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Chromium Concentration Bias In The Particle Size Distribution Of Primer Overspray, Joseph M. Fox
Chromium Concentration Bias In The Particle Size Distribution Of Primer Overspray, Joseph M. Fox
Theses and Dissertations
Air Force aircraft-painting operations create clouds of paint overspray that contain strontium chromate, a confirmed carcinogen, which poses an exposure hazard to painters. It is often assumed that all particles in paint overspray have the same chemical composition as the original paint mixture, however differences in composition may occur in various particle sizes. Because particle size affects where in the respiratory system a particle deposits, actual exposures to a specific chemical may vary. Paint particles greater than 2.5 µm are deposited in the upper respiratory system and will be eliminated by physiological removal mechanisms. Particles less than 2.5 µm will …
Damage Identification In A Real Structure Using Resonant And Anti-Resonant Frequencies, Douglas E. Gaeta
Damage Identification In A Real Structure Using Resonant And Anti-Resonant Frequencies, Douglas E. Gaeta
Theses and Dissertations
There exists a need to remotely monitor the structural integrity of large space structures without costly manned missions. This work focused on further damage detection characterization of the Air Force Institute of Technology's Flexible Truss Experiment (FTE). The FTE is intended to be representative of a large space structure. Several damage detection algorithms were developed and tested for the FTE using 112 different damage conditions and the one undamaged condition. The algorithms were trained using two frequency response functions (FRFs) from each damage case and then tested using the same two FRFs, but from newly acquired data. A data reduction …
Modeling Chlorinated Ethene Removal In Constructed Wetlands: A System Dynamics Approach, Colby D. Hoefar
Modeling Chlorinated Ethene Removal In Constructed Wetlands: A System Dynamics Approach, Colby D. Hoefar
Theses and Dissertations
The purpose of this study is to gain understanding of the dynamics of the processes that degrade Perchloroethene (PCE) to ethylene, or carbon dioxide (CO2), within the confines of a constructed wetland. A system dynamics approach will be used. This model is focused on identifying and optimizing the naturally occurring processes in stratified wetland sediment that reduce mass, toxicity, mobility, volume or concentration of contaminants in groundwater. Contaminant fate and transport within a wetland system is extremely complex and the mechanisms that drive wetland behavior are dynamic. Confidence in the model was built through verification and testing. Reasonable …
Tunable Mid-Ir Optical Parametric Oscillator Using Periodically Poled Rubidum Titanyl Arsenate, Frank J. Glavic
Tunable Mid-Ir Optical Parametric Oscillator Using Periodically Poled Rubidum Titanyl Arsenate, Frank J. Glavic
Theses and Dissertations
Tunable sources of coherent radiation are needed for a variety of military and commercial applications, including infrared countermeasures and atmospheric remote sensing. This research investigates a tunable mid-infrared coherent source using periodically-poled rubidium titanyl arsenate (PPRTA) as a quasi-phase matched (QPM) optical parametric oscillator (OPO). The advantages of PPRTA over periodically poled lithium niobate (PPLN) are presented. Quasi-phase matching and periodic poling theory are discussed, along with some important historical results and current developments. Experimental setups for determining threshold, conversion efficiency, pump depletion, and beam quality are presented along with experimental results. The research effort is focused on characterizing PPRTA …
An Information Visualization Solution For The Analysis Of The Afm Simulation Output Data, Stuart H. Kurkowski
An Information Visualization Solution For The Analysis Of The Afm Simulation Output Data, Stuart H. Kurkowski
Theses and Dissertations
With the advancement of computer hardware and software computer simulations are now able to run faster and track more elements than ever before burdening the analyst with more and more data to analyze. Air Mobility Command's (AMC) Airlift Flow Model (AFM) is the Air Force's logistics simulator that simulates multi-day mobility scenarios in a matter of minutes producing megabytes of output data. Because the analysts' needs for summaries, trends, and comparisons of the data have surpassed the capabilities of current desktop spreadsheet analysis techniques new tools are needed.
