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Articles 2911 - 2940 of 5606
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A Comparison Of The U.S. Air Force Fitness Test And Sister Services' Combat-Oriented Fitness Tests, Thomas E. Worden
A Comparison Of The U.S. Air Force Fitness Test And Sister Services' Combat-Oriented Fitness Tests, Thomas E. Worden
Theses and Dissertations
This research explores how the United States Air Force Physical Fitness Test (AFPFT) events compare to sister-services' physical fitness test events with respect to their predictability of combat capability. Multiple regression tools, non-parametric analyses, and chi2 contingency table hypothesis testing were utilized to test hypotheses about performances and determine associations between involved variables. AFPFT scores had minimal predictability (adj R2 0.2045) [but improved when raw data replaced scoring sheets, pushups have no maximum, and abdominal circumference and age are removed (adj R2 0.7703)]. Higher Body Mass Index (BMI) predicts higher combat capability (p-value 0.0208). The best two-event …
Surface Acoustic Wave Devices As Chemical Vapor Sensors, Daniel Gallagher
Surface Acoustic Wave Devices As Chemical Vapor Sensors, Daniel Gallagher
Theses and Dissertations
In order to effectively neutralize non-traditional threats to US forces and population such as improvised explosive devices (IED) and chemical, biological, radio- logical, nuclear, and explosive (CBNRE) weapons, a flexible vapor sensor platform is proposed. This work involves the design, fabrication, and testing of coated surface acoustic wave devices for vapor sensing ability. Devices were fabricated in-house using MEMS fabrication techniques, then coated with a thin layer of a Nafion polymer. The frequency response of coated devices displayed 2 MHz frequency shifts around the resonance frequency upon introduction of ethanol vapors into the nitrogen vapor stream. This indicates strong sensing …
Radar Imaging With A Network Of Digital Noise Radar Systems, Ashley L. Schmitt
Radar Imaging With A Network Of Digital Noise Radar Systems, Ashley L. Schmitt
Theses and Dissertations
Today's battlefield consists of a blend of humans and machines working together to locate and monitor the enemy. Due to the threat of terrorism, today's enemy can be anyone and they can exist anywhere even in populated cities. Monitoring human activities in an urban environment is a difficult problem due to walls, clutter, and other obstructions. This thesis focused on developing a network of digital noise radar sensors that could operate simultaneously to track humans and non-human targets inside rooms and through walls. The theory, application, and results are discussed throughout this thesis. A noise radar works by cross correlating …
Adaptive Pareto Set Estimation For Stochastic Mixed Variable Design Problems, Christopher D. Arendt
Adaptive Pareto Set Estimation For Stochastic Mixed Variable Design Problems, Christopher D. Arendt
Theses and Dissertations
Many design problems require the optimization of competing objective functions that may be too complicated to solve analytically. These problems are often modeled in a simulation environment where static input may result in dynamic (stochastic) responses to the various objective functions. System reliability, alloy composition, algorithm parameter selection, and structural design optimization are classes of problems that often exhibit such complex and stochastic properties. Since the physical testing and experimentation of new designs can be prohibitively expensive, engineers need adequate predictions concerning the viability of various designs in order to minimize wasteful testing. Presumably, an appropriate stochastic multi-objective optimizer can …
Project Scheduling To Maximize Positive Impacts Of Reconstruction Operations, Andrew D. Chaney
Project Scheduling To Maximize Positive Impacts Of Reconstruction Operations, Andrew D. Chaney
Theses and Dissertations
Since the decline of the Cold War, the risk of major conflict between powerful industrialized nations has significantly decreased. Insecurity in the twenty-first century is forecast to arise rather from the debris of imploding states. Such situations may require intervention | military or otherwise | by concerned states, and the frequency with which these interventions occur is increasing. To meet this new operational challenge, the US military must adapt its planning procedures to account for Security, Stabilization, Transition, and Reconstruction Operations (SSTRO). This research develops a project scheduling based framework for post-conflict reconstruction that prioritizes and schedules reconstruction activities in …
Using Multiple Robust Parameter Design Techniques To Improve Hyperspectral Anomaly Detection Algorithm Performance, Matthew T. Davis
Using Multiple Robust Parameter Design Techniques To Improve Hyperspectral Anomaly Detection Algorithm Performance, Matthew T. Davis
Theses and Dissertations
