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Information Management Principles Applied To The Ballistic Missile Defense System, John M. Koehler Ii
Information Management Principles Applied To The Ballistic Missile Defense System, John M. Koehler Ii
Theses and Dissertations
Information systems (IS) have evolved over the last 50 plus years from individual components with single functionality to grand architectures that integrate multiple individual business functions into global organizational enterprises. Similarly several military systems with the single mission of missile defense have evolved in service stovepipes, and are now being integrated into a national and global missile defense architecture. The Missile Defense Agency (MDA) is currently tasked with developing an integrated Ballistic Missile Defense System (BMDS) capable of defending against all ranges of ballistic missiles in all phases of flight in defense of the homeland, our deployed forces, and our …
Heuristically Driven Search Methods For Topology Control In Directional Wireless Hybrid Network, Roger L. Garner
Heuristically Driven Search Methods For Topology Control In Directional Wireless Hybrid Network, Roger L. Garner
Theses and Dissertations
Information and Networked Communications play a vital role in the everyday operations of the United States Armed Forces. This research establishes a comparative analysis of the unique network characteristics and requirements introduced by the Topology Control Problem (also known as the Network Design Problem). Previous research has focused on the development of Mixed-Integer Linear Program (MILP) formulations, simple heuristics, and Genetic Algorithm (GA) strategies for solving this problem. Principal concerns with these techniques include runtime and solution quality. To reduce runtime, new strategies have been developed based on the concept of flow networks using the novel combination of three well-known …
An Artificial Immune System-Inspired Multiobjective Evolutionary Algorithm With Application To The Detection Of Distributed Computer Network Intrusions, Charles R. Haag
An Artificial Immune System-Inspired Multiobjective Evolutionary Algorithm With Application To The Detection Of Distributed Computer Network Intrusions, Charles R. Haag
Theses and Dissertations
Today's predominantly-employed signature-based intrusion detection systems are reactive in nature and storage-limited. Their operation depends upon catching an instance of an intrusion or virus after a potentially successful attack, performing post-mortem analysis on that instance and encoding it into a signature that is stored in its anomaly database. The time required to perform these tasks provides a window of vulnerability to DoD computer systems. Further, because of the current maximum size of an Internet Protocol-based message, the database would have to be able to maintain 25665535 possible signature combinations. In order to tighten this response cycle within storage constraints, …
Biological Cell Identification By Integrating Micro-Fluidics, Electrical Impedance Spectroscopy And Stochastic Estimation, Karl R. Schwenn
Biological Cell Identification By Integrating Micro-Fluidics, Electrical Impedance Spectroscopy And Stochastic Estimation, Karl R. Schwenn
Theses and Dissertations
The integration of micro-fluidics, electrical impedance spectroscopy and stochastic estimation will lead to a device with enhanced detection capabilities. The goal of this thesis was to build a micro-fluidic electrical impedance measurement device that can be used in combination with a stochastic estimator to accurately identify living cells. A microdevice capable of making impedance measurements on individual living cells was designed and built using a series of standard microelectronic fabrication techniques. A microchannel was patterned in SU-8 photoresist between two gold microelectrodes on a two inch Pyrex 7740 wafer. The design process, the fabrication techniques for the microchannel, the fluid …
2006 Annual Report Of The Graduate School Of Engineering And Management, Air Force Institute Of Technology, Office Of Research And Sponsored Programs, Graduate School Of Engineering And Management, Afit
2006 Annual Report Of The Graduate School Of Engineering And Management, Air Force Institute Of Technology, Office Of Research And Sponsored Programs, Graduate School Of Engineering And Management, Afit
AFIT Documents
The Graduate School's Annual Report highlights research focus areas, new academic programs, faculty accomplishments and news, and provides top-level sponsor-funded research data and information.
