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A Nanoporous Silicon Nitride Membrane Using A Two-Step Lift-Off Pattern Transfer With Thermal Nanoimprint Lithography, Bhargav P. Nabar, Zeynep Çelik-Butler, Brian H. Dennis, Richard E. Billo Apr 2012

A Nanoporous Silicon Nitride Membrane Using A Two-Step Lift-Off Pattern Transfer With Thermal Nanoimprint Lithography, Bhargav P. Nabar, Zeynep Çelik-Butler, Brian H. Dennis, Richard E. Billo

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Nanoimprint lithography is emerging as a viable contender for fabrication of large-scale arrays of 5500 nm features. A fabrication process for the realization of thin nanoporous membranes using thermal nanoimprint lithography is presented. Suspended silicon nitride membranes were fabricated by low-pressure chemical vapor deposition (LPCVD) in conjunction with a potassium hydroxide-based bulk micromachining process. Nanoscale features were imprinted into a commercially available thermoplastic polymer resist using a prefabricated silicon mold. The pattern was reversed and transferred to a thin aluminum oxide layer by means of a novel two-stage lift-off technique. The patterned aluminum oxide was used as an etch mask …


A Discrete Event Simulation Of Network Centric Operations: Modeling Unbalanced Combat Configurations In Symmetric Engagements, Mahmoud Turki Khasawneh Apr 2012

A Discrete Event Simulation Of Network Centric Operations: Modeling Unbalanced Combat Configurations In Symmetric Engagements, Mahmoud Turki Khasawneh

Engineering Management & Systems Engineering Theses & Dissertations

Network Centric Operations (NCO) has been dubbed the most significant revolution in military affairs (RMA) in the past 200 years. The promise of NCO is based on the notion that information sharing and connectivity is fundamental to the effectiveness of a combat force. This due to the ability of a properly networked force to self-synchronize itself as it engages enemy forces. The purposeful arrangement of assets in a combat force is what makes it 'properly networked'. What is a purposeful arrangement of combat assets? How should a force organize to enhance information sharing and connectivity? And how does connectivity within …


Examining Combat Effectiveness In Asymmetric Engagements With Balanced Forces Using The Information Age Combat Model, Nevan E. N. Shearer Apr 2012

Examining Combat Effectiveness In Asymmetric Engagements With Balanced Forces Using The Information Age Combat Model, Nevan E. N. Shearer

Engineering Management & Systems Engineering Theses & Dissertations

With advances in networked communications, the capabilities of command and control (C2) have come to play an increasingly larger role in battlefield success. Within the past two decades a new military strategy has evolved, known as Network-Centric Operations (NCO), which puts information superiority on the frontline. Moreover, the information advantage that is gained through information superiority is translated into a tactical war-fighting advantage.

A research gap has been identified in the investigation of networked combat force configurations in the realm of asymmetric engagements. Specifically, the research question is, how should an information age combat force be networked in order to …


Agile Knowledge Management; A Review, Reconceptualization, And Extension To Military Applications, Dogan Ozturk Apr 2012

Agile Knowledge Management; A Review, Reconceptualization, And Extension To Military Applications, Dogan Ozturk

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this research is to explore the conceptual background of agility in knowledge management, re-conceptualize it and extend it to military applications with a special focus on Counterinsurgency (COIN).

An initial qualitative exploration of agility in knowledge management was performed. Three different concepts and their interrelationships were analyzed: (1) knowledge management, (2) agility in operations, and (3) military organizations in the COIN environment. Findings from this initial qualitative analysis were used to inductively redefine, re-conceptualize and extend the concept of Agile Knowledge Management (AKM), as well as, to compare and adapt the AKM concept to the military environment …


Health Nexus: A Serious Game Prototype For Prevention And Treatment Of Obesity And Diabetes, Joseph C. Miller Apr 2012

Health Nexus: A Serious Game Prototype For Prevention And Treatment Of Obesity And Diabetes, Joseph C. Miller

Computational Modeling & Simulation Engineering Theses & Dissertations

Electronic games are a prevalent phenomenon of American culture and entertainment. Serious games are video games that take advantage of games' intrinsic entertaining and challenging characteristics for serious purposes, such as education, training, advertisement, and political campaigns. A significant number of serious games have been developed for a variety of diverse purposes. The last few years have witnessed the inception and growth of motion sensing technologies for games, including Nintendo Wii, Sony PlayStation Move, and Microsoft Kinect. These motion sensing technologies usually require game players' physical body movement in order to perform and achieve in the games, such as playing …


