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Influence Of Ph On The Transport Of Silver Nanoparticles In Saturated Porous Media: Laboratory Experiments And Modeling, Jason R. Flory Mar 2012

Influence Of Ph On The Transport Of Silver Nanoparticles In Saturated Porous Media: Laboratory Experiments And Modeling, Jason R. Flory

Theses and Dissertations

Given the ubiquity of silver nanoparticles (AgNPs), the largest and fastest growing category of nanomaterials, and their potential for toxic effects to both humans and the environment, it is important to understand their environmental fate and transport. The purpose of this study is to gain information on the transport properties of unmodified AgNP suspensions in a glass bead-packed column under saturated flow conditions at different solution pH levels. Commercial AgNPs were characterized using high resolution transmission spectroscopy (HRTEM), dynamic light scattering (DLS) and ultraviolet (UV) visible spectroscopy. Transport data were collected at different pH levels (4, 6.5 and 9) at …


Modeling, Simulation, And Flight Test For Automatic Flight Control Of The Condor Hybrid-Electric Remote Piloted Aircraft, Christopher Giacomo Mar 2012

Modeling, Simulation, And Flight Test For Automatic Flight Control Of The Condor Hybrid-Electric Remote Piloted Aircraft, Christopher Giacomo

Theses and Dissertations

This thesis describes the modeling and verification process for the stability and control analysis of the Condor hybrid-electric Remote-Piloted Aircraft (HE-RPA). Due to the high-aspect ratio, sailplane-like geometry of the aircraft, both longitudinal and lateral/directional aerodynamic moments and effects are investigated. The aircraft is modeled using both digital DATCOM as well as the JET5 Excel-based design tool. Static model data is used to create a detailed assessment of predictive flight characteristics and PID autopilot gains that are verified with autonomous flight test. PID gain values were determined using a six degree of freedom linear simulation with the Matlab/SIMULINK software. Flight …


Security Standards And Best Practice Considerations For Quantum Key Distribution (Qkd), Carole A. Harper Mar 2012

Security Standards And Best Practice Considerations For Quantum Key Distribution (Qkd), Carole A. Harper

Theses and Dissertations

Quantum Key Distribution (QKD) systems combine cryptographic primitives with quantum information theory to produce a theoretic unconditionally secure cryptographic key. However, real-world implementations of QKD systems are far from ideal and differ significantly from the theoretic model. Because of this, real-world QKD systems require additional practical considerations when implemented to achieve secure operations. In this thesis, a content analysis of the published literature is conducted to determine if established security and cryptographic standards and best practices are addressed in real world, practical QKD implementations. The research reveals that most published, real world QKD implementations do not take advantage of established …


Improving Effectiveness Of Monetary Weapon Systems In Afghanistan, Seth M. Lorimer Mar 2012

Improving Effectiveness Of Monetary Weapon Systems In Afghanistan, Seth M. Lorimer

Theses and Dissertations

Tenuous political and economic times call for increased oversight and improved results from military counterinsurgency programs in Afghanistan, programs that provide agile non-kinetic weapons, critical for commanders fighting in today's asymmetric battle space. This paper proposes a decision tool for construction projects executed under the Commanders Emergency Response Program, designed to meet the changing demands of fighting an amorphous insurgency among dynamic systems of stakeholders. The research first conducted a system analysis of the CERP project execution process identifying key findings addressing value adding inputs. The research then applies a Causal Chain, borrowed from the Emergency Management field to identify …


Analysis Of The Impact Of Data Normalization On Cyber Event Correlation Query Performance, Smile T. Ludovice Mar 2012

Analysis Of The Impact Of Data Normalization On Cyber Event Correlation Query Performance, Smile T. Ludovice