Modeling, Simulation, And Estimation Of Optical Turbulence, Byron P. Formwalt
Modeling, Simulation, And Estimation Of Optical Turbulence, Byron P. Formwalt
Theses and Dissertations
This dissertation documents three new contributions to simulation and modeling of optical turbulence. The first contribution is the formalization, optimization, and validation of a modeling technique called successively conditioned rendering (SCR). The SCR technique is empirically validated by comparing the statistical error of random phase screens generated with the technique. The second contribution is the derivation of the covariance delineation theorem, which provides theoretical bounds on the error associated with SCR. It is shown empirically that the theoretical bound may be used to predict relative algorithm performance. Therefore, the covariance delineation theorem is a powerful tool for optimizing SCR algorithms. …
Sampled-Data Kalman Filtering And Multiple Model Adaptive Estimation For Infinite-Dimensional Continuous-Time Systems, Scott A. Sallberg
Sampled-Data Kalman Filtering And Multiple Model Adaptive Estimation For Infinite-Dimensional Continuous-Time Systems, Scott A. Sallberg
Theses and Dissertations
Kalman filtering and multiple model adaptive estimation (MMAE) methods have been applied by researchers in several engineering disciplines to a multitude of problems featuring a linear (or mildly nonlinear) model based on finite-dimensional differential (or difference) equations perturbed by random inputs. However, many real-world systems are more naturally modeled using an infinite-dimensional continuous-time linear systems model, such as those most naturally modeled as partial differential equations or time-delayed differential equations along with a possibly infinite-dimensional measurement model. The Kalman filtering technique was extended to encompass infinite-dimensional continuous-time systems with sampled-data measurements and a technique to approximate an infinite-dimensional continuous-time system …
Dynamic Response Of A Collidant Impacting A Low Pressure Airbag, Peter A. Dreher
Dynamic Response Of A Collidant Impacting A Low Pressure Airbag, Peter A. Dreher
Theses and Dissertations
There are many uses of low pressure airbags, both military and commercial. Many of these applications have been hampered by inadequate and inaccurate modeling tools. This dissertation contains the derivation of a four degree-of-freedom system of differential equations from physical laws of mass and energy conservation, force equilibrium, and the Ideal Gas Law. Kinematic equations were derived to model a cylindrical airbag as a single control volume impacted by a parallelepiped collidant. An efficient numerical procedure was devised to solve the simplified system of equations in a manner amenable to discovering design trends. The largest public airbag experiment, both in …
Predicting Argentine Jet Fuel Prices, Juan A. Salaverry
Predicting Argentine Jet Fuel Prices, Juan A. Salaverry
Theses and Dissertations
Oil distillates are considered important elements to accomplish the missions of the Argentine Air Force (AAF). Of all oil products consumed by the AAF, jet fuel is the resource with highest demand and at the end of the day the most expensive support item procured by the Argentine Air Force. Accurate predictions of Argentine jet fuel prices are necessary to improve AAF financial and logistics planning. This thesis presents a systematic, statistical regression approach to forecast Argentine jet fuel prices. The application of this methodology has allowed us to obtain a very useful model that utilizes information available on the …
Diffusion Of Innovation: Factors Promoting Interest In Solar Photovoltaic Generation Systems Within Air Force Installations, Daniel Diaz Jr.
Diffusion Of Innovation: Factors Promoting Interest In Solar Photovoltaic Generation Systems Within Air Force Installations, Daniel Diaz Jr.
Theses and Dissertations
The purpose of this research was to identify factors which promote interest in solar photovoltaic generation systems for facility use within the United States Air Force. The construct model was developed based on past literature on Diffusion of Innovation Theory. The model comprised of measures defined as motivation, knowledge, experience, and familiarity as well as contextual variables. These measures were then used to determine whether any significant association existed between the measures and the overall dependent variable, interest. A phone interview was conducted on Air Force energy managers located within the continental U.S. The methods of correlation and regression analysis …
Predicting The Effects Of Longitudinal Variables On Cost Schedule Performance, James D. Foreman
Predicting The Effects Of Longitudinal Variables On Cost Schedule Performance, James D. Foreman
Theses and Dissertations
Determining accurate cost and schedule is a crucial step to planning acquisition expenditures but history has shown that estimates are routinely low. Several researchers have attempted to forecast cost and schedule growth; we pick up this stream of research with a new approach. Our data collection and analysis focused on bringing in new data sources and added longitudinal variables to account for changes that took place over time. We assessed cost and schedule parameters for 37 major acquisition programs between Milestones II and III, resulting in 172 input variables and 5 regression models, 2 for schedule slippage and 3 for …
Surrogate Strategies For Computationally Expensive Optimization Problems With Cpu-Time Correlated Functions, Raymond Magallanez Jr.
Surrogate Strategies For Computationally Expensive Optimization Problems With Cpu-Time Correlated Functions, Raymond Magallanez Jr.
