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Consistency Results For The Roc Curves Of Fused Classifiers, Kristopher S. Bjerkaas
Consistency Results For The Roc Curves Of Fused Classifiers, Kristopher S. Bjerkaas
Theses and Dissertations
The U.S. Air Force is researching the fusion of multiple classifiers. Given a finite collection of classifiers to be fused, one seeks a new classifier with improved performance. An established performance quantifier is the Receiver Operating Characteristic (ROC) curve, which allows one to view the probability of detection versus the probability of false alarm in one graph. Previous research shows that one does not have to perform tests to determine the ROC curve of this new fused classifier. If the ROC curve for each individual classifier has been determined, then formulas for the ROC curve of the fused classifier exist …
Design And Model Verification Of An Infrared Chromotomographic Imaging System, Daniel A. Lemaster
Design And Model Verification Of An Infrared Chromotomographic Imaging System, Daniel A. Lemaster
Theses and Dissertations
A prism chromotomographic hyperspectral imaging sensor is being developed to aid in the study of bomb phenomenology. Reliable chromotomographic reconstruction depends on accurate knowledge of the sensor specific point spread function over all wavelengths of interest. The purpose of this research is to generate the required point spread functions using wave optics techniques and a phase screen model of system aberrations. Phase screens are generated using the Richardson-Lucy algorithm for extracting point spread functions and Gerchberg-Saxton algorithm for phase retrieval. These phase screens are verified by comparing the modeled results of a blackbody source with measurements made using a chromotomographic …
The Kinetics Following Photolysis Of Nitrosyl Bromide, Lori A. Mahoney
The Kinetics Following Photolysis Of Nitrosyl Bromide, Lori A. Mahoney
Theses and Dissertations
One candidate for the development of a tunable laser in the mid-infrared for use as a defensive countermeasure against passive sensors exploits the nitric oxide (NO) transition at 5.4 μm. However, the difficulty with this mechanism is that when bromine (Br2) and NO are present in a mixture, nitrosyl bromide (BrNO) is also created. The absorption bands present in BrNO complicate the design of such a laser. This thesis determines the forward and reverse rate constants of the reaction of Br2 and NO to form BrNO following the photolysis of BrNO using Fourier Transform Infrared absorption spectroscopy. …
Forensic Analysis Of Digital Image Tampering, Jonathan R. Sturak
Forensic Analysis Of Digital Image Tampering, Jonathan R. Sturak
Theses and Dissertations
The use of digital photography has increased over the past few years, a trend which opens the door for new and creative ways to forge images. The manipulation of images through forgery influences the perception an observer has of the depicted scene, potentially resulting in ill consequences if created with malicious intentions. This poses a need to verify the authenticity of images originating from unknown sources in absence of any prior digital watermarking or authentication technique. This research explores the holes left by existing research; specifically, the ability to detect image forgeries created using multiple image sources and specialized methods …
Visual Unified Modeling Language For The Composition Of Scenarios In Modeling And Simulation Systems, Daniel E. Swayne
Visual Unified Modeling Language For The Composition Of Scenarios In Modeling And Simulation Systems, Daniel E. Swayne
Theses and Dissertations
The Department of Defense uses modeling and simulation systems in many various roles, from research and training to modeling likely outcomes of command decisions. Simulation systems have been increasing in complexity with the increased capability of low-cost computer systems to support these DOD requirements. The demand for scenarios is also increasing, but the complexity of the simulation systems has caused a bottleneck in scenario development due to the limited number of individuals with knowledge of the arcane simulator languages in which these scenarios are written. This research combines the results of previous AFIT efforts in visual modeling languages to create …
Pattern Search Ranking And Selection Algorithms For Mixed-Variable Optimization Of Stochastic Systems, Todd A. Sriver
Pattern Search Ranking And Selection Algorithms For Mixed-Variable Optimization Of Stochastic Systems, Todd A. Sriver
Theses and Dissertations
