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Full-Text Articles in Engineering

Improving The Quality Of Service And Security Of Military Networks With A Network Tasking Order Process, Matthew D. Compton Sep 2010

Improving The Quality Of Service And Security Of Military Networks With A Network Tasking Order Process, Matthew D. Compton

Theses and Dissertations

This research presents a Network Tasking Order process that collects mission plans, network capabilities, and historical records to build a Network Tasking Order (NTO). The NTO document directs the form and usage of the network, much like an Air Tasking Order (ATO) directs the usage of air power. The NTO process is fleshed out with the content and format of the NTO given herein for the first time. Tools such as topology control algorithms are then shown through simulation to improve the quality of service of the network by finding favorable ways to connect the assets identified during the NTO …


Improving Range Estimation Of A 3d Flash Ladar Via Blind Deconvolution, Jason R. Mcmahon Sep 2010

Improving Range Estimation Of A 3d Flash Ladar Via Blind Deconvolution, Jason R. Mcmahon

Theses and Dissertations

The purpose of this research effort is to improve and characterize range estimation in a three-dimensional FLASH LAser Detection And Ranging (3D FLASH LADAR) by investigating spatial dimension blurring effects. The myriad of emerging applications for 3D FLASH LADAR both as primary and supplemental sensor necessitate superior performance including accurate range estimates. Along with range information, this sensor also provides an imaging or laser vision capability. Consequently, accurate range estimates would also greatly aid in image quality of a target or remote scene under interrogation. Unlike previous efforts, this research accounts for pixel coupling by defining the range image mathematical …


Determining The Index Of Refraction Of An Unknown Object Using Passive Polarimetric Imagery Degraded By Atmospheric Turbulence, Milo W. Hyde Iv Sep 2010

Determining The Index Of Refraction Of An Unknown Object Using Passive Polarimetric Imagery Degraded By Atmospheric Turbulence, Milo W. Hyde Iv

Theses and Dissertations

In this research, an algorithm is developed to estimate the index of refraction of an unknown object using passive polarimetric images degraded by atmospheric turbulence. The algorithm uses a variant of the maximum-likelihood blind-deconvolution algorithm developed by LeMaster and Cain to recover the true object (i.e., the first Stokes parameter), the degree of linear polarization, and the polarimetric-image point spread functions. Nonlinear least squares is then used to find the value of the complex index of refraction which best fits the theoretical degree of linear polarization, derived using a polarimetric bidirectional reflectance distribution function, to the turbulence-corrected degree of linear …


Hijacking User Uploads To Online Persistent Data Repositories For Covert Data Exfiltration, Curtis P. Barnard Sep 2010

Hijacking User Uploads To Online Persistent Data Repositories For Covert Data Exfiltration, Curtis P. Barnard

Theses and Dissertations

As malware has evolved over the years, it has gone from harmless programs that copy themselves into other executables to modern day botnets that perform bank fraud and identity theft. Modern malware often has a need to communicate back to the author, or other machines that are also infected. Several techniques for transmitting this data covertly have been developed over the years which vary significantly in their level of sophistication. This research creates a new covert channel technique for stealing information from a network by piggybacking on user-generated network traffic. Specifically, steganography drop boxes and passive covert channels are merged …


Orbital Tori Construction Using Trajectory Following Spectral Methods, Ralph E. Bordner Iii Sep 2010

Orbital Tori Construction Using Trajectory Following Spectral Methods, Ralph E. Bordner Iii

Theses and Dissertations

By assuming the motion of a satellite about the earth’s geopotential mimics the known Kolmogorov-Arnold-Moser (KAM) solution of a lightly perturbed integrable Hamiltonian system, this research focused on applying trajectory following spectral methods to estimate orbital tori from sampled orbital data. From an estimated basis frequency set, orbital data was decomposed into multi-periodic Fourier series, essentially compressing ephemerides for long-term use. Real-world Global Positioning System (GPS) orbital tracks were decomposed and reconstructed with error from as low as few kilometers per coordinate axis over a 10-week span to tens of kilometers per coordinate axis over the same time period, depending …