Theses and Dissertations
This research focuses on numerically solving a class of computationally expensive optimization problems that possesses a unique characteristic: as the optimal solution is approached, the computational time required to compute an objective function value decreases. This is motivated by an application in which each objective function evaluation requires both a numerical fluid dynamics simulation and an image registration and comparison process. The goal is to find the parameters of a predetermined image by comparing the flow dynamics from the numerical simulation and the predetermined image through the image comparison process. The generalized pattern search and mesh adaptive direct search methods …
Quantifying Non-Equilibrium In Hypersonic Flows Using Entropy Generation, Ryan W. Carr
Quantifying Non-Equilibrium In Hypersonic Flows Using Entropy Generation, Ryan W. Carr
Theses and Dissertations
The constitutive relations traditionally used for finding shear stress and heat flux in a fluid become invalid in non-equilibrium flow. Their derivation from kinetic theory only demonstrates they are valid only for small deviations from equilibrium. Because it is fundamentally linked to non-equilibrium, entropy generation is used to investigate the limits of the continuum constitutive relations. However, the continuum equations are inherently limited to near equilibrium conditions due to the constitutive relations; thus kinetic theory must be used as a basis for comparison. Direct Simulation Monte Carlo (DSMC), a particle method alternative to continuum methods, is based on kinetic theory …
The Effects Of Microstructure On Fretting Fatigue Behavior Of Nickel Alloy In-100, Erik C. Saladin
The Effects Of Microstructure On Fretting Fatigue Behavior Of Nickel Alloy In-100, Erik C. Saladin
Theses and Dissertations
This thesis studied the effect of microstructure on the fretting fatigue behavior of IN-100. First, fretting and plain fatigue S-N curves were determined over a large range of applied stress at an identical R-ratio and for fretting tests, done with a constant contact load. It was found that fretting fatigue reduces the cycles to failure compared to plain fatigue. The half contact width was found for the specimens, the crack initiation angle was found to be 40 deg and the crack initiation location was at the trailing edge of contact for the fretting specimens. Computational work included finding the stress …
Characterization Of Chlorinated Ethene Degradation In A Vertical Flow Constructed Wetland, James M. Waldron
Characterization Of Chlorinated Ethene Degradation In A Vertical Flow Constructed Wetland, James M. Waldron
Theses and Dissertations
Chlorinated solvents, including perchloroethene (PCE) and trichlorethene (TCE), are among the most common groundwater contaminants found in the United States. Once released into the environment, chlorinated solvents are extremely persistent and often require costly and lengthy remedial actions. The use of constructed wetlands has shown promise as an effective and less costly alternative for the treatment of chlorinated solvent contaminated groundwater. This study characterized and evaluated the concentration of chlorinated ethenes within a vertical flow constructed wetland, fed with PCE contaminated groundwater, at Wright-Patterson Air Force Base (WPAFB), Ohio. Chlorinated ethene concentrations were characterized within three distinct layers of the …
Using Value-Focused Thinking To Evaluate The Use Of Innovative Stormwater Management Technologies On Air Force Installations, Jeffrey T. Falcone
Using Value-Focused Thinking To Evaluate The Use Of Innovative Stormwater Management Technologies On Air Force Installations, Jeffrey T. Falcone
Theses and Dissertations
Stormwater runoff occurs naturally after every storm event; however, traditional development practices have created many impervious surfaces, such as buildings, parking lots, and streets that increase runoff volume and flow rate. Conventional stormwater management practices focus on collecting runoff into centralized channels and conveying it as quickly as possible to local bodies of water. This type of conveyance system decreases the opportunity for stormwater to naturally infiltrate back into the ground. It also prevents contaminants from being naturally filtered out of stormwater flows. As a result, centralized conveyance systems can cause flooding, erosion, and terrestrial and aquatic habitat degradation. Innovative …
Microbial Degradation Of Fuel Oxygenates Under Aerobic Conditions, John M. Dietz
Microbial Degradation Of Fuel Oxygenates Under Aerobic Conditions, John M. Dietz
Theses and Dissertations
This research determined the rate and extent of aerobic biodegradation of fuel oxygenates ethyl tert butyl ether (ETBE), tert amyl methyl ether (TAME), and ethyl alcohol (ethanol). Biodegradation was measured using gas chromatography (GC), respirometry, and biochemical oxygen demand (BOD) tests. Additionally, the research determined the effects of toluene on degradation rates. This microcosm study used a microbial consortium obtained from a petroleum refinery wastewater treatment facility. Respirometry data were collected from chambers containing pure oxygenates, or oxygenate/toluene mixtures. Samples were withdrawn periodically for GC analysis. Aerobic conditions were maintained in the chambers at all times. The five-day BOD test …
Recommendations For A Standardized Program Management Office (Pmo) Time Compliance Network Order (Tcno) Patching Process, Michael Czumak Iii
Recommendations For A Standardized Program Management Office (Pmo) Time Compliance Network Order (Tcno) Patching Process, Michael Czumak Iii
Theses and Dissertations
Network security is a paramount concern for organizations utilizing computer technology, and the Air Force is no exception. Network software vulnerability patching is a critical determinant of network security. The Air Force deploys these patches as Time Compliance Network Orders (TCNOs), which together with associated processes and enforced timelines ensure network compliance. While the majority of the network assets affected by this process are Air Force owned and operated, a large number are maintained by external entities known as Program Management Offices (PMOs). Although these externally controlled systems provide a service to the Air Force and reside on its network, …
Towards The Development Of A Defensive Cyber Damage And Mission Impact Methodology, Larry W. Fortson Jr.