A new class of algorithms is introduced and analyzed for bound and linearly constrained optimization problems with stochastic objective functions and a mixture of design variable types. The generalized pattern search (GPS) class of algorithms is extended to a new problem setting in which objective function evaluations require sampling from a model of a stochastic system. The approach combines GPS with ranking and selection (R&S) statistical procedures to select new iterates. The derivative-free algorithms require only black-box simulation responses and are applicable over domains with mixed variables (continuous, discrete numeric, and discrete categorical) to include bound and linear constraints on …
Quantifying Initial Condition And Parametric Uncertainties In A Nonlinear Aeroelastic System With An Efficient Stochastic Algorithm, Daniel R. Millman
Quantifying Initial Condition And Parametric Uncertainties In A Nonlinear Aeroelastic System With An Efficient Stochastic Algorithm, Daniel R. Millman
Theses and Dissertations
There is a growing interest in understanding how uncertainties in flight conditions and structural parameters affect the character of a limit cycle oscillation (LCO) response, leading to failure of an aeroelastic system. Uncertainty quantification of a stochastic system (parametric uncertainty) with stochastic inputs (initial condition uncertainty) has traditionally been analyzed with Monte Carlo simulations (MCS). Probability density functions (PDF) of the LCO response are obtained from the MCS to estimate the probability of failure. A candidate approach to efficiently estimate the PDF of an LCO response is the stochastic projection method. The objective of this research is to extend the …
Improving Tcp Performance By Estimating Errors In A Long Delay, High Error Rate Environment, Stephanie E. Carroll
Improving Tcp Performance By Estimating Errors In A Long Delay, High Error Rate Environment, Stephanie E. Carroll
Theses and Dissertations
Interest in finding methods of improving TCP performance over satellite and wireless networks is high. This has been an active area of research within the networking community. This research develops an algorithm, CETEN-R for TCP to determine if a particular packet is lost due to congestion or corruption and react accordingly. An analysis of the performance of CETEN-R under a variety of conditions is studied and then compared to TCP Reno and TCP New Reno. When delay is high and the error rate is high CETEN-R showed a 77.5% increase in goodput over TCP New Reno and a 33.8% increase …
Using Time-Resolved Photoluminescence To Measure The Excitation And Temperature Dependence Of Carrier Relaxation In Mid-Wave Infrared Semiconductors, Kevin Cumblidge
Using Time-Resolved Photoluminescence To Measure The Excitation And Temperature Dependence Of Carrier Relaxation In Mid-Wave Infrared Semiconductors, Kevin Cumblidge
Theses and Dissertations
Research in the field of mid-wave infrared (MWIR) semiconductor photonic devices has led to applications in a variety of disciplines including atmospheric monitoring, optical communications, non-invasive glucose testing for diabetics, and infrared (IR) countermeasures. One of the limiting factors for improving the modulation rates of MWIR devices is the carrier relaxation time. This is the time required for energetic carriers to cool to the edge of their respective bands in a bulk semiconductor material, or to the bottom of a well through inter- and intra-sub-band scattering in a quantum well (QW) structure. From these lower energy states, they can then …
Derivation Of A Self-Consistent Auroral Oval Model Using The Auroral Boundary Index, Keith A. Anderson
Derivation Of A Self-Consistent Auroral Oval Model Using The Auroral Boundary Index, Keith A. Anderson
Theses and Dissertations
The position and intensity of the auroral oval has many implications for the Air Force from determining the effects of incoming electron flux on DoD systems to modeling the ionosphere to exploit current HF communications capabilities. The auroral morphology is a good indicator of the level at which space weather and its near-Earth consequences are occurring, and thus it is important to develop an auroral prediction model. However, since no purely physics-based models exist to describe the temporal and spatial evolution of the auroral zone, space weather practitioners and researchers are forced to produce statistical representations, “organized” by some relevant …
Comparative Study On The Use Of Coherent Radar-Derived Electric Fields Vs. Statistical Electric Fields For The Initialization Of A High-Latitude Ionospheric Model, Christopher M. Hogue
Comparative Study On The Use Of Coherent Radar-Derived Electric Fields Vs. Statistical Electric Fields For The Initialization Of A High-Latitude Ionospheric Model, Christopher M. Hogue
Theses and Dissertations
The structure and time development of the magnetosphere-ionosphere system have significant impacts on the Air Force and its mission. Specifically, an accurate knowledge of ionospheric plasma densities is important for the operation of many Air Force systems. This research analyzes plasma density structure development through comparing two distinct electric field models. The two models compared here are a commonly used statistical model created by Heppner and Maynard 1987, and a more recently developed model using real-time coherent radar measurements from the SuperDARN radar network. Ionospheric simulations were run using Utah State University s Time-Dependent Ionospheric Model (TDIM) with the two …