Detecting and identifying objects of interest is the goal of all remote sensing. New advances, specifically in hyperspectral imaging technology have provided the analyst with immense amounts of data requiring evaluation. Several filtering techniques or anomaly detection algorithms have been proposed. However, most new algorithms are insufficiently verified to be robust to the broad range of hyperspectral data being made available. One such algorithm, AutoGAD, is tested here via two separate robust parameter design techniques to determine optimal parameters for consistent performance on a range of data with large attribute variances. Additionally, the results of the two techniques are compared …
An Advanced Tabu Search Approach To Solving The Mixed Payload Airlift Load Planning Problem, Robert Larry Nance
An Advanced Tabu Search Approach To Solving The Mixed Payload Airlift Load Planning Problem, Robert Larry Nance
Theses and Dissertations
This paper presents a new tabu search based two-dimensional bin packing algorithm which produces high quality solutions to the Mixed Payload Airlift Load Planning (MPALP) problem using C-5 and C-17 aircraft. This algorithm, called Mixed Payload Airlift Load Planning Tabu Search (MPALPTS), surpasses previous research conducted in this area because, in addition to pure pallet cargo loads, MPALPTS can accommodate rolling stock cargo (i.e. tanks, trucks, HMMMVs, etc.) while still maintaining aircraft feasibility with respect to aircraft center of balance, mandatory cargo separations, aircraft floor structural limitations, etc. Furthermore, while this research is currently restricted to C-5 and C-17 aircraft, …
Exploitation Of Intra-Spectral Band Correlation For Rapid Feacture Selection And Target Identification In Hyperspectral Imagery, Michael K. Miller
Exploitation Of Intra-Spectral Band Correlation For Rapid Feacture Selection And Target Identification In Hyperspectral Imagery, Michael K. Miller
Theses and Dissertations
This research extends the work produced by Capt. Robert Johnson for detecting target pixels within hyperspectral imagery (HSI). The methodology replaces Principle Components Analysis for dimensionality reduction with a clustering algorithm which seeks to associate spectral rather than spatial dimensions. By seeking similar spectral dimensions, the assumption of no a priori knowledge of the relationship between clustered members can be eliminated and clusters are formed by seeking high correlated adjacent spectral bands. Following dimensionality reduction Independent Components Analysis (ICA) is used to perform feature extraction. Kurtosis and Potential Target Fraction are added to Maximum Component Score and Potential Target Signal …
Host-Based Multivariate Statistical Computer Operating Process Anomaly Intrusion Detection System (Paids), Glen R. Shilland
Host-Based Multivariate Statistical Computer Operating Process Anomaly Intrusion Detection System (Paids), Glen R. Shilland
Theses and Dissertations
No abstract provided.
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 …
Assessing Structural Health Monitoring Alternatives Utilizing A Value-Focused Thinking Model, Margaret A. Barker, Fatih S. Gurbuz, Jeremy A. Schroeder
Assessing Structural Health Monitoring Alternatives Utilizing A Value-Focused Thinking Model, Margaret A. Barker, Fatih S. Gurbuz, Jeremy A. Schroeder
Theses and Dissertations
Current Air Force operations are undergoing significant changes necessitated by increasing fiscal constraints, increasing aircraft age, and recent drawdown in personnel to perform maintenance, repair, and other necessary functions. In order to deal with these challenges, the Air Force must effectively improve current operations. This paper explores potential structural health monitoring (SHM) solutions to some of the challenges facing aircraft maintenance and repair operations. As with any problem, a variety of solutions exist and this paper explores the potential solutions and limitations of various options. Aircraft SHM is an intriguing concept with potential capability to revolutionize current Air Force maintenance …
Architecting Human Operator Trust In Automation To Improve System Effectiveness In Multiple Unmanned Aerial Vehicles (Uav), Eric A. Cring, Adam G. Lenfestey
Architecting Human Operator Trust In Automation To Improve System Effectiveness In Multiple Unmanned Aerial Vehicles (Uav), Eric A. Cring, Adam G. Lenfestey
Theses and Dissertations
Current Unmanned Aerial System (UAS) designs require multiple operators for each vehicle, partly due to imperfect automation matched with the complex operational environment. This study examines the effectiveness of future UAS automation by explicitly addressing the human/machine trust relationship during system architecting. A pedigreed engineering model of trust between human and machine was developed and applied to a laboratory-developed micro-UAS for Special Operations. This unprecedented investigation answered three primary questions. Can previous research be used to create a useful trust model for systems engineering? How can trust be considered explicitly within the DoD Architecture Framework? Can the utility of architecting …
Misregistration In Adaptive Optics Systems, Nathan D. Engstrom
Misregistration In Adaptive Optics Systems, Nathan D. Engstrom
