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Weighted Key Player Problem For Social Network Analysis, Ryan M. Mcguire Mar 2011

Weighted Key Player Problem For Social Network Analysis, Ryan M. Mcguire

Theses and Dissertations

Social network analysis is a tool set whose uses range from measuring the impact of marketing campaigns to disrupting clandestine terrorist organizations. Social network analysis tools are primarily focused on the structure of relationships between actors in the network. However, characteristics of the actors, such as importance or status, are generally the output of the social network analysis rather than an input. Characteristics of actors can come from a number of sources to include information gathering, subject matter experts or social network analysis. Further, the strength of relationships between actors in social networks are often assumed to be all equal. …


Decision Analysis And Validation Of Value Focused Thinking Decision Models Using Multivariate Analysis Techniques, James L. Pruitt Mar 2011

Decision Analysis And Validation Of Value Focused Thinking Decision Models Using Multivariate Analysis Techniques, James L. Pruitt

Theses and Dissertations

Decision Analysis (DA) is a useful tool to assist decision makers (DM) with difficult and complex decisions using mathematical models. Value Focused Thinking (VFT) models are a useful DA tool widely employed in the Air Force. However, VFT models are rarely validated. This research will attempt to validate any given VFT model and provide insight into the discriminating attributes of the alternative set. First, a two group discriminant analysis is applied the alternative set given the prior knowledge of the selected alternatives. Next, compromise programming is used attempt to minimize the distance between the posterior probability of an alternative being …


Application Of Post Modern Portfolio Theory To Mitigate Risk In International Shipping, Michael R. Quashne Mar 2011

Application Of Post Modern Portfolio Theory To Mitigate Risk In International Shipping, Michael R. Quashne

Theses and Dissertations

This research uses asset allocation concepts to determine the correct amount of cargo to send down the PAKGLOC and NDN to minimize the risk of loss or damage. Loss and Damage data is used from Transportation Discrepancy Reports and overall value is assumed to match the industry standard. Using assumed levels of pilferage along the NDN, a Monte Carlo simulation is run at each level of pilferage, and a Co-Lower Partial Moment model is solved. Analysis of the data shows a wide spread of possible optimal solutions at each level of pilferage. Due to the low levels of risk along …


Empirical Characterization Of Ballistic Impact Flash, Thomas P. Talafuse Mar 2011

Empirical Characterization Of Ballistic Impact Flash, Thomas P. Talafuse

Theses and Dissertations

Fires onboard aircraft are leading mechanisms for mishaps and losses during peacetime and combat operations. Typical ignition sources causing fires onboard aircraft include electrical sparks and hot surfaces. However, impact and penetration of common threats encountered during combat operations, such as armor piercing incendiary projectiles and missile fragments, generate short-lived, but thermally-intense clouds (flashes) capable of igniting fires. Fire simulations supporting system-level survivability analyses depend on accurate characterization of these flash clouds, however, such accurate representations are not currently available. This research presents the modeling approach developed to estimate the boundary model representations of impact flashes. The research presents generalized …


Life Cycle Assessment Of Leed Vs. Conventionally Built Residential Units, Woo-Suk Chun Mar 2011

Life Cycle Assessment Of Leed Vs. Conventionally Built Residential Units, Woo-Suk Chun

Theses and Dissertations

The United States Air Force constructed 1,028 energy efficient homes at Biloxi, MS. To analyze and compare these energy efficient homes to conventionally built homes, this study employed a hybrid LCA and energy simulation. These energy efficient homes have a 16% less environmental impact, consume 15% less energy, and save 2% in total life cycle cost while incurring a 1% cost increase in project construction compared to conventional homes. The simple payback period of the project to payback this initial 1% construction cost increase is 10 years. The most effective energy efficient measure implemented was increasing the air conditioning seasonal …


New Media Analysis: The Effects Of Peer Influence And Personality Characteristics Through The Stages Of Trial, Adoption, And Continued Use Of Video Sharing Websites, Joseph L. Hicks Mar 2011

New Media Analysis: The Effects Of Peer Influence And Personality Characteristics Through The Stages Of Trial, Adoption, And Continued Use Of Video Sharing Websites, Joseph L. Hicks