Estimating Equatorial F-Region Daytime Vertical E X B Drift Velocities From Ground-Based Magnetometer Measurements In The Philippine Longitude Sector, Shauna M. Kinkela
Estimating Equatorial F-Region Daytime Vertical E X B Drift Velocities From Ground-Based Magnetometer Measurements In The Philippine Longitude Sector, Shauna M. Kinkela
Theses and Dissertations
Ionospheric disturbances can severely impact Department of Defense (DoD) systems, such as radar. satellite. and navigation technologies. Forecasting disturbances and describing the Earth's ionosphere, in turn, relies upon innovative computer-based models that gather input parameters from ground and space-borne observations and empirical models for ionospheric drivers. Equatorial E x B drift velocities are significant input parameters that go into many ionospheric models, because they help describe vertical plasma motions near the magnetic equator. Previous work by Anderson, et al 2002 has demonstrated the ability to derive Peruvian longitude sector, daytime vertical E x B drifts from ground-based magnetometer data. The …
Cognitive Robot Mapping With Polylines And An Absolute Space Representation, Kennard R. Laviers, Gilbert L. Peterson
Cognitive Robot Mapping With Polylines And An Absolute Space Representation, Kennard R. Laviers, Gilbert L. Peterson
Faculty Publications
Robot mapping even today is one of the most challenging problems in robot programming. Most successful methods use some form of occupancy grid to represent a mapped region. This approach becomes problematic if the robot is mapping a large environment, the map quickly becomes too large for processing and storage. Rather than storing the map as an occupancy grid, our robot (equipped with sonars) sees the world as a series of connected spaces. These spaces are initially mapped as an occupancy grid in a room by room fashion. As the robot leaves a space, denoted by passing through a doorway, …
The United States Marine Corps Data Collaboration Requirements: Retrieving And Integrating Data From Multiple Databases, Pamela J. Cole
The United States Marine Corps Data Collaboration Requirements: Retrieving And Integrating Data From Multiple Databases, Pamela J. Cole
Theses and Dissertations
The goal of this research is to develop an information sharing and database integration model and suggest a framework to fully satisfy the United States Marine Corps collaboration requirements as well as its information sharing and database integration needs. This research is exploratory; it focuses on only one initiative: the IT-21 initiative. The IT-21 initiative dictates The Technology for the United States Navy and Marine Corps, 2000-2035: Becoming a 21st Century Force. The IT-21 initiative states that Navy and Marine Corps information infrastructure will be based largely on commercial systems and services, and the Department of the Navy must ensure …
Evolution Of Control Programs For A Swarm Of Autonomous Unmanned Aerial Vehicles, Kevin M. Milam
Evolution Of Control Programs For A Swarm Of Autonomous Unmanned Aerial Vehicles, Kevin M. Milam
Theses and Dissertations
Unmanned aerial vehicles (UAVs) are rapidly becoming a critical military asset. In the future, advances in miniaturization are going to drive the development of insect size UAVs. New approaches to controlling these swarms are required. The goal of this research is to develop a controller to direct a swarm of UAVs in accomplishing a given mission. While previous efforts have largely been limited to a two-dimensional model, a three-dimensional model has been developed for this project. Models of UAV capabilities including sensors, actuators and communications are presented. Genetic programming uses the principles of Darwinian evolution to generate computer programs to …
An Exploratory Analysis Of Factors Affecting Participation In Air Force Knowledge Now Communities Of Practice, David C. Fitzgerald
An Exploratory Analysis Of Factors Affecting Participation In Air Force Knowledge Now Communities Of Practice, David C. Fitzgerald
Theses and Dissertations
As the AF continues to lose its knowledge base through retirements and downsizing, the need to get maximum use from the remaining knowledge base becomes increasingly important. In their efforts to help the Department of Defense and the Air Force Chief Information Officer (AFCIO) meet their knowledge management goals, Air Force Material Command (AFMC) has been working to implement the use of communities of practice. A primary goal of AFMC/DRW , the AF Knowledge Now program office, and the office of the AFCIO is to increase effectiveness and participation within communities of practice. The goal of this research is to …