Techniques For Forecasting The Cessation Of Lightning At Cape Canaveral Air Station And The Kennedy Space Center, Michael W. Holmes
Techniques For Forecasting The Cessation Of Lightning At Cape Canaveral Air Station And The Kennedy Space Center, Michael W. Holmes
Theses and Dissertations
The focus of this research effort is directed toward identifying new methods of forecasting the cessation of lightning along the Central Atlantic Coast of Florida. Cloud-to-ground lightning flashes place Air Force (AF) personnel and assets at risk almost daily at this location. Providing a more accurate method of forecasting the cessation of lightning would allow for safer and more efficient execution of AF operations. A data set consisting of 40 thunderstorm cases was identified within a 90 nautical miles (nmi) region surrounding the Melbourne, Florida WSR-88D (KMLB) site. Each case falls between the months of May and September and the …
A Human-Centered Approach For Designing Decision Support Systems, Sean G. Kern
A Human-Centered Approach For Designing Decision Support Systems, Sean G. Kern
Theses and Dissertations
The choice to include the human in the decision process affects four key areas of system design: problem representation, system analysis and design, solution technique selection, and interface requirements specification. I introduce a design methodology that captures the necessary choices associated with each of these areas. In particular I show how this methodology is applied to the design of an actual decision Support system for satellite operations scheduling. Supporting the user's ability to monitor the actions of the system and to guide the decision process of the system are two key considerations in the successful design of a decision support …
Collection Of Detonation Signatures And Characterization Of Spectral Features, Jay A. Orson
Collection Of Detonation Signatures And Characterization Of Spectral Features, Jay A. Orson
Theses and Dissertations
The remote observations of the temporal and spectral characteristics of the infrared (IR) emissions from exploding ordnance have been correlated with explosion conditions. A Bomem MR-154 Fourier Transform Interferometer with two detectors, InSb and HgCdTe, and a 75 mrad telescope was used to record spectra in the 1.3 - 20 µm range. Data was collected at spectral resolutions of 16 cm-1 and 4 cm-1 and temporal resolutions of 0.045 s and 0.123 s respectively. Two field tests were conducted: (1) a set of dynamic drop explosions and (2) a series of static detonations. In most events, the temporal …
Toxicity Of Tolyltriazole To Gram-Positive Coccus Microorganisms, Heather L. Mitchell
Toxicity Of Tolyltriazole To Gram-Positive Coccus Microorganisms, Heather L. Mitchell
Theses and Dissertations
Maintaining safe flight operations, military and civilian, in cold weather requires the use of de-icing fluids. Glycols, the primary component of de-icers, have been extensively studied. Water and additives such as corrosion inhibitors and other performance enhancing chemicals make up the remaining portion of de-icing fluids. Little research has been conducted on the additives, but several are suspected toxins to microorganisms, therefore the EPA regulates the disposal of spent de-icing fluids. Tolyltriazole, a corrosion inhibitor found in de-icing fluids, is a suspected human carcinogen. It is also known to be moderately toxic to microorganisms based on Microtox results. The purpose …
Active Multispectral Bidirectional Reflectance Distribution Function Measurement System, Mark J. Proctor
Active Multispectral Bidirectional Reflectance Distribution Function Measurement System, Mark J. Proctor
Theses and Dissertations
Today's highly technical battlefield environment dictates the need for a method of standoff target identification, which reduces risk to personnel and equipment. It is widely known that a given material will react differently to incident radiation than a dissimilar material. Certain materials may respond specularly while others tend to be diffuse. By measuring these responses, materials can be identified by comparison with a known database. One method of building such a database for target recognition is by employing an active multi spectral bidirectional reflectance distribution function (BRDF) measurement system. In the following text, such a system is developed and tested …
A Component Based Approach To Agent Specification, David J. Robinson
A Component Based Approach To Agent Specification, David J. Robinson
Theses and Dissertations
The Air Force, as well as all of industry, is currently faced with the problem of having to produce larger and more complex software systems that run efficiently and reliably as well as being extensible and maintainable. This research addresses this problem by developing a knowledge representation language that can be used to unambiguously specify and design software systems in a verifiable, efficient, and understandable manner. The language is a combination of object-oriented and component-based methodologies and makes use of both graphics and text to represent information. Although designed for the development of any type of software system, the language …
A Study Of Morning Radiation Fog Formation, Jimmie L. Trigg Jr.
A Study Of Morning Radiation Fog Formation, Jimmie L. Trigg Jr.