Combat Identification Of Synthetic Aperture Radar Images Using Contextual Features And Bayesian Belief Networks, John X. Situ Mar 2012

Combat Identification Of Synthetic Aperture Radar Images Using Contextual Features And Bayesian Belief Networks, John X. Situ

Theses and Dissertations

Given the nearly infinite combination of modifications and configurations for weapon systems, no two targets are ever exactly the same. Synthetic Aperture Radar (SAR) imagery and associated High Range Resolution (HRR) profiles of the same target will have different signatures when viewed from different angles. To overcome this challenge, data from a wide range of aspect and depression angles must be used to train pattern recognition algorithms. Alternatively, features invariant to aspect and depression angle must be found. This research uses simple segmentation algorithms and multivariate analysis methods to extract contextual features from SAR imagery. These features used in conjunction …


Streamlining The Change-Over Protocol For The Rpa Mission Intelligence Coordinator By Way Of Situation Awareness Oriented Design And Discrete Event Simulation, John P. Machuca Mar 2012

Streamlining The Change-Over Protocol For The Rpa Mission Intelligence Coordinator By Way Of Situation Awareness Oriented Design And Discrete Event Simulation, John P. Machuca

Theses and Dissertations

Incredible loiter times coupled with the ability to make extremely detailed collections at significant stand-off distances with a relatively expendable platform has made demand for, and diversity of, Remotely Piloted Aircraft (RPA) operations grow at voracious rates. Conversely, financial resources are becoming increasingly constrained. As such, innovators are looking to maximize the effectiveness of existing personnel and assets by considering concepts such as simultaneous Multiple Aircraft Control (MAC) by a single aircrew. Research has identified procedural inefficiencies in current operations as well as substantial impediments to MAC implementation, including dynamic task saturation and communication challenges. An identified inefficiency afflicting both …


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 …


Biodegradation Of Organophosphate Chemical Warfare Agents By Activated Sludge, Steven J. Schuldt Mar 2012

Biodegradation Of Organophosphate Chemical Warfare Agents By Activated Sludge, Steven J. Schuldt

Theses and Dissertations

Organophosphates (OPs) have been widely used as Chemical Warfare Agents (CWAs) as well as pesticides since World War II and still remain a threat to national security. While efforts have been taken at military installations and civilian communities to secure these chemicals and prevent their misuse, a determined adversary could still obtain and deploy them to injure, kill, or instill terror. The lethal properties of this group of compounds are primarily owed to their irreversible inhibition of the enzyme acetyl cholinesterase (AChE) and thus may alter the human nervous system or affect the hormonal balance of children in particular. In …


Binary Classification Of An Unknown Object Through Atmospheric Turbulence Using A Polarimetric Blind-Deconvolution Algorithm Augmented With Adaptive Degree Of Linear Polarization Priors, Mu J. Kim Mar 2012

Binary Classification Of An Unknown Object Through Atmospheric Turbulence Using A Polarimetric Blind-Deconvolution Algorithm Augmented With Adaptive Degree Of Linear Polarization Priors, Mu J. Kim

Theses and Dissertations

This research develops an enhanced material-classification algorithm to discriminate between metals and dielectrics using passive polarimetric imagery degraded by atmospheric turbulence. To improve the performance of the existing technique for near-normal collection geometries, the proposed algorithm adaptively updates the degree of linear polarization (DoLP) priors as more information becomes available about the scene. Three adaptive approaches are presented. The higher-order super-Gaussian method fits the distribution of DoLP estimates with a sum of two super-Gaussian functions to update the priors. The Gaussian method computes the classification threshold value, from which the priors are updated, by fitting the distribution of DoLP estimates …


Timing Variations In A Magnetic Pulse Compression Circuit, Jeremy S. Oliver Mar 2012

Timing Variations In A Magnetic Pulse Compression Circuit, Jeremy S. Oliver

Theses and Dissertations

The magnetic pulse compression (MPC) circuit uses saturable core inductors and capacitors to compress the width of a pulse. This substantially increases the peak power of the initially applied pulse. The saturable inductor exhibits a hysteresis curve behavior. One particular problem with these MPC circuits is timing variances in the pulse rate of the system. This work models the unique characteristics and signatures of the timing variations of magnetic switches and pulse compressors. The hysteresis curve of the saturable inductor was created by using a nonlinear inductor and a nonlinear resistor in parallel as a substitute for saturable inductors. The …


Low Cost, Low Complexity Sensor Design For Non-Cooperative Geolocation Via Received Signal Strength, Michael S. Butler Mar 2012