Providing A Theoretical Basis For Nanotoxicity Risk Analysis Departing From Traditional Physiologically-Based Pharmacokinetic (Pbpk) Modeling, Dirk P. Yamamoto Sep 2010

Providing A Theoretical Basis For Nanotoxicity Risk Analysis Departing From Traditional Physiologically-Based Pharmacokinetic (Pbpk) Modeling, Dirk P. Yamamoto

Theses and Dissertations

The same novel properties of engineered nanoparticles that make them attractive may also present unique exposure risks. But, the traditional physiologically-based pharmacokinetic (PBPK) modeling assumption of instantaneous equilibration likely does not apply to nanoparticles. This simulation-based research begins with development of a model that includes diffusion, active transport, and carrier mediated transport. An eigenvalue analysis methodology was developed to examine model behavior to focus future research. Simulations using the physicochemical properties of size, shape, surface coating, and surface charge were performed and an equation was determined which estimates area under the curve for arterial blood concentration, which is a surrogate …


Exploring The Effects Of International Traffic In Arms Regulations Restrictions On Innovation In The U.S. Space Industrial Base, Kalliroi L. Landry Sep 2010

Exploring The Effects Of International Traffic In Arms Regulations Restrictions On Innovation In The U.S. Space Industrial Base, Kalliroi L. Landry

Theses and Dissertations

The International Traffic in Arms Regulations (ITAR) are used to protect United States (U.S.) military technologies. However, changes to ITAR export controls regarding space technologies have had a major impact to the U.S. space industry. The literature mentions a concern for the health of lower-tier firms because they are a major source of innovation, but there is no additional information considering the effects of ITAR on space innovation at those lower tiers. The purpose of this thesis was to explore the implications of continuing the current ITAR restrictions with regard to innovation in the space industry. This research used a …


Knowledge-Based Decision Support In Department Of Defense Acquisitions, Clifton L. Hicks Sep 2010

Knowledge-Based Decision Support In Department Of Defense Acquisitions, Clifton L. Hicks

Theses and Dissertations

Despite numerous reform efforts over the past 30 years, acquisition programs in the Department of Defense (DoD) continue to experience cost overruns and schedule delays. One contributing factor is the decision-making process used by defense officials. The General Accounting Office (GAO) has stated that ‘poor program outcomes are the lack of widespread adoption of a knowledge-based acquisition process within DoD despite polices that support such a process. A knowledge-based business case at the outset of each program would alleviate overpromising on cost, schedule, and performance and would empower program managers.’ Effective decision-making for acquisition programs is very important. It not …


Satellite Capabilities Mapping - Utilizing Small Satellites, David A. Grigsby Sep 2010

Satellite Capabilities Mapping - Utilizing Small Satellites, David A. Grigsby

Theses and Dissertations

The cost and schedule advantages small satellites have over larger legacy systems have been studied, but there has been very little experimentation performed to determine whether small satellites can actually deliver the capabilities of larger spacecraft. To date, a desired operational capability has not been fully realized by a scalable satellite design. Advances in sensor technology have led to significant reductions in size, weight, and power (SWaP) presenting an opportunity to exploit the evolution of space operations by using small satellites to perform specific missions. This paper describes a methodology that maps a specific set of large space vehicle capabilities …


Analysis Of Construction-Related Research Compared To Needs Of Industry Professionals, Sterling Graham Sep 2010

Analysis Of Construction-Related Research Compared To Needs Of Industry Professionals, Sterling Graham

Theses and Dissertations

Research plays a large role in the advancement of any industry. It is particularly important that relevant research is performed in an industry as large and critical as the construction industry. A review of literature shows that historically research has not played a major role in the advancement of the construction industry. The work of this thesis was to explore whether there has been a change in this relationship, or not. This thesis explored whether the construction-related research being done is in alignment with the needs of industry. Comparisons of the rankings of construction research and industry views were done …


Applying Image Matching To Video Analysis, Adam J. Behring Sep 2010

Applying Image Matching To Video Analysis, Adam J. Behring

Theses and Dissertations

Dealing with the volume of multimedia collected on a daily basis for intelligence gathering and digital forensics investigations requires significant manual analysis. A component of this problem is that a video may be reanalyzed that has already been analyzed. Identifying duplicate video sequences is difficult due to differences in videos of varying quality and size. This research uses a kd-tree structure to increase image matching speed. Keypoints are generated and added to a kd-tree of a large dimensionality (128 dimensions). All of the keypoints for the set of images are used to construct a global kd-tree, which allows nearest neighbor …


