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Full-Text Articles in Engineering

Validation Of Digital System Models, James R. Winton Mar 2023

Validation Of Digital System Models, James R. Winton

Theses and Dissertations

The Department of Defense is undergoing a Digital Transformation driven by Digital Engineering and Model-Based Systems Engineering. Document-based processes are being replaced by digital artifacts, pedigreed data, and an Authoritative Source of Truth for a system across its life cycle. As traditional Design-Build-Test transitions to a Model-Analyze-Build methodology, digital models will proliferate throughout the enterprise and require novel validation processes earlier in the development timeline. A new definition for digital system model validation is proposed to address the identified shortcomings in existing guidance. The proposed validation framework leverages the Systems Modeling Language, use cases, requirements, test cases, and a custom …


A Systems Modeling Approach To Support Human-Agent Team Performance For Combat Identification, Clayton W. Couch Mar 2023

A Systems Modeling Approach To Support Human-Agent Team Performance For Combat Identification, Clayton W. Couch

Theses and Dissertations

Combat Identification (CID) in an air-to-air combat context is a highly complex cognitive task that requires the operator to make rapid, high consequence decisions. To accomplish CID, fighter aircrew must attend to and perceive a broad range of information while concurrently building situation awareness (SA) and conducting other tasks. While existing automated agents are available to help fighter aircrew with this CID task, they are designed for a very narrow subset of the overall task and are not well suited for human-agent teaming. An interdependence analysis of the human operator and supporting machine agents conducted for this task support the …


An Analysis Of A Modular Open System Approach On Program Management Metrics For Cost And Schedule, Kayla I. Vogler Mar 2023

An Analysis Of A Modular Open System Approach On Program Management Metrics For Cost And Schedule, Kayla I. Vogler

Theses and Dissertations

A modular open system approach (MOSA) and its inclusion of open architecture are among the prevailing acquisition strategies for cost and schedule management. This approach involves the incorporation of reusable, modular packages that can be incrementally added and upgraded throughout programs’ lifecycles. Many practitioners throughout the acquisitions community find that MOSA enables better opportunities for affordability, rapid acquisition, flexibility, enhanced competition, and innovation. A literature review reveals that few studies examine the interaction between MOSA and the extent to which it influences cost and schedule performance. However, no studies to date examine open architecture’s impact via programmatic evaluation of Earned …


Integrating Ace And Mca Requirements Into The Civil Engineer Officer Occupational Competency Framework, Stone D. Williford Mar 2023

Integrating Ace And Mca Requirements Into The Civil Engineer Officer Occupational Competency Framework, Stone D. Williford

Theses and Dissertations

The Air Force Civil Engineer officer career field has made dedicated efforts to the professional development of its company grade officers. In response to the 2015 Air Force Strategic Master plan, the Civil Engineer officer career field adopted a competency-based education approach. In 2020, the Civil Engineer Officer Career Field Education and Training Plan was published, officially integrating the career field’s operational requirements into a competency framework. However, since 2020, the Air Force has adopted an updated force generation strategy, and with it, changes to the way the Air Force assets are employed in contingency environments. This new scheme of …


Critical Infrastructure System Resiliency Modeling Using Multi-Layer Network Optimization, Spencer R. Figge Mar 2023

Critical Infrastructure System Resiliency Modeling Using Multi-Layer Network Optimization, Spencer R. Figge

Theses and Dissertations

ccurately modeling the interdependent operation of critical infrastructure systems is an effective and efficient way of proactively evaluating system vulnerabilities and resiliency. Infrastructure systems are designed to transport essential commodities from where they are produced to where they are consumed and network flow-based models are one of the most effective ways to simulate and quantify infrastructure performance. The literature is populated with proposed models that must balance accuracy of interdependent operations, capability to include real-world considerations, and computational cost. This research proposes an alternative network-flow based model called the Critical Infrastructure System Resiliency Model (CISRM) that focuses on modeling a …


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 …


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 …


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 Decadal Analysis Of Shifts In Engineering Manufacturing Development Factors For Dod Assets, Michael J. Smith Mar 2022

A Decadal Analysis Of Shifts In Engineering Manufacturing Development Factors For Dod Assets, Michael J. Smith

Theses and Dissertations

This research involves the analysis of standard parametric factors by decade within the development stage of acquisitions. Analysts use factors to develop budgets, create a baseline for measuring project progress, or as a crosscheck to the other estimating techniques. This research analyzed data from 408 1921s across seven decades and eight work breakdown structure (WBS) elements. It further analyzed these decades by commodity type, contract and contractor type, and service branch. The statistical tests used in this research determined which decades within our categories were dissimilar and drew conclusions about the impact of those differences. These tests determined that factors …


