Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 31 - 60 of 195

Full-Text Articles in Engineering

Investigation Of An Avionics Part Deficiencies In Royal Saudi Air Force Fleets, Nasser S. Alanazi Sep 2020

Investigation Of An Avionics Part Deficiencies In Royal Saudi Air Force Fleets, Nasser S. Alanazi

Theses and Dissertations

The Royal Saudi Air Force (RSAF) is experiencing a shortage in certain avionics parts due to a lack of reliability. This issue is causing a supply chain disturbance in the F1-15 fleet and the Hawk fleet. One of the factors behind this problem is the environmental effects in Saudi Arabia .The study will investigate and analyze the methods for the Improvement Cycle Processes and the Quality Management within the RSAF repair cycle. Finding show that, the discrepancies are rising during summer and fall time due to the environment change, Other finding were addressed in the study.


Aligning Performance Management Systems For Lasting Outcomes In Humanitarian Operations, Kalyn M. Howard Sep 2020

Aligning Performance Management Systems For Lasting Outcomes In Humanitarian Operations, Kalyn M. Howard

Theses and Dissertations

Logistics is dynamic, expansive, and critical to organizational success. While it is generally believed that effective logistics management is associated with positive performance outcomes, the links between organizational practice and performance are understudied. This dissertation leverages resource-based theory and organizational learning theory to examine organizational practice and performance in non-traditional logistics settings, with particular focus on military organizations and humanitarian operational settings. First, a meta-analytical study establishes generalizable associations between various operations management practices and performance outcomes. Then, this is applied to dynamic humanitarian logistics settings, exploring how practitioners perceive practice and performance, and how this is reported and documented …


Sortie-Based Aircraft Component Demand Rate To Predict Requirements, Thomas R. O'Neal Mar 2020

Sortie-Based Aircraft Component Demand Rate To Predict Requirements, Thomas R. O'Neal

Theses and Dissertations

Weapon System Sustainment (WSS) costs are growing at an increasing rate despite the vast efforts to reduce them. Researchers have attributed much of the cost increase to inaccurate demand forecasts for weapon system spare parts. In 2011, the forecast to sustain all United States Air Force (USAF) aircraft was 19% accurate and WSS costs per year have continuously increased. The purpose of this study is to explore a parsimonious change to aircraft component forecasting to reduce costly forecast error. This study substitutes flying hours with sorties for the purpose of demand forecasting. Many F-16 and B-52 spare parts are evaluated …


Resilient Aircraft Sustainment: Quantifying Resilience Through Asset And Capacity Allocation, Zachary B. Shannon Mar 2020

Resilient Aircraft Sustainment: Quantifying Resilience Through Asset And Capacity Allocation, Zachary B. Shannon

Theses and Dissertations

Decision makers lack a clear, generalizable method to quantify how additional investment in inventory and capacity equates to additional levels of resilience. This research facilitates a deeper understanding of the intricacies and complex interconnectedness of organizational supply chains by monetarily quantifying changes in network resilience. The developed Area under the Curve metric (AUC) is used to quantify the level of demand that each asset allocation can meet during a disruptive event. Due to its applicability across multiple domains, the USAF F-16 repair network in the Pacific theater (PACAF) is modeled utilizing discrete event simulation and used as the illustrating example. …


An Investigation Into Subject Matter Expert Elicitation In Cost Risk Analysis, Christopher W. Miller Mar 2020

An Investigation Into Subject Matter Expert Elicitation In Cost Risk Analysis, Christopher W. Miller

Theses and Dissertations

This research compares the efficacy of subject matter expert (SME) elicitation methods to other cost estimation methods using a development and production dataset provided by AFLCMC/FZC. First, by using descriptive statistics to evaluate low versus high amount of the respective cost estimation methods by analyzing the means of percent cost growth for both groups. Next, this research involved using a statistics-based approach to investigate whether SME based cost estimating methods have an associated relationship to percent change of Program Acquisition Unit Costs (PAUC), which will be our proxy variable to cost growth. Using a pooled cross-sectional OLS regression analysis model …