Theses and Dissertations

A critical capability required in the operation of cyberspace is the ability to maintain situational awareness of the status of the infrastructure elements that constitute cyberspace. Event logs from cyber devices can yield significant information, and when properly utilized they can provide timely situational awareness about the state of the cyber infrastructure. In addition, proper Information Assurance requires the validation and verification of the integrity of results generated by a commercial log analysis tool. Event log analysis can be performed using relational databases. To enhance database query performance, previous literatures affirm denormalization of databases. Yet database normalization can also increase …


Optimization Of Nanoscale Zero-Valent Iron For The Remediation Of Groundwater Contaminants, Andrew W. E. Mcpherson Mar 2012

Optimization Of Nanoscale Zero-Valent Iron For The Remediation Of Groundwater Contaminants, Andrew W. E. Mcpherson

Theses and Dissertations

Nanoscale zero-valent iron (nZVI) is an emerging tool for the remediation of groundwater contaminants. The nanoparticles are capable of reductively destroying or immobilizing a wide range of contaminants. Their small size results in a high surface area to mass ratio, making them much more reactive compared to their more-coarse predecessors. Small particle size also allows nZVI particles to be injected directly into contaminated areas via a well, limiting the above-ground footprint and allowing access to contaminated areas that are beyond the reach of some conventional methods. nZVI technology has the potential to facilitate remediation in difficult situations, improve remediation outcomes, …


Prototyping The Use Of Dispersion Models To Predict Ground Concentrations During Burning Of Deployed Military Waste, Val Oppenheimer Mar 2012

Prototyping The Use Of Dispersion Models To Predict Ground Concentrations During Burning Of Deployed Military Waste, Val Oppenheimer

Theses and Dissertations

United States military forces in Iraq and Afghanistan have often used open burning of solid waste as a means to achieve volume reduction and to minimize vector borne illnesses. Assessing exposures to burn pit emissions has proven challenging, requiring significant numbers of personnel and sampling equipment. This study examined the use of three common dispersion models to determine the feasibility of using software modeling to predict short-range exposures to burn pit emissions, in lieu of sole reliance on ground sampling. Four open burn tests of municipal solid waste were conducted at Tooele Army Depot, Utah. Aerial samples were collected above …


An Enhanced Fuselage Ultrasound Inspection Approach For Ishm Purposes, Francisco Ospina Mar 2012

An Enhanced Fuselage Ultrasound Inspection Approach For Ishm Purposes, Francisco Ospina

Theses and Dissertations

This effort constitutes a systems engineering approach in which the materials science, ultrasound structural health monitoring, flight and maintenance operations, and relevant aeronautical policies and programs are involved to explore the evolution and characterization of structural cracks in aircraft fuselage structures in which the loads are varying. During flight, an aircraft fuselage skin and structure are subjected to varied cyclic loads, which can cause embedded cracks and other damage features to change their characteristics due to loading effects. The current research is based in the application of finite element modeling techniques using COMSOL and PZFLEX software to characterize the behavior …


Analysis Of Leadership In Energy And Environmental Design® Construction In The Air Force, James M. Rozzoni Mar 2012

Analysis Of Leadership In Energy And Environmental Design® Construction In The Air Force, James M. Rozzoni

Theses and Dissertations

The Air Force uses the Leadership in Energy and Environmental Design (LEED) rating system as a third party verification system to ensure sustainable and resource-conscious facilities. The Federal Government has implemented several mandates in recent years that require certain milestones be met for energy reduction, water conservation, renewable energy use, and so forth. This research aims to determine how the Air Force has implemented LEED through credit analysis, and to better understand why LEED is being used in this way. Using a database of 172 military construction projects, the research evaluates the frequency of credit usage individually and by category. …


A Spatial Risk Analysis Of Oil Refineries Within The United States, Zachary L. Schiff Mar 2012

A Spatial Risk Analysis Of Oil Refineries Within The United States, Zachary L. Schiff

