the field of competitive technical intelligence to build a SysML reference model, which was then applied to a small case study to enhance and refine the model. The Anti-Process framework and SysML reference model provide a rigorous, model-based approach to intelligence forecasts …


A Thematic And Reference Analysis Of Touchless Technologies, Eric R. Curia Mar 2022

A Thematic And Reference Analysis Of Touchless Technologies, Eric R. Curia

Theses and Dissertations

The purpose of this research is to explore the utility and current state of touchless technologies. Five categories of technologies are identified as a result of collecting and reviewing literature: facial/biometric recognition, gesture recognition, touchless sensing, personal devices, and voice recognition. A thematic analysis was conducted to evaluate the advantages and disadvantages of the five categories. A reference analysis was also conducted to determine the similarities between articles in each category. Touchless sensing showed to have the most advantages and least similar references. Gesture recognition was the opposite. Comparing analyses shows more reliable technology types are more beneficial and diverse.


Training Logic And Random Forest Models To Predict It Spending, Jacob P. Batt Mar 2022

Training Logic And Random Forest Models To Predict It Spending, Jacob P. Batt

Theses and Dissertations

The Air Force must modernize, but the distribution of funds for technology remains as tight as ever. To this end, the Air Force Audit Agency is looking to utilize machine learning techniques to enhance their capabilities. This research explores Logistic Regression and Random Forest modeling to streamline data collection and cost classification. The final Logistic Regression model identified 4 significant attributes out of the 36 given and was 85 accurate in predicting whether a purchase amount was over or under $10,000. To expand beyond binary classification, a six-category classification Random Forest model was developed. It identified 6 significant attributes and …


Multiagent Routing Problem With Dynamic Target Arrivals Solved Via Approximate Dynamic Programming, Andrew E. Mogan Mar 2022

Multiagent Routing Problem With Dynamic Target Arrivals Solved Via Approximate Dynamic Programming, Andrew E. Mogan

Theses and Dissertations

This research formulates and solves the multiagent routing problem with dynamic target arrivals (MRP-DTA), a stochastic system wherein a team of autonomous unmanned aerial vehicles (AUAVs) executes a strike coordination and reconnaissance (SCAR) mission against a notional adversary. Dynamic target arrivals that occur during the mission present the team of AUAVs with a sequential decision-making process which we model via a Markov Decision Process (MDP). To combat the curse of dimensionality, we construct and implement a hybrid approximate dynamic programming (ADP) algorithmic framework that employs a parametric cost function approximation (CFA) which augments a direct lookahead (DLA) model via a …


Bayesian Convolutional Neural Network With Prediction Smoothing And Adversarial Class Thresholds, Noah M. Miller Mar 2022

Bayesian Convolutional Neural Network With Prediction Smoothing And Adversarial Class Thresholds, Noah M. Miller

Theses and Dissertations

Using convolutional neural networks (CNNs) for image classification for each frame in a video is a very common technique. Unfortunately, CNNs are very brittle and have a tendency to be over confident in their predictions. This can lead to what we will refer to as “flickering,” which is when the predictions between frames jump back and forth between classes. In this paper, new methods are proposed to combat these shortcomings. This paper utilizes a Bayesian CNN which allows for a distribution of outputs on each data point instead of just a point estimate. These distributions are then smoothed over multiple …


Geometric Generation Through The Merging Of Sysml, And Engineering Sketch Pad, Alexander J. Miesle Mar 2022

Geometric Generation Through The Merging Of Sysml, And Engineering Sketch Pad, Alexander J. Miesle

Theses and Dissertations

The United Stated Department of Defense (DoD) and Air Force (USAF) have placed increased emphasis on the utilization of modern systems engineering (SE) practices within the current and future acquisitions lifecycle. This call is driven by the current rate at which near-peer adversaries such as Russia and China are increasing their defense system capabilities and catching up or surpassing the Unites States in certain operational regions. To aid in the transition to a Digital Engineering and Digital Twin dominated acquisitions process, this thesis presents a method with which SysML and geometric tools can be linked within both new and existing …


Analyzing The Impact Of Blood Transfusion Kits And Triage Misclassification Errors For Military Medical Evacuation Dispatching Policies Via Approximate Dynamic Programming, Channel A. Rodriguez Mar 2022

Analyzing The Impact Of Blood Transfusion Kits And Triage Misclassification Errors For Military Medical Evacuation Dispatching Policies Via Approximate Dynamic Programming, Channel A. Rodriguez

Theses and Dissertations

Members of the armed forces greatly rely on having an effective and efficient medical evacuation (MEDEVAC) process for evacuating casualties from the battlefield to medical treatment facilities (MTF) during combat operations. This thesis examines the MEDEVAC dispatching problem and seeks to determine an optimal policy for dispatching a MEDEVAC unit, if any, when a 9-line MEDEVAC request arrives, taking into account triage classification errors and the possibility of having blood transfusion kits on board select MEDEVAC units. A discounted, infinite-horizon continuous-time Markov decision process (MDP) model is formulated to examine such problem and compare generated dispatching policies to the myopic …


