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Exploitation Of Unintentional Information Leakage From Integrated Circuits, William E. Cobb
Exploitation Of Unintentional Information Leakage From Integrated Circuits, William E. Cobb
Theses and Dissertations
Unintentional electromagnetic emissions are used to recognize or verify the identity of a unique integrated circuit (IC) based on fabrication process-induced variations in a manner analogous to biometric human identification. The effectiveness of the technique is demonstrated through an extensive empirical study, with results presented indicating correct device identification success rates of greater than 99:5%, and average verification equal error rates (EERs) of less than 0:05% for 40 near-identical devices. The proposed approach is suitable for security applications involving commodity commercial ICs, with substantial cost and scalability advantages over existing approaches. A systematic leakage mapping methodology is also proposed to …
Link Performance Analysis For A Proposed Future Architecture Of The Air Force Satellite Control Network, Eric W. Nelson
Link Performance Analysis For A Proposed Future Architecture Of The Air Force Satellite Control Network, Eric W. Nelson
Theses and Dissertations
The Air Force Satellite Control Network (AFSCN) is a worldwide network of ground stations that support a wide variety of users from the National Aeronautics and Space Administration (NASA) to the National Reconnaissance Office (NRO). The network performs tracking, telemetry, and commanding (TT&C) for these varied users. Users, located at Satellite Operations Centers (SOC), must compete for time on the AFSCN. This thesis demonstrates how to predict satellite link performance, specifically by users of the AFSCN. It will also demonstrate how users might use this capability to save spacecraft power. A tool was created called the AFSCN Link Predictor (LP) …
Rapid Development: A Content Analysis Comparison Of Literature And Purposive Sampling Of Afrl Rapid Reaction Projects, Andrew R. Smith
Rapid Development: A Content Analysis Comparison Of Literature And Purposive Sampling Of Afrl Rapid Reaction Projects, Andrew R. Smith
Theses and Dissertations
In the current environment of military operations requesting faster delivery schedules to counter insurgent tactics, the engineering team often searches for how to quickly deliver the 80% solution, typically in 6-12 months. These are labeled rapid development projects. A content analysis of best practices in commercial product development literature, where time to market is often a driving factor, was accomplished showing varying emphasis of systems engineering technical and technical management processes. Technical Planning, Stakeholders Requirements Development, and Architecture Design were identified as important processes. This analysis confirms preconceived notions of plan upfront and early by emphasizing the SE processes of …
Electroluminescence Studies On Longwavelength Indium Arsenide Quantum Dot Microcavities Grown On Gallium Arsenide, John C. Ramsey
Electroluminescence Studies On Longwavelength Indium Arsenide Quantum Dot Microcavities Grown On Gallium Arsenide, John C. Ramsey
Theses and Dissertations
A comprehensive study of the electroluminescence of four GaAs/AlGaAs microcavity devices with InAs/GaInAs quantum dot active regions emitting near 1.3 µm was conducted. The four molecular beam epitaxial grown samples with AlAs oxide aperture confinement layers were fabricated, characterized, and optically modeled. Optical power transmission of the samples was modeled using Matlab and compared with measured transmission data. Resonant cavity light emitting diodes (RCLEDs) and three vertical cavity surface emitting laser (VCSEL) samples were fabricated and electro-optically characterized over a range of injection currents and temperatures. Devices achieved continuous wave room temperature lasing at 1.28 µm with an output power …
Linear-Quadratic Control Of A Mems Micromirror Using Kalman Filtering, Jamie P. Schnapp
Linear-Quadratic Control Of A Mems Micromirror Using Kalman Filtering, Jamie P. Schnapp
Theses and Dissertations
The deflection limitations of electrostatic flexure-beam actuators are well known. Specifically, as the beam is actuated and the gap traversed, the restoring force necessary for equilibrium increases proportionally with the displacement to first order, while the electrostatic actuating force increases with the inverse square of the gap. Equilibrium, and thus stable open-loop voltage control, ceases at one-third the total gap distance, leading to actuator snap-in. A Kalman Filter is designed with an appropriately complex state dynamics model to accurately estimate actuator deflection given voltage input and capacitance measurements, which are then used by a Linear Quadratic controller to generate a …
A Method For Measuring Programmatic Dependency And Interdependency Between Dod Acquisition Programs, Matthew B. Christensen
A Method For Measuring Programmatic Dependency And Interdependency Between Dod Acquisition Programs, Matthew B. Christensen
Theses and Dissertations