Investigating Lifecycle Costs Of Optimized Battery-Photovoltaic Systems On A Forward Operating Base, Neal S. Fennell Mar 2020

Investigating Lifecycle Costs Of Optimized Battery-Photovoltaic Systems On A Forward Operating Base, Neal S. Fennell

Theses and Dissertations

The purpose of this research was to investigate the total life-cycle cost of using utility-scale battery systems to increase the energy efficiency of forward operating bases, thereby reducing the burden of diesel fuel logistics. Specifically, this thesis answered three research questions addressing optimal sizing for various battery types connected with photovoltaic grids, logistical parameters directly impacting total cost, and the cost of increasing the energy resilience of the network. The research questions were answered through a review of literature, modeling, and data analysis. The model determines an optimal size and area for a Vanadium redox flow, Lithium-ion, or Lead-acid battery …


Inherent Jeopardy Of Performance Based Contracting Metrics: A Simulation Experiment, Daniel Cherobini Mar 2020

Inherent Jeopardy Of Performance Based Contracting Metrics: A Simulation Experiment, Daniel Cherobini

Theses and Dissertations

There is a growing trend across the world to adopt Performance Based Contracting strategies to support logistics systems. Using these policies, contract payments are strongly related to the performance achieved compared to prespecified metrics. However, managers are not always confident on what are the most suitable performance goals to use in these agreements. As a consequence, contractors struggle to deliver the desired performance results, while aircraft fleets experience an increase in support costs. And when the results are inadequate, leaders are tempted to impose even more performance targets to contractors, willing to exercise more control over the support organization. In …


Undergraduate Pilot Training Attrition: An Analysis Of Individual And Class Composition Component Factors, Christina M. Akers Mar 2020

Undergraduate Pilot Training Attrition: An Analysis Of Individual And Class Composition Component Factors, Christina M. Akers

Theses and Dissertations

The Air Force is working hard to reduce the shortage of nearly 2,000 pilots that threatens the Air Force’s core mission. Officials have focused on increasing retention and training throughput. Despite this, the first Pilot Training Next class graduated in August of 2018 with 13 of the initial 20 students (65.5% graduation rate). The purpose of this research is to explore attrition reduction by understanding how class composition of individual abilities and personalities affects the class graduation rate. Using AFOQT scores, SDI+ scores, PCSM scores, flight hours, and college GPAs, correlations were studied and a simple linear regression was run …


Preliminary Study Of Communication Network Characterization Towards Improved Organizational Behavior, Taylor F. Flaxington Mar 2020

Preliminary Study Of Communication Network Characterization Towards Improved Organizational Behavior, Taylor F. Flaxington

Theses and Dissertations

Nearly one third of the Air Force acquisition system’s large programs are over cost and half are over budget; performance must improve. This research applies a systems perspective to this challenge and frames the acquisition system as a complex system of systems. It is a system composed of people in multiple organizations; organizations interacting with one another to develop, acquire and sustain weapon programs. The system’s performance is an emergent behavior of its components (people), structure and processes. Communication networks are a view of a system’s structure, revealing the flows and interactions between components (people) as the system accomplishes its …


The Impact Of Changing The Size Of Aircraft Radar Displays On Visual Search In The Cockpit, Justin R. Marsh Mar 2020

The Impact Of Changing The Size Of Aircraft Radar Displays On Visual Search In The Cockpit, Justin R. Marsh

Theses and Dissertations

Advances in sensor technology have enabled our fighter aircraft to find, fix, track, target, engage (F2T2E) at greater distances, providing the operator with more data within the battlefield. Modern aircraft are designed with larger displays while our legacy aircraft are being retrofitted with larger cockpit displays to enable display of the increased data. While this modification has been shown to enable improvements in human performance of many cockpit tasks, this effect is often not measured nor fully understood at a more generalizable level. This research outlines an approach to comparing human performance across two display sizes in future F-16 cockpits. …


