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Articles 181 - 210 of 247
Full-Text Articles in Systems Engineering
Leading Indicator Analysis For High Speed Sled Test Programs, Laurie C. Knorr
Leading Indicator Analysis For High Speed Sled Test Programs, Laurie C. Knorr
Theses and Dissertations
Leading Indicators (LI) were introduced to the Systems Engineering (SE) community in 2005. These measures are used to evaluate the effectiveness of how a specific work activity is applied on a project in a manner that provides information about impacts that are likely to affect the system performance. The LIs are designed to give a project manager/systems engineer insight into where their development project is heading and a chance to implement corrective actions early. This research strives to apply LIs to the testing community, specifically high speed sled testing, to improve the testing process and, in turn, improve the quality …
Discrete Event Simulation Of Distributed Team Communication Architecture, Travis J. Pond
Discrete Event Simulation Of Distributed Team Communication Architecture, Travis J. Pond
Theses and Dissertations
As the United States Department of Defense continues to increase the number of Remotely Piloted Aircraft (RPA) operations overseas, improved Human Systems Integration becomes increasingly important. RPA systems rely heavily on distributed team communications determined by systems architecture. Two studies examine the effects of systems architecture on operator workload of US Air Force MQ-1/9 operators. The first study ascertains the effects of communication modality changes on mental workload using the Improved Research Integration Pro (IMPRINT) software tool to estimate pilot workload. Allocation of communication between modalities minimizes workload. The second study uses IMPRINT to model Mission Intelligence Controllers (MICs) and …
An Enhanced Fuselage Ultrasound Inspection Approach For Ishm Purposes, Francisco Ospina
An Enhanced Fuselage Ultrasound Inspection Approach For Ishm Purposes, Francisco Ospina
Theses and Dissertations
This effort constitutes a systems engineering approach in which the materials science, ultrasound structural health monitoring, flight and maintenance operations, and relevant aeronautical policies and programs are involved to explore the evolution and characterization of structural cracks in aircraft fuselage structures in which the loads are varying. During flight, an aircraft fuselage skin and structure are subjected to varied cyclic loads, which can cause embedded cracks and other damage features to change their characteristics due to loading effects. The current research is based in the application of finite element modeling techniques using COMSOL and PZFLEX software to characterize the behavior …
A Method For Measuring Programmatic Dependency And Interdependency Between Dod Acquisition Programs, Matthew B. Christensen
A Method For Measuring Programmatic Dependency And Interdependency Between Dod Acquisition Programs, Matthew B. Christensen
Theses and Dissertations
There is currently no accepted method for quantitative measurement of acquisition program interdependency. While some methods exist for measuring dependency or interdependency at the component or system level, these methods do not translate well to program interdependency measurement. The objective of this thesis is to provide a model for measuring acquisition program interdependency accurately and quantitatively. The model presented in this thesis uses four Interdependency Factors to identify dependency relationships between programs. Specific Interdependency Levels are then used to measure the strengths of those dependencies. The model also accounts for measurement of dependencies upon programs that are not directly connected, …
Rapid Development: A Content Analysis Comparison Of Literature And Purposive Sampling Of Afrl Rapid Reaction Projects, Andrew R. Smith
Rapid Development: A Content Analysis Comparison Of Literature And Purposive Sampling Of Afrl Rapid Reaction Projects, Andrew R. Smith
Theses and Dissertations
In the current environment of military operations requesting faster delivery schedules to counter insurgent tactics, the engineering team often searches for how to quickly deliver the 80% solution, typically in 6-12 months. These are labeled rapid development projects. A content analysis of best practices in commercial product development literature, where time to market is often a driving factor, was accomplished showing varying emphasis of systems engineering technical and technical management processes. Technical Planning, Stakeholders Requirements Development, and Architecture Design were identified as important processes. This analysis confirms preconceived notions of plan upfront and early by emphasizing the SE processes of …
