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A User-Oriented Network Forensic Analyser: The Design Of A High-Level Protocol Analyser, D Joy, F Li, N L. Clarke, S M. Furnell Jan 2014

A User-Oriented Network Forensic Analyser: The Design Of A High-Level Protocol Analyser, D Joy, F Li, N L. Clarke, S M. Furnell

Australian Digital Forensics Conference

Network forensics is becoming an increasingly important tool in the investigation of cyber and computer-assisted crimes. Unfortunately, whilst much effort has been undertaken in developing computer forensic file system analysers (e.g. Encase and FTK), such focus has not been given to Network Forensic Analysis Tools (NFATs). The single biggest barrier to effective NFATs is the handling of large volumes of low-level traffic and being able to exact and interpret forensic artefacts and their context – for example, being able extract and render application-level objects (such as emails, web pages and documents) from the low-level TCP/IP traffic but also understand how …


Experimental Development Of Advanced Air Filtration Media Based On Electrospun Polymer Fibers, Negar Ghochaghi Jan 2014

Experimental Development Of Advanced Air Filtration Media Based On Electrospun Polymer Fibers, Negar Ghochaghi

Theses and Dissertations

Electrospinning is a process by which polymer fibers can be produced using an electrostatically driven fluid jet. Electrospun fibers can be produced at the micro- or nano-scale and are, therefore, very promising for air filtration applications. However, because electrospun fibers are electrically charged, it is difficult to control the morphology of filtration media. Fiber size, alignment and uniformity are very important factors that affect filter performance. The focus of this project is to understand the relationship between filter morphology and performance and to develop new methods to create filtration media with optimum morphology.

This study is divided into three focus …


Imperfect Situation Analysis: Representing The Role Of Error And Uncertainty In Modeling, Simulation And Analysis, Victor Eaton Middleton Jan 2014

Imperfect Situation Analysis: Representing The Role Of Error And Uncertainty In Modeling, Simulation And Analysis, Victor Eaton Middleton

Browse all Theses and Dissertations

Much of traditional modeling, simulation and analysis (MS&A) is supported by engineering models - deterministic, Newtonian physics-based representations of closed systems. Such approaches are not well-suited to represent the intricacies of human behavior. This research advocates and seeks to articulate the concept of a more human- centric approach to MS& A, one that better represents decision-making and other cognitive aspects of human behavior as well as it does physical activity.

It starts with a view of individuals and groups as complex adaptive systems, which are best represented using agent-based modeling. Representation of human behavior through intelligent agents incorporates models of …


Human Capital Management Within The Federal Government Utilizing Generational Stratification With A Focus On Generation Y, Ian Nathaniel Barford Jan 2014

Human Capital Management Within The Federal Government Utilizing Generational Stratification With A Focus On Generation Y, Ian Nathaniel Barford

Engineering Management & Systems Engineering Theses & Dissertations

With many individuals in the Baby Boomer generation eligible to retire, many open positions will need to be filled by other Baby Boomers, or those from Generation X or Generation Y. Private industry has taken note of this and has been exploring workplace differences between Generation Y, Generation X, and Baby Boomers. Unfortunately for the federal government, data shows Generation Y is also separating; specifically quitting for unknown reasons. Understanding this apparent dichotomy between Generation Y and Generation X and Baby Boomer federal government employees is a current knowledge gap within the federal government's strategic human capital management focus.

From …


Conducting Polymer Nanowires For Multi-Analyte Chemiresistive Sensing, Edward Song Jan 2014

Conducting Polymer Nanowires For Multi-Analyte Chemiresistive Sensing, Edward Song

LSU Doctoral Dissertations

A conducting polymer nanowire-based chemiresistive sensor array was developed for the liquid-phase multi-analyte detection. The ability to distinguish and quantify multiple chemical species with a single sensory device can be useful in many areas including food industry, pollution control, biosensors, and explosives detection. A polyaniline nanowire is a good candidate for use as a chemiresistive sensing material due to its large resistivity change and ease of synthesis. However the two most important issues in chemiresistive sensors are the reproducibility in sensing and the selectivity in chemical species. For improving the reproducibility in polyaniline-based chemiresistive sensing, a self-calibration mechanism was proposed. …