Theses and Dissertations
This research focuses on developing a linear regression formula that forecasters in the Midwest can use to accurately anticipate the formation of radiation fog. This was accomplished in three stages. First a study of the surface and upper air parameters and processes required to develop radiation fog were identified and explored. Next, a linear regression technique was applied to the 23 parameters identified. The top four indicators were then reprocessed and a new linear regression equation was developed. Finally, the new regression equation was compared to an existing fog forecasting technique. The existing forecast technique selected was the 2nd Weather …
Optical Metrology Of Adaptive Membrane Mirrors, John W. Wagner
Optical Metrology Of Adaptive Membrane Mirrors, John W. Wagner
Theses and Dissertations
Current space-based imaging platforms are significantly constrained in both size and weight by the launch vehicle. Increased payload size and weight results in increased cost and a decrease in launch responsiveness. The USAF Scientific Advisory Board (SAB) identified "Large lightweight structures for optics and antennas" as a revolutionary primary technology to be developed for the Air Force of the 21st Century. A membrane primary mirror in a space-based imaging system has the ability to overcome current payload constraints and meet evolutionary needs of the future. The challenge of membrane optics in space is the process of implementing adaptive optics technology …
A Comparative Analysis Of Cockpit Display Development Tools, Matthew J. Gebhardt
A Comparative Analysis Of Cockpit Display Development Tools, Matthew J. Gebhardt
Theses and Dissertations
Currently, no standard methodology exists that enables cockpit display engineers to evaluate software tools used in the development of graphical cockpit displays. Furthermore, little research has been accomplished in comparing current software development tools with traditional hand-coded methods, This research effort discusses a framework for analyzing cockpit display software development tools and follows through with a detailed analysis comparing today's hand-coding standard, OpenGL, with two of today's cockpit display software development suites, Virtual Application Prototyping System (VAPS) and Display Editor. The comparison exploits the analysis framework establishing the advantages and disadvantages of the three software development suites. The analysis framework …
Data Warehouse Techniques To Support Global On-Demand Weather Forecast Metrics, Meriellen C. Joga
Data Warehouse Techniques To Support Global On-Demand Weather Forecast Metrics, Meriellen C. Joga
Theses and Dissertations
Air Force pilots and other operators make crucial mission planning decisions based on weather forecasts; therefore, the ability to forecast the weather accurately is a critical issue to Air Force Weather (AFW) and its customers. The goal of this research is to provide Air Force Weather with a methodology to automate statistical data analysis for the purpose of providing on-demand metrics. A data warehousing methodology is developed and applied to the weather metrics problem in order to present an option that will facilitate on-demand metrics. On-line analytical processing (OLAP) and data mining solutions are also discussed.
Computational Fluid Dynamics Testing For Drag Reduction Of An Aircraft Laser Turret, Gregory J. Schwabacher
Computational Fluid Dynamics Testing For Drag Reduction Of An Aircraft Laser Turret, Gregory J. Schwabacher
Theses and Dissertations
A computational study was conducted on the use of aft-mounted fairings for passive drag reduction on a sphere at Re=866,000. The sphere dimensions and operating Reynolds number were selected to approximate the flow around a proposed aircraft laser turret for which experimental data was available. To establish the validity of the computational model, flow predictions were compared to sphere data available in the open literature. The model, exercised in both the laminar and turbulent modes, showed good agreement with the published data. Two proposed laser turret fairings were then evaluated computationally: a large fairing (beginning at 49.5 degrees past the …
Use Of Genetic Algorithms To Characterize Groundwater Contamination Source Areas, Chaz M. Williamson
Use Of Genetic Algorithms To Characterize Groundwater Contamination Source Areas, Chaz M. Williamson
Theses and Dissertations
In this work, genetic algorithms (GAs) were used to help interpret tracer breakthrough curves from partitioning interwell tracer tests (PITTs) conducted at Hill AFB, Utah by researchers from the University of Florida. Two transport models were developed to simulate tracer transport in the test cells. One model assumed the cell consisted of multiple layers, and that transport in each layer could he described by the one-dimensional advective/dispersive equation. The second model also assumed multiple layers, and modeled transport in the individual layers as advective transport through 100 tubes. Transport times were represented by a stochastic (lognormal) distribution. The model solutions …
A Greedy Multiple-Knapsack Heuristic For Solving Air Mobility Command’S Intratheater Airlift Problem, Nicholas J. Zeisler