Enterprise Requirements And Acquisition Model, David A. Leach, Chad T. Searle
Enterprise Requirements And Acquisition Model, David A. Leach, Chad T. Searle
Theses and Dissertations
In support of senior leadership emphasis on improving early systems engineering and analysis, the Enterprise Requirements and Acquisition Model (ERAM) is a quantitative discrete-event process simulation model that accounts for activities from the identification of a desired space capability early in the JCIDS process through Milestone C of the acquisition system resulting in a probabilistic schedule distribution for a given concept. This model of the DoD's space capability development process will provide valuable decision making information for Concept Characterization and Technical Descriptions referenced during Analysis of Alternatives. The research focused on identifying activities, assigning historical triangular distributions and probabilities at …
A Primary Care Workload Production Model For Estimating Relative Value Unit Output, Rachel G. Murphy
A Primary Care Workload Production Model For Estimating Relative Value Unit Output, Rachel G. Murphy
Theses and Dissertations
Health care costs have grown to unsustainable levels nationally and within the Department of Defense. Military health care costs have historically been difficult to isolate, causing budget cuts to be the vehicle for cost control. Maximum efficiency, therefore, is the goal in order to show improvement. With the Air Force’s new preventive health plan, they aim to drive a long-term posture for cost reduction through prevention. This research effort aimed to develop a tool to assist in future efforts to understand and improve efficiency in workload output, and whether a relationship exists between patient workload demand and the per-encounter variables …
Application And Validation Of Concept Maturity Assessment Framework, Mathews C. Scharch, Jeremy J. Homan
Application And Validation Of Concept Maturity Assessment Framework, Mathews C. Scharch, Jeremy J. Homan
Theses and Dissertations
Far too often decision makers select concepts based on insufficient data, resulting in projects that are over-budget, over-schedule, and not what the customer wants. Research efforts have proposed a stage-gated concept maturity framework as a tool to assess and increase the maturity of concepts. This research uses multiple validation techniques to demonstrate the value this framework can provide. Interviews with acquisition professionals capture qualitative and quantitative data on the utility of the elements of the framework and the acquisition process. This research also applies the framework to a current acquisition program to determine if it can be broadly applied for …
Extending The Strategy Based Risk Model Using The Delphi Method: An Application To The Validation Process For Research And Developmental (R&D) Satellites, Amanda J. Langenbrunner, Mary R. Trautwein
Extending The Strategy Based Risk Model Using The Delphi Method: An Application To The Validation Process For Research And Developmental (R&D) Satellites, Amanda J. Langenbrunner, Mary R. Trautwein
Theses and Dissertations
The validation between a research and developmental satellite and its ground system is critical to ensuring the success on-orbit. However, the exact process for completing validation is not documented, frequently underfunded, and accomplished ad hoc. This leads to debate regarding maintenance of budget and schedule, while ensuring on-orbit success. This thesis examines readiness and on-orbit activities within the U.S. Air Force Space Development and Test Wing's Research Development Test and Evaluation Support Complex. Combining historical data with the consultation of subject matter experts, a validation process was defined. Risks associated with this process were then analyzed using the Strategy Based …
Analyzing Systems Integration Best Practices And Assessment In Dod Space Systems Acquisition, Douglas R. Dillon, Enriqueta M. Styres
Analyzing Systems Integration Best Practices And Assessment In Dod Space Systems Acquisition, Douglas R. Dillon, Enriqueta M. Styres
Theses and Dissertations