Analysis Of Alternative Methods For Long-Term Wind Speed And Initial Site Assessment For Purposes Of Wind Energy Production Estimation, Ryan Mcdevitt Sep 2010

Analysis Of Alternative Methods For Long-Term Wind Speed And Initial Site Assessment For Purposes Of Wind Energy Production Estimation, Ryan Mcdevitt

Theses and Dissertations

A need exists for identification and evaluation of viable sites for wind energy. However, this is made difficult by the site-specific nature of the wind. A review of current industry practices shows that linear regression is the preferred method, although little work has been done to investigate alternative approaches. To address this, various methods were tested on 23 target sites with data measured over a long-term period. Each site was analyzed with the chosen best reference station, across 10 data periods for each method with results classified as mean absolute percentage error in energy density between the projected and measured …


Defect Detection Microscopy, Stuart Craig Rogers Sep 2010

Defect Detection Microscopy, Stuart Craig Rogers

Theses and Dissertations

The automotive industry's search for stronger lighter materials has been hampered in its desire to make greater use of Magnesium alloys by their poor formability below 150°C. One current challenge is to identify the complex structure and deformation mechanisms at work and determine which of these are primary contributors to the nucleation of defects. Orientation Imaging Microscopy has been the most accessible tool for microstructural analysis over the past 15 years. However, using OIM to analyze defect nucleation sites requires prior knowledge of where the defects will occur because once the defects nucleate the majority of microstructural information is destroyed. …


All Solid-State Mid-Ir Laser Development, Nonlinear Absorption Investigation And Laser-Induced Damage Study, Torrey J. Wagner Sep 2010

All Solid-State Mid-Ir Laser Development, Nonlinear Absorption Investigation And Laser-Induced Damage Study, Torrey J. Wagner

Theses and Dissertations

In this research, nonlinear optical absorption coefficients and laser-induced damage thresholds are measured in Ge and GaSb, which are materials that are used in IR detectors. Using a simultaneous fitting technique to extract nonlinear absorption coefficients from data at two pulse widths, two-photon and free-carrier absorption coefficients are measured in Ge and GaSb at 2.05 and 2.5 μm for the first time. At these wavelengths, nonlinear absorption is the primary damage mechanism, and damage thresholds at picosecond and nanosecond pulse widths were measured and agreed well with modeled thresholds using experimentally measured parameters. The damage threshold for a single-layer Al …


Development Of A Pseudo-Uniform Structural Velocity Metric For Use In Active Structural Acoustic Control, Jeffery M. Fisher Aug 2010

Development Of A Pseudo-Uniform Structural Velocity Metric For Use In Active Structural Acoustic Control, Jeffery M. Fisher

Theses and Dissertations

Active control of sound and vibration fields has become an strong area of research over the past few decades. In regards to the active control of acoustic radiation from vibration fields, known as active structural acoustic control (ASAC), there have been many different methods employed to understand structural and acoustic relationships and to control vibrations to limit the acoustic radiation. With active sound field control, sensors, usually microphones, need to be dispersed in the sound field, or an array of microphones must be placed directly in the sound field which, in many cases, uses up too much space for practical …


In Vitro Evaluation Of Mechanical Heart Valve Performance Using A Novel Test Chamber In An Automated Mock Circulatory Loop, Antonio Walker Aug 2010

In Vitro Evaluation Of Mechanical Heart Valve Performance Using A Novel Test Chamber In An Automated Mock Circulatory Loop, Antonio Walker

Theses and Dissertations

Valvular heart disease (VHD) continues to have significant effects on many people’s lives, with numbers expected to grow tremendously over the next few years. Individuals suffering from severe valvular heart disease usually require a heart valve transplant in order to restore the native valve’s vital unidirectional flow regulation. Therefore, artificial heart valve (AHV) research is of very high importance. Previous research studies have provided substantial input in the realm of AHV design relative to durability, thrombotic and hemolytic potential, and overall functionality. However, modifications continue to be warranted due to limitations in the accuracy and time efficiency of the in …