Theses and Dissertations
An adaptive optics (AO) system is most effective when there is a known alignment between the wave front sensor (WFS) and the deformable mirror (DM). Misregistration is the term for the unknown alignment between the WFS and DM. Misregistration degrades system performance and can make the system unstable. An AO system uses a reconstruction matrix to transform WFS measurements into DM commands. A standard AO system uses a model reconstruction matrix that assumes perfect registration between the WFS and DM. The object of this research is to mitigate the negative effects of misregistration by using offline WFS measurements to create …
Low Probability Of Intercept Waveforms Via Intersymbol Dither Performance Under Multipath Conditions, Jonathan K. Keen
Low Probability Of Intercept Waveforms Via Intersymbol Dither Performance Under Multipath Conditions, Jonathan K. Keen
Theses and Dissertations
This thesis examines the effects of multipath interference on Low Probability of Intercept (LPI) waveforms generated using intersymbol dither. LPI waveforms are designed to be difficult for non-cooperative receivers to detect and manipulate, and have many uses in secure communications applications. In prior research, such a waveform was designed using a dither algorithm to vary the time between the transmission of data symbols in a communication system. This work showed that such a method can be used to frustrate attempts to use non-cooperative receiver algorithms to recover the data. This thesis expands on prior work by examining the effects of …
Image Processing For Multiple-Target Tracking On A Graphics Processing Unit, Michael A. Tanner
Image Processing For Multiple-Target Tracking On A Graphics Processing Unit, Michael A. Tanner
Theses and Dissertations
Multiple-target tracking (MTT) systems have been implemented on many different platforms, however these solutions are often expensive and have long development times. Such MTT implementations require custom hardware, yet offer very little flexibility with ever changing data sets and target tracking requirements. This research explores how to supplement and enhance MTT performance with an existing graphics processing unit (GPU) on a general computing platform. Typical computers are already equipped with powerful GPUs to support various games and multimedia applications. However, such GPUs are not currently being used in desktop MTT applications. This research explores if and how a GPU can …
The Modular Clock Algorithm For Blind Rendezvous, Nicholas C. Theis
The Modular Clock Algorithm For Blind Rendezvous, Nicholas C. Theis
Theses and Dissertations
This thesis examines the problem in initializing communications whereby cognitive radios need to find common spectrum with other cognitive radios, a process known as frequency rendezvous. It examines the rendezvous problem as it exists in a dynamic spectrum access cognitive network. Specifically, it addresses the problem of rendezvous in an infrastructureless environment. A new algorithm, the modular clock algorithm, is developed and analyzed as a solution for the simple rendezvous environment model, coupled with a modified version for environment models with less information. The thesis includes a taxonomy of commonly used environment models, and analysis of previous efforts to solve …
Characterizing And Detecting Unrevealed Elements Of Network Systems, James A. Leinart
Characterizing And Detecting Unrevealed Elements Of Network Systems, James A. Leinart
Theses and Dissertations
This dissertation addresses the problem of discovering and characterizing unknown elements in network systems. Klir (1985) provides a general definition of a system as “... a set of some things and a relation among the things" (p. 4). A system, where the `things', i.e. nodes, are related through links is a network system (Klir, 1985). The nodes can represent a range of entities such as machines or people (Pearl, 2001; Wasserman & Faust, 1994). Likewise, links can represent abstract relationships such as causal influence or more visible ties such as roads (Pearl, 1988, pp. 50-51; Wasserman & Faust, 1994; Winston, …
Waste Vegetable Oil As An Alternative Fuel For Diesel Vehicles, Harvey S. Gaber
Waste Vegetable Oil As An Alternative Fuel For Diesel Vehicles, Harvey S. Gaber
Theses and Dissertations
Alternative fuels have become a hot topic in the news as the cost of oil remains volatile. Questions of whether acquiring alternative fuels are worth the cost, logistics, and political implications are being asked. A possible solution may be currently thrown away by Wright Patterson Air Force Base’s (WPAFB) dining establishments in the form of Waste Vegetable Oil (WVO). This study researched the benefits and costs of pursuing the installation of a WVO to Straight Vegetable Oil fuel processing center and using the fuel to power some of the base’s diesel vehicles. A pilot program was fielded utilizing the Wright …
An Exploratory Social Network Analysis Of Military And Civilian Emergency Operation Centers Focusing On Organization Structure, Joseph D. Legradi