Theoretical And Experimental Investigations To Improve The Performance Of Surface Acoustic Wave (Saw) Biosensors, Mandek Richardson Jan 2014

Theoretical And Experimental Investigations To Improve The Performance Of Surface Acoustic Wave (Saw) Biosensors, Mandek Richardson

USF Tampa Graduate Theses and Dissertations

The objective of this dissertation is to improve the performance of surface acoustic wave (SAW) biosensors for use in point-of-care-testing (POCT) applications. SAW biosensors have the ability to perform fast, accurate detection of an analyte in real time without the use of labels. However, the technology suffers from the inability to differentiate between specific and non-specific binding. Due to this limitation, direct testing of bodily fluids using SAW sensors to accurately determine an analyte's concentration is difficult. In addition, these sensors are challenged by the need to detect small concentrations of a biomarker that are typically required to give a …


Predics: A New Go-Po-Based Ray Launching Simulator For The Calculation Of Electromagnetic Scattering And Rcs From Electrically Large And Complex Structures, Caner Özdemi̇r, Betül Yilmaz, Özkan Kirik Jan 2014

Predics: A New Go-Po-Based Ray Launching Simulator For The Calculation Of Electromagnetic Scattering And Rcs From Electrically Large And Complex Structures, Caner Özdemi̇r, Betül Yilmaz, Özkan Kirik

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we present a new simulator called pRediCS for the calculation of electromagnetic scattering and radar cross-section (RCS) from electrically large and complex targets. The simulator utilizes the geometric optics (GO) theory and launching of electromagnetic rays for tracing and calculating the electric field values as the electromagnetic waves bounce around the target. The physical optics (PO) theory is also exploited to calculate the final scattered electric field by calculating the far-field PO integration along the observation direction. The simulator is first tested with known objects of canonical shapes, whose analytical solutions are available in the literature. Next, …


Control Design And Performance Analysis For Autonomous Formation Flight Experiments, Caleb M. Rice Jan 2014

Control Design And Performance Analysis For Autonomous Formation Flight Experiments, Caleb M. Rice

Graduate Theses, Dissertations, and Problem Reports (ETD)

Autonomous Formation Flight is a key approach for reducing greenhouse gas emissions and managing traffic in future high density airspace. Unmanned Aerial Vehicles (UAV’s) have made it possible for the physical demonstration and validation of autonomous formation flight concepts inexpensively and eliminates the flight risk to human pilots. This thesis discusses the design, implementation, and flight testing of three different formation flight control methods, Proportional Integral and Derivative (PID); Fuzzy Logic (FL); and NonLinear Dynamic Inversion (NLDI), and their respective performance behavior. Experimental results show achievable autonomous formation flight and performance quality with a pair of low-cost unmanned research fixed …


Liquid Core Waveguide Sensors With Single And Multi-Spot Excitation, Lynnell Uilani Wai Yee Zempoaltecatl Dec 2013

Liquid Core Waveguide Sensors With Single And Multi-Spot Excitation, Lynnell Uilani Wai Yee Zempoaltecatl

Theses and Dissertations

Using silicon based microfabrication and materials, a photonic platform, capable of single bioparticle analysis, has been developed. This platform combines liquid and hollow core waveguides on the micron-scale (5 µm x 12 µm) to isolate femtoliter sized sample volumes. Fluorescence excitation and signals in the visible range are directed into and out of the sample volume at an orthogonal angle to maximize signal-to-noise. In order to guide light in a low-index material antiresonant reflecting optical waveguides (ARROWs) were incorporated into the platform. This thesis reveals the development path of these structures over several device generations including innovations in material, geometries, …


Fundamental Experimental Studies In Scaling, Blast Mitigation And Material Processing, Xing Zhao Dec 2013

Fundamental Experimental Studies In Scaling, Blast Mitigation And Material Processing, Xing Zhao

Theses and Dissertations

In this work, two separate research efforts are discussed. They include experimental studies in (1) Scaling and Blast Mitigation and (2) Scaling in Friction Stir Extrusion. In both studies, the primary experimental measurement method is three-dimensional digital image correlation (3D-DIC), a non-contacting full-field measurement method that is applicable for both high-rate loading and quasi-static loading conditions.