There is currently no accepted method for quantitative measurement of acquisition program interdependency. While some methods exist for measuring dependency or interdependency at the component or system level, these methods do not translate well to program interdependency measurement. The objective of this thesis is to provide a model for measuring acquisition program interdependency accurately and quantitatively. The model presented in this thesis uses four Interdependency Factors to identify dependency relationships between programs. Specific Interdependency Levels are then used to measure the strengths of those dependencies. The model also accounts for measurement of dependencies upon programs that are not directly connected, …
Investigation Of Gallium Nitride Transistor Reliability Through Accelerated Life Testing And Modeling, Bradley D. Christiansen
Investigation Of Gallium Nitride Transistor Reliability Through Accelerated Life Testing And Modeling, Bradley D. Christiansen
Theses and Dissertations
Gallium nitride high electron mobility transistors are attractive to the DoD for their ability to operate at high frequencies, voltages, temperatures, and power. Yet, there are concerns about the reliability of these devices. Various degradation mechanisms and their causes are proposed in the literature. A variety of reliability tests were conducted to understand these mechanisms and causes. A multi-stressor experiment revealed different failure mechanisms than are in the literature. In particular, the devices tested at high voltage in the OFF state did not degrade significantly as suggested by others' reports. The validity of temperature-accelerated life testing when applied to GaN …
Development Of Photographic Dynamic Measurements Applicable To Evaluation Of Flapping Wing Micro Air Vehicles, Jeremy C. Murray
Development Of Photographic Dynamic Measurements Applicable To Evaluation Of Flapping Wing Micro Air Vehicles, Jeremy C. Murray
Theses and Dissertations
Developments in the area of flapping wing micro air vehicles (FWMAVs) of a small size and with limited range. This has lead to a great deal of interest in biomimetric designs based on flapping wing flyers, including the North American Hawkmoth (Manduca Sexta). By utilizing high speed photography and photogrammetry the dynamic flapping of the wing can be characterized for comparison with mathematical models, namely computational fluid dynamics (CFD) and finite element analysis (FEA).To successfully utilize high speed image capture, a method of successfully digitizing many data points in a short period of time needs to be developed. The effort …
A Comparative Evaluation Of An Educational Program Designed To Enable Mechanical Engineering Students To Develop Global Competence, Aaron Gerald Ball
A Comparative Evaluation Of An Educational Program Designed To Enable Mechanical Engineering Students To Develop Global Competence, Aaron Gerald Ball
Theses and Dissertations
The 'flattening of the world', using Thomas Friedman's phraseology, is driving corporations to increasingly use collaborative engineering processes and global teams to operate on a global scale. Globalization of the traditional university engineering curriculum is necessary to help students prepare to work in a global environment. More scalable and economically sustainable program types are needed to enable the majority of students to obtain a globalized education. The purpose of this research was to determine how effectively a global team- and project-based computer aided engineering course provided learning opportunities that enabled students to develop elements of global competence in comparison to …
The Use Of Various Failure Criteria As Applied To High Speed Wear, David A. Huber
The Use Of Various Failure Criteria As Applied To High Speed Wear, David A. Huber
Theses and Dissertations
This research has been aimed at developing methods to predict mechanical wear of sliding bodies at high velocities. Specifically, wear of test sled slippers at the Holloman High Speed Test Track at Holloman AFB, NM, is being considered. Developing a numerical model to represent the velocity range achieved at the test track is infeasible, so numerical modeling techniques must be adopted. Previous research has made use of finite element codes to simulate the high velocity sliding event. However, the extreme velocities at the test track can create numerical errors in the finite element codes. To avoid the numerical errors, an …
Scramjet Isolator Modeling And Control, John R. Hutzel
Scramjet Isolator Modeling And Control, John R. Hutzel
Theses and Dissertations
The scramjet isolator is a duct in which pressure increases from the inlet to the combustor via a shock train. The shock train leading edge (LE) location must be controlled in an operational scramjet. A LE location measurement algorithm, dynamic model, and control algorithm were developed and validated with 500 frame per second (FPS) shadowgraph images in this research. The test apparatus consisted of a direct connect cold-flow high-speed wind tunnel with an adjustable ramp mounted in the tunnel floor. Ramp adjustments changed the tunnel cross-sectional area which changed the tunnel back pressure and LE location. Wall-mounted pressure transducers and …
Coupled Radiation-Gasdynamic Solution Method For Hypersonic Shock Layers In Thermochemical Nonequilibrium, Christopher L. Martin Jr.