Towards The Development Of A Defensive Cyber Damage And Mission Impact Methodology, Larry W. Fortson Jr.
Theses and Dissertations
The purpose of this research is to establish a conceptual methodological framework that will facilitate effective cyber damage and mission impact assessment and reporting following a cyber-based information incidents. Joint and service guidance requires mission impact reporting, but current efforts to implement such reporting have proven ineffective. This research seeks to understand the impediments existing in the current implementation and to propose an improved methodology. The research employed a hybrid historical analysis and case study methodology for data collection through extensive literature review, examination of existing case study research and interviews with Air Force members and civilian personnel employed as …
An Evaluation Of Organizational And Experience Factors Affecting The Perceived Transfer Of U.S. Air Force Basic Combat Skills Training, Shirley D. Crow
An Evaluation Of Organizational And Experience Factors Affecting The Perceived Transfer Of U.S. Air Force Basic Combat Skills Training, Shirley D. Crow
Theses and Dissertations
The United States Air Force is in a state of transformation. Due to ongoing operations in Iraq and Afghanistan, the focus of Basic Military Training is shifting to basic combat skills, or the skills needed to survive and operate in a hostile environment. In this study, basic combat skills training was evaluated using a number of training factors that potentially affect trainees’ perception of training transfer, or their ability to apply the skills they learned in training on the job or in a hostile environment. The analysis used structural equation modeling to evaluate the paths between each of the factors …
Real Options As A Stragetic Management Framework: A Case Study Of The Operationally Responsive Space Initiative, Robert H. Mitchell Jr.
Real Options As A Stragetic Management Framework: A Case Study Of The Operationally Responsive Space Initiative, Robert H. Mitchell Jr.
Theses and Dissertations
The purpose of this research was to examine the potential for applying the concept of real options to the DoD acquisition system. The key premise of real options is the application of strategic decision making and flexibility in the face of future uncertainties. This thesis sought to answer three research questions, how could real options be applied to the acquisition system, how could the acquisition system benefit, and what are the potential challenges to implementation within the acquisition system. These research questions were addressed through a comprehensive literature and a case study of the Operationally Responsive Space (ORS) initiative. The …
A Meta-Analysis Of Questionaire Response Rates In Military Samples, Michael R. Parrish
A Meta-Analysis Of Questionaire Response Rates In Military Samples, Michael R. Parrish
Theses and Dissertations
The purpose of this research was to examine if factors related to questionnaire response rate in the general public also affect response rate in military-only samples. Very little research pertaining to this specific group was located during the literature review. Four response rate factors taken from studies conducted in the general public were selected for this research topic: questionnaire length, questionnaire delivery mode (postal, e-mail, web-based, direct administration, and mixed mode), use of advance notices, and use of follow-up reminders. Data were gathered for a meta-analysis of 73 previously published studies which utilized a survey or questionnaire to collect data …
Optimizing The Prioritization Of Natural Disaster Recovery Projects, Jason M. Aftanas
Optimizing The Prioritization Of Natural Disaster Recovery Projects, Jason M. Aftanas
Theses and Dissertations
Prioritizing reconstruction projects to recover a base from a natural disaster is a complicated and arduous process that involves all levels of leadership. The project prioritization phase of base recovery has a direct affect on the allocation of funding, the utilization of human resources, the obligation of projects, and the overall speed and efficiency of the recovery process. The focus of this research is the development of an objective and repeatable process for optimizing the project prioritization phase of the recovery effort. This work will focus on promoting objectivity in the project prioritizing process, improving the communication of the overall …
Quantification Of Risk For Usaf Fire And Emergency Services Flights As A Result Of Shortage In Manpower, Timothy D. Dalby
Quantification Of Risk For Usaf Fire And Emergency Services Flights As A Result Of Shortage In Manpower, Timothy D. Dalby
Theses and Dissertations
The United States Air Force (USAF) is currently experiencing a period of high operations tempo and overseas deployments have become frequent. These deployments will leave home installations short manned. Some amount of risk is incurred by the home installation as a result of the short manning. For an organization, such as an USAF Fire and Emergency Services (FES) flight, whose primary responsibility is the protection of life and property, the incurred risk could be catastrophic. Still no attempt has been made to quantify risk in terms of manpower for the USAF FES flights. The primary purpose of this research was …
The Chaos Of Katrina: A Nonlinear Analysis Of Federal Logistics Support During Hurricane Katrina Relief Operations, Gerald W. Morris Jr.
