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Active Processor Scheduling Using Evolution Algorithms, David J. Caswell
Active Processor Scheduling Using Evolution Algorithms, David J. Caswell
Theses and Dissertations
The allocation of processes to processors has long been of interest to engineers. The processor allocation problem considered here assigns multiple applications onto a computing system. With this algorithm researchers could more efficiently examine real-time sensor data like that used by United States Air Force digital signal processing efforts or real-time aerosol hazard detection as examined by the Department of Homeland Security. Different choices for the design of a load balancing algorithm are examined in both the problem and algorithm domains. Evolutionary algorithms are used to find near-optimal solutions. These algorithms incorporate multiobjective coevolutionary and parallel principles to create an …
Power Scaling Feasibility Of Chromium-Doped Ii-Vi Laser Sources And The Demonstration Of A Chromium-Doped Zinc Selenide Face-Cooled Disk Laser, Jason B. Mckay
Power Scaling Feasibility Of Chromium-Doped Ii-Vi Laser Sources And The Demonstration Of A Chromium-Doped Zinc Selenide Face-Cooled Disk Laser, Jason B. Mckay
Theses and Dissertations
Tunable lasers in the 2-4 µm wavelength range are needed for Air Force sensor applications. Chromium-doped II-VI materials are a promising class of laser material for tunable operation in this wavelength range, but until recently had not produced enough output power to meet application requirements. This dissertation investigates Cr2+:II-VI material properties and potential laser designs, then experimentally demonstrates and analyzes the performance of a Cr2+:ZnSe disk laser design that can produce sufficient output power. Cr2+:II-VI laser materials are found to be susceptible to overheating and thermal lensing, but are otherwise satisfactory laser materials. The …
High Energy Laser Pointing Through Extended Turbulence, Jason A. Tellez
High Energy Laser Pointing Through Extended Turbulence, Jason A. Tellez
Theses and Dissertations
The airborne laser (ABL) uses adaptive optics to compensate the atmospheric turbulence between the ABL and the target. The primary purpose of this compensation is to increase the energy density of the energy laser at the target. However, the specifics of the engagement scenario require the tracking point of reference and the adaptive optics point of reference to be located at different points on the target. This research considers the effects of tracking a target in one direction while compensating for atmospheric turbulence in a different directions. The target references used are a point source and a rectangle, while a …
Finite Extinction Time For Non-Linear Absorption-Diffusion Equations, Jacob B. Goldberg
Finite Extinction Time For Non-Linear Absorption-Diffusion Equations, Jacob B. Goldberg
Theses and Dissertations
In this thesis, we develop a numerical method in order to approximate the solutions of one-dimensional, non-linear absorption-diffusion equations. We test our method for accuracy against a linear diffusion equation with a solution that can be written in closed form. We then test various types of diffusion and absorption terms to determine which ones produce extinction in finite time. We also develop a numerical method to computationally solve diffusion-free equations. We compare the numerical solutions of the one-dimensional, non-linear absorption-diffusion equation and the diffusion-free equation and we find that for the cases tested, the numerical absorption-diffusion solutions are always less …
Comparing Clustering Algorithms For Use With Genomic And Proteomic Data, Rebecca A. Olson
Comparing Clustering Algorithms For Use With Genomic And Proteomic Data, Rebecca A. Olson
Theses and Dissertations
The Human Genome Project and related projects have resulted in the development of a number of new experimental and analytic tools for use in genomic and proteomic research. In the area of toxicogenomics, researchers are concerned with how genes react to exposure to certain chemicals. The United States Air Force is interested in the effect of exposure to mission-essential chemicals. Although military personnel may come into contact with chemicals such as hydrazine, risk assessment is usually very limited. On the genomic level, risk assessment is a multi-stop and multi-disciplinary process. The process begins with an experiment that exposes cells to …
Adaptive Harmonic Balance Method For Unsteady, Nonlinear, One-Dimensional Periodic Flows, Raymond C. Maple
Adaptive Harmonic Balance Method For Unsteady, Nonlinear, One-Dimensional Periodic Flows, Raymond C. Maple
Theses and Dissertations