Coupled Radiation-Gasdynamic Solution Method For Hypersonic Shock Layers In Thermochemical Nonequilibrium, Christopher L. Martin Jr.
Theses and Dissertations
The purpose of this research was to develop a highly accurate computational method for calculating the nonequilibrium radiative heat transfer within reentry shock layers. The nonequilibrium state of the flowfield was solved using the multispecies multitemperature nonequilibrium flow solver NH7AIR which is capable of separately tracking the vibrational energy of each diatomic species and the energy of the free electrons. The calculation of radiative heat transfer was performed by utilizing the detailed line-by-line spectral radiation solver SPRADIAN. Two radiative transport schemes were implemented in this coupled code. The first scheme was the standard tangent slab solution method. The second scheme …
Chemical Templating By Afm Tip-Directed Nano-Electrochemical Patterning, Kyle A. Nelson
Chemical Templating By Afm Tip-Directed Nano-Electrochemical Patterning, Kyle A. Nelson
Theses and Dissertations
This work has examines the creation and use of chemical templates for nanocircuit and other nanodevice fabrication. Chemical templating can be useful in attachment, orientation and wiring of molecularly templated circuits. DNA origami provides a suitable method for creating molecularly templated circuits as DNA can be folded into complex shapes and functionalized with active circuit elements, such as semiconducting nanomaterials. Surface attachment of DNA origami structures can be accomplished by hybridization of dangling single-stranded DNA (ssDNA) on the origami structures with complementary surface-bound strands. Chemical templating provides a pathway for placing the patterned surface-bound attachment points needed for surface alignment …
Safety Issues Among Hispanic Construction Workers Along The Wasatch Front In Utah, Phavel Israel Loayza Chahuayo
Safety Issues Among Hispanic Construction Workers Along The Wasatch Front In Utah, Phavel Israel Loayza Chahuayo
Theses and Dissertations
During the last few decades immigration by foreigners seeking work in the construction industry in the United States has increased dramatically. Of those seeking jobs in construction, Hispanics represent the largest and fastest growing population. The proportion of reportable accidents among Hispanic on-site construction workers in the United States is higher than that of non-Hispanics. This trend of on-site construction accidents is evident not only in states that have traditionally high populations of Hispanics, such as New York, Florida, California, Arizona, and Texas, it is also manifested in the State of Utah. This research focused on causes of accidents among …
Modeling Solid Propellant Ignition Events, Daniel A. Smyth
Modeling Solid Propellant Ignition Events, Daniel A. Smyth
Theses and Dissertations
This dissertation documents the building of computational propellant/ingredient models toward predicting AP/HTPB/Al cookoff events. Two computer codes were used to complete this work; a steady-state code and a transient ignition code Numerous levels of verification resulted in a robust set of codes to which several propellant/ingredient models were applied. To validate the final cookoff predictions, several levels of validation were completed, including the comparison of model predictions to experimental data for: AP steady-state combustion, fine-AP/HTPB steady-state combustion, AP laser ignition, fine-AP/HTPB laser ignition, AP/HTPB/Al ignition, and AP/HTPB/Al cookoff. A previous AP steady-state model was updated, and then a new AP …
Detail Extraction From Electron Backscatter Diffraction Patterns, John A. Basinger
Detail Extraction From Electron Backscatter Diffraction Patterns, John A. Basinger
Theses and Dissertations
Cross-correlation based analysis of electron backscatter diffraction (EBSD) patterns and the use of simulated reference patterns has opened up entirely new avenues of insight into local lattice properties within EBSD scans. The benefits of accessing new levels of orientation resolution and multiple types of previously inaccessible data measures are accompanied with new challenges in characterizing microscope geometry and other error previously ignored in EBSD systems. The foremost of these challenges, when using simulated patterns in high resolution EBSD (HR-EBSD), is the determination of pattern center (the location on the sample from which the EBSD pattern originated) with sufficient accuracy to …