Analysis Of The Perspective On Syrian Refugees By Neighboring Countries, Norma Ghanem Mar 2022

Analysis Of The Perspective On Syrian Refugees By Neighboring Countries, Norma Ghanem

Theses and Dissertations

Mass migration destabilizes neighboring states, opening the way for fragile state exploitation by enemies, including those that could undermine U.S. national interests. This study investigates an area of the Levant region, specifically countries neighboring Syria, and analyzes their perspective on Syrian refugees for the time frame of 1 June 2019 - 30 June 2020. This analysis may assist in forming policy and creating strategies to address refugee related issues, both domestic and international. There are three main questions addressed. The first inspects dominant refugee framing, the second explores sentiment (dis)similarity within each country and across countries, and the third investigates …


Analysis Of Container Shipments For Ustranscom, John N. Campos Y Campos Mar 2022

Analysis Of Container Shipments For Ustranscom, John N. Campos Y Campos

Theses and Dissertations

USTRANSCOM (United States Transportation Command) sends containers to various overseas destinations, mainly commercial container shipping companies. Delivering the containers to the destinations on time is important to support the United States (US) Forces deployed in foreign countries. This study analyzes container shipment records for two years from 2019 to 2021 and prepares insights for USTRANSCOM. This study utilizes descriptive statistics, data visualization, and one-way analysis of variance (ANOVA). According to the records, almost half of the containers (41.25%) were delivered late for one day or longer. The container with the longest delay took 408 days. Major reasons for delays included …


Military Personnel Flight Customer Wait Time Reduction Model Using Simulation, Nicholas C. Anderson Mar 2022

Military Personnel Flight Customer Wait Time Reduction Model Using Simulation, Nicholas C. Anderson

Theses and Dissertations

Customers at Military Personnel Flights (MPFs) have been experiencing long wait times. These customers are typically employees of the United States Air Force and every moment spent waiting for service is a moment they are away from their actual jobs. By reducing the mean wait time of MPF customers, manhours can be saved and customer complaints may be alleviated. This research uses data collected from an MPF to build a discrete-event simulation model of an MPF. A full factorial experimental design was conducted in the model using five factors. The factors included the total number of employees, the total number …


Evaluating The Military Medical Evacuation Dispatching And Delivery Problem Via Simulation And Self-Exciting Hawkes Process, Virbon B. Frial Mar 2022

Evaluating The Military Medical Evacuation Dispatching And Delivery Problem Via Simulation And Self-Exciting Hawkes Process, Virbon B. Frial

Theses and Dissertations

The location, allocation, and utilization of military medical evacuation (MEDEVAC) resources significantly impact the quality and timeliness of medical care to injured troops. In 2009, Secretary of Defense Robert Gates introduced the Golden Hour mandate that entails the evacuation of critically-injured troops to military treatment facilities (MTFs) within an hour to prevent further complications. To develop high-quality policies that improve MEDEVAC system performance, several papers in the current literature assume that MTFs have both the capacity and capability of treating any patient, regardless of the type of injury. However, these assumptions are unrealistic when conducting high-intensity operations. While acknowledging MTF …


The Impact Of Visual Feedback And Control Configuration On Pilot-Aircraft Interface Using Head Tracking Technology, Christopher M. Arnold Mar 2022

The Impact Of Visual Feedback And Control Configuration On Pilot-Aircraft Interface Using Head Tracking Technology, Christopher M. Arnold

Theses and Dissertations

Traditional control mechanisms restrict human input on the displays in 5th generation aircraft. This research explored methods for enhancing pilot interaction with large, information dense cockpit displays; specifically, the effects of visual feedback and control button configuration when augmenting cursor control with head tracking technology. Previous studies demonstrated that head tracking can be combined with traditional cursor control to decrease selection times but can increase pilot mental and physical workload. A human subject experiment was performed to evaluate two control button configurations and three visual feedback conditions. A Fitts Law analysis was performed to create predictive models of selection time …


Narrative Analysis Of Open-Source Social Media Activity In The Indopacom Aor, Aaron K. Glenn Mar 2022

Narrative Analysis Of Open-Source Social Media Activity In The Indopacom Aor, Aaron K. Glenn

Theses and Dissertations

Emotion classification can be a powerful tool to derive narratives from social media data. Recurrent Neural Networks (RNN) can meet or exceed the performance of state-of-the-art traditional machine learning techniques using exclusively open-source data and models. Specifically, these results show that RNN variants can produce more than an 8% gain in accuracy in comparison to Logistic Regression and SVM techniques and a 15% gain over Random Forest when using FastText embeddings. This research found a statistical significance in the performance of a single layer Bi-directional Long Short-Term Memory (Bi-LSTM) model over a 2-layer stacked Bi-LSTM model. This research also found …