The Chaos Of Katrina: A Nonlinear Analysis Of Federal Logistics Support During Hurricane Katrina Relief Operations, Gerald W. Morris Jr.
Theses and Dissertations
This thesis presents a case study of federal logistics support during Hurricane Katrina disaster relief operations. Data from federal contracts covering the first 10 weeks of Katrina are used to measure federal logistics activity. The study investigates whether chaos theory, part of complexity science, can extract information from Katrina contracting data to help managers make better logistics decisions during disaster relief operations. The study uses three analytical techniques: embedding, fitting the data to a logistic equation, and plotting the limit-cycle. Embedding and fitting a logistic equation to the data were used to test for deterministic chaos. The logistic equation and …
An Analysis Of Robust Workforce Scheduling Models For A Nurse Rostering Problem, Paul K. Tower
An Analysis Of Robust Workforce Scheduling Models For A Nurse Rostering Problem, Paul K. Tower
Theses and Dissertations
Disruptions impacting workforce schedules can be costly. A 1999 study of the United Kingdom's National Health Service estimated that as much as 4% of the total resources spent on staffing were lost to schedule disruptions like absenteeism. Although disruptions can not be eliminated, workforce schedules can be improved to be more responsive to disruptions. One key area of study that has expanded over the past few years is the application of traditional scheduling techniques to re-rostering problems. These efforts have provided methods for responding to schedule disruptions, but typically require deviations to the disrupted schedule. This thesis examines five workforce …
Improved Hyperspectral Image Testing Using Synthetic Imagery And Factorial Designed Experiments, Joseph P. Bellucci
Improved Hyperspectral Image Testing Using Synthetic Imagery And Factorial Designed Experiments, Joseph P. Bellucci
Theses and Dissertations
The goal of any remote sensing system is to gather data about the geography it is imaging. In order to gain knowledge of the earth's landscape, post-processing algorithms are developed to extract information from the collected data. The algorithms can be intended to classify the various ground covers in a scene, identify specific targets of interest, or detect anomalies in an image. After the design of an algorithm comes the difficult task of testing and evaluating its performance. Traditionally, algorithms are tested using sets of extensively ground truthed test images. However, the lack of well characterized test data sets and …
Critical Infrastructure Rebuild Prioritization Using Simulation Optimization, Namsuk Cho
Critical Infrastructure Rebuild Prioritization Using Simulation Optimization, Namsuk Cho
Theses and Dissertations
This thesis examines the importance of a critical infrastructure rebuild strategy following a terrorist attack or natural disaster such as Hurricane Katrina. Critical infrastructures are very complex and dependent systems in which their re-establishment is an essential part of the rebuilding process. A rebuild simulation model consisting of three layers (physical, information, and spatial) captures the dependency between the six critical infrastructures modeled. We employ a simulation optimization approach to evaluate rebuild prioritization combinations with a goal of minimizing the time needed to achieve an acceptable rebuild level. We use a simulated annealing heuristic as an optimization technique that works …
Approximate Analysis Of An Unreliable M/M/2 Retrial Queue, Brian P. Crawford
Approximate Analysis Of An Unreliable M/M/2 Retrial Queue, Brian P. Crawford
Theses and Dissertations
This thesis considers the performance evaluation of an M/M/2 retrial queue for which both servers are subject to active and idle breakdowns. Customers may abandon service requests if they are blocked from service upon arrival, or if their service is interrupted by a server failure. Customers choosing to remain in the system enter a retrial orbit for a random amount of time before attempting to re-access an available server. We assume that each server has its own dedicated repair person, and repairs begin immediately following a failure. Interfailure times, repair times and times between retrials are exponentially distributed, and all …
Analyzing The Interdiction Of Sea-Borne Threats Using Simulation Optimization, Kristen L. Cavallaro
Analyzing The Interdiction Of Sea-Borne Threats Using Simulation Optimization, Kristen L. Cavallaro
Theses and Dissertations
Worldwide, maritime trade accounts for approximately 80% of all trade by volume and is expected to double in the next twenty years. Prior to September 11, 2001, Ports, Waterways and Coastal Security (PWCS) was afforded only 1 percent of United States Coast Guard (USCG) resources. Today, it accounts for nearly 22 percent of dedicated USCG resources. Tactical assessment of resource requirements and operational limitations on the PWCS mission is necessary for more effective management of USCG assets to meet the broader range of competing missions. This research effort involves the development and validation of a discrete-event simulation model of the …