Confining An Organic Molecule In A Nanocavity: Effect On Rotational/Vibrational Motion And Its Consequence For Spin Dephasing., Lopamudra Das Aug 2010

Confining An Organic Molecule In A Nanocavity: Effect On Rotational/Vibrational Motion And Its Consequence For Spin Dephasing., Lopamudra Das

Theses and Dissertations

Recently, it was found that the strongly temperature-dependent spin dephasing time of bound electrons in the organic molecule tris(8-hydroxyquinoline aluminum), or Alq3, increases when a few of these molecules are confined within 1-2 nm sized nanocavities in porous alumina. What causes this increase is not well understood, but one possibility is that the rotational/vibrational modes of the molecule are altered inside a nanocavity, leading to suppression of spin coupling with these modes and a concomitant increase in the spin dephasing time. To test this possibility, we have carried out mid-infrared spectroscopy of few molecule clusters confined within 1-2 nm sized …


Comparison Of Winter Temperature Profiles In Asphalt And Concrete Pavements, Jeremy Brooks Dye Aug 2010

Comparison Of Winter Temperature Profiles In Asphalt And Concrete Pavements, Jeremy Brooks Dye

Theses and Dissertations

Because winter maintenance is so costly, Utah Department of Transportation (UDOT) personnel asked researchers at Brigham Young University to determine whether asphalt or concrete pavements require more winter maintenance. Differing thermal properties suggest that, for the same environmental conditions, asphalt and concrete pavements will have different temperature profiles. Climatological data from 22 environmental sensor stations (ESSs) near asphalt roads and nine ESSs near concrete roads were used to 1) determine which pavement type has higher surface temperatures in winter and 2) compare the subsurface temperatures under asphalt and concrete pavements to determine the pavement type below which more freeze-thaw cycles …


Influence Of Relative Compaction On Passive Resistance Of Abutments With Mechanically Stabilized Earth (Mse) Wingwalls, Alec N. Strassburg Aug 2010

Influence Of Relative Compaction On Passive Resistance Of Abutments With Mechanically Stabilized Earth (Mse) Wingwalls, Alec N. Strassburg

Theses and Dissertations

Large scale static lateral load tests were completed on a pile cap with wingwalls under several different sand backfill configurations: no backfill, loosely compacted unconfined, loosely compacted slip plane wall confined, loosely compacted MSE wingwall confined, and densely compacted MSE wingwall confined. The relative compaction of the backfill was varied during each test to observe the change in passive resistance provided by the backfill. The wall types were varied to observe the force placed on the walls and the wall displacement as a result of the laterally loaded pile cap and backfill relative compaction. Passive force-displacement curves were generated from …


Low-Loss Hollow Waveguide Platforms For Optical Sensing And Manipulation, Evan J. Lunt Aug 2010

Low-Loss Hollow Waveguide Platforms For Optical Sensing And Manipulation, Evan J. Lunt

Theses and Dissertations

This dissertation presents a method for fabricating integrated hollow and solid optical waveguides on planar substrates. These waveguides are antiresonant reflecting optical waveguides (ARROWs), where high-index cladding layers confine light to hollow cores through optical interference. Hollow waveguides that can be filled with liquids or gases are an important new building block for creating highly-integrated optical sensors. The method developed for fabricating these integrated waveguides employs standard processes and materials used in the microelectronics industry, allowing for parallel, low-cost fabrication. Dielectric cladding layers are deposited on a silicon wafer using plasma-enhanced chemical vapor deposition (PECVD). After the lower cladding layers …


Image Processing Algorithms For Diagnostic Analysis Of Microcirculation, Sumeyra Ummuhan Demir Aug 2010

Image Processing Algorithms For Diagnostic Analysis Of Microcirculation, Sumeyra Ummuhan Demir