Low Cost, Low Complexity Sensor Design For Non-Cooperative Geolocation Via Received Signal Strength, Michael S. Butler

Theses and Dissertations

Obtaining accurate non-cooperative geolocation is vital for persistent surveillance of a hostile emitter. Current research for developing a small, cheap and energy efficient sensor network for non-cooperative geolocation measurements via received signal strength (RSS) is limited. Most existing work focuses on simulating a non-cooperative network (NN) and in doing so, simulated models often ignore localization errors caused from the hardware processing raw RSS data and often model environment-dependent errors as random. By comparing real-time measured non-cooperative geolocation data to a simulated system a more accurate model can be developed. This thesis discusses the development and performance of a small, low …


Boundary Layer Measurements In The Trisonic Gas-Dynamics Facility Using Particle Image Velocimetry With Co₂ Seeding, Daniel B. Wolfe Mar 2012

Boundary Layer Measurements In The Trisonic Gas-Dynamics Facility Using Particle Image Velocimetry With Co₂ Seeding, Daniel B. Wolfe

Theses and Dissertations

Particle image velocimetry (PIV) is utilized with solid carbon dioxide (CO2) seeding material to conduct boundary layer measurements in the test section of the Air Force Research Laboratory's Trisonic Gas-dynamics Facility (TGF), which has a 24 inch by 24 inch cross-section. Freestream velocity was set at Mach 0.3, Mach 0.5, or Mach 0.8 while stagnation pressure ranged from 500 to 2400 pounds per square foot (psf). High pressure liquid CO2 was directed through expansion nozzles into shroud tubes which led to solidified particles in the wind tunnel stagnation chamber. Two different sets of shroud tubes were used …


Computational Analysis And Characterization Of Rc-135 External Aerodynamics, Michael G. Chenery Mar 2012

Computational Analysis And Characterization Of Rc-135 External Aerodynamics, Michael G. Chenery

Theses and Dissertations

Both the RC-135V/W Rivet Joint (RJ) and the RC-135U Combat Sent (CS) aircraft are United States Air Force (USAF) electronics reconnaissance platforms. The RJ is the USAF's standard airborne signals intelligence (SIGINT) gathering platform, while the CS is designed to collect technical intelligence on adversary radar emitter systems. Both aircraft are extensively modified C-135's characterized by protruding cheek fairings along the sides of the fuselage forward of the wings as well as the addition of numerous antennas along the top and bottom of the fuselage. The major distinguishing feature between the two variants is the nose radome, wherein the RJ …


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 …


Stabilizing Acetylcholinesterase On Carbon Electrodes Using Peptide Nanotubes To Produce Effective Biosensors, Todd J. Stevens Mar 2012

Stabilizing Acetylcholinesterase On Carbon Electrodes Using Peptide Nanotubes To Produce Effective Biosensors, Todd J. Stevens

Theses and Dissertations

A biosensor for the detection of organophosphates in water was created by immobilizing acetylcholinesterase (AChE) on a carbon screen printed electrode using peptide nanotubes (PNT) and Nafion®. This sensor was used with acetylthiocholine (ASCh) substrate to detect the inhibitory effects of malathion. The stability of the encapsulated enzyme was measured over 50 days of storage at 4°C in a phosphate buffer solution. The oxidation of thiocholine, a product of the enzymatic reaction of ASCh and AChE, was used to measure the activity of the encapsulated enzyme. Cyclic voltammograms were taken in an ASCh and phosphate buffer solution, and the peak …


Computer Aided Multi-Data Fusion Dismount Modeling, Juan L. Morales Mar 2012

Computer Aided Multi-Data Fusion Dismount Modeling, Juan L. Morales

Theses and Dissertations

Recent research efforts strive to address the growing need for dismount surveillance, dismount tracking and characterization. Current work in this area utilizes hyperspectral and multispectral imaging systems to exploit spectral properties in order to detect areas of exposed skin and clothing characteristics. Because of the large bandwidth and high resolution, hyperspectral imaging systems pose great ability to characterize and detect dismounts. A multi-data dismount modeling system where the development and manipulation of dismount models is a necessity. This thesis demonstrates a computer aided multi-data fused dismount model, which facilitates studies of dismount detection, characterization and identification. The system is created …


All Source Sensor Integration Using An Extended Kalman Filter, Timothy R. Penn Mar 2012