Scaling and Blast Mitigation Studies:

A series of properly scaled structures was subjected to buried blast loading conditions via detonation of a small explosive buried in saturated sand. Using high speed stereo-vision systems to record the deformations of selected regions on the upper surface …


Chipless Rfid Tags Based On Multiple Band-Rejected Planar Log-Periodic Antennas, Shulabh Gupta, Li (Lijun) Jun Jiang Dec 2013

Chipless Rfid Tags Based On Multiple Band-Rejected Planar Log-Periodic Antennas, Shulabh Gupta, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

A passive chipless Radio-frequency identification (RFID) tag is proposed based on the tailorable band-rejection property of the log-periodic (LP) antennas. The proposed tag principle is successfully demonstrated using full-wave simulations, where the absence and presence of the band-rejection in VSWR and thus radiation gain, is shown to carry the bit information. Due to the large number of dipole radiators on the LP aperture, the proposed tag can easily support large number of codes, providing a potential solution for limited number of bits in conventional chipless tags. © 2013 IEEE.


Synthesis And Characterization Of Multi-Component Enrichment Polymer Layers For Chemical Sensor Applications, James Giammarco Dec 2013

Synthesis And Characterization Of Multi-Component Enrichment Polymer Layers For Chemical Sensor Applications, James Giammarco

All Dissertations

This dissertation presents the building and study of a "universal" enrichment polymer layer system (EPLS). Thin polymer films have been utilized as enrichment layers for evanescent waveguide chemical sensors. The chemical nature of the polymer provides affinity which promotes the analyte to be absorbed. Having one highly sensitive polymer layer is suitable for a single target volatile organic compound (VOC). Here, the development of multi-layered and multi-component thin polymer films has been done to allow for more diverse affinity. Several parameters were identified to make the EPLSs suitable as enrichment layers for chemical sensor devices. The evanescent sensor devices used …


Aerodynamic Performance And Particle Image Velocimetery Of Piezo Actuated Biomimetic Manduca Sexta Engineered Wings Towards The Design And Application Of A Flapping Wing Flight Vehicle, Anthony M. Deluca Dec 2013

Aerodynamic Performance And Particle Image Velocimetery Of Piezo Actuated Biomimetic Manduca Sexta Engineered Wings Towards The Design And Application Of A Flapping Wing Flight Vehicle, Anthony M. Deluca

Theses and Dissertations

Considerable research and investigation has been conducted on the aerodynamic performance, and the predominate flow physics of the Manduca sexta size of biomimetically designed and fabricated wings as part of the AFIT FWMAV design project. Despite a burgeoning interest and research into the diverse field of flapping wing flight and biomimicry, the aerodynamics of flapping wing flight remains a nebulous field of science with considerable variance into the theoretical abstractions surrounding aerodynamic mechanisms responsible for aerial performance. Traditional FWMAV flight models assume a form of a quasi-steady approximation of wing aerodynamics based on an infinite wing element model (BEM). An …


Trajectory Generation And Optimization For Experimental Investigation Of Flapping Flight, Michael Schnebly Wilcox Nov 2013

Trajectory Generation And Optimization For Experimental Investigation Of Flapping Flight, Michael Schnebly Wilcox

Theses and Dissertations

Though still in relative infancy, the field of flapping flight has potential to have a far-reaching impact on human life. Nature presents a myriad of examples of successful uses of this locomotion. Human efforts in flapping flight have seen substantial improvement in recent times. Wing kinematics are a key aspect of this study. This study summarizes previous wing trajectory generators and presents a new trajectory generation method built upon previous methods. This includes a novel means of commanding unequal half-stroke durations subject to robotic trajectory continuity requirements. Additionally, previous optimization methods are improved upon. Experimental optimization is performed using the …


Deployed Communications In An Austere Environment: A Delphi Study, Andrew Soine, James Harker, Alan R. Heminger Nov 2013

Deployed Communications In An Austere Environment: A Delphi Study, Andrew Soine, James Harker, Alan R. Heminger

