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Theory Of Effectiveness Measurement, Richard K. Bullock
Theory Of Effectiveness Measurement, Richard K. Bullock
Theses and Dissertations
Effectiveness measures provide decision makers feedback on the impact of deliberate actions and affect critical issues such as allocation of scarce resources, as well as whether to maintain or change existing strategy. Currently, however, there is no formal foundation for formulating effectiveness measures. This research presents a new framework for effectiveness measurement from both a theoretical and practical view. First, accepted effects-based principles, as well as fundamental measurement concepts are combined into a general, domain independent, effectiveness measurement methodology. This is accomplished by defining effectiveness measurement as the difference, or conceptual distance from a given system state to some reference …
Optimizing The Replication Of Multi-Quality Web Applications Using Aco And Wolf, Judson C. Dressler
Optimizing The Replication Of Multi-Quality Web Applications Using Aco And Wolf, Judson C. Dressler
Theses and Dissertations
This thesis presents the adaptation of Ant Colony Optimization to a new NP-hard problem involving the replication of multi-quality database-driven web applications (DAs) by a large application service provider (ASP). The ASP must assign DA replicas to its network of heterogeneous servers so that user demand is satisfied and replica update loads are minimized. The algorithm proposed, AntDA, for solving this problem is novel in several respects: ants traverse a bipartite graph in both directions as they construct solutions, pheromone is used for traversing from one side of the bipartite graph to the other and back again, heuristic edge values …
A New Application Of The Channel Packet Method For Low Energy 1-D Elastic Scattering, Clint M. Zeringue
A New Application Of The Channel Packet Method For Low Energy 1-D Elastic Scattering, Clint M. Zeringue
Theses and Dissertations
An algorithm is presented which uses the channel packet method (CPM) to simulate low-energy, wave-packet propagation and compute S-matrix elements. A four-by-four matrix containing the momentum, expansion coefficients of the reactants and products is introduced to account for initial and final states having both positive and negative momentum. The approach does not consider scattering from one side or the other, rather it considers both incoming and outgoing wave packets from the left and right simultaneously. Therefore, during one simulation all four S-matrix elements, and elements, S+k,-K, S-k, +k, S+k, +k and S-k,-k are computed. …
New Tracking Filter Algorithm Using Input Parameter Estimation, Corey M. Broussard
New Tracking Filter Algorithm Using Input Parameter Estimation, Corey M. Broussard
Theses and Dissertations
A new method for the design of tracking filters for maneuvering targets, based on kinematic models and input signals estimation, is developed. The input signal's level, u is considered a continuous variable and consequently the input estimation problem is posed as a purely parameter estimation problem. Moreover, the application of the new tracking filter algorithm is not contingent on distinguishing maneuvering and non-maneuvering targets, and does not require the detection of maneuver onset. The filter will automatically detect the onset of a maneuver. Furthermore, an estimate of the target's acceleration is also obtained with reasonable precision. This opens the door …
Statistical Approach To Background Subtraction For Production Of High-Quality Silhouettes For Human Gait Recognition, Jennifer J. Samler
Statistical Approach To Background Subtraction For Production Of High-Quality Silhouettes For Human Gait Recognition, Jennifer J. Samler
Theses and Dissertations
This thesis uses a background subtraction to produce high-quality silhouettes for use in human identification by human gait recognition, an identification method which does not require contact with an individual and which can be done from a distance. A statistical method which reduces the noise level is employed resulting in cleaner silhouettes which facilitate identification. The thesis starts with gathering video data of individuals walking normally across a background scene. From there the video is converted into a sequence of images that are stored as joint photographic experts group (jpeg) files. The background is subtracted from each image using a …
Fast Scene Based Nonuniformity Correction With Minimal Temporal Latency, Christopher A. Rice
Fast Scene Based Nonuniformity Correction With Minimal Temporal Latency, Christopher A. Rice
Theses and Dissertations