All Source Sensor Integration Using An Extended Kalman Filter, Timothy R. Penn

Theses and Dissertations

The global positioning system (GPS) has become an ubiquitous source for navigation in the modern age, especially since the removal of selective availability at the beginning of this century. The utility of the GPS is unmatched, however GPS is not available in all environments. Heavy reliance on GPS for navigation makes the warfighter increasingly vulnerability as modern warfare continues to evolve. This research provides a method for incorporating measurements from a massive variety of sensors to mitigate GPS dependence. The result is the integration of sensor sets that encompass those examined in recent literature as well as some custom navigation …


Using Vft As A Constraint For Goal Programming Models: A Case Study For Turkish Air Force Flying Hour Program, Ahmet Bengoz Mar 2012

Using Vft As A Constraint For Goal Programming Models: A Case Study For Turkish Air Force Flying Hour Program, Ahmet Bengoz

Theses and Dissertations

In its 60-year history, there have been many published documents in the literature about goal programming (GP), but contributions to the literature are still needed. This research intends to add to the literature on goal-programming models by discussing one of the key assumptions of GP regarding linearity, and by discussing some of the issues regarding incommensurability (difference in data types) and weighting. GP requires an interaction between the decision maker (DM) and the analyst to ensure that the model reflects the DM's preferences. However, it may be difficult for them to interact if the mathematical model is very large and …


Nonlinear Dynamic Model-Based Adaptive Control Of A Solenoid-Valve System, Dongbin Lee, C. Nataraj, P. Naseradinmousavi Mar 2012

Nonlinear Dynamic Model-Based Adaptive Control Of A Solenoid-Valve System, Dongbin Lee, C. Nataraj, P. Naseradinmousavi

All Faculty Articles - School of Engineering and Computer Science

In this paper, a nonlinear model-based adaptive control approach is proposed for a solenoid-valve system. The challenge is that solenoids and butterfly valves have uncertainties in multiple parameters in the nonlinear model; various kinds of physical appearance such as size and stroke, dynamic parameters including inertia, damping, and torque coefficients, and operational parameters especially, pipe diameters and flow velocities. These uncertainties are making the system not only difficult to adjust to the environment, but also further complicated to develop the appropriate control approach for meeting the system objectives. The main contribution of this research is the application of adaptive control …


Dc Dielectrophoretic Assisted Anti-Fouling Filtration System, Nathan M. Cohen Mar 2012

Dc Dielectrophoretic Assisted Anti-Fouling Filtration System, Nathan M. Cohen

Master's Theses

Filtration processes, whether on the microfluidic, clinical treatment systems, or industrial scale (e.g., point-of-care diagnostics, dialysis, and biopharmaceutical manufacturing, respectively), are often inseparable from membrane clogging (fouling). As a consequence, most, if not all, filtration systems require frequent maintenance to maintain functionality and efficiency. The thesis of this project hypothesizes that Dielectrophoresis can be combined with standard filtration to reduce filter fouling, extending membrane life, and enabling continuous operation. This project investigates a method to reduce fouling, add specificity and efficiency, and decrease the cost and challenge of filtration based biofluid separations.

To substantiate this thesis, we designed, fabricated, and …


Analysis Of Resource Control In Nondeterministic Mobile Ad Hoc Network Systems : An Unmanned Aerial Vehicle Example, Alex Fleshman Feb 2012

Analysis Of Resource Control In Nondeterministic Mobile Ad Hoc Network Systems : An Unmanned Aerial Vehicle Example, Alex Fleshman

Electrical and Computer Engineering ETDs

This thesis utilized known information about a dynamic graph in which resource needy nodes act as relays for control information to a supplier node in order to characterize system performance and analyze the effects of change on the system. The connectivity, or information sharing, was based on distance and since every node moved around a defined space, the connectivity of the graph changed constantly. Several different controllers and scenarios are investigated in order to extract the uniqueness in each performance curve which created a better understanding of this near nondeterministic system. One such application for this dynamic system is the …


The Mechanical Testing Of Single Nanofiber, Pratik Manohar Dahule Jan 2012

The Mechanical Testing Of Single Nanofiber, Pratik Manohar Dahule

Theses

Polymer nanofibers exhibit properties that make them a favorable material for the development of tissue engineering scaffolds, filtration devices, sensors, and high strength lightweight materials. Perfectly aligned PLLA Nanofibers were fabricated by an electrospinning technique under optimum conditions and the diameter of the electrospun fibers can easily be tailored by adjusting the concentration of the polymer solution. To align the nanofibers, special arrangement was made in terms of two aluminum plates. Good alignment of polymer nanofibers on specimen was confirmed by SEM observation. The effect of different electro-spinning parameters on maximum fiber length, average fiber diameter, diameter uniformity, and fiber …


Influence Of Personality On A Senior Project Combining Innovation And Entrepreneurship, Jinny Rhee, David W. Parent, Clifton M. Oyamot Jan 2012

Influence Of Personality On A Senior Project Combining Innovation And Entrepreneurship, Jinny Rhee, David W. Parent, Clifton M. Oyamot

Faculty Publications

No abstract provided.