Theses and Dissertations

New Media technologies have evolved at a rapid pace and have changed the way people communicate in the digital world. These changes are apparent in practically every type of application, including business, leisure, and the way people socially interact. The primary goal of this research was to contribute to the current breadth of knowledge and understanding regarding how, why, and under what conditions people interact with New Media technologies. In order to achieve this objective, this research provides an understanding of how peer influence and individual personality characteristics interact across time through the stages of New Media trial, adoption, and …


Personality And Social Influence Characteristic Affects On Ease Of Use And Peer Influence Of New Media Users Over Time, David M. Ho Mar 2011

Personality And Social Influence Characteristic Affects On Ease Of Use And Peer Influence Of New Media Users Over Time, David M. Ho

Theses and Dissertations

New Media technologies such as social networking sites (SNSs) have taken the world by storm. Millions of people across the world are forming large social networks through these internet-based SNSs by sharing similar interests, friends, and personal information. New Media technologies now allow people to communicate messages to a greater audience through these networks not previously seen before in other technologies. This research seeks to understand these New Media users by examining the personality and social influence characteristics through the three phases of New Media acceptance: trial, adoption, and continual use. The study administered one-hour interviews to 64 university students …


Using Earned Value Data To Detect Potential Problems In Acquisition Contracts, C. Grant Keaton Mar 2011

Using Earned Value Data To Detect Potential Problems In Acquisition Contracts, C. Grant Keaton

Theses and Dissertations

Government contractors report earned value (EV) information to government agencies in monthly Contract Performance Reports (CPR). Though major differences may exist in the data between subsequent CPRs, we know of no government effort to detect these occurrences. The identification of major changes may locate and isolate problems and thus prevent million and billion dollar cost and schedule overruns. In this study, we develop an approach to identify changes in the Cost Performance Index (CPI) and the Schedule Performance Index (SPI) that may indicate problems with contract performance. We find the detection algorithm indentifies changes in the CPI and the SPI …


Composite Aircraft Life Cycle Cost Estimating Model, Daniel B. Lambert Mar 2011

Composite Aircraft Life Cycle Cost Estimating Model, Daniel B. Lambert

Theses and Dissertations

Composite materials are beginning to comprise a greater percentage of structural materials used throughout aircraft production. The increased usage of composites has led individuals within the Air Force community to revisit aircraft life cycle cost, LCC, models. A series of affordability initiatives has culminated in significant evidence over the last decade to better quantify the impact of primarily composite structures in aircraft. The Advanced Composite Cargo Aircraft, ACCA, a research effort sponsored by the Air Force Research Lab, attempted to determine the impact of part size and large scale composite components on LCC for cargo aircraft. This research evaluates the …


Modeling Enhanced Storage Of Groundwater Contaminants Due To The Presence Of Cracks In Low Permeability Zones Underlying Contaminant Source Areas, Jeremy M. Miniter Mar 2011

Modeling Enhanced Storage Of Groundwater Contaminants Due To The Presence Of Cracks In Low Permeability Zones Underlying Contaminant Source Areas, Jeremy M. Miniter

Theses and Dissertations

Throughout DoD, chlorinated aliphatic hydrocarbons (CAHs), a type of Dense Non-Aqueous Phase Liquid (DNAPL), have been frequently used. In the subsurface, spilled DNAPLs may pool atop low permeability clay layers. In this study a numerical model is constructed using the Groundwater Modeling System to assess how cracks in the clay, either pre-existing or the result of DNAPL-clay interactions, might impact a dissolved CAH plume generated by the DNAPL source. The conceptual model posits a DNAPL source in a high permeability sand aquifer sitting atop a low permeability clay layer. The model assumes dissolved CAH generated by the DNAPL is transported …


Degradation Modeling Of Polyurea Pavement Markings, Jonathan D. Needham Mar 2011

Degradation Modeling Of Polyurea Pavement Markings, Jonathan D. Needham

Theses and Dissertations

Polyurea is a long life pavement marking material used for assets requiring long periods of uninterrupted accessibility. Knowing the performance characteristics of such markings is critical to asset management planning focused on maximizing marking material life-cycles. This paper presents the performance characteristics of polyurea pavement markings in North Carolina using linear regression models. The models generated by this research provide pavement marking managers with tools to better allocate limited manpower and resources in order to optimize budgets while meeting newly proposed pavement marking retroreflectivity levels of service as proposed by the Federal Highway Administration. This research constructed performance models for …