Development Approaches Coupled With Verification And Validation Methodologies For Agent-Based Mission-Level Analytical Combat Simulations, Lance E. Champagne
Development Approaches Coupled With Verification And Validation Methodologies For Agent-Based Mission-Level Analytical Combat Simulations, Lance E. Champagne
Theses and Dissertations
This research investigated the applicability of agent-based combat simulations to real-world combat operations. An agent-based simulation of the Allied offensive search for German U-Boats in the Bay of Biscay during World War II was constructed, extending the state-of-the-art in agent-based combat simulations, bridging the gap between the current level of agent-like combat simulations and the concept of agent-based simulations found in the broader literature. The proposed simulation advances agent-based combat simulations to “validateable” mission-level military operations. Simulation validation is a complex task with numerous, diverse techniques available and levels of validation differing significantly among simulations and applications. This research presents …
Deviation Of Time-Resolved Luminescence Dynamics In Mwir Semiconductor Materials From Carrier Recombination Theory Predictions, Peter M. Johnson
Deviation Of Time-Resolved Luminescence Dynamics In Mwir Semiconductor Materials From Carrier Recombination Theory Predictions, Peter M. Johnson
Theses and Dissertations
Time resolved luminescence spectroscopy was used to characterize luminescence decay curves for a bulk InAs sample and an InAsSb type-I quantum-well sample over the first 3ns following excitation. The luminescence decay curves were then converted to carrier densities and used to find recombination coefficients that provided the least-squared-error solution of the rate equation describing carrier recombination. Recombination coefficients describing Shockley Read-Hall (ASRH) radiative (Brad) and Auger (CAug) recombination were determined at two different temperatures and four excitation powers, then analyzed for consistency and physical significance. For all of the resulting least …
An Analysis Of Electromagnetic Interference (Emi) Of Ultra Wideband(Uwb) And Ieee 802.11a Wireless Local Area Network (Wlan) Employing Orthogonal Frequency Division Multiplexing (Ofdm), Juan Lopez Jr.
Theses and Dissertations
Military communications require the rapid deployment of mobile, high-bandwidth systems. These systems must provide anytime, anywhere capabilities with minimal interference to existing military, private, and commercial communications. Ultra Wideband (UWB) technology is being advanced as the next generation radio technology and has the potential to revolutionize indoor wireless communications. The ability of UWB to mitigate multipath fading, provide high-throughput data rates (e.g., greater than 100 Mbps), provide excellent signal penetration (e.g., through walls), and low implementation costs makes it an ideal technology for a wide range of private and public sector applications. Preliminary UWB studies conducted by The Institute for …
An Exploration Of Cultural Factors Affecting Use Of Communities Of Practice, Peter L. Hinrichsen
An Exploration Of Cultural Factors Affecting Use Of Communities Of Practice, Peter L. Hinrichsen
Theses and Dissertations
On-line communities of practice are potentially powerful social learning networks that can improve organizational performance. Unfortunately, administrators of on-line communities of practice report that community members do not take full advantage of this potential. This study used Shaw and Tuggle's (2003) factors of knowledge management (KM) culture affecting organizational acceptance of a knowledge management initiative to explore this issue. It was hypothesized that respondents whose communities of practice possessed higher average community use per member would rate KM culture variables higher than respondents whose communities possessed a lower average community use. An analysis of survey data collected from Air Force …
Exploring Content Management Issues In Air Force On-Line Communities Of Practice: A Multiple Case Study Approach, Jaime A. Rodriguez
Exploring Content Management Issues In Air Force On-Line Communities Of Practice: A Multiple Case Study Approach, Jaime A. Rodriguez
Theses and Dissertations
The practice of content management attempts regardless of platform to ensure that pertinent information is current, relevant, and presented in a usable manner. The Air Force Communities of Practice (CoPs) are hosted by AFMC/DRW, The purpose of these CoPs is to facilitate and promote an environment of capturing and sharing knowledge among members of a particular field task or common practice. As the host for these CoPs AFMC/DRW desires to increase CoP participation efficiency and effectiveness. Addressing existing or potential content management issues will help do so. This multiple-case study research observed and interviewed managers and members of eight active …