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 …


Improving Task-Operator Analysis For Training Through The Integration Of Human Learning Taxonomies And Systems Engineering Models, James M. Earley Mar 2022

Improving Task-Operator Analysis For Training Through The Integration Of Human Learning Taxonomies And Systems Engineering Models, James M. Earley

Theses and Dissertations

Training is a critical part of force sustainment, but the life-cycle cost of recurring training can be quite high. Further, the promotion of the Multi-Capable Airman (MCA) concept leads to questions on how best to train airmen on tasks outside of their core career field. The MCA concept, coupled with continued increase of technology effectiveness, incentivize the replacement of formerly in-residence-only training with distance training that enables Just-in-Time (JIT) learning. However, effective implementation of the MCA concept may also require adaptive training which considers the knowledge, skills, and attitudes (KSAs) developed by a trainee within their core career field when …


Characterizing Complex-Valued Neural Network Model Approximations Of 4-Input 4-Output Complex-Valued Reference Block Models, Larry C. Llewellyn Ii Mar 2022

Characterizing Complex-Valued Neural Network Model Approximations Of 4-Input 4-Output Complex-Valued Reference Block Models, Larry C. Llewellyn Ii

Theses and Dissertations

System simulation models are often decomposed and abstracted as a collection of interconnected subsystem block models to facilitate system understanding, design, and analysis. Each subsystem block model contains mathematical functions that receive, process, and transmit signals that are modeled as real numbers, complex numbers, and/or logic values. This dissertation evaluates the use of a single two-layer complex-valued neural network model to approximate 4-input, 4-output subsystem reference block models in terms of accuracy, performance, and error. The research is novel in that it uses a neural network for continuous function approximation instead of data categorization; it uses a neural network designed …


A Proposed Mission Assurance Framework For University Cubesat Programs, Mitchell R. Thomas Mar 2022

A Proposed Mission Assurance Framework For University Cubesat Programs, Mitchell R. Thomas

Theses and Dissertations

The low cost, small form factor, and use of Commercial-Off-The-Shelf components make CubeSats an ideal platform for university use given their unique constraints. Since 2000, roughly 55% of CubeSats developed by universities fail to meet mission goals. Mission assurance, which is used to increase confidence in mission success, is based around traditional government programs, and does not provide an adequate road map for universities. Leaving them without specific guidance in tailoring mission assurance activities to operate within their constraints. This paper adapts these traditional practices to develop a baseline mission assurance framework for university CubeSat programs.


Exploring The Value Of Training System Alternatives Through Methods Technologies, And Relevant Attributes, Brian R. Novitsky Mar 2022

Exploring The Value Of Training System Alternatives Through Methods Technologies, And Relevant Attributes, Brian R. Novitsky

Theses and Dissertations

Skilled maintainers are being lost at a higher rate than average of all enlisted career fields within the Air Force. Although incentive programs can provide some retention, attrition rates may continue to vary, placing the readiness of the warfighter in jeopardy. Additionally, the technologies used to train maintainers have evolved substantially, including augmented reality (AR) and virtual reality (VR) solutions, among others. These technologies have recently gained notoriety as novel ways to increase training effectiveness, providing avenues for maintainers to achieve greater skill levels at a faster rate than traditional platforms. Through semi-structured subject matter expert (SME) interviews, this qualitative …


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.


Accelerating Transition To Production By Manufacturing Readiness Focus During Development, William K. Duncan Mar 2022

Accelerating Transition To Production By Manufacturing Readiness Focus During Development, William K. Duncan

Theses and Dissertations

The Department of Defense has adopted management tools, such as Manufacturing Readiness Levels (MRLs), which seek to address issues that have delayed the transition to production and delivery of deployment-ready systems. The MRL scale and assessment process institutes periodic reviews of products during the acquisition process. Specifically, MRLs provide a scale to measure, and importantly communicate, progress by evaluating and summarizing multiple aspects of product maturity. Unfortunately, issues are often identified during the periodic assessments which, if addressed earlier, would have further streamlined product delivery. The current research applies Model Based System Engineering tools to analyze and refine organizational structures …


Development And Assessment Of A Model-Based Framework On User Toolkits, Brandon J. Koury Mar 2022

Development And Assessment Of A Model-Based Framework On User Toolkits, Brandon J. Koury