The focus of this research was to derive a new algorithm for correction of gain nonuniformities in LIDAR focal plane arrays using as few frames as possible. Because of the current low production rate of LIDAR focal plane arrays there is a natural tendency for extreme nonuniformities to exist on a pixel by pixel basis as the manufacturing technique has not yet been perfected. Generally, nonuniformity correction techniques require a large number of frames and/or have obscure requirements on the translational shifts in the input image frames. This thesis presents a solution for finding multiplicative nonuniformities that exist in a …
Development And Testing Of A High-Speed Real-Time Kinematic Precise Dgps Positioning System Between Two Aircraft, Christopher J. Spinelli
Development And Testing Of A High-Speed Real-Time Kinematic Precise Dgps Positioning System Between Two Aircraft, Christopher J. Spinelli
Theses and Dissertations
This research involves the design, implementation, and testing of a high-speed, real-time kinematic, precise differential GPS positioning system for use in airborne applications such as automated aerial-refueling and close formation flying. Although many of the current ambiguity resolution techniques use the residuals from the least squares position estimation to determine the true ambiguity set, this thesis presents a novel approach to the ambiguity resolution problem, called the minimum indicator. Instead of assuming the ambiguity set with the lowest residuals is the true set, other special characteristics of the residuals are examined. This increases the confidence that the algorithm has selected …
Existence Of Large Solutions To Semilinear Elliptic Equations With Multiple Terms, David N. Smith
Existence Of Large Solutions To Semilinear Elliptic Equations With Multiple Terms, David N. Smith
Theses and Dissertations
We consider the semilinear elliptic equation Δu = p(x)uα + q(x)uβ on a domain Ω ⊆ Rn, n ≥ 3, where p and q are nonnegative continuous functions with the property that each of their zeroes is contained in a bounded domain Ωp or Ωq, respectively in Ω such that p is positive on the boundary of Ωp and q is positive on the boundary of Ωq. For Ω bounded, we show that there exists a nonnegative solution u such that u(x) → ∞ as x → ∂Ω if …
Development Of A Methodology For Customizing Insider Threat Auditing On A Microsoft Windows Xp® Operating System, Terry E. Levoy
Development Of A Methodology For Customizing Insider Threat Auditing On A Microsoft Windows Xp® Operating System, Terry E. Levoy
Theses and Dissertations
Most organizations are aware that threats from trusted insiders pose a great risk to their organization and are very difficult to protect against. Auditing is recognized as an effective technique to detect malicious insider activities. However, current auditing methods are typically applied with a one-size-fits-all approach and may not be an appropriate mitigation strategy, especially towards insider threats. This research develops a 4-step methodology for designing a customized auditing template for a Microsoft Windows XP operating system. Two tailoring methods are presented which evaluate both by category and by configuration. Also developed are various metrics and weighting factors as a …
Robot Localization Using Visual Image Mapping, Carrie D. Crews
Robot Localization Using Visual Image Mapping, Carrie D. Crews
Theses and Dissertations
One critical step in providing the Air Force the capability to explore unknown environments is for an autonomous agent to be able to determine its location. The calculation of the robot's pose is an optimization problem making use of the robot's internal navigation sensors and data fusion of range sensor readings to find the most likely pose. This data fusion process requires the simultaneous generation of a map which the autonomous vehicle can then use to avoid obstacles, communicate with other agents in the same environment, and locate targets. Our solution entails mounting a Class 1 laser to an ERS-7 …
Evaluation Of Microbial Diversity In Wetland Through Polymerase Chain Reaction (Pcr) And Restriction Fragment Length Polymorphism (Rflp), Gregory K. Joseph
Evaluation Of Microbial Diversity In Wetland Through Polymerase Chain Reaction (Pcr) And Restriction Fragment Length Polymorphism (Rflp), Gregory K. Joseph
Theses and Dissertations
The diversity of microbial communities in wetlands has not been fully measured. These communities may offer tools to naturally remediate sites polluted with chlorinated compounds. Polmerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP) are genomic techniques that are capable of rapidly characterizing bacteria communities and can provide valuable information about the diversity of microbial communities.