A Performance-Based Model For The Computation Of Kinematic Pile Response Due To Lateral Spreading And Its Application On Select Bridges Damaged During The M7.6 Earthquake In The Limon Province, Costa Rica, Kevin W. Franke
Theses and Dissertations
Lateral spread is a seismic hazard associated with soil liquefaction in which permanent deformations are developed within the soil profile due to cyclic mobility. Lateral spread has historically been one of the largest causes of earthquake-related damage to infrastructure. One of the infrastructure components most at risk from lateral spread is that of deep foundations. Because performance-based engineering is increasingly becoming adopted in earthquake engineering practice, it would be beneficial for engineers and researchers to have a performance-based methodology for computing pile performance during a lateral spread event. This study utilizes the probabilistic performance-based framework developed by the Pacific Earthquake …
Creativity And Innovation: A Comparative Analysis Of Assessment Measures For The Domains Of Technology, Engineering, And Business, Tyler Lewis
Theses and Dissertations
The purpose of this literature review is to investigate and discuss: (1) the characteristics measured by innovation assessments, and (2) the comparison of characteristics measured by creativity assessments with those of innovation assessments. This will be done by: (1) collecting creativity and innovation assessments, and (2) comparing and contrasting the characteristics measured by each assessment. This study reveals that innovation assessments do not measure the innovation process in its entirety. The findings show that creativity and innovation assessments lack in assessing the entire innovation process, assessing the innovation process on an individual level, and assessing an individual's change or growth …
Model Decomposition And Constraints To Parametrically Partition Design Space In A Collaborative Cax Environment, Felicia Diane Marshall
Model Decomposition And Constraints To Parametrically Partition Design Space In A Collaborative Cax Environment, Felicia Diane Marshall
Theses and Dissertations
An industry survey was conducted to collect information on current collaboration methods and project management and communication structures. The results, along with other design collaboration philosophies, were used to develop a method of coordinating users in a multi-user design space. These thesis methods will regulate collaboration and avoid user collisions in the same model space, either by cooperative interaction or by spatial decomposition with regional blocking. The method partitions the design space by integrating a graphical user interface tool into the engineering application used to define and assign the necessary tasks of the project. A simple implementation of this method …
Damage Tolerance Of Unidirectional Basalt/Epoxy Composites In Co-Cured Aramid Sleeves, Devin Nelson Allen
Damage Tolerance Of Unidirectional Basalt/Epoxy Composites In Co-Cured Aramid Sleeves, Devin Nelson Allen
Theses and Dissertations
Unidirectional basalt fiber rods consolidated with an aramid sleeve were measured for compression strength after impact at various energy levels and compared to undamaged control specimens. These structural elements represent local members of open three-dimensional composite lattice structures (e.g., based on isogrid or IsoTruss® technologies) that are continuously fabricated using advanced three-dimensional braiding techniques. The unidirectional core specimens, nominally 8 mm (5/16") and 11 mm (7/16") in diameter, were manufactured using bi-directional braided sleeves or unidirectional spiral sleeves with full or partial (approximately half) coverage of the core fibers. The 51 mm (2") specimens were shorter than the critical buckling …
Damage Tolerance Of Buckling-Critical Unidirectional Carbon, Glass,And Basalt Fiber Composites In Co-Cured Aramid Sleeves, Michael D. Embley
Damage Tolerance Of Buckling-Critical Unidirectional Carbon, Glass,And Basalt Fiber Composites In Co-Cured Aramid Sleeves, Michael D. Embley
Theses and Dissertations