A Comparison Of Sbir Investment Methods: Afwerx Vs Legacy, Evan A. Gist Mar 2020

A Comparison Of Sbir Investment Methods: Afwerx Vs Legacy, Evan A. Gist

Theses and Dissertations

The AFWERX Open Topic (AOT) program uses funding from the United States Air Force’s (USAF) Small Business Innovation and Research (SBIR) budget to adapt commercial technology to USAF needs. The AOT approach to small business investment is markedly different from that of legacy SBIR investment methods. This research is a comparison of processes and outcomes for AOT and legacy SBIR. The first axis of comparison is on commercialization rates. Applying a legacy definition of commercialization on a sample of AOT contracts, we found AOT’s commercialization to be 37% (compared to an 8.8% for legacy SBIR). We caveat this finding by …


The Effects Of Funding Gaps On Depot Maintenance Hours, Carlo S. D'Amato Mar 2020

The Effects Of Funding Gaps On Depot Maintenance Hours, Carlo S. D'Amato

Theses and Dissertations

The relationship between expenditures and readiness level is a topic of interest to military senior leaders, defense resource planners, and the American taxpayer alike. Senior leaders within the Air Force (AF) justify increased defense budgets by pointing to the potential adverse effects that decreased funding could have on military readiness. Resource planners within the AF are then tasked with the responsibility of ensuring that budgets are allocated most effectively to maximize the AF's ability to project airpower across a variety of contingency operations. This thesis investigates the relationship between budgets and readiness by examining the relationship between depot level funding …


Recognizing Potential Cyberspace Warriors Through The Use Of Suspicion Propensity Index, Meghan G. Strang Mar 2020

Recognizing Potential Cyberspace Warriors Through The Use Of Suspicion Propensity Index, Meghan G. Strang

Theses and Dissertations

The Air Force currently suffers from excessively high attrition rates in the cyberspace career. The field is currently aiming to develop an entrance examination for the career, striving to improve personnel selection and decrease these high attrition rates. The attribute of suspicion is a key focus of the preliminary examination development, theorizing that it is a potential indicator present among competent cyber operators. This research makes use of the Suspicion Propensity Index (SPI), a reliable measure of one’s tendency to be suspicious, along with the highly cited Mayer’s trust questionnaire in order to compare the attributes that appear in successful …


A Study Of Onboarding And Turnover Mediating Variables In U.S. Air Force Officers, Brett S. Bowers Sep 2019

A Study Of Onboarding And Turnover Mediating Variables In U.S. Air Force Officers, Brett S. Bowers

Theses and Dissertations

Employee retention, while always a concern in the workplace, has become a greater challenge for organizations in recent years. Today’s working class has displayed a propensity to change jobs more rapidly than previous generations, exacerbating not only turnover rates but also the costs associated with them (Frankel, 2016). This challenge is especially relevant to the United States Air Force, which has experienced difficulty retaining young officers in recent years. The problems resulting from this voluntary turnover are exceedingly impactful to the military command structure, as senior leaders must work their way up from the lowest ranks. As such, the Air …


Operational Decision Making Under Uncertainty: Inferential, Sequential, And Adversarial Approaches, Andrew J. Keith Aug 2019

Operational Decision Making Under Uncertainty: Inferential, Sequential, And Adversarial Approaches, Andrew J. Keith

Theses and Dissertations

Modern security threats are characterized by a stochastic, dynamic, partially observable, and ambiguous operational environment. This dissertation addresses such complex security threats using operations research techniques for decision making under uncertainty in operations planning, analysis, and assessment. First, this research develops a new method for robust queue inference with partially observable, stochastic arrival and departure times, motivated by cybersecurity and terrorism applications. In the dynamic setting, this work develops a new variant of Markov decision processes and an algorithm for robust information collection in dynamic, partially observable and ambiguous environments, with an application to a cybersecurity detection problem. In the …