How Is M&S Interoperability Different From Other Interoperability Domains?, Andreas Tolk, Saikou Y. Diallo, Jose J. Padilla, Charles D. Turnitsa Jan 2012

How Is M&S Interoperability Different From Other Interoperability Domains?, Andreas Tolk, Saikou Y. Diallo, Jose J. Padilla, Charles D. Turnitsa

Computational Modeling & Simulation Engineering Faculty Publications

During every standard workshop or event, the examples of working interoperability solutions are used to motivate for 'plug and play' standards for M&S as well, like standardized batteries for electronics, or the use of XML to exchange data between heterogeneous systems. While these are successful applications of standards, they are off the mark regarding M&S interoperability. The challenge of M&S is that the product that needs to be made interoperable is not the service or the system alone, but the model behind it as well. The paper shows that the alignment of conceptualizations is the real problem that is not …


Rapid, Large-Scale Production Of Full-Length, Human-Like Monoclonal Antibodies, Christopher M. Warner Jan 2012

Rapid, Large-Scale Production Of Full-Length, Human-Like Monoclonal Antibodies, Christopher M. Warner

KGI Theses and Dissertations

Current recombinant protein production systems require several months to develop. Existing systems fail to provide timely, flexible, and cost-effective therapies to protect against emergency mass-casualty infections or poisonings. As the identity of many new biological threat agents are unlikely to be known in advance, pre-emptive manufacturing and stockpiling of countermeasures cannot be performed. Preparedness for a biological catastrophe requires a radical solution to replace the current slow scale-up and manufacture of lifesaving medical countermeasures. Subunit vaccines and antibody fragments may be produced in bacteria, yeast, plant or insect cells. However, generation of full-length, human like glycosylated antibodies requires mammalian cell …


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.


Program And Proceedings: Nebraska Academy Of Sciences 1880–2012, 132nd Anniversary Year, One Hundred-Twenty-Second Annual Meeting Jan 2012

Program And Proceedings: Nebraska Academy Of Sciences 1880–2012, 132nd Anniversary Year, One Hundred-Twenty-Second Annual Meeting

Nebraska Academy of Sciences: Programs and Proceedings

Program

Applied Science and Technology

Biological and Medical Sciences

Nebraska Wesleyan University Health and Sciences Graduate School Fair

Aeronautics and Space Science, Poster Session

Maiben Memorial Lecture: "The Status of Nebraska's Native Aspen," "Buffalo" Bruce McIntosh, Western Nebraska Resources Council

Aeronautics

Anthropology

Biological and Medical Sciences

Chemistry and Physics

Collegiate Academy: Biology

Collegiate Academy: Chemistry and Physics

Earth Science

History/Philosophy of Science

Junior Academy, Senior High Competition

Teaching of Science and Math

Junior Academy, Junior High Competition


Leveraging Help Requests In Pomdp Intelligent Tutors, Jeremiah Folsom-Kovarik Jan 2012

Leveraging Help Requests In Pomdp Intelligent Tutors, Jeremiah Folsom-Kovarik

Electronic Theses and Dissertations

Intelligent tutoring systems (ITSs) are computer programs that model individual learners and adapt instruction to help each learner differently. One way ITSs differ from human tutors is that few ITSs give learners a way to ask questions. When learners can ask for help, their questions have the potential to improve learning directly and also act as a new source of model data to help the ITS personalize instruction. Inquiry modeling gives ITSs the ability to answer learner questions and refine their learner models with an inexpensive new input channel. In order to support inquiry modeling, an advanced planning formalism is …


Dns In Computer Forensics, Neil F. Wright Jan 2012

Dns In Computer Forensics, Neil F. Wright

Journal of Digital Forensics, Security and Law

The Domain Name Service (DNS) is a critical core component of the global Internet and integral to the majority of corporate intranets. It provides resolution services between the human-readable name-based system addresses and the machine operable Internet Protocol (IP) based addresses required for creating network level connections. Whilst structured as a globally dispersed resilient tree data structure, from the Global and Country Code Top Level Domains (gTLD/ccTLD) down to the individual site and system leaf nodes, it is highly resilient although vulnerable to various attacks, exploits and systematic failures.