Compression strength after impact tests were conducted on unidirectional composite rods with sleeves. These elements represent local members of open three-dimensional composite lattice structures (e.g., based on isogrid or IsoTruss® technologies). The unidirectional cores composed of carbon, glass, or basalt fiber/epoxy composites were co-cured in aramid sleeves. Sleeve patterns included both bi-directional (unsymmetric) braids and unidirectional spiral wraps with sleeve coverage ranging from nominally half to full. The diameters were nominally 8 and 11 mm (5/16 and 7/16 in). The larger diameter had nominally twice the cross-sectional area, to quantify the effects of scaling. The specimens were long enough to …
A Framework For Studying The Physical Degradation Characteristics Of Dvds And Their Relationship To Digital Errors, Brian K. Saville
A Framework For Studying The Physical Degradation Characteristics Of Dvds And Their Relationship To Digital Errors, Brian K. Saville
Theses and Dissertations
The methods used to store data on DVD-R discs have been proven to work over the last 15 years. However, there has been a growing concern that these discs will be outlasted by the paper records they were meant to replace. The data on a DVD-R is stored as optical contrasts which have the potential to be misread and even damaged. This damage may occur either on the surface or internally to the disc, especially on the recording layer itself. The literature is saturated with studies attempting to determine the time period in which discs may fail and what the …
Reduction In Wick Drain Effectiveness In Typical Utah Clays, Gabriel M. Smith
Reduction In Wick Drain Effectiveness In Typical Utah Clays, Gabriel M. Smith
Theses and Dissertations
Consolidation theory states that decreasing the spacing of prefabricated vertical drains will decrease the time required to achieve primary consolidation. Previous field tests have shown that there exists a "critical" drain spacing, which is the point at which further spacing decrease does not decrease the time of primary consolidation. This "critical" spacing is thought to be due to disturbance effects from installation of the drains. Previous studies have found that the "critical" drain spacing may be dependent upon soil layering and drain and mandrel dimensions. Thin, interbedded clay layers have been found to be affected greatly due to the smear …
Strength Of Concrete Masonry Prisms Constructed With Non-Traditional Grout And Type-M Mortar, Scott Michael Watterson
Strength Of Concrete Masonry Prisms Constructed With Non-Traditional Grout And Type-M Mortar, Scott Michael Watterson
Theses and Dissertations
The Concrete Masonry Association of California and Nevada in conjunction with Brigham Young University devised a masonry prism testing scheme to aid in the determination of whether prisms constructed with grouts possessing high levels of supplemental cementitious materials could meet minimum masonry compressive strength requirements. ASTM standards, identical to that of concrete, place restrictions on quantities, by weight, of supplemental materials that can replace ordinary Portland cement. For an all fly ash replacement, up to 40% of Portland cement can be replaced while up to 70% can be replaced by a fly ash-slag combination. Research is focused on class F …
Development Of A Grond-Based High-Resolution 3d-Sar System For Studying The Microwave Scattering Characteristics Of Trees, Justin Frank Penner
Development Of A Grond-Based High-Resolution 3d-Sar System For Studying The Microwave Scattering Characteristics Of Trees, Justin Frank Penner
Theses and Dissertations
This thesis presents the development of a high-resolution ground-based 3D-SAR system and investigates its application to microwave-vegetation studies. The development process of the system is detailed including an enumeration of high-level requirements, discussions on key design issues, and detailed descriptions of the system down to a component level. The system operates on a 5.4 GHz (C-band) signal, provides a synthetic aperture area of 1.7 m x 1.7 m, and offers resolution of 0.75 m x 0.3 m x 0.3 m (range x azimuth x elevation). The system is employed on several trees with varying physical characteristics. The resulting imagery demonstrates …
Avian Hazard Advisory System (Ahas): An Evaluation Of Ahas Accuracy As A Predictive Tool In Bird Strike Risk Assessment For Civil Aviation, Inger Catherine Oyoko
Avian Hazard Advisory System (Ahas): An Evaluation Of Ahas Accuracy As A Predictive Tool In Bird Strike Risk Assessment For Civil Aviation, Inger Catherine Oyoko