Theses and Dissertations

Microcirculation has become a key factor for the study and assessment of tissue perfusion and oxygenation. Detection and assessment of the microvasculature using videomicroscopy from the oral mucosa provides a metric on the density of blood vessels in each single frame. Information pertaining to the density of these microvessels within a field of view can be used to quantitatively monitor and assess the changes occurring in tissue oxygenation and perfusion over time. Automated analysis of this information can be used for real-time diagnostic and therapeutic planning of a number of clinical applications including resuscitation. The objective of this study is …


Development Of A Low Cost Autopilot System For Unmanned Aerial Vehicles, Jose Ortiz Aug 2010

Development Of A Low Cost Autopilot System For Unmanned Aerial Vehicles, Jose Ortiz

Theses and Dissertations

The purpose of this thesis was to develop a low cost autonomous flight control system for small unmanned aerial vehicles with the aim to support collaborative systems. A low cost hardware solution was achieved by careful selection of sensors, integration of hardware subsystems, and the use of new microcontroller technologies. Flight control algorithms to guide a vehicle though waypoint based flight paths and loiter about a point were implemented using direction fields. A hardware in the loop simulator was developed to ensure proper operation of all hardware and software components prior to flight testing. The resulting flight control system achieved …


Quantitative And Qualitative Results From Droplet Impingement Experiments On Superhydrophobic Surfaces With Micro-Ribs For Three Liquid Types, John T. Pearson Aug 2010

Quantitative And Qualitative Results From Droplet Impingement Experiments On Superhydrophobic Surfaces With Micro-Ribs For Three Liquid Types, John T. Pearson

Theses and Dissertations

Experiments were performed in which liquid droplets were videographically recorded impacting horizontal superhydrophobic surfaces. The superhydrophobic surfaces were micropatterned with alternating ribs and cavities and coated with a hydrophobic coating. The following surface types were also tested for comparison: smooth uncoated, micropatterned uncoated, and smooth coated surfaces. Three liquid types were used: pure water, ethanol, and a 50/50 water/glycerine mixture. Acquired data demonstrated that the maximum droplet spread diameter exhibited a greater Weber number dependence than that previously reported in the literature. The time delays between impact and maximum spread and between impact and ejection of a vertical jet were …


Thin Film Microfluidic And Nanofluidic Devices, Mark Noble Hamblin Aug 2010

Thin Film Microfluidic And Nanofluidic Devices, Mark Noble Hamblin

Theses and Dissertations

Lab-on-a-chip devices, also known as micro total analysis systems (μTAS), are implementations of chemical analysis systems on microchips. These systems can be fabricated using standard thin film processing techniques. Microfluidic and nanofluidic channels are fabricated in this work through sacrificial etching. Microchannels are fabricated utilizing cores made from AZ3330 and SU8 photoresist. Multi-channel electroosmotic (EO) pumps are evaluated and the accompanying channel zeta potentials are calculated. Capillary flow is studied as an effective filling mechanism for nanochannels. Experimental departure from the Washburn model is considered, where capillary flow rates lie within 10% to 70% of theoretical values. Nanochannels are fabricated …


Arterial Waveform Measurement Using A Piezoelectric Sensor, Ruizhi Zhang Aug 2010

Arterial Waveform Measurement Using A Piezoelectric Sensor, Ruizhi Zhang

Theses and Dissertations

This study aims to develop a new method to monitor peripheral arterial pulse using a PVDF piezoelectric sensor. After comparing different locations of sensor placement, a specific sensor wrap for the finger was developed. Its composition, size, and location make it inexpensive and very convenient to use. In order to monitor the effectiveness of the sensor at producing a reliable pulse waveform, a monitoring system, including the PZT sensor, ECG, pulse-oximeter, respiratory sensor, and accelerometer was setup. Signal analysis from the system helped discover that the PZT waveform is relative to the 1st derivative of the artery pressure wave. Also, …


Growth And Characterization Of Non-Polar Gan Materials And Investigation Of Efficiency Droop In Ingan Light Emitting Diodes, Xianfeng Ni Aug 2010

Growth And Characterization Of Non-Polar Gan Materials And Investigation Of Efficiency Droop In Ingan Light Emitting Diodes, Xianfeng Ni