A new adaptive split-domain harmonic balance computational fluid dynamics (CFD) method is developed to solve highly nonlinear time-periodic flows such as those found in turbomachinery. The basic harmonic balance CFD method transforms an unsteady time-periodic problem into a steady-state problem by assuming a solution in the form of a Fourier series in time. The new method employs a unique multi-domain split-operator solution technique to remove a large-series stability restriction present in previous harmonic balance CFD approaches. In addition, the new method adapts the frequency content to the flow, starting with a small number of Fourier frequencies and augmenting the frequency …
Analysis For Cooperative Behavior Effectiveness Of Autonomous Wide Area Search Munitions, Sang M. Park
Analysis For Cooperative Behavior Effectiveness Of Autonomous Wide Area Search Munitions, Sang M. Park
Theses and Dissertations
The purpose of this study is to investigate how a simulation model can accurately represent the performance of the autonomous wide area search munitions, and to find the effectiveness of the cooperative behavior on the autonomous munitions. Though it does not provide a practical solution for the development of the autonomous wide area search munitions, this research will show some meaningful allocations of the munitions tasks that are applicable to the development of the autonomous munitions. For the first phase, this thesis presents how accurately a simplified simulation model can represent a proposed weapon system by comparing the simulation results …
Visual Execution Analysis For Multiagent Systems, Chong Kil
Visual Execution Analysis For Multiagent Systems, Chong Kil
Theses and Dissertations
Multiagent systems have become increasingly important in developing complex software systems. Multiagent systems introduce collective intelligence and provide benefits such as flexibility, scalability, decentralization, and increased reliability. A software agent is a high-level software abstraction that is capable of performing given tasks in an environment without human intervention. Although multiagent systems provide a convenient and powerful way to organize complex software systems, developing such system is very complicated. To help manage this complexity this research develops a methodology and technique for analyzing, monitoring and troubleshooting multiagent systems execution. This is accomplished by visualizing a multiagent system at multiple levels of …
Efficient And Accurate Computation Of Non-Negative Anisotropic Group Scattering Cross Sections For Discrete Ordinates And Monte Carlo Radiation Transport, David W. Gerts
Theses and Dissertations
A new method for approximating anisotropic, multi-group scatter cross sections for use in discretized and Monte Carlo multi-group neutron transport is presented. The new method eliminates unphysical artifacts such as negative group scatter cross sections and falsely positive cross sections. Additionally, when combined with the discrete elements angular quadrature method, the new cross sections eliminate the lack of angular support in the discrete ordinates quadrature method. The new method generates piecewise-average group-to-group scatter cross sections. The accuracy and efficiency for calculating the discrete elements cross sections has improved by many orders of magnitude compared to DelGrande and Mathews previous implementation. …
Performance Analysis Of A Secure Ieee 802.11b Wireless Network Incorporating Personal Digital Assistants, John L. Camp
Performance Analysis Of A Secure Ieee 802.11b Wireless Network Incorporating Personal Digital Assistants, John L. Camp
Theses and Dissertations
Research results of this thesis indicate very poor performance of a Wireless Local Area Network (WLAN) utilizing PDAs. Network throughput is adversely effected most by VPN implementation and slightly by increased file size. The client distance factor has virtually no effect on the throughput. The impact of each of these factor levels is small when compared to the magnitude of the overall mean throughput (<6%). The average network throughput with the PDA client is much lower than expected (=11,500 bps). This is attributed to several factors with degradation primarily resulting from limitations of the PDA hardware and O/S. Because of the low throughput values achieved (regardless if VPN is on or off), an operational WLAN with PDAs (as tested) is not feasible. Operational use of the network tested would require an in-depth analysis of the type of network traffic and performance required to maintain functionality. To deploy such a system, custom designed Winsock controls would need to be implemented to minimize limitations imposed by the PDA. As PDA technology continues to develop, future hardware and O/S functionality may provide a more robust platform for network communications. The battery life of the PDA and packet battery combination is observed to be about 164 minutes with additional jackets adding about 90 minutes each.
