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Articles 31 - 60 of 677
Full-Text Articles in Engineering
Increased Cyclist Safety Using An Embedded System, Matthew Ryan Heydorn
Increased Cyclist Safety Using An Embedded System, Matthew Ryan Heydorn
Theses and Dissertations
In order to reduce bicycle-vehicle collisions, we design and implement a cost effectiveembedded system to warn cyclists of approaching vehicles. The system uses an Odroid C2 singleboard computer (SBC) to do vehicle and lane detection in real time using only vision. The system warns cyclist are warned of approaching cars using both a smartphone app and an LED indicator. Due to the limited performance of the Odroid C2 and other low power and low cost SBCs,we found that existing detection algorithms run either too slowly or do not have sufficient accuracy to be practical. Our solution to these limitations is …
Radio Frequency Interference Cancellation,Appraisal, Detection, And Correction, Michael J. Lambert
Radio Frequency Interference Cancellation,Appraisal, Detection, And Correction, Michael J. Lambert
Theses and Dissertations
Radio Astronomy, the study of distant objects in the radio spectrum, is set at defiance against all other users of the electromagnetic spectrum. Where traditional use would fill the electromagnetic spectrum with as much transmission and information as possible, Radio Astronomy would rather no man-made signals existed. Since that is not possible, they grumble and have to deal with unwanted transmissions impinging upon their instruments. I have demonstrated that subspace projection can remove these unwanted signals from Radio Astronomical data in post processing. I demonstrate it both on simulated data and on data taken from the Very Large Array radio …
Analog Adaptive Calibration For Arbitrary Phased Array Configuration, Mark William Nielson
Analog Adaptive Calibration For Arbitrary Phased Array Configuration, Mark William Nielson
Theses and Dissertations
The development of phased array antenna systems requires considerable resources and time. Due to this constraint, the Naval Air Command (NAVAIR) needs a phased array that can be physically reconfigured to meet the demands of multiple missions without added development time or cost. This work develops and demonstrates a solution to this problem by implementing an adaptive calibration approach to the development of electronically steerable antennas (ESAs). In contrast to previous analog adaptive beamformer systems, this system allows for an arbitrary antenna configuration with a variable number of antenna elements and locations. A simulation model of arbitrary phased array configurations …
Neutron Beam Testing Methodology And Results For A Complex Programmable Multiprocessor Soc, Jordan Daniel Anderson
Neutron Beam Testing Methodology And Results For A Complex Programmable Multiprocessor Soc, Jordan Daniel Anderson
Theses and Dissertations
The Xilinx Multiprocessor System-on-Chip (MPSoC) is a complex device that uses 16nm FinFET technology to combine multiple processors, a large amount of FPGA resources, and many I/O interfaces on a single chip die. These features make the MPSoC a high-performance and architecturally flexible device. The potential computing power makes the MPSoC ideal for many embedded applications including terrestrial and space applications. The MPSoC, however, does not have extensive radiation history as many other devices have. The extent of the effect that ionized particles may have on the MPSoC is not well established. To solve this problem, neutron radiation testing can …
Characterization Of Mechanical Properties Of Thin-Film Li-Ion Batteryelectrodes From Laser Excitation And Measurements Ofzero-Group Velocity Resonances, Jing Yao
Theses and Dissertations
The mechanical properties of thin-film Li-ion battery electrodes are controlled by the micro structure of the constituent materials. In this work, a non-contact and non-destructive measurement of the mechanical properties of electrode films is performed by measurement of zero group velocity (ZGV) resonances. The ZGV Lamb wave modes of a solid bi-layer consisting of a thin metallic layer and a thin compliant coating layer are shown to be dependent on the Young's moduli, thicknesses, densities and Poisson ratios of the layers. Theoretical models are used to quantify the sensitivity of the ZGV resonances to changes in mechanical properties. Experimental ZGV …
The Sap Link: A Controller Architecture For Secure Industrial Control Systems, Matthew Cody Wyman
The Sap Link: A Controller Architecture For Secure Industrial Control Systems, Matthew Cody Wyman
Theses and Dissertations