A Greedy Multiple-Knapsack Heuristic For Solving Air Mobility Command’S Intratheater Airlift Problem, Nicholas J. Zeisler
Theses and Dissertations
This research develops a methodology using a greedy heuristic to solve Air Mobility Command's intratheater airlift scenario as a multiple knapsack problem. The objective is to maximize throughput in a theater given a vehicle mixture and assignment scheme. The model allows for a heterogeneous, user defined vehicle mix in a theater consisting of up to five bed down locations and up to seven forward operating locations. First, we preprocess routes, eliminating the large number of unattractive route choices in the problem. Then using a greedy heuristic, we select routes and assign them to aircraft located at any or all of …
An Analysis In Cloud-To-Ground Lightning Over Land Versus Water, Elizabeth A. Boll
An Analysis In Cloud-To-Ground Lightning Over Land Versus Water, Elizabeth A. Boll
Theses and Dissertations
Understanding lightning characteristics over land and water is vital to achieving optimal safety and success in Air Force missions. Lightning safety rules are often based on experience rather than a scientific understanding of lightning. Examining lightning characteristics over water and land will assist in a better understanding of lightning and provide answers that can protect human lives and property. Water and land have different compositions and surface conductivity values. A lightning stroke is detected through a change in the electro-magnetic field at the surface. The change in surface conductivity values from land to water can affect the detection of a …
A 3d Display System For Lightning Detection And Ranging (Ldar) Data, Michael W. Darwin
A 3d Display System For Lightning Detection And Ranging (Ldar) Data, Michael W. Darwin
Theses and Dissertations
Lightning detection is an essential part of safety and resource protection at Cape Canaveral. In order to meet the unique needs of launching space vehicles in the thunderstorm prone Florida environment, Cape Canaveral has the only operational three- dimensional (3D) lightning detection network in the world, the Lightning Detection and Ranging (LDAR) system. Although lightning activity is detected in three dimensions, the current LDAR display, developed 20 years ago, is two-dimensional. This thesis uses modern three-dimensional graphics, object-oriented software design, and innovative visualization techniques to develop a 3D visualization application for LDAR data.
A Group Theoretic Tabu Search Approach To The Traveling Salesman Problem, Shane N. Hall
A Group Theoretic Tabu Search Approach To The Traveling Salesman Problem, Shane N. Hall
Theses and Dissertations
The traveling salesman problem (TSP) is a combinatorial optimization problem that is mathematically modeled as a binary integer program. The TSP is a very important problem for the operations research academician and practitioner. This research demonstrates a Group Theoretic Tabu Search (GTTS) Java algorithm for the TSP. The tabu search metaheuristic continuously finds near-optimal solutions to the TSP under various different implementations. Algebraic group theory offers a more formal mathematical setting to study the TSP providing a theoretical foundation for describing tabu search. Specifically, this thesis uses the Symmetric Group on n letters, S(n), which is the set of all …
Chromate Dissociation From Primer Paint In Simulated Lung Fluid, Tiffany J. R. Morgan
Chromate Dissociation From Primer Paint In Simulated Lung Fluid, Tiffany J. R. Morgan
Theses and Dissertations
OSHA has proposed a new strontium chromate exposure standard that would potentially cause Air Force paint facilities to be in violation of the proposed standard if adopted. This proposed reduction make the continued use of chromate containing primer paints very difficult. There is currently no acceptable replacements for chromate containing primer paints on AF aircraft. This study suggests that paint particles with chromate bound in primer paint may be unavailable for bodily absorption if inhaled and a reduced standard for painting applications may be unnecessary. Primer paint overspray was collected into simulated lung fluid (SLF) and allowed 6 hr, 24 …
A Method Of Focusing The Attention Of The Decision-Maker On Uncertain Information, John F. Moesner Iv
A Method Of Focusing The Attention Of The Decision-Maker On Uncertain Information, John F. Moesner Iv
Theses and Dissertations
Military decision-makers need to be able to synthesize large amounts of information quickly and make accurate and timely decisions. However, all too often, when a decision-maker is bombarded with important information that has an uncertainty associated with it, that information is often neglected. One method of dealing with this type of information overload is through proper data orientation. By reducing the clutter of irrelevant information, the proportions of useful and relevant data can be increased. At the same time, the attention of the decision-maker is directed to the critical tasks or centers of gravity. The WATCHDOG Decision Support Tool is …
Temperature Determination In An I2 Gas Using Dopper-Limited Saturation Spectroscopy, James W. Myers Jr.
Temperature Determination In An I2 Gas Using Dopper-Limited Saturation Spectroscopy, James W. Myers Jr.