Faculty Publications

The information and communications technology (ICT) field is undergoing a period of tremendous change. The exponential growth rate of ICT capability in recent decades, which has had an undeniable effect on every aspect of our society, will likely have ramifications for military operations in austere environments. 1 The Air Force’s 689th Combat Communications Wing commissioned a study to forecast the future of mobile ICT in such environments. Researchers at the Air Force Institute of Technology chose to employ the Delphi technique as the methodology for executing this task. The following scenario, based on the results of that study, demonstrates how …


Performance Guarantees For C-Wmd Robot Missions, Shu Jiang, Ronald C. Arkin, Damian M. Lyons, Tsung-Ming Liu, Dagon Harrington Oct 2013

Performance Guarantees For C-Wmd Robot Missions, Shu Jiang, Ronald C. Arkin, Damian M. Lyons, Tsung-Ming Liu, Dagon Harrington

Faculty Publications

Robotics has been considered as one of the five key technology areas for defense against attacks with weapons of mass destruction (WMD). However, due to the mass impact nature of WMD, failures of counter-WMD (C-WMD) missions can have catastrophic consequences.To ensure robot's success in carrying out C-WMD missions, we have developed a novel verification framework in providing performance guarantees for behavior-based and probabilistic robot algorithms in complex real-world environments. This paper describes the system architecture and discusses how the verification framework can be used to provide pre-mission performance guarantees for robots in executing C-WMD missions.


High-Power Microwave/ Radio-Frequency Components, Circuits, And Subsystems For Next-Generation Wireless Radio Front-Ends, Kenle Chen Oct 2013

High-Power Microwave/ Radio-Frequency Components, Circuits, And Subsystems For Next-Generation Wireless Radio Front-Ends, Kenle Chen

Open Access Dissertations

As the wireless communication systems evolve toward the future generation, intelligence will be the main signature/trend, well known as the concepts of cognitive and software-defined radios which offer ultimate data transmission speed, spectrum access, and user capacity. During this evolution, the human society may experience another round of `information revolution'. However, one of the major bottlenecks of this promotion lies in hardware realization, since all the aforementioned intelligent systems are required to cover a broad frequency range to support multiple communication bands and dissimilar standards. As the essential part of the hardware, power amplifiers (PAs) capable of operating over a …


Terrain Following In Unmanned Air Vehicles Using Optic Flow Sensors, Blake Barber, Dr. Tim Mclain Sep 2013

Terrain Following In Unmanned Air Vehicles Using Optic Flow Sensors, Blake Barber, Dr. Tim Mclain

Journal of Undergraduate Research

A key enabling technology that will allow the U.S. Military to maintain information superiority in the 21st century is the development and implementation of Unmanned Air Vehicle (UAV) technology. Especially critical to the support of the small special operations units conducting the asymmetric warfare of the 21st century will be the development of mini and micro UAV technology. Mini and micro UAV technology will enable foot soldiers to hand launch and recover small, robust reconnaissance aircraft capable of providing real-time video surveillance and real-time target acquisition. These capabilities will allow soldiers to have the full situational awareness they need for …


Real-Time Path Planning For Unmanned Air Vehicles, Andrew Curtis, Dr. Randal Beard Sep 2013

Real-Time Path Planning For Unmanned Air Vehicles, Andrew Curtis, Dr. Randal Beard

Journal of Undergraduate Research

Unmanned Air Vehicles (UAVs) have become an important research topic in recent years. Military and civilian groups desire to use UAVs for several purposes, including surveillance, search and rescue, communications relays, and warfare. In the MAGICC Lab at BYU, we are researching low-cost methods of using miniature UAVs (wingspan of less than 2 meters) for these applications. We have developed a small autopilot to fly these UAVs and are able to give them commands by wireless communication from a laptop that is used as a ground station. With this research platform, we are able to easily test our methods and …


Radio Frequency Based Programmable Logic Controller Anomaly Detection, Samuel J. Stone Sep 2013

Radio Frequency Based Programmable Logic Controller Anomaly Detection, Samuel J. Stone

Theses and Dissertations

The research goal involved developing improved methods for securing Programmable Logic Controller (PLC) devices against unauthorized entry and mitigating the risk of Supervisory Control and Data Acquisition (SCADA) attack by detecting malicious software and/or trojan hardware. A Correlation Based Anomaly Detection (CBAD) process was developed to enable 1) software anomaly detection discriminating between various operating conditions to detect malfunctioning or malicious software, firmware, etc., and 2) hardware component discrimination discriminating between various hardware components to detect malfunctioning or counterfeit, trojan, etc., components.