Senior leadership of the Air Force's Space and Missile Center suggested an investigation of systems integration within the space acquisition community in the fall of 2008. This thesis performs that investigation. A review concluded that while Systems Integration (SI) is extensively discussed as an area deserving considerable attention in the Systems Engineering literature, definitions are weak and methods and tools non-existent. Known SI activities are not being traced and assessed for adequacy throughout system development. Employing the Space System Acquisition Lifecycle Framework as the environment for this research, a method of characterizing and tracing SI throughout a program‘s lifecycle by …
Changes In Structural Health Monitoring System Capability Due To Aircraft Environmental Factors, Jeffrey D. Kuhn
Changes In Structural Health Monitoring System Capability Due To Aircraft Environmental Factors, Jeffrey D. Kuhn
Theses and Dissertations
Structural Health Monitoring (SHM) promises to decrease the maintenance cost and increase the availability of aging aircraft fleets by fundamentally changing the way structural inspections are performed. But this promise can only be realized through the consistent and predictable performance of a SHM system throughout the entire remaining life of an aircraft. In a sensor-based SHM system, sensor signal changes are analyzed and interpreted to identify structural flaws. But aircraft environmental factors such as temperature fluctuations, cyclic strain and exposure to various aircraft fluids also have the potential to change SHM sensor signals, raising questions about long term SHM system …
Application Of Reliability And Linear Regression To Enterprise Architecture In Support Of The Us Air Force's Capability Review And Risk Assessment, Peter C. Mastro, Richard L. Orcutt
Application Of Reliability And Linear Regression To Enterprise Architecture In Support Of The Us Air Force's Capability Review And Risk Assessment, Peter C. Mastro, Richard L. Orcutt
Theses and Dissertations
This research explored the use of modeling and enterprise architecture in the analysis of Air Force Capabilities. The Air Force accomplishes this through the Capability Review and Risk Assessment (CRRA). The CRRA is currently performed by building architectures which contain Process Sequence Models (PSMs). PSMs are scored by Subject Matter Experts to determine the probability of successfully completing the mission they model and ultimately to determine the risk associated to Air Force capabilities. Two findings were identified. The first is that creating additional architectural viewpoints, some of which are currently being proposed for version 2.0 of the DoD Architecture Framework, …
A Tailored Systems Engineering Framework For Science And Technology Projects, Stephen M. Behm, J. Bradford Pitzer, Jane F. White
A Tailored Systems Engineering Framework For Science And Technology Projects, Stephen M. Behm, J. Bradford Pitzer, Jane F. White
Theses and Dissertations
As government and industry becomes subject to a wider range of technology initiatives, science and technology (S&T) research project leadership recognizes the need to incorporate more systems engineering (SE) rigor into their projects. The objective of this research is to develop a tailorable systems engineering framework for S&T project planning, execution, assessment and transition. The key deliverable is an Excel-based tool instantiating the SE framework for a wide range of S&T projects in technology development organizations. It includes a report with tailored methods based on programmatic discriminants.
To develop this framework, a comprehensive understanding of SE principles is applied to …
Value-Driven Enterprise Architecture Score: Evaluation Applied To Joint Force Protection Future State Design, Larry D. Cotton, Gary A. Haase
Value-Driven Enterprise Architecture Score: Evaluation Applied To Joint Force Protection Future State Design, Larry D. Cotton, Gary A. Haase
Theses and Dissertations
This research presents a methodology to evaluate the quality of a system's architecture using principles drawn from Value-Focused Thinking (VFT) and resulting in a Value-Driven Enterprise Architecture Score (VDEA-Score). This is an overall numerical architecture quality score useful to a system's management team to identify the advantages and disadvantages of a system design and associated architecture documentation or to track its quality across discrete evaluation epochs. This effort determined which aspects of the architecture are most valuable to the stakeholder in the areas of (1) the system effectiveness values (quality of the instantiated system being represented and its ability to …