Comparison Of A Conceptual Model And Objective Indicators Of Extratropical Transition In The Western North Pacific, Gregory D. Fox
Comparison Of A Conceptual Model And Objective Indicators Of Extratropical Transition In The Western North Pacific, Gregory D. Fox
Theses and Dissertations
The primary purpose of this research is to provide guidance to forecasters from the Joint (Air Force/Navy) Typhoon Warning Center (JTWC) in Pearl Harbor to use in differentiating between the stages of extratropical transition (ET) of tropical cyclones (TCs). Not only is ET relevant to the Department of Defense, since JTWC stops providing TC warnings once they have undergone ET, but it is also applicable to the meteorological community since there currently "is no commonly accepted definition of ET" (Jones et al 2003). This research compares the results of a conceptual model of ET using subjective satellite analysis with the …
Automating Security Protocol Analysis, Stephen W. Mancini
Automating Security Protocol Analysis, Stephen W. Mancini
Theses and Dissertations
When Roger Needham and Michael Schroeder first introduced a seemingly secure protocol 24, it took over 18 years to discover that even with the most secure encryption, the conversations using this protocol were still subject to penetration. To date, there is still no one protocol that is accepted for universal use. Because of this, analysis of the protocol outside the encryption is becoming more important. Recent work by Joshua Guttman and others 9 have identified several properties that good protocols often exhibit. Termed Authentication Tests, these properties have been very useful in examining protocols. The purpose of this research is …
Forecasting Advective Sea Fog With The Use Of Classification And Regression Tree Analyses For Kunsan Air Base, Danielle M. Lewis
Forecasting Advective Sea Fog With The Use Of Classification And Regression Tree Analyses For Kunsan Air Base, Danielle M. Lewis
Theses and Dissertations
Advective sea fog frequently plagues Kunsan Air Base (AB), Republic of Korea, in the spring and summer seasons. It is responsible for a variety of impacts on military operations, the greatest being to aviation. To date, there are no suitable methods developed for forecasting advective sea fog at Kunsan, primarily due to a lack of understanding of sea fog formation under various synoptic situations over the Yellow Sea. This work explored the feasibility of predicting sea fog development with a 24-hour forecast lead time. Before exploratory data analysis was performed, a geographical introduction to the region was provided along with …
Verification Of Meteorological Data Reports From The Rq-4a Global Hawk Unmanned Aerial Vehicle, Steven M. Callis
Verification Of Meteorological Data Reports From The Rq-4a Global Hawk Unmanned Aerial Vehicle, Steven M. Callis
Theses and Dissertations
Unmanned aerial vehicles (UAVs) have onboard sensors that continuously record weather data during their missions. This information is extremely valuable to both the meteorological and UAV communities with numerous potential benefits, which include improved weather forecast products and additional weather intelligence for military planners. The value of any dataset is directly related to its accuracy and this research determined the accuracy of weather data obtained from a particular UAV, the RQ-4A Global Hawk. This was accomplished through statistical analysis and comparisons with upper-air data and Atmospheric Slant Path Analysis Model (ASPAM) profiles of the atmosphere. Recommendations are provided for the …
Optical Characterization And Modeling Of Compositionally Matched Indium Arsenide-Antimonide Bulk And Multiple Quantum Well Semiconductors, Scott C. Phillips
Optical Characterization And Modeling Of Compositionally Matched Indium Arsenide-Antimonide Bulk And Multiple Quantum Well Semiconductors, Scott C. Phillips
Theses and Dissertations
Indium arsenide-antimonide (InAsSb) semiconductors have been determined to emit in the 3-5 micrometer range, the window of interest for countermeasures against infrared electro-optical threats. This experiment set out to cross the bulk to quantum well characterization barrier by optically characterizing two sets of compositionally matched type I quantum well and bulk well material samples. Absorption measurements determined the band gap energy of the bulk samples and the first allowed subband transition for the quantum wells. By collecting absorption spectra at different temperatures, the trend of the energy transitions was described by fitting a Varshni equation to them. The expected result …
Developing A Forecast Tool For Cloud-To-Ground Lightning In The North Central And Northeastern United States, Manuel I. Folsom Jr.