Theses and Dissertations

A risk analysis methodology is necessary to manage the potential effects of oil refinery outages to the increasingly connected, interdependent critical infrastructure of the United States. Following the terrorist attacks of 9/11, the lack of a critical infrastructure risk mitigation strategy was identified as an area for improvement. In both the 9/11 attacks and Hurricane Katrina, cascading failures occurred due to the interdependencies among infrastructures and their spatial relationships. Furthermore, the U.S. military is dependent on oil refining capability and a major shortage could potentially have devastating effects on mission accomplishment. As a result, a need has emerged to better …


Modeling The Impact Of Cracking In Low Permeability Layers In A Groundwater Contamination Source Zone On Dissolved Contamination Source Zone On Dissolved Contaminant Fate And Transport, Katherine W. Sievers Mar 2012

Modeling The Impact Of Cracking In Low Permeability Layers In A Groundwater Contamination Source Zone On Dissolved Contamination Source Zone On Dissolved Contaminant Fate And Transport, Katherine W. Sievers

Theses and Dissertations

The storage and transport of a dense non-aqueous phase liquid (DNAPL) was evaluated using a numerical model. Many DNAPLs are used as solvents by the DoD and industry. The improper disposal and handling of these chemicals has led to long term contamination of groundwater. When spilled, a DNAPL will pool atop low permeability layers and slowly dissolve creating a contaminant plume. The dissolved contaminant within a low permeability layer serves as long-term sources of contamination once the source is removed. In this study, cracks are hypothesized to exist in the low permeability layers, allowing for enhanced transport. A numerical model …


Implementing A Quantitative Analysis Design Tool For Future Generation Interfaces, Brandon M. Webster Mar 2012

Implementing A Quantitative Analysis Design Tool For Future Generation Interfaces, Brandon M. Webster

Theses and Dissertations

The implementation of Multi-Aircraft Control (MAC) for use with Remotely Piloted Aircraft (RPA) has resulted in the need of a platform to evaluate interface design. The Vigilant Spirit Control Station (VSCS), developed by the Air Force Research Laboratory, addresses this need by permitting the rapid prototyping of different interface concepts for future MAC-enabled systems. A human-computer interaction (HCI) Index, originally applied to multi-function displays was applied to the prototype Vigilant Spirit interface. A modified version of the HCI Index was successfully applied to perform a quantitative analysis of the baseline VSCS interface and two modified interface designs. The modified HCI …


Emissions From Simulated Open Burning Of Deployed Us Military Waste, Brian D. Woodall Mar 2012

Emissions From Simulated Open Burning Of Deployed Us Military Waste, Brian D. Woodall

Theses and Dissertations

U.S. military forces have relied primarily on open burning as an expedient method of volume reduction and treatment of solid waste during the conflicts in Afghanistan and Iraq. This study is the first effort to characterize a broad range of pollutants and their emission factors during the burning of military waste and the effects that recycling efforts, namely removing plastics, might have on emissions. Piles of simulated military waste were constructed, burned, and emissions sampled at the U.S. Environmental Protection Agency (EPA) Open Burn Testing Facility (OBTF), Research Triangle Park, NC. Three tests contained polyethylene terephthalate (PET #1 or PET) …


A Dempster-Shafer Method For Multi-Sensor Fusion, Bethany G. Foley Mar 2012

A Dempster-Shafer Method For Multi-Sensor Fusion, Bethany G. Foley

Theses and Dissertations

The Dempster-Shafer Theory, a generalization of the Bayesian theory, is based on the idea of belief and as such can handle ignorance. When all of the required information is available, many data fusion methods provide a solid approach. Yet, most do not have a good way of dealing with ignorance. In the absence of information, these methods must then make assumptions about the sensor data. However, the real data may not fit well within the assumed model. Consequently, the results are often unsatisfactory and inconsistent. The Dempster-Shafer Theory is not hindered by incomplete models or by the lack of prior …


Decision Analysis Using Value-Focused Thinking For Retention Of Long-Term Officers In The Korean Army, Jaebum Kim Mar 2012