The Hybrid Counterinsurgency Strategy: System Dynamics Employed To Develop A Behavioral Model Of Joint Strategy, Ferdinand Maldonado
The Hybrid Counterinsurgency Strategy: System Dynamics Employed To Develop A Behavioral Model Of Joint Strategy, Ferdinand Maldonado
Theses and Dissertations
Since the recent focus on the Global War on Terror, both military and civilian theorists have begun to “relearn” the intricacies of counterinsurgency warfare. We face difficult challenges when confronting non-state actors that tend to attack in the time between conventional battles and the establishment of stable governments. This research compares and contrasts current counterinsurgency strategies (Hearts and Minds and Cost Benefit Theory) by applying System Dynamics to provide insight into the influences and emergent behavior patterns of counterinsurgency systems. The information gained from the development of the models and from their simulation behaviors is used to construct a System …
Developing A Decision Model For Joint Improvised Explosive Device Defeat Organization (Jieddo) Proposal Selection, Lyle M. Dawley, Lenore A. Marentee, Alice Marie Long
Developing A Decision Model For Joint Improvised Explosive Device Defeat Organization (Jieddo) Proposal Selection, Lyle M. Dawley, Lenore A. Marentee, Alice Marie Long
Theses and Dissertations
This research uses decision analysis to develop a structured, repeatable and most importantly defensible decision model for the evaluation of proposed IED defeat solutions submitted to the Joint IED Defeat Organization (JIEDDO). Additive value models using Value-Focused Thinking (VFT) and the Analytic Hierarchy Process (AHP) are examined as possible methodologies. VFT is determined to be the "best fit" for JIEDDO's decision situation in which proposals are submitted continuously and must be scored independently of previous proposals. VFT is first used to determine desirable qualities in IED defeat options, and then to generate a hierarchal value model to evaluate these qualities …
Forecasting Flying Hour Costs Of The B-1, B-2, And B-52 Bomber Aircraft, Stefanie L. Van Dyk
Forecasting Flying Hour Costs Of The B-1, B-2, And B-52 Bomber Aircraft, Stefanie L. Van Dyk
Theses and Dissertations
This thesis both evaluates, and presents improvements to, the current method of forecasting flying costs of Air Force aircraft. It uses depot level repairable (DLR) and consumable (CONS) data for the Air Force's bomber platforms: B-1B, B-2, and B-52H. The current forecasting method assumes a proportional relationship between costs and flying hours such that 1) when no hours are flown costs are zero, and 2) a 1% increase in flying hours will increase costs by 1%. The findings of this research indicate that applying log-linear ordinary least squares regression techniques may be an improved fit of flying cost data over …
Operationally Responsive Space (Ors): An Architecture And Enterprise Model For Adaptive Integration, Test And Logistics, Jeff A. Alexander, Martha Charles-Vickers, Talbot L. Smith, Michael L. Vickers
Operationally Responsive Space (Ors): An Architecture And Enterprise Model For Adaptive Integration, Test And Logistics, Jeff A. Alexander, Martha Charles-Vickers, Talbot L. Smith, Michael L. Vickers
Theses and Dissertations
The capability to rapidly deploy tactical satellites to meet a Joint Force Commander's immediate battlespace requirements is a well-documented joint capability need. Key U.S. strategic documentation cites the need for the capability to maintain persistent surveillance or an "unblinking eye" over battlespace and to rapidly reconstitute critical space capabilities to preserve situational awareness. The warfighter requires a tactical space-based deployment capability which employs a request to launch and operational deployment window of 90 to 120 days. This master's thesis executed two (2) major areas of work: apply, and reinforce the Operationally Responsive Space (ORS) mission tasks using the Joint Capabilities …
A System Dynamic Model Of Leader Emergence, Paul S. Wever
A System Dynamic Model Of Leader Emergence, Paul S. Wever
Theses and Dissertations
The purpose of this thesis is to develop a system dynamics model of leader emergence. Longitudinal social network and personality data were collected in a class of enlisted military professionals attending a 6-week leadership development course. Findings support known relationships in existing leadership research. The thesis demonstrates the applicability of system dynamics toward the complex social phenomena of leader emergence.