Measuring The Utility Of A Cyber Incident Mission Impact Assessment (Cimia) Process For Mission Assurance, Christy L. Peterson Mar 2011

Measuring The Utility Of A Cyber Incident Mission Impact Assessment (Cimia) Process For Mission Assurance, Christy L. Peterson

Theses and Dissertations

Information is a critical asset on which virtually all modern organizations depend upon to meet their operational mission objectives. Military organizations, in particular, have embedded Information and Communications Technologies (ICT) into their core mission processes as a means to increase their operational efficiency, exploit automation, improve decision quality, and shorten the kill chain. However, the extreme dependence upon ICT results in an environment where a cyber incident can result in severe mission degradation, or possibly failure, with catastrophic consequences to life, limb, and property. These consequences can be minimized by maintaining real-time situational awareness of mission critical resources so appropriate …


Retrospective Geospatial Modeling Of Pm10 Exposures From Open Burning At Joint Base Balad, Iraq, John P. Rinker Mar 2011

Retrospective Geospatial Modeling Of Pm10 Exposures From Open Burning At Joint Base Balad, Iraq, John P. Rinker

Theses and Dissertations

Predicting, determining, and linking theater-related source-specific exposures to health effects has proven difficult. The purpose of this research is to delineate retrospective exposure zones using spatially interpolated particulate air sampling point data from Joint Base Balad, create burn pit exposure isopleths from dispersion model outputs, and merge into a combined exposure model in GIS. Interpolated monitoring results and dispersion modeled results were combined to compare modeled exposures across base. Burn pit contribution to total PM10 was also modeled. The combined dispersion and interpolation map showed elevated concentrations within a 1 kilometer buffer of the burn pit. Buildings within this area …


Modeling Vertical Flow Treatment Wetland Hydraulics To Optimize Treatment Efficiency, David T. Roen Ii Mar 2011

Modeling Vertical Flow Treatment Wetland Hydraulics To Optimize Treatment Efficiency, David T. Roen Ii

Theses and Dissertations

An upward Vertical Flow Treatment Wetland (uVFTW) at Wright Patterson AFB designed to bioremediate contaminated groundwater exhibits hydraulic short-circuiting. Prior studies estimated that groundwater flowed through less than 50% of the wetland’s volume, and that the mean residence time was significantly less than the nominal residence time, which was calculated assuming flow through the entire wetland volume. The objective of this research was to investigate how uVFTW hydraulics affects treatment efficiency, and to propose design strategies to maximize treatment efficiency. A groundwater flow and contaminant transport model of a uVFTW that couples hydraulics and degradation kinetics was built and applied …


Characterization Of Graphite Composite Material Particulates From Usaf Aircraft Maintenance Operations, Richard E. Yon Mar 2011

Characterization Of Graphite Composite Material Particulates From Usaf Aircraft Maintenance Operations, Richard E. Yon

Theses and Dissertations

Due to the benefits of their material properties, advanced composite materials (ACM) are increasingly being used as structural components on aircraft, especially within the United States Air Force. As a result, the potential exists for occupational exposures to structural maintenance employees while repairing and fabricating aircraft components. Two field studies were conducted for this thesis in order to characterize ACM aerosol size distribution, determine the feasibility of utilizing direct reading instruments (DRIs) in the field, and ensure workers are protected with adequate controls. In order to characterize exposure, traditional integrated air sampling and DRIs were positioned together near an ACM …


Improving The Efficiency Of Photon Collection By Compton Rescue, Alexander W. Stevenson Mar 2011

Improving The Efficiency Of Photon Collection By Compton Rescue, Alexander W. Stevenson

Theses and Dissertations

A method to improve the efficiency of photon collection in thin planar HPGe detectors was investigated. The method involved implementing a second HPGe detector to collect Compton scattered photons from the primary detector and incorporating coincident interactions in the two detectors that sum to the full energy event into the energy spectrum. This method is termed Compton rescue because the Compton scattered photons make a partial energy deposition in the primary detector and are added back to the spectrum after being detected by the second detector. This research has implications on improving the efficiency of positron annihilation spectroscopy (PAS) techniques …