Decision Analysis Using Value-Focused Thinking For Retention Of Long-Term Officers In The Korean Army, Jaebum Kim

Theses and Dissertations

The North Korean attacks on the South Korean naval vessel, the Cheonan, and on the South Korean island of Yeonpyeong in 2010 have resulted in the deterioration of the relationship between North and South Korea. The death of Kim Jong Il in December 2011 has raised serious concerns over the future of North Korea and political stability on the Korean Peninsula. Against this background, South Korea has continued its agenda of military reform to improve the retention and management of its military personnel. However, South Korea needs better methods and measures for evaluating its personnel to distinguish highly qualified officers …


Aircraft Course Optimization Tool Using Gpops Matlab Code, Ryan D. Gauntt Mar 2012

Aircraft Course Optimization Tool Using Gpops Matlab Code, Ryan D. Gauntt

Theses and Dissertations

Aircraft course planning between two points in a clear, no threat environment is easy and straightforward. However, the addition of various threats can greatly increase the difficulty and complexity of course planning. Placing new waypoints along the edge of each threat, mostly skirting the dangerous environment, may not prove too difficult, but such courses are far from optimal. Given aircraft, environment, and time constraints it is likely a much more optimal path exists between any given start and end points. This research focuses on determining the feasibility of using the General Pseudospectral Optimization Software program files written for the MATLAB …


2011 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 Mar 2012

2011 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.


A Programmable Liquid Collimator For Both Coded Aperture Adaptive Imaging And Multiplexed Compton Scatter Tomography, Jack G. M. Fitzgerald Mar 2012

A Programmable Liquid Collimator For Both Coded Aperture Adaptive Imaging And Multiplexed Compton Scatter Tomography, Jack G. M. Fitzgerald

Theses and Dissertations

A novel, fully reconfigurable collimator device for gamma-ray and X-ray imaging was built and tested as a coded aperture. The device consisted of 10x10, 5x5x5 mm3 chambers. Each chamber either was filled with an attenuating liquid, stopping photons, or evacuated of the attenuating liquid, allowing the photons to pass through. As the pattern of on and off chambers was manipulated, different, semi-independent views of the gamma-ray source were found. Noise in reconstructed images decreased in all tests. Image reconstruction was performed with correlation methods and Maximum Likelihood Expectation Maximization (ML-EM). Using 10 mask patterns, the signal-to-noise ratio (SNR) in …


3-D Scene Reconstruction From Aerial Imagery, Jared M. Ekholm Mar 2012

3-D Scene Reconstruction From Aerial Imagery, Jared M. Ekholm

Theses and Dissertations

3-D scene reconstructions derived from Structure from Motion (SfM) and Multi-View Stereo (MVS) techniques were analyzed to determine the optimal reconnaissance flight characteristics suitable for target reconstruction. In support of this goal, a preliminary study of a simple 3-D geometric object facilitated the analysis of convergence angles and number of camera frames within a controlled environment. Reconstruction accuracy measurements revealed at least 3 camera frames and a 6 convergence angle were required to achieve results reminiscent of the original structure. The central investigative effort sought the applicability of certain airborne reconnaissance flight profiles to reconstructing ground targets. The data sets …


Sparsening Filter Design For Iterative Soft-Input Soft-Output Detectors, Raquel G. Machado, Andrew G. Klein, Richard K. Martin Feb 2012

Sparsening Filter Design For Iterative Soft-Input Soft-Output Detectors, Raquel G. Machado, Andrew G. Klein, Richard K. Martin

Faculty Publications

A large body of research exists around the idea of channel shortening, where a prefilter is designed to reduce the effective channel impulse response to some smaller number of contiguous taps. This idea was originally conceived to reduce the complexity of Viterbi-based maximum-likelihood equalizers. Here, we consider a generalization of channel shortening which we term "channel sparsening". In this case, a prefilter is designed to reduce the effective channel to a small number of nonzero taps which do not need to be contiguous. When used in combination with belief-propagation-based maximum a posteriori (MAP) detectors, an analogous complexity reduction can be …