An Analysis Of Eliminating Electroosmotic Flow In A Microfluidic Pdms Chip, Cecile D. Redington Sep 2013

An Analysis Of Eliminating Electroosmotic Flow In A Microfluidic Pdms Chip, Cecile D. Redington

Master's Theses

The goal of this project is to eliminate electroosmotic flow (EOF) in a microfluidic chip. EOF is a naturally occurring phenomenon at the fluid-surface interface in microfluidic chips when an electric field is applied across the fluid. When isoelectric focusing (IEF) is carried out to separate proteins based on their surface charge, the analytes must remain in the separation chamber, and not migrate to adjacent features in the microfluidic chip, which happens with EOF.

For this project, a microfluidic chip was designed and commissioned to be photolithographically transferred onto a Si wafer. A PDMS component was then casted on the …


Public Perception Of Unmanned Aerial Systems (Uas): A Survey Of Public Knowledge Regarding Roles, Capabilities, And Safety While Operating Within The National Airspace System (Nas), Dennis Vincenzi, David Ison, Dahai Liu Aug 2013

Public Perception Of Unmanned Aerial Systems (Uas): A Survey Of Public Knowledge Regarding Roles, Capabilities, And Safety While Operating Within The National Airspace System (Nas), Dennis Vincenzi, David Ison, Dahai Liu

Publications

A variety of challenges to the successful assimilation of Unmanned Aircraft Systems (UASs) into the National Airspace System (NAS) exists. Aside from technical and legislative challenges, another setback has recently surfaced when the FAA suspended its selection process for UAS test sites due to privacy concerns. This new obstacle has the potential to further delay UAS integration. Very little literature or coverage of UAS domestic operations and accidents have been published and made available to the public at large. As a result, the public has very little information upon which to form any realistic or reasonable opinions concerning the integration …


Novel Side-Vent-Channel Based Blast Mitigation Concept For Light Tactical Vehicles, Ramin Yavari Aug 2013

Novel Side-Vent-Channel Based Blast Mitigation Concept For Light Tactical Vehicles, Ramin Yavari

All Theses

A new concept solution for improving survivability of the light tactical military vehicles to blast-loads resulting from a shallow-buried mine detonated underneath such vehicles is proposed and critically assessed using computational engineering methods and tools. The solution is inspired by the principle of operation of the rocket-engine nozzles, in general and the so called 'pulse detonation' rocket engines, in particular, and is an extension of the recently introduced so-called 'blast chimney' concept (essentially a vertical channel connecting the bottom and the roof and passing through the cabin of a light tactical vehicle).
Relative to the blast-chimney concept, the new solution …


Pan Nanofibers And Nanofiber Reinforced Composites, Cheng Ren Aug 2013

Pan Nanofibers And Nanofiber Reinforced Composites, Cheng Ren

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Nanomaterials play an important role in the development of nanotechnology. They possess unique mechanical, physical, and chemical properties coupled with small size and ultrahigh surface area that can provide critical advantages for applications. Continuous nanofibers attract special interest due to their dual nano-macro nature and ability to bridge scales. Nanofibers are being considered for a broad range of applications spanning advanced filters, separation membranes, ultrasensitive sensors, micro/nano actuators, nanoprobes, tissue engineering scaffolds, protective and smart closing, and multifunctional composites. Most of these applications require certain mechanical properties and robustness. However, the literature on the mechanical behavior of nanofibers and their …


More Effective Human Spaceflight Programs And Their International Security Implications, Bert Chapman, Sarag J. Saikia Jul 2013

More Effective Human Spaceflight Programs And Their International Security Implications, Bert Chapman, Sarag J. Saikia

Libraries Faculty and Staff Scholarship and Research

NASA can more effectively perform its missions by transferring its aeronautic responsibilities to the Federal Aviation Administration and be renamed the National Space Agency. The U.S. must also recognize that space is an emerging arena of international competition and conflict and militarily protect its space assets from China which seeks to use space to restrict the U.S.' ability to defend its strategic interests in regions such as the Western Pacific.