Long Range Forecast Possibilities For X-Band Radar Construction On Shemya, Brian K. Schroeder
Long Range Forecast Possibilities For X-Band Radar Construction On Shemya, Brian K. Schroeder
Theses and Dissertations
Current moisture initialization sources lack the spatial and temporal resolution required for mesoscale moisture forecast accuracy critical for military operations. The Global Positioning System (GPS) satellite constellation provides an opportunity to extract accurate moisture observations based on the refraction of the GPS signal through the troposphere. GPS-derived precipitable water (PW) from two different research areas was independently compared with the Air Force Weather Agency s (AFWA's) MM5 PW model output. Results were concurrent with similar studies comparing GPS-derived PW with numerical weather models. The mean correlation in CONUS was 92.5%, while in Alaska it was 72.8%. Mean model biases were …
The Horizontal Extent Of Lightning Based On Altitude And Atmospheric Temperature, David R. Vollmer
The Horizontal Extent Of Lightning Based On Altitude And Atmospheric Temperature, David R. Vollmer
Theses and Dissertations
Due to multiple factors, including an increase in military operations tempo and the improved resolution of meteorological models, demand for access to customized aviation weather products has increased exponentially. This has given rise to a need for a multi-purpose interactive aviation weather product generation software solution. This software solution must be platform-independent, multiple data source access configurable, robust, extensible or upgradeable, user-friendly, and an improvement over current visualization applications used in the operational military aviation weather community. This thesis determines whether Unidata MetApps meets these criteria. A software reuse and component-based engineering approach was taken in this thesis. Two experimental …
Quantification Of The Effects Of Data Denial And Limitation In Mm5 Initialization On Forecast Accuracy, Robert W. Evans
Quantification Of The Effects Of Data Denial And Limitation In Mm5 Initialization On Forecast Accuracy, Robert W. Evans
Theses and Dissertations
The current hub-and-spoke network in the European Theater is made up of locations built and organized around a Cold War threat. The threat of large-scale attrition warfare seems to have passed, and the threat of multiple, smaller scale contingencies has placed greater demands on the US military's ability to transport equipment and personnel to multiple locations simultaneously. This research effort utilizes a Multiple Objective Linear Programming (MOLP) model to analyze optimal hub locations in USEUCOM. The model used to analyze the network was developed in Microsoft Excel and followed MOLP techniques to determine the trade-offs between the two constructs of …
Gps-Derived Precipitable Water Compared With The Air Force Weather Agency's Mm5 Model Output, Patricia A. Vollmer
Gps-Derived Precipitable Water Compared With The Air Force Weather Agency's Mm5 Model Output, Patricia A. Vollmer
Theses and Dissertations
Lightning poses a threat to aircraft in flight. To mitigate this threat, the U.S. Air Force requested a study of lightning distances. Three-Dimensional lightning data were examined for this study, spanning 1 March 1997 to 31 May 2001 and obtained from the Lightning Detection and Ranging System (LDAR) at the Kennedy Space Center, FL. The LDAR data points were first grouped into lightning flashes and branches using spatial and temporal criteria. Rawinsonde data were vertically interpolated to determine the temperature at the flash source point and each branch end point. The horizontal distance from flash sources to branch end was …
Suitability Of Unidata Metapps For Incorporation In Platform-Independent User-Customized Aviation Weather Products Generation Software, Harmen P. Visser
Suitability Of Unidata Metapps For Incorporation In Platform-Independent User-Customized Aviation Weather Products Generation Software, Harmen P. Visser
Theses and Dissertations
The Air Force Combat Climatology Center (AFCCC) is tasked to provide long-range seasonal forecasts for worldwide locations. Currently, the best long-range temperature forecasts the weather community has are the climatological standard normals. This study creates a stepping-stone into the solution of long-range forecasting by finding a process to predict temperatures better than those using climatological standard normals or simple frequency distributions of occurrences. Northern Hemispheric teleconnection indices and the standardized Southern Oscillation index are statistically compared to three-month summed Heating Degree Days (HDDs) and Cooling Degree Days (CDDs) at 14 U.S. locations. First, linear regression was accomplished. The results showed …