A Decision Tool To Evaluate Budgeting Methodologies For Estimating Facility Recapitalization Requirements, Krista M. Hickman
A Decision Tool To Evaluate Budgeting Methodologies For Estimating Facility Recapitalization Requirements, Krista M. Hickman
Theses and Dissertations
The purpose of this research was to develop a decision tool to assist in the evaluation of facility recapitalization budget estimation models to determine which model was best suited for a particular organization. Specifically, this thesis sought to answer an overarching research question addressing the importance of recapitalization and the best method to estimate the facility recapitalization budget using the Department of Defense (DoD) as the subject of the research. A comprehensive literature review revealed ten existing recapitalization model alternatives to consider for implementation. The methodology used to develop a decision tool was based on the Value Focused Thinking (VFT) …
The Impact Of Operations Tempo (Optempo) On Intentions To Depart The Military. Does The Increase Of Optempo Cause Action, Nathan P. Olsen
The Impact Of Operations Tempo (Optempo) On Intentions To Depart The Military. Does The Increase Of Optempo Cause Action, Nathan P. Olsen
Theses and Dissertations
Recent information in the field of Operations Tempo (OPTEMPO) has resulted in conflicting information on its effect on turnover intentions. This study evaluated the August 2004 Status of Forces Survey to determine if the sample demonstrated OPTEMPO had a curvilinear effect on turnover intentions when accounting for the moderators job satisfaction and organizational commitment while controlling for rank and gender. Linear regressions were used to determine if the relationship between OPTEMPO and turnover intentions were significant. When accounting for job satisfaction and organizational commitment the relationship between OPTEMPO and turnover intentions is not significant, this indicated that OPTEMPO and turnover …
Information Management Principles Applied To The Ballistic Missile Defense System, John M. Koehler Ii
Information Management Principles Applied To The Ballistic Missile Defense System, John M. Koehler Ii
Theses and Dissertations
Information systems (IS) have evolved over the last 50 plus years from individual components with single functionality to grand architectures that integrate multiple individual business functions into global organizational enterprises. Similarly several military systems with the single mission of missile defense have evolved in service stovepipes, and are now being integrated into a national and global missile defense architecture. The Missile Defense Agency (MDA) is currently tasked with developing an integrated Ballistic Missile Defense System (BMDS) capable of defending against all ranges of ballistic missiles in all phases of flight in defense of the homeland, our deployed forces, and our …
Selecting Electricity Generation Sources In Remote Locations, Kelly E. Kwan
Selecting Electricity Generation Sources In Remote Locations, Kelly E. Kwan
Theses and Dissertations
The purpose of this research was to investigate the impact of using a decision analysis technique for the selection of an electrical generation system for remote locations. Specifically, this thesis sought to answer five research questions addressing the types of energy sources used in remote locations, the decision-making processes used to identify these sources, the types of constraints incorporated in such a process, other valued factors, and their level of importance in relation to each other. The research questions were answered through a comprehensive literature review and the 10-Step Value-Focused Thinking Process on a specific case study in the National …
Towards The Development Of A Defensive Cyber Damage And Mission Impact Methodology, Larry W. Fortson Jr.
Towards The Development Of A Defensive Cyber Damage And Mission Impact Methodology, Larry W. Fortson Jr.
Theses and Dissertations
The purpose of this research is to establish a conceptual methodological framework that will facilitate effective cyber damage and mission impact assessment and reporting following a cyber-based information incidents. Joint and service guidance requires mission impact reporting, but current efforts to implement such reporting have proven ineffective. This research seeks to understand the impediments existing in the current implementation and to propose an improved methodology. The research employed a hybrid historical analysis and case study methodology for data collection through extensive literature review, examination of existing case study research and interviews with Air Force members and civilian personnel employed as …
Recommendations For A Standardized Program Management Office (Pmo) Time Compliance Network Order (Tcno) Patching Process, Michael Czumak Iii
Recommendations For A Standardized Program Management Office (Pmo) Time Compliance Network Order (Tcno) Patching Process, Michael Czumak Iii
Theses and Dissertations