Determining Solution Space Characteristics For Real-Time Strategy Games And Characterizing Winning Strategies, Gary B. Lamont, Kurt Weissgerber, Brett J. Borghetti, Gilbert L. Peterson Mar 2011

Determining Solution Space Characteristics For Real-Time Strategy Games And Characterizing Winning Strategies, Gary B. Lamont, Kurt Weissgerber, Brett J. Borghetti, Gilbert L. Peterson

Faculty Publications

The underlying goal of a competing agent in a discrete real-time strategy (RTS) game is to defeat an adversary. Strategic agents or participants must define an a priori plan to maneuver their resources in order to destroy the adversary and the adversary's resources as well as secure physical regions of the environment. This a priori plan can be generated by leveraging collected historical knowledge about the environment. This knowledge is then employed in the generation of a classification model for real-time decision-making in the RTS domain. The best way to generate a classification model for a complex problem domain depends …


Manufacturing And Evaluation Of A Biologically Inspired Engineered Mav Wing Compared To The Manduca Sexta Wing Under Simulated Flapping Conditions, Nathanial E. Deleon Mar 2011

Manufacturing And Evaluation Of A Biologically Inspired Engineered Mav Wing Compared To The Manduca Sexta Wing Under Simulated Flapping Conditions, Nathanial E. Deleon

Theses and Dissertations

In recent years, researchers have expressed a vested interest in the concepts surrounding flapping wing micro air vehicles (FWMAVs) that are capable of both range and complex maneuvering. Most research in this arena has found itself concentrated on topics such as flapping dynamics and the associated fluid-structure interactions inherent in the motion, however there still remains myriad questions concerning the structural qualities intrinsic to the wings themselves. Using nature as the template for design, FWMAV wings were constructed using carbon fiber and Kapton and tested under simplified flapping conditions by analyzing frozen' digital images of the deformed wing by methods …


Shock Wave Dynamics Of Novel Aluminized Detonations And Empirical Model For Temperature Evolution From Post-Detonation Combustion Fireballs, Joe Motos Gordon Mar 2011

Shock Wave Dynamics Of Novel Aluminized Detonations And Empirical Model For Temperature Evolution From Post-Detonation Combustion Fireballs, Joe Motos Gordon

Theses and Dissertations

This research characterizes the blast wave and temperature evolution of an explosion fireball in order to improve the classification of aluminized conventional munitions based on a single explosive type such as RDX. A drag model fit to data shows initial shock velocities of 1.6-2.8 km/s and maximum fireball radii ranging from 4.3-5.8 m with most of the radii reached by 50 ms upon detonation. The Sedov-Taylor point blast model is fitted to data where a constant release (s=1) of energy upon detonation suggests shock energies of 0.5-8.9 MJ with blast dimensionalities indicative of the spherical geometry (n3) observed in visible …


Remote Quantification Of Smokestack Total Effluent Mass Flow Rates Using Imaging Fourier-Transform Spectroscopy, Jacob L. Harley Mar 2011

Remote Quantification Of Smokestack Total Effluent Mass Flow Rates Using Imaging Fourier-Transform Spectroscopy, Jacob L. Harley

Theses and Dissertations

A Telops Hyper-Cam midwave infrared (1.5 − 5.5μm) imaging Fourier-transform spectrometer (IFTS) was used to estimate industrial smokestack total effluent mass flow rates by combining spectrally-determined species concentrations with flow rates estimated via analysis of sequential images in the raw interferogram cube. Strong emissions from H2O, CO2, CO, SO2, and NO were observed in the spectrum. A previously established plume radiative transfer model was used to estimate gas concentrations, and a simple temporal cross-correlation analysis of sequential imagery enabled an estimation of the flow velocity. Final effluent mass flow rates for CO2 and …


Understanding The Influence Of Turbulence In Imaging Fourier-Transform Spectrometry Of Smokestack Plumes, Jennifer L. Massman Mar 2011

Understanding The Influence Of Turbulence In Imaging Fourier-Transform Spectrometry Of Smokestack Plumes, Jennifer L. Massman