Using An Inductive Learning Algorithm To Improve Antibody Generation In A Single Packet Computer Defense Immune System, Russell J. Aycock
Using An Inductive Learning Algorithm To Improve Antibody Generation In A Single Packet Computer Defense Immune System, Russell J. Aycock
Theses and Dissertations
Coherent optical sources in the mid-infrared region (mid-IR) are important fundamental tools for infrared countermeasures and battlefield remote sensing. Nonlinear optical effects can be applied to convert existing near-IR laser sources to radiate in the mid-IR. This research focused on achieving such a conversion with a quasi-phase matched optical parametric oscillators using orientation-patterned gallium arsenide (OPGaAs), a material that can be quasi-phased matched by periodically reversing the crystal structure during the epitaxial growth process. Although non-linear optical conversion was not ultimately achieved during this research, many valuable lessons were learned from working with this material. This thesis reviews the theory …
Estimation Of Atmospheric Precipitable Water Using The Global Positioning System, David A. Garay
Estimation Of Atmospheric Precipitable Water Using The Global Positioning System, David A. Garay
Theses and Dissertations
This research focuses on using the Global Positioning System (GPS) for atmospheric precipitable water (PW) estimation. Water vapor, measured in terms of PW, plays a crucial role in atmospheric processes and short-term weather forecasting. Traditional methodologies for measuring atmospheric water vapor distributions have known inadequacies, resulting in the motivation to gain good water vapor characterization via GPS. The ability to accurately forecast cloud formation and other weather phenomenon is critical, especially in the case of military operations. Using a network of GPS receivers, it is possible to estimate precipitable water throughout the network region with better accuracy than traditional methods …
Verification Of Mm5 Cloud Microphysics Schemes For East Asia, Dean J. Carter
Verification Of Mm5 Cloud Microphysics Schemes For East Asia, Dean J. Carter
Theses and Dissertations
Using the 3-Dimensional Variational Analysis data assimilation scheme and the (MM5), input observations were denied in three different categories: total, upper air, and surface observation denial. Two control groups were run using all available data as received by AFWA. The main control group used a 6 hours old first guess as a baseline. The data denied test cases and the secondary control group used a 30-hour old first guess because it was not possible to deny data from the first guess. The secondary control group was used to estimate errors resulting from the use of different first guess forecasts between …
An Interactive Decision Support System For Scheduling Fighter Pilot Training, Cuong T. Nguyen
An Interactive Decision Support System For Scheduling Fighter Pilot Training, Cuong T. Nguyen
Theses and Dissertations
The U.S. Air Force is developing Modular Aircraft Support System (MASS) program to replace the current Aerospace Ground Equipment (AGE). AGE supplies electricity, nitrogen, hydraulics and other support equipment to maintenance activities at the flight line. Current AGE makes up one-third of the deployment footprint. AGE is also mostly aircraft specific, and has reliability problems. The MASS alternative focuses on modularity based on a plug-and-play approach. The technological improvements and possible reduction in the footprint make MASS a good alternative. The AF has to determine now, whether MASS can supply similar functionality and decrease the deployment footprint to theater, while …
Portable High-Performance Indexing For Vector Product Format Spatial Databases, Engin Colak
Portable High-Performance Indexing For Vector Product Format Spatial Databases, Engin Colak
Theses and Dissertations
Geo-spatial databases have an overall performance problem because of their complexity and large size. For this reason, many researchers seek new ways to improve the overall performance of geo-spatial databases. Typically, these research efforts are focused on complex indexing structures and query processing methods to capture the relationships between the individual features of fully-functional geo-spatial databases. Visualization applications, such as combat simulators and mission planning tools, suffer from the general performance problems associated with geo-spatial databases. This research focuses on building a high-performance geo-spatial database for visualization applications. The main approach is to simplify the complex data model and to …