Agent Based Modeling And Simulation Framework For Supply Chain Risk Management, Tiffany J. Harper Feb 2012

Agent Based Modeling And Simulation Framework For Supply Chain Risk Management, Tiffany J. Harper

Theses and Dissertations

This research develops a flexible agent-based modeling and simulation (ABMS) framework for supply chain risk management with significant enhancements to standard ABMS methods and supply chain risk modeling. Our framework starts with the use of software agents to gather and process input data for use in our simulation model. For our simulation model, we extend an existing mathematical framework for discrete event simulation (DES) to ABMS and then implement the concepts of variable resolution modeling from the DES domain to ABMS and provide further guidelines for aggregation and disaggregation of supply chain models. Existing supply chain risk management research focuses …


Modeling Small Unmanned Aerial System Mishaps Using Logistics Regression And Artificial Neural Networks, Sean E. Wolf Feb 2012

Modeling Small Unmanned Aerial System Mishaps Using Logistics Regression And Artificial Neural Networks, Sean E. Wolf

Theses and Dissertations

A dataset of 854 small unmanned aerial system (SUAS) flight experiments from 2005-2009 is analyzed to determine significant factors that contribute to mishaps. The data from 29 airframes of different designs and technology readiness levels were aggregated. 20 measured parameters from each flight experiment are investigated, including wind speed, pilot experience, number of prior flights, pilot currency, etc. Outcomes of failures (loss of flight data) and damage (injury to airframe) are classified by logistic regression modeling and artificial neural network analysis. From the analysis, it can be concluded that SUAS damage is a random event that cannot be predicted with …


Malware Target Recognition Via Static Heuristics, Thomas E. Dube, Richard A. Raines, Gilbert L. Peterson, Kenneth W. Bauer, Michael R. Grimaila, Steven K. Rogers Feb 2012

Malware Target Recognition Via Static Heuristics, Thomas E. Dube, Richard A. Raines, Gilbert L. Peterson, Kenneth W. Bauer, Michael R. Grimaila, Steven K. Rogers

Faculty Publications

Organizations increasingly rely on the confidentiality, integrity and availability of their information and communications technologies to conduct effective business operations while maintaining their competitive edge. Exploitation of these networks via the introduction of undetected malware ultimately degrades their competitive edge, while taking advantage of limited network visibility and the high cost of analyzing massive numbers of programs. This article introduces the novel Malware Target Recognition (MaTR) system which combines the decision tree machine learning algorithm with static heuristic features for malware detection. By focusing on contextually important static heuristic features, this research demonstrates superior detection results. Experimental results on large …


Air Force Institute Of Technology Research Report 2011, Office Of Research And Sponsored Programs, Graduate School Of Engineering And Management, Afit Jan 2012

Air Force Institute Of Technology Research Report 2011, 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.


Stereoscopic Display System With Flexible Rendering Of Disparity Map According To The Stereoscopic Fusing Capability Of The Observer, Elaine W. Jin, Michael E. Miller, Serguei Endrikhovski, Cathleen D. Cerosaletti Jan 2012

Stereoscopic Display System With Flexible Rendering Of Disparity Map According To The Stereoscopic Fusing Capability Of The Observer, Elaine W. Jin, Michael E. Miller, Serguei Endrikhovski, Cathleen D. Cerosaletti

AFIT Patents

A method is provided for customizing scene content, according to a user or a cluster of users, for a given stereoscopic display, including obtaining customization information about the user; obtaining a scene disparity map for a pair of given stereo images and/or a three-dimensional (3D) computer graphic model; and determining an aim disparity range for the user. The method of the present invention also generates a customized disparity map and/or rendering conditions for a three-dimensional (3D) computer graphic model correlating with the user's fusing capability of the given stereoscopic display; and renders or re-renders the stereo images for subsequent display.