Mitigating Insider Threat Using Human Behavior Influence Models, Anthony J. Puleo
Mitigating Insider Threat Using Human Behavior Influence Models, Anthony J. Puleo
Theses and Dissertations
Insider threat is rapidly becoming the largest information security problem that organizations face. With large numbers of personnel having access to internal systems, it is becoming increasingly difficult to protect organizations from malicious insiders. The typical methods of mitigating insider threat are simply not working, primarily because this threat is a people problem, and most mitigation strategies are geared towards profiling and anomaly detection, which are problematic at best. As a result, a new type of model is proposed in this thesis, one that incorporates risk management with human behavioral science. The new risk-based model focuses on observable influences that …
Molecular Characterization Of Wetland Soil Bacterial Community In Constructed Mesocosms, Ethan C. Bishop
Molecular Characterization Of Wetland Soil Bacterial Community In Constructed Mesocosms, Ethan C. Bishop
Theses and Dissertations
The use of wetlands to effectively remediate aquifers contaminated with chlorinated solvents is an emerging technique, which shows high promise. In order to better understand this process and test its legitimacy, a treatment wetland was constructed at Wright-Patterson AFB, Dayton, Ohio and, in a joint effort with Wright State University (WSU), has previously shown the effective removal of PCE. The purpose of this research was to characterize the soil bacterial community, pre-PCE injection, among three wetland plant species from the sedge family (Cyperaceae) within constructed wetland mesocosms and to identify any bacterial dominance. Carex comosa, Scirpus atrovirens, and Eleocharis erythropoda …
Characterizing A Co-Flow Nozzle For Use In A Filtered Rayleigh Scattering System, David S. Miceli
Characterizing A Co-Flow Nozzle For Use In A Filtered Rayleigh Scattering System, David S. Miceli
Theses and Dissertations
Research was conducted on the flow field exiting a co-annular flow nozzle for use in filtered Rayleigh scattering flow visualizations. More specifically, the flow visualizations were of the flow field exiting a coflow nozzle and illuminated by a tunable, nominal 4.2 watt narrow line width Argon laser operating at 514.5nm. ND:YAG lasers are typically used in this application, but some of the properties of a tunable Argon laser make it an attractive alternative. Before generating flow visualizations, the coflow nozzle was characterized both experimentally and computationally. Due to a flow asymmetry in the outer annulus flow field, the nozzle was …
Afit Uav Swarm Mission Planning And Simulation System, James N. Slear
Afit Uav Swarm Mission Planning And Simulation System, James N. Slear
Theses and Dissertations
The purpose of this research is to design and implement a comprehensive mission planning system for swarms of autonomous aerial vehicles. The system integrates several problem domains including path planning, vehicle routing, and swarm behavior. The developed system consists of a parallel, multi-objective evolutionary algorithm-based path planner, a genetic algorithm-based vehicle router, and a parallel UAV swarm simulator. Each of the system's three primary components are developed on AFIT's Beowulf parallel computer clusters. Novel aspects of this research include: integrating terrain following technology into a swarm model as a means of detection avoidance, combining practical problems of path planning and …
Development And Validation Of Reentry Simulation Using Matlab, Robert E. Jameson Jr.
Development And Validation Of Reentry Simulation Using Matlab, Robert E. Jameson Jr.
Theses and Dissertations
This research effort develops a program using MATLAB to solve the equations of motion for atmospheric reentry and analyzes the validity of the program for use as a tool to expeditiously predict reentry profiles. The reentry vehicle is modeled as a point mass with constant aerodynamic properties as defined by the user. The equations of motion for reentry are based on the two-body problem. The atmosphere is modeled as a single layer exponentially decreasing in density. The MATLAB program has the ability to derive the initial trajectory conditions from the position and velocity relative to the rotating surface of the …
Development Of A Malicious Insider Composite Vulnerability Assessment Methodology, William H. King
Development Of A Malicious Insider Composite Vulnerability Assessment Methodology, William H. King
Theses and Dissertations
Trusted employees pose a major threat to information systems. Despite advances in prevention, detection, and response techniques, the number of malicious insider incidents and their associated costs have yet to decline. There are very few vulnerability and impact models capable of providing information owners with the ability to comprehensively assess the effectiveness an organization's malicious insider mitigation strategies. This research uses a multi-dimensional approach: content analysis, attack tree framework, and an intent driven taxonomy model are used to develop a malicious insider Decision Support System (DSS) tool. The DSS tool's utility and applicability is demonstrated using a notional example. This …
Small Sample Confidence Intervals In Log Space Back-Transformed From Normal Space, Jason E. Tisdel
Small Sample Confidence Intervals In Log Space Back-Transformed From Normal Space, Jason E. Tisdel
Theses and Dissertations