Distributed Beacon Requirements For Branch Point Tolerant Laser Beam Compensation In Extended Atmospheric Turbulence, Virgil E. Zetterlind Iii
Distributed Beacon Requirements For Branch Point Tolerant Laser Beam Compensation In Extended Atmospheric Turbulence, Virgil E. Zetterlind Iii
Theses and Dissertations
Branch point tolerant phase reconstructors can vastly improve adaptive optic system performance in extended atmospheric turbulence. This thesis explores the performance bounds of two such reconstructors Goldstein's algorithm and hidden phase. A least squares reconstructor is implemented for comparison. System performance is presented for various scenarios, including correction time-delays, wave-front sensor noise, and extended beacons. These scenarios are of interest for laser communication and directed energy systems such as Airborne Laser. Performance bounds are obtained through wave-optics simulation. The extended beacon propagation geometry approximates the USAF AFRL-DE North Oscura Peak range. Results show that branch point tolerant reconstructors outperform least …
Selecting Salient Features In High Feature To Exemplar Ratio Conditions, Ismail Aslan
Selecting Salient Features In High Feature To Exemplar Ratio Conditions, Ismail Aslan
Theses and Dissertations
A key tenet to the Air Force's vision of Global Vigilance, Reach, and Power is the ability to project power via the use of aerial refueling. Scheduling of limited tanker resources is a major concern for Air Mobility Command (AMC). Currently the Combined Mating and Ranging Planning System (CMARPS) is used to plan aerial refueling operations, however due to the complex nature of the program and the length of time needed to run a scenario, the need for a simple tool that runs in much shorter time is desired. Ant colony algorithms are recently developed heuristics for finding solutions to …
Collisional Dynamics Of Bi2 A(0U+). Ii. State-To-State Rotational Energy Transfer, Robert E. Franklin, Glen P. Perram
Collisional Dynamics Of Bi2 A(0U+). Ii. State-To-State Rotational Energy Transfer, Robert E. Franklin, Glen P. Perram
Faculty Publications
Rotational-to-translational (R–T) energy transfer within v′=1 of the A(0+u) state of Bi2 has been investigated using spectrally resolved, laser induced fluorescence techniques. Spectrally resolved emissions from collisionally populated rotational levels of Bi2(A,v′=1) were observed for helium, neon, and argon collision partners after laser excitation of the high rotational levels J′=171, 201, and 231. Total rotational removal rates from the initially prepared state range from 2.8–8.9×10−10 cm3/molecule s. Collisional population of rotational states with |ΔJ|⩽56 was observed at pressures of 0.09–1.4 Torr. The state-to-state rates are adequately modeled by the energy based statistical power gap …
Investigation Of Cooperative Behavior In Autonomous Wide Search Munitions, Robert E. Dunkel Iii
Investigation Of Cooperative Behavior In Autonomous Wide Search Munitions, Robert E. Dunkel Iii
Theses and Dissertations
The purpose of this research is to investigate the effectiveness of wide-area search munitions in various scenarios using different cooperative behavior algorithms. The general scenario involves multiple autonomous munitions searching for an unknown number of targets of different priority in unknown locations. Three cooperative behavior algorithms are used in each scenario: no cooperation, cooperative attack only, and cooperative classification and attack. In the cooperative cases, the munitions allocate tasks on-line as a group, using linear programming techniques to determine the optimum allocation. Each munition provides inputs to the task allocation routine in the form of probabilities of successfully being able …
Fabrication And Cold-Flow Testing Of Subscale Space-Based Laser Geometry, Scott E. Bergren
Fabrication And Cold-Flow Testing Of Subscale Space-Based Laser Geometry, Scott E. Bergren
Theses and Dissertations
The objectives of this research were to build a facility that could simulate the expected fluid flow properties in the conceptual Space Based Laser Integrated Flight Experiment (SBL IFX) gas dynamic laser using cold-flow, and to investigate the performance of the model. A 1/5th scale model was fabricated and mated to a blow-down/vacuum wind tunnel. Using rapid data acquisition and schlieren photography the diffuser was determined to initially produce similar fluid flow to the SBL IFX, but rapidly became subsonic due to a transient normal shock wave formed when the wind tunnel was started.