Optimal Aircraft Maneuvering Models For Cruise Missile Engagement: A Modeling And Computational Study, Izaiah G. Laduke Mar 2022

Optimal Aircraft Maneuvering Models For Cruise Missile Engagement: A Modeling And Computational Study, Izaiah G. Laduke

Theses and Dissertations

Given the increased threat and proliferation of adversary military capabilities, this research seeks to develop reasonably accurate and computationally tractable models to optimally maneuver aircraft to intercept cruise missile attacks. The research leveraged mathematical programming to model the problem, informed by constraints representing a system of (temporal) difference equations. The research began by comparing six models having alternative representations of velocity and acceleration constraints while analyzing situations with stationary targets. The Multiple Aircraft, Multiple Stationary Target Engagement Problem with Box Constraint Bounds (MAMSTEP-BC) Model yielded superior overall performance and was further analyzed through alternative mathematical programming model enhancements to create …


Comparison Of Lightning Warning Radii Distributions, Michael M. Maestas Mar 2022

Comparison Of Lightning Warning Radii Distributions, Michael M. Maestas

Theses and Dissertations

Previous research investigating lightning warning radii about the Cape Canaveral space launch facilities have focused on reducing these radii from either 5 nautical miles (NM) to 4 NM or from 6 NM to 5 NM depending on the structures being protected. Some of these findings have suggested the possibility of both a seasonal difference (warm versus cold) and lightning detection events (cloud-to-ground lightning (CG) or total lightning (TL)) impacting these radii and associated risk levels. Utilizing the 2017-2020 data provided by the 45th Weather Squadron at Patrick Space Force Base via the Mesoscale Eastern Range Lightning Information System (MERLIN), this …


An Exploratory Analysis Of Time Series Econometric Data For Retention Forecasting Using Deep Learning, John C. O'Donnell Mar 2022

An Exploratory Analysis Of Time Series Econometric Data For Retention Forecasting Using Deep Learning, John C. O'Donnell

Theses and Dissertations

Officer retention in the Air Force has been researched many times in an attempt to better predict the personnel needs of the Air Force for the future. There has been previous work done in regards to specific AFSCs and how their retention compares to specific yet similar private sector jobs. This study considers different econometric time series statistics as a feature space and an average Air Force officer separation rate as the response variable for the multivariate time series analysis deep learning techniques. The econometric indicators used in this study are New Business Formations, New Durable Good Orders, and the …


Predicting Tf33-Pw-100a Engine Failures Due To Oil Issues Using Survival Analyses, Anna M. Davis Mar 2022

Predicting Tf33-Pw-100a Engine Failures Due To Oil Issues Using Survival Analyses, Anna M. Davis

Theses and Dissertations

In 2007, the Office of the Assistant Secretary of Defense for Sustainment pushed for the need to transition to a Condition Based Maintenance Plus (CBM ) initiative for weapon systems in the U.S. Department of Defense. The CBM initiative can help increase aircraft availability (AA) for the United States Air Force. There are many reasons where AA can be affected but one such issue is engine availability primarily due to oil issues. Within the CBM perspective, this study examines the risk of a jet engine failure due to an oil issue and attempts to predict an engines time until next …


The Cyber Wargame Commodity Course Of Action Automated Analysis Method, Alex Hoffendahl Mar 2022

The Cyber Wargame Commodity Course Of Action Automated Analysis Method, Alex Hoffendahl

Theses and Dissertations

In the modern operational landscape, strategic decisions are made and executed, under uncertain conditions, with many potential constraints and limited information. The end goal of these decisions is to minimize and mitigate the effect of adversarial threats, which may or may not act in line with previous assumptions. Wargaming is a powerful tool that allows for the practical implementation of theoretical knowledge into real-world scenarios, enhancing decision-makers critical thinking and problem solving skills. Furthermore, including cyber-effects in a wargame leads to a broader decision scope for an entire operation. This research aims to enhance the analytical capabilities and overall usability …


Networked Cooperative Autonomous Munitions Digital Twin Modeling Utilizing Model Based Systems Engineering, Christopher R. Reed Mar 2022

Networked Cooperative Autonomous Munitions Digital Twin Modeling Utilizing Model Based Systems Engineering, Christopher R. Reed

Theses and Dissertations

An example of a high-complexity system is a swarm of Networked Cooperative Autonomous Munitions (NCAM) that prioritize wide area search and multiple view target confirmation. First, this research discusses methods toward building behavioral models within a Model-Based Systems Engineering (MBSE) tool. Then, this research presents the parallel modeling effort of NCAM in two environments: the MBSE model in Cameo Systems Modeler, and a physics-based model in the Advanced Framework for Simulation, Integration, and Modeling (AFSIM). Each digital model in its environment provides distinct benefits to the stakeholders of the design process, so the models must present consistent and parallel information. …