Evaluation Of Rsaf Airworthiness And Applicability, Majed M. Altowairqi Sep 2018

Evaluation Of Rsaf Airworthiness And Applicability, Majed M. Altowairqi

Theses and Dissertations

This research focuses on evaluation of Royal Saudi Air Force (RSAF) airworthiness processes and their applicability. The current RSAF airworthiness process is in accordance with internationally recognized best practice in the area of military aviation, this is achieved by benchmarking against European Aviation Safety Agency (EASA) and International Organization for Standardization (ISO) standards. Airworthiness policy for the RSAF is developed on the basis that it will be as civil as possible and as military as necessary. For the purpose of this research, the current RSAF airworthiness process will be benchmarked against the United States Air Force (USAF) airworthiness process. That …


Methods To Support The Project Selection Problem With Non-Linear Portfolio Objectives, Time Sensitive Objectives, Time Sensitive Resource Constraints, And Modeling Inadequacies, Neil C. Ranly Sep 2018

Methods To Support The Project Selection Problem With Non-Linear Portfolio Objectives, Time Sensitive Objectives, Time Sensitive Resource Constraints, And Modeling Inadequacies, Neil C. Ranly

Theses and Dissertations

The United States Air Force relies upon information production activities to gain insight regarding uncertainties affecting important system configuration and in-mission task execution decisions. Constrained resources that prevent the fulfillment of every information production request, multiple information requestors holding different temporal-sensitive objectives, non-constant marginal value preferences, and information-product aging factors that affect the value-of-information complicate the management of these activities. This dissertation reviews project selection research related to these issues and presents novel methods to address these complications. Quantitative experimentation results demonstrate these methods’ significance.


Flightline Heroics And The Façade Of A Healthy Common Support Equipment Fleet, Benjamin D. Bobic Mar 2018

Flightline Heroics And The Façade Of A Healthy Common Support Equipment Fleet, Benjamin D. Bobic

Theses and Dissertations

Access to serviceable support equipment enables aircraft maintenance crews the ability to efficiently keep assigned aircraft safe and mission capable. Current Air Force policy does not require formal management and enterprise fleet health reporting of serialized support equipment. As such, articulating funding requirements to replace equipment has been a challenge for equipment managers. To better articulate support equipment requirements, equipment managers need quantifiable support equipment data. A previous study examined the relationship between aircraft availability and support equipment availability. While finding no significant correlation, the author identifies the practices of "Frankensteining" and "Beg-Borrow-Steal" as possible reasons for the absence of …


Evaluating Process Improvement Courses Of Action Through Modeling And Simulation, Joseph R. Owens Sep 2017

Evaluating Process Improvement Courses Of Action Through Modeling And Simulation, Joseph R. Owens

Theses and Dissertations

Quantifying an expected improvement when considering moderate-complexity changes to a process is time consuming and has potential to overlook stochastic effects. By modeling a process as a Numerical Design Structure Matrix (NDSM), simulating the proposed changes, and evaluating performance, quantification can be rapidly accomplished to understand stochastic effects. This thesis explores a method to evaluate complex process changes within Six Sigma DMAIC process improvement to identify the most desirable outcome amongst several improvement options. A tool to perform the modeling and evaluation is developed. This process evaluation tool is verified for functionality, then is demonstrated against generic processes, a case …


2018 Military Retirement Options: An Expected Net Present Value Decision Analysis Model, Bret N. Witham Mar 2017

2018 Military Retirement Options: An Expected Net Present Value Decision Analysis Model, Bret N. Witham

Theses and Dissertations

The 2016 NDAA authorized changes to the military retirement system transitioning from the legacy High-3 defined benefit annuity to the new Blended Retirement System (BRS). In exchange for a reduced defined benefit annuity, the BRS incorporates automatic and matching contributions to the member’s Thrift Savings Plan and a continuation payment offered at 12 years of service. In 2018,service members with less than 12 years of service will make an irrevocable decision between the two retirement systems. This research effort addresses the problem by developing a decision analysis model incorporating up to 27 different input variables. Service members can use the …


Applying Lean To The Ac-130 Maintenance Process For The Royal Saudi Air Force, Fisal A. Alzahrani Sep 2016

Applying Lean To The Ac-130 Maintenance Process For The Royal Saudi Air Force, Fisal A. Alzahrani