Theses and Dissertations
The problem of bird strikes began when human aviators made their first ventures in flight and joined birds in an already crowded environment. In the decades following these first flights, the bird strike problem has resulted in numerous fatalities and millions of dollars worth of damaged or destroyed aircraft in both civil and military aviation. The problem has been further exacerbated by the technological leaps in the aviation industry such as the increase in the number of aircraft and engines on an aircraft, the introduction of the jet engine, and also faster, quieter more efficient engine design making aircraft harder …
Selective Deposition Of Metallic And Semiconductor Materials Onto Dna Templates For Nanofabrication, Jianfei Liu
Selective Deposition Of Metallic And Semiconductor Materials Onto Dna Templates For Nanofabrication, Jianfei Liu
Theses and Dissertations
This work examines the selective deposition of metallic and semiconductor materials onto DNA templates for the fabrication of nanodevices. DNA origami provides a simple and robust method for folding DNA into a variety of shapes and patterns and makes it possible to create the complex templates needed for nanodevices, such as nanoelectronic circuits, plasmonics, and nanosensors. Metallization of DNA origami templates is essential for the fabrication of such nanodevices. In addition, selective deposition of semiconductor materials onto the DNA template is of importance for making many nanodevices such as nanocircuits. Metallization of DNA origami presents several challenges beyond those associated …
Using Commodity Flow Data For Predicting Truck Freight Flow On State Truck Routes, Goangsung Jin
Using Commodity Flow Data For Predicting Truck Freight Flow On State Truck Routes, Goangsung Jin
Theses and Dissertations
The increase in truck traffic on highways has brought many problems and challenges to transportation planning and traffic operation, including traffic congestion, transportation system deficiency (insufficient truck parking, etc.), safety, infrastructure deterioration, environmental impacts (air quality and noise), economic development, and so forth. Along with the increase in truck traffic, the need for developing a statewide truck freight demand model has grown so that a state can estimate truck traffic at any point on its highways. The most significant hurdle to including freight transportation in the transportation modeling process is that most of the demand forecasting methodologies currently available were …
Improved Stereo Vision Methods For Fpga-Based Computing Platforms, Wade S. Fife
Improved Stereo Vision Methods For Fpga-Based Computing Platforms, Wade S. Fife
Theses and Dissertations
Stereo vision is a very useful, yet challenging technology for a wide variety of applications. One of the greatest challenges is meeting the computational demands of stereo vision applications that require real-time performance. The FPGA (Field Programmable Gate Array) is a readily-available technology that allows many stereo vision methods to be implemented while meeting the strict real-time performance requirements of some applications. Some of the best results have been obtained using non-parametric stereo correlation methods, such as the rank and census transform. Yet relatively little work has been done to study these methods or to propose new algorithms based on …
Influence Of Supraglottal Geometry And Modeling Choices On The Flow-Induced Vibration Of A Computational Vocal Fold Model, Timothy E. Shurtz
Influence Of Supraglottal Geometry And Modeling Choices On The Flow-Induced Vibration Of A Computational Vocal Fold Model, Timothy E. Shurtz
Theses and Dissertations
Computational models of the flow-induced vibrations of the vocal folds are powerful tools that can be used in conjunction with physical experiments to better understand voice production. This thesis research has been performed to contribute to the understanding of vocal fold dynamics as well as several aspects of computational modeling of the vocal folds. In particular, the effects of supraglottal geometry have been analyzed using a computational model of the vocal folds and laryngeal airway. In addition, three important computational modeling parameters (contact line location, Poisson's ratio, and symmetry assumptions) have been systematically varied to determine their influence on model …