The logarithmic transformation is commonly applied to a lognormal data set to improve symmetry, homoscedasticity, and linearity. Simple to implement and easy to understand, the logarithm function transforms the original data to closely resemble a normal distribution. Analysis in the normal space provides point estimates and confidence intervals, but transformation back to the original space using the naive approach yields confidence intervals of impractical width. The naive approach offers results that are often inadequate for practical purpose. We present an alternative approach that provides improved results in the form of decreased interval width, increased confidence level, or both. Our alternative …
An Analysis Of Nonlinear Elastic Deformations For A Homogeneous Beam At Varying Tip Loads And Pitch Angles, Robert J. Mcgraw
An Analysis Of Nonlinear Elastic Deformations For A Homogeneous Beam At Varying Tip Loads And Pitch Angles, Robert J. Mcgraw
Theses and Dissertations
The Princeton beam experiments of 1975 were performed in hopes of producing viable data for beam nonlinear elastic deformation models in hopes of improving helicopter main beam designs. The recorded data, specifically for homogeneous beams of 7075 aluminum, have been referenced as a baseline for the past thirty years to validate numerous computer models and theories in an effort to build beams capable of withstanding aeroelastic, static, and dynamic loading. The purpose of this study is to improve upon the data recorded in 1975 using newer technologies including a laser distance meter, digital inclinometer, and three-dimensional traverse to test X-axis, …
An Experimental Study Of A Pulsed Dc Plasma Flow Control Actuator, Jennifer D. Wall
An Experimental Study Of A Pulsed Dc Plasma Flow Control Actuator, Jennifer D. Wall
Theses and Dissertations
An experiment on the effects of a pulsed DC plasma actuator on a separated flow in a low speed wind tunnel was conducted. The actuator consisted of two asymmetric copper electrodes oriented normal to the flow separated by a dielectric barrier and mounted on a flat plate in the center of the tunnel. A contoured insert was constructed and used to create an adverse pressure gradient in the test section comparable to a Pak-B low pressure turbine blade distribution. Suction was applied from the upper wall to induce separation along the flat plate over the electrodes. The DC power supply …
Mitigating Tcp Degradation Over Intermittent Link Failures Using Intermediate Buffers, M. Brent Reynolds
Mitigating Tcp Degradation Over Intermittent Link Failures Using Intermediate Buffers, M. Brent Reynolds
Theses and Dissertations
This thesis addresses the improvement of data transmission performance in a challenged network. It is well known that the popular Transmission Control Protocol degrades in environments where one or more of the links along the route is intermittently available. To avoid this degradation, this thesis proposes placing at least one node along the path of transmission to buffer and retransmit as needed to overcome the intermittent link. In the four-node, three-link testbed under particular conditions, file transmission time was reduced 20 fold in the case of an intermittent second link when the second node strategically buffers for retransmission opportunity.
Performance-Metric Driven Atmospheric Compensation For Robust Free-Space Laser Communication, Peter N. Crabtree
Performance-Metric Driven Atmospheric Compensation For Robust Free-Space Laser Communication, Peter N. Crabtree
Theses and Dissertations
The effect of turbulence on laser propagation is a significant challenge to current electro-optical systems. While atmospheric compensation techniques in space object imaging and high-energy laser weapons have been thoroughly investigated, optimizing these techniques for Laser Communication (LaserCom) has not been examined to the same degree. Average Strehl ratio is the typical design metric for current atmospheric compensation systems. However, fade probability is the relevant metric for LaserCom. This difference motivated the investigation into metric-driven atmospheric compensation. Metric-based tracking techniques for fade mitigation is the first major focus of this research. In a moderate range air-to-air scenario, focal plane spot …
An Interactive Relaxation Approach For Anomaly Detection And Preventive Measures In Computer Networks, Garrick A. Bell
An Interactive Relaxation Approach For Anomaly Detection And Preventive Measures In Computer Networks, Garrick A. Bell
Theses and Dissertations
It is proposed to develop a framework of detecting and analyzing small and widespread changes in specific dynamic characteristics of several nodes. The characteristics are locally measured at each node in a large network of computers and analyzed using a computational paradigm known as the Relaxation technique. The goal is to be able to detect the onset of a worm or virus as it originates, spreads-out, attacks and disables the entire network. Currently, selective disabling of one or more features across an entire subnet, e.g. firewalls, provides limited security and keeps us from designing high performance net-centric systems. The most …
Factors Impacting Key Management Effectiveness In Secured Wireless Networks, Yongjoo Shin
Factors Impacting Key Management Effectiveness In Secured Wireless Networks, Yongjoo Shin
Theses and Dissertations
The use of a Public Key Infrastructure (PKI) offers a cryptographic solution that can overcome many, but not all, of the MANET security problems. One of the most critical aspects of a PKI system is how well it implements Key Management. Key Management deals with key generation, key storage, key distribution, key updating, key revocation, and certificate service in accordance with security policies over the lifecycle of the cryptography. The approach supported by traditional PKI works well in fixed wired networks, but it may not appropriate for MANET due to the lack of fixed infrastructure to support the PKI. This …