An Exploratory Social Network Analysis Of Military And Civilian Emergency Operation Centers Focusing On Organization Structure, Joseph D. Legradi
Theses and Dissertations
The purpose of this research was to explore how United States Air Force Emergency Operation Centers (EOC) compare to civilian EOCs with respect to their task-based social networks and decision making social networks. Multiple measures were explored to understand the networks, which included analyzing key metrics of the network such as closeness centrality and betweenness centrality, centralization of the network, and comparison of structural holes within the networks. These measures were then used to suggest improvements for the organizations to improve performance and more importantly, interoperability. The results of the study showed that in this data set there were several …
A Metagenomic Analysis Of Microbial Contamination In Aviation Fuels, Jerrod P. Mccomb
A Metagenomic Analysis Of Microbial Contamination In Aviation Fuels, Jerrod P. Mccomb
Theses and Dissertations
Microbial contamination in aviation fuel arises due to the impracticality of keeping fuel tanks sterile and the inevitable presence of water from condensation. Microbial contaminants in aviation fuels are a concern because of their potential to degrade the fuel, accelerate corrosion within the fuel tank, and threaten flight safety. This research aids in mitigating those problems by comprehensively characterizing the microbial communities affecting aviation fuels. Advances in molecular biological techniques have allowed for the identification of microorganisms which were not identified by the traditional culture-based methodologies used in previous studies. This study employed a molecular method known as 16S rDNA …
Heterogeneity Effects In Plutonium Contaminated Soil, Orlando M. Chaparro
Heterogeneity Effects In Plutonium Contaminated Soil, Orlando M. Chaparro
Theses and Dissertations
In 1960 at the McGuire Air Force Base, New Egypt, New Jersey a helium tank ruptured causing a fire to ignite a nearby nuclear tipped Boeing Michigan Aeronautical Research Center (BOMARC) missile. During the fire the weapons grade plutonium (Pu- 239, Pu-240, and Pu-241) ignited and was released into the surrounding area, due to both firefighting efforts, where high pressure water was used to put out the fire, as well as smoke that deposited plutonium as oxidized particles in the surrounding area (Cicotte, 2007). This study investigates the heterogeneity of the distributed plutonium contamination in the McGuire Air Force Base …
Probabilistic Estimation Of Rare Random Collisions In 3-Space, Timothy Holzmann
Probabilistic Estimation Of Rare Random Collisions In 3-Space, Timothy Holzmann
Theses and Dissertations
A study of risk assessment for artillery fire randomly colliding with fixed wing aircraft is presented. The research lends itself to a general study of collision models. Current models of object collisions fall under one of three categories: the historical model, the gas particle model, and the satellite model. These three vary in data requirements and mathematical representation of the impact event. The gas particle model is selected for its flexibility and robust estimation. However, current mathematical development in the literature does not include certain spatial and dynamic components necessary for a general encounter (collision) model. These are derived in …
Creating Multi Objective Value Functions From Non-Independent Values, Christopher D. Richards
Creating Multi Objective Value Functions From Non-Independent Values, Christopher D. Richards
Theses and Dissertations
Decisions are made every day and by everyone. As these decisions become more important, involve higher costs and affect a broader group of stakeholders it becomes essential to establish a more rigorous strategy than simply intuition or "going with your gut". In the past several decades, the concept of Value Focused Thinking (VFT) has gained much acclaim in assisting Decision Makers (DMs) in this very effort. By identifying and organizing what a DM values VFT is able to decompose the original problem and create a mathematical model to score and rank alternatives to be chosen. But what if the decision …
Using Agent-Based Modeling To Evaluate Uas Behaviors In A Target-Rich Environment, Joseph A. Van Kuiken
Using Agent-Based Modeling To Evaluate Uas Behaviors In A Target-Rich Environment, Joseph A. Van Kuiken
Theses and Dissertations
The trade-off between accuracy and speed is a re-occurring dilemma in many facets of military performance evaluation. This is an especially important issue in the world of ISR. One of the most progressive areas of ISR capabilities has been the utilization of Unmanned Aircraft Systems (UAS). Many people believe that the future of UAS lies in smaller vehicles flying in swarms. We use the agent-based System Effectiveness and Analysis Simulation (SEAS) to create a simulation environment where different configurations of UAS vehicles can process targets and provide output that allows us to gain insight into the benefits and drawbacks of …
A Cost Assessment Of The Dayton Public Schools Vehicle Routing Problem, Frankie L. Woods Jr.