Theses and Dissertations

The Department of Defense (DoD) has a limited number of resources to accomplish a variety of missions which involve deploying personnel to support and maintain aircraft operating throughout the world. The DoDs maintenance structure codes maintainers to perform maintenance on specific airframes. This structure limits the flexibility of maintainers and leads to deploying resources in a reactionary manner to address capability gaps in deployed environments. The Just-In-Time Multi-Mission Airman (JIT MMA) concept aims to resolve these issues. Currently, the necessary technologies are unknown, but user toolkits are a concept to consider. A user toolkit is a concept that allows users …


Quantifying Project Complexity To Resource Project Managers, Jereme R. Henrard Mar 2022

Quantifying Project Complexity To Resource Project Managers, Jereme R. Henrard

Theses and Dissertations

This research develops a multi-criteria decision analysis model to quantify project complexity and inform decision-makers in resource-constrained organizations with the Tyndall Program Management Office (PMO) as a case study. The complexity score is used as a risk metric to determine the appropriate number of skilled or novice project managers to effectively manage the PMO portfolio to mitigate cost and schedule overruns. The research provides an innovative approach to consider manning levels at the PMO and other project management-focused organizations/sections.


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. …


Machine Learning Application For Mission Data Reprogramming, Paolo A. Bingham Dec 2021

Machine Learning Application For Mission Data Reprogramming, Paolo A. Bingham

Theses and Dissertations

Before entering a conflict or theater, USAF aircraft require updated mission data software reprogramming. Mission data controls all electronic warfare (EW) operations of the aircraft. EW operations include identifying and jamming radar operated systems, whether they are friendly or hostile. The process of reprogramming software is continuous and routinely updated for every EW system annually. On specific circumstances, the process can be expedited to months, but this puts a strain on the development team and shifts all attention to one specific mission data file. Unfortunately, a growing number of requests to upgrade mission data to a higher priority state, has …


Meta-Analysis Of Performance Characteristics Of Modern Database Schemas, Carter Grove Dec 2021

Meta-Analysis Of Performance Characteristics Of Modern Database Schemas, Carter Grove

Theses and Dissertations

Industry and academia alike are more commonly using databases as solutions to advanced and complex problems. Unfortunately, not all database schemas are created equal and can yield different advantages in different areas. To try to understand what database schema might be best suited for a user’s needs, we sought out to distinguish how databases are measured against each other, what their performance characteristics are, and what advantages each type of database inherently possesses. To allow for the ingestion of data across the five different categories of database schemas, we used a met-analysis of past literature and aggregated the data to …


Assessment Of Visual Field Performance Asymmetries While Utilizing Aircraft Attitude Symbology, George A. Reis Dec 2021

Assessment Of Visual Field Performance Asymmetries While Utilizing Aircraft Attitude Symbology, George A. Reis

Theses and Dissertations

Two experiments were conducted to examine visual performance asymmetries when perceiving complex, meaningful visual stimuli, such as the Arc Segment Attitude Reference (ASAR). The ASAR symbology represents an aircraft’s attitude. Experiment 1 examined participants’ performance while recalling and reporting various attitudes of ASAR symbology and a Gabor patch, which were briefly presented in the peripheral visual field. Performance was assessed for coordinate and categorical judgments at various display locations. The results were consistent with the horizontal-vertical anisotropy literature, which implies that performance would be better for stimuli placed on the horizontal meridian as compared to stimuli placed on the vertical …


The Effect Of Information Acquisition Automation And Workspace Design On Human Pattern Recognition For Information Fusion, Kellie L. Turner Dec 2021

The Effect Of Information Acquisition Automation And Workspace Design On Human Pattern Recognition For Information Fusion, Kellie L. Turner

Theses and Dissertations

Automation employed in information fusion systems is designed to help humans combine information derived from multiple sources to form a cohesive assessment of the situation. Research using the Levels of Automation model (Parasuraman, Wickens, and Sheridan, 2000) have produced conflicting results, which Patterson (2017) posited was because it focused solely on analytical processing while neglecting the effects of intuitive cognition. The present study examined how information acquisition automation affects the human’s ability to detect patterns in data needed to reach higher levels of information fusion. Results showed that when information acquisition was performed through manual operations, pattern recognition performance was …