Backward Amplification And Beam Cleanup Of A Raman Fiber Laser Oscillator Using A Multi-Mode Graded Index Fiber Amplifier, Jesse D. S. Morgan Iii
Backward Amplification And Beam Cleanup Of A Raman Fiber Laser Oscillator Using A Multi-Mode Graded Index Fiber Amplifier, Jesse D. S. Morgan Iii
Theses and Dissertations
This thesis tested a CW fiber-based Raman amplifier implemented in a backward pumped geometry. To create a seed for the amplifier, a CW Nd:YAG laser operating at 1.064µm was used to pump a 50µm multimode graded index fiber using fiber Bragg gratings to create a Raman Fiber Laser (RFL) Oscillator with a Stokes beam at 1.116µm. The Stokes beam was then used to seed two lengths, 5.3km and 2.5km, of 50µm multimode graded index fiber. The fiber amplifier was pumped by a second CW Nd:YAG laser in the backward geometry. Spectral data taken for both fibers indicated that the backward …
Investigation Of Copper Contamination And Corrosion Scale Mineralogy In Aging Drink Water Distributions Systems, Nadja F. Turek
Investigation Of Copper Contamination And Corrosion Scale Mineralogy In Aging Drink Water Distributions Systems, Nadja F. Turek
Theses and Dissertations
Research has shown higher levels of copper appear in drinking water conveyed through relatively new copper piping systems; older piping systems typically deliver lower copper levels in their drinking water. This research contributes field data from a real drinking water distribution system, providing a better understanding of this phenomenon, as it relates to treatment considerations and compliance with the Lead and Copper Rule. Copper pipes and copper levels were sampled from drinking water taps of 16 buildings with pipes ranging in age from less than 1 to 48 years. Water samples from each building were collected before and following a …
Comparison Of Climatological Optical Turbulence Profiles To Standard, Statistical And Numerical Models Using Heleeos, Liesebet E. Gravley
Comparison Of Climatological Optical Turbulence Profiles To Standard, Statistical And Numerical Models Using Heleeos, Liesebet E. Gravley
Theses and Dissertations
Optical turbulence within earth’s atmosphere plays a significant role in electromagnetic radiation propagation from a high energy laser. The index of refraction structure constant, Cn2, characterizes turbulent spatial fluctuations due to temperature gradients. These changes in the index of refraction affect the intensity of the laser wave front on its intended target. It is important to characterize this parameter throughout the atmosphere, the boundary layer and above, for its applications regarding the Airborne Laser (ABL) and the Advanced Tactical Laser (ATL). There are several ways to obtain values of optical turbulence, including standard and statistical models, physically-based numerical models, and …
Assessing The Potential For Improved Scramjet Performance Through Application Of Electromagnetic Flow Control, Martin F. Lindsey
Assessing The Potential For Improved Scramjet Performance Through Application Of Electromagnetic Flow Control, Martin F. Lindsey
Theses and Dissertations
Hypersonic flight using scramjet propulsion bridges the gap between turbojets and rockets. Recent efforts focus on magnetogasdynamic (MGD) flow control to mitigate the problems of high thermomechanical loads and low efficiencies associated with scramjets. This research is the first flight-scale, three-dimensional computational analysis of a realistic scramjet to assess how MGD flow control improves scramjet performance. Developing a quasi-one dimensional design tool culminated in the first open source scramjet geometry. This geometry was tested with the Air Force Research Laboratory's electromagnetic computational code. To increase fidelity, an algorithm was developed to incorporate thermochemistry, resulting in the only open-source model of …
Efficient And Accurate Computation Of Elastic Cross Sections In The Single-Level Breit-Wigner Resonance Region, Edward L. Hobbs
Efficient And Accurate Computation Of Elastic Cross Sections In The Single-Level Breit-Wigner Resonance Region, Edward L. Hobbs
Theses and Dissertations
The use of piecewise cubic Hermite polynomials to approximate resonance region cross sections provides a means to accomplish the same task with increased accuracy and fewer points that require exact cross section calculation. Once the derivative of the cross section formula is derived and the interpolating cubic is appropriately shifted and scaled for numerical stability, use of the piecewise cubic Hermite polynomial is easily inserted into computer codes that depend on cross section calculation in the resonance energy region.
Development Of A Three-Dimensional Air Blast Propagation Model Based Upon The Weighted Average Flux Method, Stephen R. Mchale
Development Of A Three-Dimensional Air Blast Propagation Model Based Upon The Weighted Average Flux Method, Stephen R. Mchale
Theses and Dissertations
Accurate numerical modeling of complex, multi-dimensional shock propagation is needed for many Department of Defense applications. A three-dimensional code, based upon E.F. Toro's weighted average flux (WAF) method has been developed, tested, and validated. Code development begins with the introduction and application of all techniques in a single dimension. First-order accuracy is achieved via Godunov's scheme using an exact Riemann solver. Adaptive techniques, which employ approximate solutions, are implemented to improve computational efficiency. The WAF method produces second-order accurate solutions, but introduces spurious oscillations near shocks and contact discontinuities. Total variation diminishing (TVD) flux and weight limiting schemes are added …