A Cost Assessment Of The Dayton Public Schools Vehicle Routing Problem, Frankie L. Woods Jr.
Theses and Dissertations
The routing and scheduling problem involves both constructing efficient routes to deliver goods or services to and from customers from a single depot or set of depots, as well as scheduling particular vehicles to these routes such that customers receive their goods within a specified time window. There have been several different methods developed to reduce the costs incurred in transporting goods or services (i.e. students) to customers (i.e. schools). This problem may be used to model many circumstances in logistics and public transportation. Several school districts do not utilize operations research techniques to minimize, as much as possible, the …
Robust Sensitivity Analysis For The Joint Improvised Explosive Device Defeat Organization (Jieddo) Proposal Selection Model, Christina J. Willy
Robust Sensitivity Analysis For The Joint Improvised Explosive Device Defeat Organization (Jieddo) Proposal Selection Model, Christina J. Willy
Theses and Dissertations
Throughout Operations Iraqi Freedom and Enduring Freedom, the Department of Defense (DoD) faced challenges not experienced in our previous military operations. The enemy’s unwavering dedication to the use of improvised explosive devices (IEDs) against the coalition forces continues to challenge the day-to-day operations of the current war. The Joint Improvised Explosive Device Defeat Organization’s (JIEDDO) proposal solicitation process enables military and non-military organizations to request funding for the development of Counter-Improvised Explosive Device (C-IED) projects. Decision Analysis (DA) methodology serves as a tool to assist the decision maker (DM) in making an informed decision. This research applies Value Focused Thinking …
A Hybrid Templated-Based Composite Classification System, Michael A. Turnbaugh
A Hybrid Templated-Based Composite Classification System, Michael A. Turnbaugh
Theses and Dissertations
An automatic target classification system contains a classifier which reads a feature as an input and outputs a class label. Typically, the feature is a vector of real numbers. Other features can be non-numeric, such as a string of symbols or alphabets. One method of improving the performance of an automatic classification system is through combining two or more independent classifiers that are complementary in nature. Complementary classifiers are observed by finding an optimal method for partitioning the problem space. For example, the individual classifiers may operate to identify specific objects. Another method may be to use classifiers that operate …
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 …
Boundary Avoidance Tracking: Consequences (And Uses) Of Imposed Boundaries On Pilot-Aircraft Performance, Ryan D. Blake
Boundary Avoidance Tracking: Consequences (And Uses) Of Imposed Boundaries On Pilot-Aircraft Performance, Ryan D. Blake
Theses and Dissertations
This thesis presents the results of research into the Boundary Avoidance Tracking (BAT) theory, which states that often pilots control an aircraft not in an attempt to maintain some condition, but to avoid some real or perceived boundaries. This pilot modeling concept was studied using over 30 pilots in simulator and flight tests. The pilot-aircraft system was evaluated with 3 different lateral-directional control models. Pilots were given a roll angle tracking task in the presence of shrinking boundaries. Pilots were also given a secondary task in some of the profiles in order to measure workload. Approximately 42 hours of simulation …
Tools For The Conceptual Design And Engineering Analysis Of Micro Air Vehicles, Mustafa Turan
Tools For The Conceptual Design And Engineering Analysis Of Micro Air Vehicles, Mustafa Turan
Theses and Dissertations
Micro Air Vehicles (MAV) are a subset of Unmanned Aircraft (UAS) that are up to two orders of magnitude smaller than manned systems. Near-Earth environments, such as forests, caves, tunnels and urban structures make reconnaissance, surveillance and search-and-rescue missions difficult and dangerous to accomplish. Therefore, MAVs are considered ideal for these types of missions. However, the data using full size aircraft is inadequate to characterize miniature aircraft parameters due to the lower Reynolds numbers and low aspect ratio (LAR) wings and impact of wing-propeller interactions. The main objectives of this research were to: collect and synthesize the available data/tools; create …