Theses and Dissertations

An imaging Fourier-transform spectrometer (IFTS) was used to collect infrared hyper-spectral imagery of smokestack plume of a coal-burning power facility to assess the influence of turbulence on spectral retrieval of temperature (T) and pollutant concentrations (Ci). Radiance fluctuations due to plume turbulence introduced scene change artifacts (SCA) in the spectra. Time-averaging the spectra minimizes SCA magnitudes, but accurate T and Ci retrieval would require a priori knowledge of the statistical distribution of temperature and other stochastic flow field parameters. A method of quantile sorting in interferogram space that would allow the retrieval of the temperature distribution is …


Passive Ranging Of Dynamic Rocket Plumes Using Infrared And Visible Oxygen Attenuation, Robert Anthony Vincent Mar 2011

Passive Ranging Of Dynamic Rocket Plumes Using Infrared And Visible Oxygen Attenuation, Robert Anthony Vincent

Theses and Dissertations

Atmospheric oxygen absorption bands in observed spectra of boost phase missiles can be used to accurately estimate range from sensor to target. This work compares two oxygen absorption bands in the near-infrared (NIR) and visible (Vis) spectrum, centered at 762nm and 690 nm, to passively determine range. Spectra were observed from static tests of both surface-to-air missile simulators at 405m range and a full-scale solid rocket motor at 900m range. The NIR O2 band provided range estimates accurate to within 3% for both tests, while the Vis O2 band had range errors of 77% and 15 %, respectively. …


Estimating Cargo Airdrop Collateral Damage Risk, Vincent R. Cammarano Mar 2011

Estimating Cargo Airdrop Collateral Damage Risk, Vincent R. Cammarano

Theses and Dissertations

The purpose of this research is to determine an appropriate method for estimating cargo airdrop collateral damage risk. Specifically, this thesis answers the question: How can mission planners accurately predict airdrop collateral damage risk? The question is answered through a literature review and a thorough examination of a data set of real world airdrop scoring data. The data were examined to determine critical factors that affect airdrop error risks as well as to determine the characteristics of airdrop error patterns. Through this research it was determined that bivariate normal distributions with parameters pairs determined by empirical data are appropriate for …


Air Force Institute Of Technology Research Report 2010, Office Of Research And Sponsored Programs, Graduate School Of Engineering And Management, Afit Feb 2011

Air Force Institute Of Technology Research Report 2010, Office Of Research And Sponsored Programs, Graduate School Of Engineering And Management, Afit

AFIT Documents

This report summarizes the research activities of the Air Force Institute of Technology’s Graduate School of Engineering and Management. It describes research interests and faculty expertise; lists student theses/dissertations; identifies research sponsors and contributions; and outlines the procedures for contacting the school. Included in the report are: faculty publications, conference presentations, consultations, and funded research projects. Research was conducted in the areas of Aeronautical and Astronautical Engineering, Electrical Engineering and Electro-Optics, Computer Engineering and Computer Science, Systems and Engineering Management, Operational Sciences, Mathematics, Statistics and Engineering Physics


Energy Scaling Of Nanosecond Gain-Switched Cr2+:Znse Lasers, Vladimir V. Fedorov, Igor S. Moskalev, M. S. Mirov, S. B. Mirov, Torrey J. Wagner, Matthew J. Bohn, Patrick A. Berry, K. L. Schepler Feb 2011

Energy Scaling Of Nanosecond Gain-Switched Cr2+:Znse Lasers, Vladimir V. Fedorov, Igor S. Moskalev, M. S. Mirov, S. B. Mirov, Torrey J. Wagner, Matthew J. Bohn, Patrick A. Berry, K. L. Schepler

Faculty Publications

In this paper, we report record nanosecond output energies of gain-switched CrZnSe lasers pumped by Q-switched CrTmHoYAG 100 ns at 2.096 microns and Raman shifted NdYAG lasers 7 ns at 1.906 microns. In these experiments we used Brewster cut CrZnSe gain elements with a chromium concentration of 8x1018cm-3. Under CrTmHoYAG pumping, the first CrZnSe laser demonstrated 3.1 mJ of output energy, 52 slope efficiency and 110 nm linewidth centered at a wavelength of 2.47 microns. Maximum output energy of the second CrZnSe laser reached 10.1 mJ under H2 Raman shifted NdYAG laser pumping. The slope …