Collaborative All-Source Navigation With Integrity, Jonathon S. Gipson Sep 2021

Collaborative All-Source Navigation With Integrity, Jonathon S. Gipson

Theses and Dissertations

The novel ARMAS-SOM framework fuses collaborative all-source sensor information in a resilient manner with fault detection, exclusion, and integrity solutions recognizable to a GNSS user. This framework uses a multi-filter residual monitoring approach for fault detection and exclusion and is augmented with an additional "observability" EKF sub-layer for resilience. We monitor the a posteriori state covariances in this sub-layer to provide intrinsic awareness when navigation state observability assumptions required for integrity are in danger. This is used to selectively augment the framework with offboard information to preserve resilience. By maintaining split parallel collaborative and proprioceptive estimation instances and employing a …


Interdependent Infrastructure Recovery Using Multilayered Networks And Optimization, Brigham A. Moore Sep 2021

Interdependent Infrastructure Recovery Using Multilayered Networks And Optimization, Brigham A. Moore

Theses and Dissertations

Interdependent infrastructure recovery modeling and simulation are complicated due to various interdependent connections and complexities. Current efforts have identified both operational and restoration interdependency subtypes and coupling strategies that have not been integrated into one comprehensive model. This research presents a model which simultaneously integrates nine interdependency subtypes and four coupling strategies in a multi-objective format to provide the most tailorable and comprehensive network-based recovery model available. This research also created a defense-centric interdependent infrastructure database by modifying the existing CLARC database. This research then addressed assumptions regarding recovery work management in order to address the impact of work crew …


Applying Model-Based Systems Engineering And Fidelity Quantification To Support Fair Fight In A Distributed Simulation System, Nathaniel Erbe, David Lemmer Sep 2021

Applying Model-Based Systems Engineering And Fidelity Quantification To Support Fair Fight In A Distributed Simulation System, Nathaniel Erbe, David Lemmer

Theses and Dissertations

Current 5th and 6th generation fighter aircraft capabilities, and the DoD's push towards digital engineering have created an environment in which simulated testing using live, virtual, and constructive assets has increasing utility. These simulations need to be credible in the eyes of the stakeholders, which for distributed simulation systems includes establishing fair fight between simulation services. Fair fight is when multiple simulations interoperate without generating one-sided systematic advantages. Issues that impede fair fight can be categorized into interoperability issues at the simulations implementation level and incompatible representations of reality between underlying models. This research used model-based systems engineering to generate …


Requirements Analysis And Architecture For An Operational Study Of Fatigue In Usaf Mobility Aircrew, Jonathan F. Mecham Sep 2021

Requirements Analysis And Architecture For An Operational Study Of Fatigue In Usaf Mobility Aircrew, Jonathan F. Mecham

Theses and Dissertations

Aircrew fatigue in flight operations is a known hazard that has driven the creation of fatigue-reducing regulation and fatigue risk management systems industry wide. In addition, biomathematical models have been created and tested to forecast the effectiveness of aircrew under conditions of time-zone shifts and long duty days. However, limited operational studies exist to validate these models or to help understand how individual factors can affect them. Operational studies have a variety of limitations that make gathering typical data regarding fatigue or sleep difficult. This research takes systems requirement analysis approach to design a study that measures effects of circadian …


Evaluating The Impact Of Culture On Customer Satisfaction For Fms Projects, Yaquari A. Adams Ii Mar 2021

Evaluating The Impact Of Culture On Customer Satisfaction For Fms Projects, Yaquari A. Adams Ii

Theses and Dissertations

The cost, time, and quality pillars of the iron triangle in project management are often considered the most important factors for managers to consider when striving to achieve project success. However, recent literature suggests customer satisfaction and end-user benefit are the most important elements to prioritize during project development. This research analyzes the Air Force Security Assistance Center Construction Division and Foreign Military Sales (FMS) joint construction operations in relation to two Project Management Body of Knowledge (PMBOK) knowledge areas, project stakeholder management and project risk management. Project stakeholder management is addressed by identifying the relationship between cultural competency and …


Optimizing Cost And Performance Of Infrastrucure Alternatives At Contingency Bases In A Hub-And-Spoke Network, Kyle J. Rodriguez Mar 2021

Optimizing Cost And Performance Of Infrastrucure Alternatives At Contingency Bases In A Hub-And-Spoke Network, Kyle J. Rodriguez

Theses and Dissertations

Military contingency bases require substantial resources and funding sustain and are often not connected to an infrastructure grid. Infrastructure assets produce the required outputs for sustainment, but are often expensive and inefficient, producing a significant logistical burden. With the increasing near-peer threats of opposing military forces, there is a need for more self-sufficient contingency bases with alternatives that reduce resources usage and the cost of sustainment. Accordingly, the goal of this research is to develop an optimization model capable of selecting infrastructure alternative combinations that minimize the overall resource usage and cost of sustainment at the contingency base level.