Theses and Dissertations

The ideas expressed in this research come from the researchers experiences working in the AC-130 maintenance squadron in the Royal Saudi Air Force. The AC-130 maintenance process is not currently being used as effectively as it could be to make AC-130 fully mission capable. That can be done by improving communication, reducing distances needed to move or transport anything during the maintenance process and by efficient use of the available qualified workforces, tools and equipment. Consideration is given to applying an existing management technique to the Royal Saudi Air Forces AC-130 Maintenance Squadrons. The selected technique is the Lean management …


Unmanned Aerial Vehicle (Uav) Operators’ Workload Reduction: The Effect Of 3d Audio On Operators’ Workload And Performance During Multi-Aircraft Control, Sungbin Kim Mar 2016

Unmanned Aerial Vehicle (Uav) Operators’ Workload Reduction: The Effect Of 3d Audio On Operators’ Workload And Performance During Multi-Aircraft Control, Sungbin Kim

Theses and Dissertations

The importance and number of Unmanned Aerial Vehicle (UAV) operations are rapidly growing in both military and civilian applications. This growth has produced significant manpower issues, producing a desire that multiple aircraft are controlled by a single operator as opposed to the current model where one aircraft may require multiple operators. A potential issue is the need for an operator to monitor radio traffic for the call signs of multi-aircraft. An investigation of the use of 3D sound was undertaken to investigate whether an automatic parser, which preselected the spatial location of relevant versus irrelevant call signs, could aid UAV …


Analysis Of Inpatient Hospital Staff Mental Workload By Means Of Discrete-Event Simulation, Erich W. Maxheimer Mar 2016

Analysis Of Inpatient Hospital Staff Mental Workload By Means Of Discrete-Event Simulation, Erich W. Maxheimer

Theses and Dissertations

Many process improvement tools have been applied to the healthcare industry to improve safety and efficiency. However, nearly all of these tools have neglected to explicitly quantify mental workload of healthcare providers despite the consensus that it is related to human performance. This research uses the Improved Performance Research Integration Tool (IMPRINT), a discrete-event simulation (DES), to quantify mental workload. Specifically, this research examines staff members in an inpatient unit at the Wright-Patterson Medical Center to detect workload differences between staff, identify trends which lead to high workload demands, evaluate the influence of patient load on mental workload, and test …


Determining The Degree Of The Routinization Of Additive Manufacturing In The Air Logistics Complexes, Candis A. Woods Mar 2016

Determining The Degree Of The Routinization Of Additive Manufacturing In The Air Logistics Complexes, Candis A. Woods

Theses and Dissertations

Fiscal constraints have affected the USAF’s spending and sustainment of weapons systems that are being utilized beyond their programmed life cycle; therefore, it is imperative that processes be given the critical eye for improvement, innovative approaches, and/or best practice implementation. The AFSC, part of the AFMC, has embarked on a groundbreaking effort to transform operations and leverage industry best practices, while maintaining focus on warfighter support to create “The AFSC Way.” The AFSC Way is based on a shared leadership model that emphasizes speed, safety, and quality, which gives way to innovative ideas and new technologies in order to achieve …


Civil Engineer Company Grade Officer Training Needs Analysis For Contingency Operations, Brian S. Greszler Mar 2016

Civil Engineer Company Grade Officer Training Needs Analysis For Contingency Operations, Brian S. Greszler

Theses and Dissertations

In terms of active duty personnel, the USAF is the smallest it has ever been since its creation in 1947. With fewer personnel to accomplish essential tasks, the training of Airmen is more important than ever. Outdated and irrelevant training can lead to gaps in the knowledge of trainees. The purpose of this research was to analyze the training needs of Civil Engineer (CE) Company Grade Officers (CGOs) in the contingency environment. This was done by first conducting a Job Analysis (JA). The JA resulted in a list of 36 critical tasks and 58 important Knowledge, Skills, and Abilities (KSAs). …