Theses and Dissertations

General lighting with InGaN light emitting diodes (LEDs) as light sources is of particular interest in terms of energy savings and related environmental benefits due to high lighting efficiency, long lifetime, and Hg-free nature. Incandescent and fluorescent light sources are used for general lighting almost everywhere. But their lighting efficiency is very limited: only 20-30 lm/W for incandescent lighting bulb, approximately 100 lm/W for fluorescent lighting. State-of-the-art InGaN LEDs with a luminous efficacy of over 200 lm/W at room temperature have been reported. However, the goal of replacing the incandescent and fluorescent lights with InGaN LEDs is still elusive since …


An Adaptive Grid-Based All Hexahedral Meshing Algorithm Based On 2-Refinement, Jared D. Edgel Aug 2010

An Adaptive Grid-Based All Hexahedral Meshing Algorithm Based On 2-Refinement, Jared D. Edgel

Theses and Dissertations

Adaptive all-hexahedral meshing algorithms have many desirable features. These algorithms provide a mesh that is efficient for analysis by providing a high element density in specific locations, such as areas of high stress gradient or high curvature and reduced mesh density in other areas of less importance. In addition, inside-out hexahedral grid based schemes, using Cartesian structured grids for the base mesh, have shown great promise in accommodating automatic all-hexahedral algorithms. In these algorithms mesh refinement is generally used to capture geometric features. Unfortunately, most adaptive mesh generation algorithms employ a 3-refinement method. This method, although easy to employ, provides …


Polyurethane-Based Polymer Surface Modifiers With Alkyl Ammonium Co-Polyoxetane Soft Blocks: Reaction Engineering, Surface Morphology And Antimicrobial Behavior, Kennard Brunson Aug 2010

Polyurethane-Based Polymer Surface Modifiers With Alkyl Ammonium Co-Polyoxetane Soft Blocks: Reaction Engineering, Surface Morphology And Antimicrobial Behavior, Kennard Brunson

Theses and Dissertations

Concentrating quaternary (positive) charge at polymer surfaces is important for applications including layer-by-layer polyelectrolyte deposition and antimicrobial coatings. Prior techniques to introduce quaternary charge to the surface involve grafting of quaternary ammonium moieties to a substrate or using polyurethanes with modified hard segments however there are impracticalities involved with these techniques. In the case of the materials discussed, the quaternary charge is introduced via polyurethane based polymer surface modifiers (PSMs) with quaternized soft segments. The particular advantage to this method is that it utilizes the intrinsic phase separation between the hard and soft segments of polyurethanes. This phase separation results …


Real Time 3-D Tracking Of The High Dose Rate Radiation Source Using A Flat Panel Detector, Aditya Bondal Aug 2010

Real Time 3-D Tracking Of The High Dose Rate Radiation Source Using A Flat Panel Detector, Aditya Bondal

Theses and Dissertations

A number of QA procedures have been developed for Breast Brachytherapy treatments, yet none guarantee accurate dose delivery or allow conformation of the actual source position leading to errors sometimes going unnoticed. The objective of this study is to track the exact path the HDR source would follow in real time. The exit radiation of the HDR source was used to image a well defined matrix of markers. The images were acquired using FPD and were processed to obtain projection coordinates while an x-ray calibration image was processed to obtain marker coordinates. Each marker along with its projection represents a …


System Development And Integration Of An Airborne Laser Communications Payload For Unmanned Aircraft Systems, Mariusz Czarnomski Aug 2010

System Development And Integration Of An Airborne Laser Communications Payload For Unmanned Aircraft Systems, Mariusz Czarnomski

Theses and Dissertations

Free space laser communications provides wide bandwidth and high security capabilities to Unmanned Aircraft Systems (UAS) in order to successfully accomplish Intelligence, Surveillance, Target Acquisition, and Reconnaissance (IST AR) missions. A practical implementation of a laser-based video communications payload flown by a small U AS aircraft is described as a proof-of-concept. The two-axis gimbal pointing control algorithm calculates the line-of-sight vector in real-time by using Differential Global Positioning System (DGPS) and Inertial Measurement Unit (IMU) information gathered from the UAS vehicle's autopilot so that the laser transmitter in the airborne payload can accurately track a ground-based photodiode array receiver with …