Industrial Control Systems are essential to modern life. They are utilized in hundreds of processes including power distribution, water treatment, manufacturing, traffic management, and amusement park ride control. These systems are an essential part of modern life and if compromised, could result in significant economic loss, safety impacts, damage to the environment, and even loss of life. Unfortunately, many of these systems are not properly secured from a cyber attack. It is likely that a well-funded and motivated attack from a nation-state will successfully compromise an industrial control system's network. As cyber war becomes more prevalent, it is becoming more …
Planar Linear Ion Traps With Microscale Radii For Portable Mass Spectrometry, Trevor Keith Decker
Planar Linear Ion Traps With Microscale Radii For Portable Mass Spectrometry, Trevor Keith Decker
Theses and Dissertations
Radio frequency (RF) ion traps based on the quadrupole device developed by Paul and Steinwedel utilize a dynamic electric field to spatially confine the trajectory of charged particles and may be employed as mass spectrometers by selectively ejecting trapped molecules based on the mass to charge ratio. Because of the inherent sensitivity and specificity of this process, ion trap mass spectrometers have become a popular scientific instrument. In the past two decades there has been a push to develop portable ion trap mass spectrometers for in situ mass analysis by geometrically scaling traps to smaller sizes. This decreases the power …
Assuring Intellectual Property Through Physical And Functional Comparisons, Adam Kendall Hastings
Assuring Intellectual Property Through Physical And Functional Comparisons, Adam Kendall Hastings
Theses and Dissertations
Hardware trojans pose a serious threat to trusted computing. However, hardware trojan detection methods are both numerous and onerous, making hardware trojan detection a difficult and time-consuming procedure. This thesis introduces the IP Assurance Framework, which drastically improves the time it takes design teams to test for hardware trojans. The IP Assurance Framework is implemented in two ways: The first method, Physical Assurance, compares instantiated IP blocks to a golden model via physical-level comparisons, while the second method, Functional Assurance, compares IP to a golden model using logical-level comparisons. Both methods are demonstrated to distinguish between tampered and untampered IP …
Vision-Based Emergency Landing Of Small Unmanned Aircraft Systems, Parker Chase Lusk
Vision-Based Emergency Landing Of Small Unmanned Aircraft Systems, Parker Chase Lusk
Theses and Dissertations
Emergency landing is a critical safety mechanism for aerial vehicles. Commercial aircraft have triply-redundant systems that greatly increase the probability that the pilot will be able to land the aircraft at a designated airfield in the event of an emergency. In general aviation, the chances of always reaching a designated airfield are lower, but the successful pilot might use landmarks and other visual information to safely land in unprepared locations. For small unmanned aircraft systems (sUAS), triply- or even doubly-redundant systems are unlikely due to size, weight, and power constraints. Additionally, there is a growing demand for beyond visual line …
Nanofluidic Applications Of Silica Membranes, John Michael Stout
Nanofluidic Applications Of Silica Membranes, John Michael Stout
Theses and Dissertations
This work presents membrane development applicable in nanofluidic devices. These membranes can also be termed suspended thin films, supported on two or more edges. I first discuss motivation and background for developing these structures. Then I derive the formative principles for nanofluidic systems. Following the derivation of the Navier-Stokes and Washburn equations, I discuss applying these theories to planar nanofluidic capillaries and finish the derivation by discussing the forces that drive liquid flow in nanochannels. I next discuss the membrane development process, starting with my work in static height traps, and develop the concept of analyzing nanoparticles using suspended membranes. …
Intensive Mentoring And Micro-Electronics Research For Students In Engineering (Immerse) 2016 Mentoring Environment Grant, Aaron Hawkins
Intensive Mentoring And Micro-Electronics Research For Students In Engineering (Immerse) 2016 Mentoring Environment Grant, Aaron Hawkins
Journal of Undergraduate Research
The MEG funds used for this projects supported undergraduate students working in the IMMERSE program starting in the Summer of 2016. IMMERSE employed a total of 49 students. Portions of the hourly wages charged by these students for their research work came from this MEG grant.