Afit Graduate School Of Engineering And Management Catalog 2012-2013, Graduate School Of Engineering And Management, Air Force Institute Of Technology Jan 2012

Afit Graduate School Of Engineering And Management Catalog 2012-2013, 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.


Can You Hear Me Now? Assessing Students' Classroom Communication Preferences Via A Telephone Conference Activity, Sharon G. Heilmann Jan 2012

Can You Hear Me Now? Assessing Students' Classroom Communication Preferences Via A Telephone Conference Activity, Sharon G. Heilmann

Faculty Publications

Telephone conference presentation delivery was compared to face-to-face classroom delivery in an undergraduate business course setting to assess whether concern over presenting in front of the class and/or gender impacted presentation mode preference. After completing a classroom exercise, students (n=102) were surveyed and asked to compare delivery methods from two courses, one requiring a telephone conference and the other requiring a face-to-face classroom presentation, in terms of perceived effectiveness, feedback, teamwork, instructor cues, preparation time, and overall comfort. Independent sample t-test results indicated respondents who worried about presenting in front of the class believed the telephone conference format required more …


Acquiring Os X File Handles Through Forensic Memory Analysis, Andrew F. Hay, Gilbert L. Peterson Jan 2012

Acquiring Os X File Handles Through Forensic Memory Analysis, Andrew F. Hay, Gilbert L. Peterson

Faculty Publications

Memory analysis has become a critical capability in digital forensics because it provides insight into system state that cannot be fully represented through traditional media analysis. The volafox open source project has begun the work of structured memory analysis for OS X with support for a limited set of kernel structures. This paper addresses one memory analysis deficiency on OS X with the introduction of a new volafox module for parsing file handles associated with running processes. The developed module outputs information comparable to the UNIX lsof (list open files) command, which is used to validate the results.


Magnetic And Electronic Properties Of Thin (Ga,Mn)N Films Due To An Embedded Mn-Delta-Doping Layer, H. C. Jeon, S. J. Lee, Tae Won Kang, K. J. Chang, Yung Kee Yeo, T. F. George Dec 2011

Magnetic And Electronic Properties Of Thin (Ga,Mn)N Films Due To An Embedded Mn-Delta-Doping Layer, H. C. Jeon, S. J. Lee, Tae Won Kang, K. J. Chang, Yung Kee Yeo, T. F. George

Faculty Publications

The magnetization curve as a function of the magnetic field at 5 K showed that the magnetization in the (Ga0.995Mn0.005)N thin film was significantly enhanced due to Mn delta-doping. The magnetization curve as a function of the temperature showed that the Curie temperature of the Mn delta-doped (Ga0.995Mn0.005)N thin film was estimated to be above room temperature. The theoretical results showed that Ga vacancies near the Mn delta-doping layer were likely to cause p-type conductance in the (Ga0.995Mn0.005)N thin film. Abstract © 2011 AIP


Internal Electric Fields Due To Piezoelectric And Spontaneous Polarizations In Cdzno/Mgzno Quantum Well, H. C. Jeon, S. J. Lee, Tae Won Kang, S. H. Park, Yung Kee Yeo, T. F. George Dec 2011

Internal Electric Fields Due To Piezoelectric And Spontaneous Polarizations In Cdzno/Mgzno Quantum Well, H. C. Jeon, S. J. Lee, Tae Won Kang, S. H. Park, Yung Kee Yeo, T. F. George

Faculty Publications

We have investigated optical properties as a function of internal and external fields in the quantum well (QW). Optical properties of CdZnO/MgZnO QW structures are investigated by using many‐body effects. The CdZnO/MgZnO QW structure with high Cd composition is found to have smaller optical gain because the strain‐induced piezoelectric polarization and the spontaneous polarization in the well increase with the inclusion of Cd. These results demonstrate that high performance laser diode operation can be realized in CdZnO/MgZnO QW structures by reducing those polarizations adopting dipole reverse method.