Developing A Forecast Tool For Cloud-To-Ground Lightning In The North Central And Northeastern United States, Manuel I. Folsom Jr.
Theses and Dissertations
Cloud-to-ground (CG) lightning is a hazard to the Air Force for both air and ground operations Forecasting CG lightning is a necessary and extremely important requirement for Air Force meteorologists and forecasters. The 15th Operational Weather Squadron requested a forecast tool capable of predicting CG lightning within a 25 and 10 nautical mile radius of the 13 military locations in their area of responsibility. To fulfill their request, forecast decision tools were created using a Classification and Regression Tree (CART) data analysis program. Four decision trees were produced for each location using the period of record from March through September, …
Verification Of The Mountain Wave Forecast Model's Stratospheric Turbulence Forecasts Using Sounding Data And Pilot Reports, Scott M. Miller
Verification Of The Mountain Wave Forecast Model's Stratospheric Turbulence Forecasts Using Sounding Data And Pilot Reports, Scott M. Miller
Theses and Dissertations
Since stratospheric turbulence (Stratoturb) is becoming an increased concern to the Air Force, the threat of damage to aircraft must be addressed. Therefore, the Air Force Weather Agency (AFWA) requests an accurate Stratoturb forecast model. In 2002, The Mountain Wave Forecast Model (MWFM) was modified in order to develop a Stratoturb forecast tool. Turbulence forecasts generated twice daily by the MWFM for locations over East Asia over a period of thirty days were compared to output from the Rawindsonde Observation (RAOB) program to determine if the model agreed with the program output. Although the results were promising, verification by aircraft …
A Statistically-Based Method For Predicting Fog And Stratus Dissipation, Louis L. Lussier Iii
A Statistically-Based Method For Predicting Fog And Stratus Dissipation, Louis L. Lussier Iii
Theses and Dissertations
The method is a success in producing forecasts for ceiling and visibility criteria that had never previously been examined. It is suggested that the 15 OWS incorporate this methodology into their operational forecasting routine. Ceiling forecasts at Dover AFB and McGuire AFB show improvements over conditional climatology ranging from 1-51% with an average improvement of 19.2% when verified against an independent data set. McGuire AFB visibility forecasts show an average improvement over conditional climatology of 3%. These findings are of particular importance to the Air Force in general and specifically to the 15th Operational Weather Squadron (15 OWS) who produces …
Dust Storm Forecasting For Al Udeid Ab, Qatar: An Empirical Analysis, Kevin S. Bartlett
Dust Storm Forecasting For Al Udeid Ab, Qatar: An Empirical Analysis, Kevin S. Bartlett
Theses and Dissertations
Dust storms are extreme weather events that have strong winds laden with visibility reducing and operations limiting dust, The Central Command Air Forces (CENTAF) 28th Operational Weather Squadron (OWS) is ultimately responsible for forecasting weather in the vast, data denied region of Southwest Asia in support of daily military and humanitarian operations. As a result, the 28th OWS requests a simplified forecasting tool to help predict mesoscale dust events that affect coalition operations at Al Udeid AB, Qatar. This research satisfies the 28th OWS request through an extensive statistical analysis of observational data depicting seasonal dust events over the past …