A Visual Meta-Language For Generic Modeling, Hakan Canli
A Visual Meta-Language For Generic Modeling, Hakan Canli
Theses and Dissertations
This research examines the usefulness of a visual meta-language (VLGM Visual Language for Generic Modeling) developed for the specification of components and relations in a modeling domain. The language is designed to allow software tools to interpret specifications and automatically provide modeling environments. VLGM makes use of the object-orientated software engineering methodology. It defines four types of special classes and three types of relations between them. Data types and primitive types are allocated with several attributes to provide restrictions and enable consistency checks over models. As part of this research a software tool was designed. The tool provides a workspace …
A Comparison Of Modeling Approaches In Simulating Chlorinated Ethene Removal In A Constructed Wetland By A Microbial Consortia, Jason S. Campbell
A Comparison Of Modeling Approaches In Simulating Chlorinated Ethene Removal In A Constructed Wetland By A Microbial Consortia, Jason S. Campbell
Theses and Dissertations
The purpose of this study is to compare different approaches to modeling the reductive dechlorination of chlorinated ethenes in the anaerobic region of an upward flow constructed wetland by microbial consortia. A controlled simulation experiment that compares three different approaches to modeling the degradation of chlorinated ethenes in wetland environments is conducted and investigates how each of the modeling approaches affect simulation results. Concepts like microbial growth in the form of a biofilm and spatially varying contaminant concentrations bring the validity of the CSTR assumption into question. These concepts are incorporated into the different modeling approaches to evaluate the CSTR …
Chromate Content Bias Versus Overspray Particle Size In Three Aircraft Primer Paints, Brian S. Rhodes
Chromate Content Bias Versus Overspray Particle Size In Three Aircraft Primer Paints, Brian S. Rhodes
Theses and Dissertations
The United States Air Force relies on the corrosion inhibiting properties of chromate-containing primer paints to protect the aluminum skin of its aircraft. Hexavalent chromium (Cr6+) the ingredient responsible for the corrosion inhibiting characteristics of these primers is a known human carcinogen. The concentration of Cr6+ in different particle sizes of paint overspray is important to understand health implications to painters as well as filtration efficiency. Previous research indicates disproportionately less Cr6+ content in smaller particles collected in the overspray of solvent-based epoxy-polyamide paint primers (MIL-P-2377G). This research explores the possibility of a particle size bias …
Fabrication Techniques For Micro-Optical Device Arrays, Ryan D. Conk
Fabrication Techniques For Micro-Optical Device Arrays, Ryan D. Conk
Theses and Dissertations
Micro-optical devices are vital components of conventional military data storage, sensor, and communication systems. Two types of micro-optical device arrays exist: individually addressable and matrix addressable. The matrix addressable array has a drastically reduced number of metal lines and can potentially be fabricated into large, dense (over 1k elements) arrays. Such arrays are expected to enable the development of extremely high bandwidth optical interconnect systems for future military applications including optical computing and short-haul fiber optical communication systems. I investigate new fabrication techniques for the assembly of dense matrix-addressed arrays of micro-optical devices such as vertical-cavity surface-emitting lasers. Using a …
Verification And Comparison Of Polar Mm5 And Afwa Mm5 Forecasts Over Alaska, William E. Courtemanche
Verification And Comparison Of Polar Mm5 And Afwa Mm5 Forecasts Over Alaska, William E. Courtemanche
Theses and Dissertations
This research compares biases of the Reisner Mixed-Phase Explicit Moisture Microphysics graupel and non-granpel schemes to determine if including graupel and riming processes within the Fifth Generation Mesoscale Model (MM5) will lead to improved forecasts of winter precipitation for Korea and Japan. MM5 forecasts were generated every 12 hours for a 20 days case period from January 1998. Model derived meteorological fields were interpolated to the station coordinates of four verification sites within the East Asian domain and radiosonde observations were used to compare the differences between the average temperature and water vapor errors of the two cloud microphysics schemes. …