Detecting Software Attacks By Monitoring Electric Power Consumption Patterns, Grant A. Jacoby, Nathaniel J. Davis Iv, Randolph C. Marchany Jan 2011

Detecting Software Attacks By Monitoring Electric Power Consumption Patterns, Grant A. Jacoby, Nathaniel J. Davis Iv, Randolph C. Marchany

AFIT Patents

Software attacks such as worms and viruses are detected in an electronic device by monitoring power consumption patterns. In a first embodiment, software attacks are detected by an increase in power consumption. The increased power consumption can be caused by increased network traffic, or by increased activity in the microprocessor. Monitoring power consumption is particularly effective for detecting DOS/flooding attacks when the electronic device is in an idle state. In a second embodiment, a power consumption signal is converted to the frequency domain (e.g., by fast Fourier transform). The highest amplitude frequencies are identified. Specific software attacks produce characteristic frequencies …


Afit Graduate School Of Engineering And Management Catalog 2011–2012, Graduate School Of Engineering And Management, Air Force Institute Of Technology Jan 2011

Afit Graduate School Of Engineering And Management Catalog 2011–2012, Graduate School Of Engineering And Management, Air Force Institute Of Technology

AFIT Documents

The Graduate Catalog represents the offerings, programs, and requirements in effect at the time of publication.


Kinetic Solution Of The Structure Of A Shock Wave In A Nonreactive Gas Mixture, Eswar Josyula, Prakash Vedula, William F. Bailey, Casmir J. Suchyta Iii Jan 2011

Kinetic Solution Of The Structure Of A Shock Wave In A Nonreactive Gas Mixture, Eswar Josyula, Prakash Vedula, William F. Bailey, Casmir J. Suchyta Iii

Faculty Publications

The multispecies Boltzmann equation is numerically integrated to characterize the internal structure of a Mach 3 shock wave in a hard sphere gas. The collision integral is evaluated by the conservative discrete ordinate method [F. G. Tcheremissine, Comput. Math. Math. Phys. 46, 315 (2006)]. There was excellent agreement of macroscopic variables [Kosuge et al., Eur. J. Mech. B/Fluids 20, 87 (2001)]. The effect of species concentration and mass ratio on the behavior of macroscopic variables and distribution functions in the structure of the shock wave is considered for both two- and three-species gas mixtures. In a binary mixture of gases …


Real-Time Behavior-Based Robot Control, Brian G. Woolley, Gilbert L. Peterson, Jared T. Kresge Jan 2011

Real-Time Behavior-Based Robot Control, Brian G. Woolley, Gilbert L. Peterson, Jared T. Kresge

Faculty Publications

Behavior-based systems form the basis of autonomous control for many robots, but there is a need to ensure these systems respond in a timely manner. Unexpected latency can adversely affect the quality of an autonomous system’s operations, which in turn can affect lives and property in the real-world. A robots ability to detect and handle external events is paramount to providing safe and dependable operation. This paper presents a concurrent version of a behavior-based system called the Real-Time Unified Behavior Framework, which establishes a responsive basis of behavior-based control that does not bind the system developer to any single behavior …


An Fpga-Based System For Tracking Digital Information Transmitted Via Peer-To-Peer Protocols, Karl R. Schrader, Barry E. Mullins, Gilbert L. Peterson, Robert F. Mills Dec 2010

An Fpga-Based System For Tracking Digital Information Transmitted Via Peer-To-Peer Protocols, Karl R. Schrader, Barry E. Mullins, Gilbert L. Peterson, Robert F. Mills

Faculty Publications

This paper presents a Field Programmable Gate Array (FPGA)-based tool designed to process file transfers using the BitTorrent Peer-to-Peer (P2P) protocol and VoIP phone calls made using the Session Initiation Protocol (SIP). The tool searches selected control messages in real time and compares the unique identifier of the shared file or phone number against a list of known contraband files or phone numbers. Results show the FPGA tool processes P2P packets of interest 92% faster than a software-only configuration and is 97.6% accurate at capturing and processing messages at a traffic load of 89.6 Mbps.