Theses and Dissertations
Saturation spectroscopy techniques were used to demonstrate the ability to make spatially resolved temperature measurements by exploiting the B3 ∏(O+u) - X1 Σ ;(O+g) electronic transition in molecular iodine (I2). Doppler-free saturation spectroscopy measurements resulted in hyperfine spectral profiles for the P(7O) 17-1 and P(53) 19-2 ro-vibrational transitions between the electronic levels. Doppler-limited saturation spectroscopy, an adaptation of the Doppler-free technique in which beams propagate in the same direction and cross within the gas sample, allowed for the measurement of spatially resolved Doppler profiles for the same transitions. The profiles were measured …
Determining The Horizontal Distance Distribution Of Cloud-To-Ground Lightning, Tamara L. Parsons
Determining The Horizontal Distance Distribution Of Cloud-To-Ground Lightning, Tamara L. Parsons
Theses and Dissertations
This research effort attempted to quantify what constitutes a safe distance when lightning is present. The method used in this research project groups lightning flashes into clusters using spatial and temporal constraints. However, not all flashes meet the time and distance criteria for clustering and remained outside of tile grouped flashes and as such are identified as isolated flashes. These isolated flashes are outliers in the data set, but are precisely the flashes that prove most dangerous. For this reason not only were the distances between each flash and cluster center studied, but also the distances between each isolated flash …
A Validation Assessment Of The Storm Air-To-Air Prototype Algorithm, David M. Pugh
A Validation Assessment Of The Storm Air-To-Air Prototype Algorithm, David M. Pugh
Theses and Dissertations
A validation assessment of the new STORM air-to-air prototype algorithm is accomplished using structural and output validation techniques. In the structural validation phase, the algorithms, code, and assumptions are evaluated to determine if the implementation of the model will match the intent of the designers. The components of the algorithm are compared to its predecessor, THUNDER, to evaluate if the prototype nnproves upon the weaknesses of THUNDER. In the output validation phase, the results of the model are evaluated to determine the extent to which the implementation of the model matches expected outcomes. Sensitivity analysis is presented to provide insight …
Nonuniformly Spaced Array Elements, Daniel R. Richards Jr.
Nonuniformly Spaced Array Elements, Daniel R. Richards Jr.
Theses and Dissertations
This thesis provides a method to reduce physical resource requirements along with cost reduction in Space Based Radar (SBR) platforms, and provides a rule of thumb for randomization effects on arrays. A trend analysis is performed on 4, 8, 12, and 16 square meter arrays. Three aperiodic thinning approaches are examined. They are an equal current density element distribution, a random periodic grid of elements, and random element distribution based a peak sidelobe indicator. According to the metrics used, the statistical and deterministic array thinning approaches performed best for these small arrays. However, the statistical arrays have a scan angle …
Knowledge Base Support For Design And Synthesis Of Multi-Agent Systems, Marc J. Raphael
Knowledge Base Support For Design And Synthesis Of Multi-Agent Systems, Marc J. Raphael
Theses and Dissertations
AgentTool is an AFIT-produced, AFOSR-sponsored multi-agent system (MAS) development tool intended for production of MASs that meet military requirements. This research focuses on enabling MAS design and synthesis tools like agentTool to store, retrieve, and filter persistent, reusable, and reliable agent domain knowledge. This "enabling" is vital if such tools are expected to produce consistent, maintainable, and verifiable agent applications on short timetables. Enabling requires: 1) modeling the agent knowledge domain, 2) designing and employing a persistent knowledge base, and 3) bridging that domain model to the knowledge base with an extensible domain interchange grammar. The achieved interchange grammar, called …
Timing Of Thunderstorm Occurrence For Cape Canaveral, Florida, Thomas G. Renwick
Timing Of Thunderstorm Occurrence For Cape Canaveral, Florida, Thomas G. Renwick
Theses and Dissertations
This research is concerned with improving an existing algorithm to accurately forecast thunderstorm starting times for Cape Canaveral, Florida. This was accomplished by investigating different linear regression techniques than those used in the existing algorithm. The result is three new thunderstorm start time algorithms. The forecast start times of these new algorithms were then compared to actual thunderstorm start times to determine which method produced the most accurate results. The average thunderstorm starting time was also calculated from the data. This time was also compared to actual thunderstorm starting time. Upon examination of the various start times produced, it was …
Atmospheric Temperature Profiles By Ground-Based Infrared Spectrometer Measurements, Jon M. Saul
Atmospheric Temperature Profiles By Ground-Based Infrared Spectrometer Measurements, Jon M. Saul
Theses and Dissertations
A method to recover atmospheric temperature profiles using a ground-based Fourier Transform Infrared spectrometer was investigated. The method used a difference form of the radiative transfer equation, a Bomem MR series Fourier Transform Infrared Spectrometer to collect atmospheric radiance values, and the Phillips Laboratory Expert- assisted User Software (PLEXUS) atmospheric radiance model, to recover an atmospheric temperature profile. The method researched uses radiance values from both the spectrometer measurements and the atmospheric model, along with kernel functions calculated by the atmospheric model as input to a difference form of the radiation transfer equation. From this the change in brightness temperatures …