A Multi-Scale Approach To A Greater Understanding Of The Behavior Of Heterogeneous Materials Under Dynamic Loading, Andrew J. Van Vooren Jul 2013

A Multi-Scale Approach To A Greater Understanding Of The Behavior Of Heterogeneous Materials Under Dynamic Loading, Andrew J. Van Vooren

Master's Theses (2009 -)

The penetration of granular materials is of interest to a variety of different fields, and is an active area of research. The objective of this project is to gain understanding of the dynamics of a projectile penetrating into a granular material. To do this, experiments were run and a numerical model was created.

A dart gun was used to accelerate an aluminum dart to velocities around 100 m/s, which then impacted a target tank filled with Ottawa sand. The dart flew along a view window, which allowed for a recording of the penetration event using a high speed camera. Pressure …


Evaluation Of Cyber Sensors For Enhancing Situational Awareness In The Ics Environment, Jeremy R. Otis Jun 2013

Evaluation Of Cyber Sensors For Enhancing Situational Awareness In The Ics Environment, Jeremy R. Otis

Theses and Dissertations

Industrial Control Systems (ICS) monitor and control operations associated with the national critical infrastructure (e.g., electric power grid, oil and gas pipelines and water treatment facilities). These systems rely on technologies and architectures that were designed for system reliability and availability. Security associated with ICS was never an inherent concern, primarily due to the protections afforded by network isolation. However, a trend in ICS operations is to migrate to commercial networks via TCP/IP in order to leverage commodity benefits and cost savings. As a result, system vulnerabilities are now exposed to the online community. Indeed, recent research has demonstrated that …


Applied Hypergame Theory For Network Defense, Alan S. Gibson Jun 2013

Applied Hypergame Theory For Network Defense, Alan S. Gibson

Theses and Dissertations

Cyber operations are the most important aspect of military conflicts in the 21st century, but unfortunately they are also among the least understood. The continual battle for network dominance between attackers and defenders is considered to be a complex game. Hypergame theory is an extension of game theory that addresses the kind of games where misperception exists, as is often the case in military engagements. Hypergame theory, like game theory, uses a game model to determine strategy selection, but goes beyond game theory by examining subgames that exist within the full game. The inclusion of misperception and misinformation in the …


Wireless Impact Detection System, Shawno Auwae, Kyle Terriere Jun 2013

Wireless Impact Detection System, Shawno Auwae, Kyle Terriere

Interdisciplinary Design Senior Theses

Recently, brain trauma caused by multiple concussions has become a pressing issue for contact sports, mainly American football players. The severity of the impacts in these sports have led to discussion concerning the standard safety equipment used, as well as the rules enforcing a certain style of play. Multiple studies have shown that concussions have damaging long-term effects, including dementia and memory loss. The dominant professional football organization, the National Football League (NFL), employs qualified athletic trainers to diagnose and treat players with concussions, but many incidents still go undetected. This problem is magnified at the youth level, where the …


Spread Spectrum Jamming - Part 2, Casey Burke, Christian Hume, Javier Meza Jun 2013

Spread Spectrum Jamming - Part 2, Casey Burke, Christian Hume, Javier Meza

Electrical Engineering

Direct-sequence spread spectrum (DSSS) is a special modulation technique used in many telecommunication devices which uses a wide bandwidth relative to single-frequency carrier modulation techniques. Like the name suggests, the spectral content of wireless signals are spread across a range of frequencies to increase the security of transmitted signals by reducing the potential impact of outside interference (i.e. noise, jamming). This resistance against outside interference and jamming has particular application in the field of electronic warfare where spread spectrum jamming techniques may prove to be an effective way of shutting down remotely controlled enemy vehicles.

Last year, a group of …