Network security is a paramount concern for organizations utilizing computer technology, and the Air Force is no exception. Network software vulnerability patching is a critical determinant of network security. The Air Force deploys these patches as Time Compliance Network Orders (TCNOs), which together with associated processes and enforced timelines ensure network compliance. While the majority of the network assets affected by this process are Air Force owned and operated, a large number are maintained by external entities known as Program Management Offices (PMOs). Although these externally controlled systems provide a service to the Air Force and reside on its network, …
Graph Theoretical Analysis Of Network Centric Operations Using Multi-Layer Models, Ann Wong-Jiru
Graph Theoretical Analysis Of Network Centric Operations Using Multi-Layer Models, Ann Wong-Jiru
Theses and Dissertations
As the Department of Defense continues its transformations to a network centric force, evaluating DoD's progression towards net-centricity remains a challenge. This research proposes to extend the Network Centric Operation Common Framework Version 2.0 (draft) with the metrics based in graph theory and, specifically addresses, among other metrics, the measurement of a net-centric force's mission effectiveness. The research incorporates the importance of understanding network topology for evaluating an environment for net-centricity and using network characteristics to help commanders assess the effects of network changes on mission effectiveness. The multi-layered model of Network Centric Operations and interlayer mapping are introduced to …
Technology Transfer: A Qualitative Analysis Of Air Force Office Of Research And Technology Applications, David C. Trexler
Technology Transfer: A Qualitative Analysis Of Air Force Office Of Research And Technology Applications, David C. Trexler
Theses and Dissertations
Everyday within United States Air Forces’ research laboratories there are hundreds of scientists and engineers whose research and development activities contribute to the advancement of science and technology for mankind. The opportunities for successful technology transfer within these research activities are unbounded. This thesis examines the Air Force Office of Research and Technology Applications (ORTA’s) involvement with technology transfer, the complexities they face, the importance of their position, and what best practices ORTAs use to facilitate technology transfer. Air Force concerns and initiatives are detailed to provide perspective on balancing technology transfer with mission requirements and adherence to United States …
A Graph Theoretic Analysis Of The Effects Of Organizational Structure On Employee Social Networks, John R. Hutzel
A Graph Theoretic Analysis Of The Effects Of Organizational Structure On Employee Social Networks, John R. Hutzel
Theses and Dissertations
A simulation technique was used to investigate the impacts of organizational structure on an organization's social network. By simulating personnel in an organization as vertices in a graph and the aging of the corporation as the aging of the same graph, the maturation of an organization was realized. The characteristic path length of the graph was measured after each year returning an optimistic average organizational distance. Results include the finding that, per this model, an organization's characteristic path length can drop over 50% in a 20 year period with consideration of edges of all strengths. Next a series of random …
A Systems Engineering Approach To Integrated Structural Health Monitoring For Aging Aircraft, Alan P. Albert, Efstathios Antoniou, Stephen D. Leggiero, Kimberly A. Tooman, Ramon L. Veglio
A Systems Engineering Approach To Integrated Structural Health Monitoring For Aging Aircraft, Alan P. Albert, Efstathios Antoniou, Stephen D. Leggiero, Kimberly A. Tooman, Ramon L. Veglio
Theses and Dissertations
The United States Air Force and many of its Coalition partners have extended the original service life of some of their aging aircraft due to fiscal constraints. This life extension often requires increased periodic and in-depth inspections; increasing maintenance costs and resulting in longer periods of aircraft downtime. A structural health monitoring system for aging aircraft could reduce the current inspection burden, and thus decrease costs and system downtime. This presentation describes a baseline systems engineering methodology for system definition of an aging aircraft structural health monitoring system. Analysis was performed to quantify the potential benefit a structural health monitoring …
A Comparative Usability And End-User Satisfaction Analysis Of Two Geographic Information System (Gis) Applications, Mark E. Barner
A Comparative Usability And End-User Satisfaction Analysis Of Two Geographic Information System (Gis) Applications, Mark E. Barner
Theses and Dissertations
The Air Force has recognized that organizations across Air Force installations often require geospatial information resources or maps to accomplish mission essential tasks. To provide an AF-wide approach to addressing this need, in 2001, the Headquarters Air Force Geo Integration Office formed the USAF GeoBase program. GeoBase is the name given to the Air Force's GIS program. As GeoBase has been implemented across the Air Force, there have been no mandated product standards for GIS applications. This thesis focuses on two different GIS applications being used across the CE community for the management of airfield obstructions. These two applications are …