United States Air Force Officer Manpower Planning Problem Via Approximate Dynamic Programming, Amelia E. Bradshaw Mar 2016

United States Air Force Officer Manpower Planning Problem Via Approximate Dynamic Programming, Amelia E. Bradshaw

Theses and Dissertations

The United States Air Force (USAF) is concerned with managing its officer corps to ensure sufficient personnel for mission readiness. Manpower planning for the USAF is a complex process which requires making decisions about accessions. Uncertainty about officer retention complicates such decisions. We formulate a Markov decision process model of the Air Force officer manpower planning problem (AFO-MPP) and utilize a least squares approximate policy iteration algorithm as an approximate dynamic programming (ADP) technique to attain solutions. Computational experiments are conducted on two AFO-MPP instances to compare the performance of the policy determined with the ADP algorithm to a benchmark …


Pragmatic Divestment Of Kc-135 Navigators In The Special Operations Air Refueling Mission, Andrew P. Nation Mar 2015

Pragmatic Divestment Of Kc-135 Navigators In The Special Operations Air Refueling Mission, Andrew P. Nation

Theses and Dissertations

In the late 1990s, the Air Force eliminated over 200 KC-135 navigators, leaving 50 remaining for the aircraft's most complex Special Operations Air Refueling (SOAR) mission. As the Air Force unveils the KC-46 Pegasus, this mission will continue but without a position for the navigator. Instead, navigators will undergo divestment as the SOAR mission transfers to the KC-46. Current plans indicate navigators will not only remain as the KC-46 arrives, but inbound navigators will continue arriving until 2018. This thesis applies the Delphi method, a process eliciting analysis anonymously from a panel of experts, in order to examine the elements …


A Change Management Approach To Enhance Facility Maintenance Programs, Stanton P. Brown Mar 2014

A Change Management Approach To Enhance Facility Maintenance Programs, Stanton P. Brown

Theses and Dissertations

A recent study assigned a grade of D+ on the nation's public infrastructure. Because of this poor asset condition, many organizations tend to respond to maintenance in a reactive mode; however, relying on corrective maintenance leads to increased maintenance costs due to unplanned downtime, increased labor costs, and inefficient use of personnel. To address this situation, asset management (AM) principles should be employed to transition organizations towards a proactive maintenance program. Unfortunately, it has been shown that two-thirds of the organizations failed to implement general change efforts. Therefore, an organizational change management framework should be followed to implement a change …


Vehicle Minimization For The Multimodal Pickup And Delivery Problem With Time Windows, Benjamin A . Clapp Mar 2013

Vehicle Minimization For The Multimodal Pickup And Delivery Problem With Time Windows, Benjamin A . Clapp

Theses and Dissertations

The algorithm proposed here is used for heuristic solutions for the Multimodal Multiple Vehicle Routing Problem with Unloading Capacity, Pickup and Dropoff, and Time Windows, solved so as to minimize the number of vehicles used, subject to varying objective function values for each vehicle. The MVRP is simplified and split into a routing problem and a scheduling problem. The routing problem is addressed by Dijkstra's Algorithm. This generates a new network for the second stage of the algorithm. It is assumed that the shortest path is the correct path to use, and shipments each travel unimodally. The scheduling problem is …


Investigation Into Risk And Uncertainty: Identifying Coefficient Of Variation Benchmarks For Air Force Acat I Programs, Shaun T. Carney Mar 2013

Investigation Into Risk And Uncertainty: Identifying Coefficient Of Variation Benchmarks For Air Force Acat I Programs, Shaun T. Carney

Theses and Dissertations

Previous DoD cost growth studies found typical cost growth in defense acquisitions is around forty-six to sixty percent of the original estimate. The research in this study addresses the identification of risk and uncertainty benchmarks by providing decision makers with coefficient of variation ranges for cost estimates. The study recommends coefficient of variation (CV) ranges for Air Force Acquisition programs, determines if different CV ranges should be used based on platform type, and determines if CV decreases over the course of the program's acquisition lifecycle. The analysis found that the Air Force should enhance the CV review process to ensure …