An Ultra-Low Power Analog-To-Digital Converter For Neural Signal Recording: Comparator Research, Alexander Petrie, Dr. Shiuh-Hua Wood Chiang
An Ultra-Low Power Analog-To-Digital Converter For Neural Signal Recording: Comparator Research, Alexander Petrie, Dr. Shiuh-Hua Wood Chiang
Journal of Undergraduate Research
Brain diseases, such as depression and strokes, affect an ever-increasing number of the human population. Much scientific research has been devoted to finding ways towards alleviating the negative symptoms of these diseases. However, much more research must be conducted before these maladies are no longer a problem. Neural implantable devices are an essential part of such research. These tiny, electronic devices monitor electrical brain activity and wirelessly transmit the collected data to computers so scientists can analyze it. A common issue with these neural recording devices is battery life. Current technology allows for a battery to last only 3-5 years. …
Vertical Electrical Impedance Measurements On Concrete Bridge Decks Using A Large-Area Electrode, Jeffrey David Barton
Vertical Electrical Impedance Measurements On Concrete Bridge Decks Using A Large-Area Electrode, Jeffrey David Barton
Theses and Dissertations
In regions where chloride-based deicing salts are applied to bridge decks, corrosion of the interior steel reinforcement is a major problem. Vertical electrical impedance (VEI) is an effective measurement technique to quantitatively assess the cover protection on bridges against aggressive chemical penetration of reinforced concrete. In its current form, traditional vertical electrical impedance is time-consuming and destructive because a direct connection to the reinforcing steel is required to provide a ground reference. A new method using a large-area electrode (LAE) permits VEI measurement without a direct electrical connection to the steel reinforcement. The LAE creates a nondestructive, semi-direct, low impedance …
Relative Navigation: A Keyframe-Based Approach For Observable Gps-Degraded Navigation, David O. Wheeler, Daniel P. Koch, James S. Jackson, Timothy W. Mclain, Randal W. Beard
Relative Navigation: A Keyframe-Based Approach For Observable Gps-Degraded Navigation, David O. Wheeler, Daniel P. Koch, James S. Jackson, Timothy W. Mclain, Randal W. Beard
Faculty Publications
State estimation for micro air vehicles (MAVs) often depends heavily on reliable global measurements such as GPS. When global measurements are unavailable, additional sensors, such as cameras or laser scanners, are commonly used to provide measurements of the MAV’s translation and rotation relative to a previously observed keyframe image or scan. With the use of only relative sensors, however, the global position and heading of the vehicle are unobservable and cannot be reliably reconstructed. Many existing approaches work with respect to a global reference frame, resulting in a loss of state observability. This article highlights that unobservability leads to inconsistency …
Automated Impact Response Sounding For Accelerated Concrete Bridge Deck Inspection, Jacob Lynn Larsen
Automated Impact Response Sounding For Accelerated Concrete Bridge Deck Inspection, Jacob Lynn Larsen
Theses and Dissertations
Infrastructure deterioration is an international problem requiring significant attention. One particular manifestation of this deterioration is the occurrence of sub-surface cracking (delaminations) in reinforced concrete bridge decks. Of many techniques available for inspection, air-coupled impact-echo testing, or sounding, is a non-destructive evaluation technique to determine the presence and location of delaminations based upon the acoustic response of a bridge deck when struck by an impactor. In this work, two automated air-coupled impact echo sounding devices were designed and constructed. Each device included fast and repeatable impactors, moving platforms for traveling across a bridge deck, microphones for air-coupled sensing, distance measurement …
Body Armor Shape Sensing With Fiber Optic Sensors, Frederick Alexander Seng
Body Armor Shape Sensing With Fiber Optic Sensors, Frederick Alexander Seng
Theses and Dissertations
In this dissertation, the rate of the BFD during body armor impact is characterized with fiber Bragg gratings for the first time ever. The depth rate is characterized using a single fiber optic sensor, while the entire shape rate can be characterized using multiple fiber optic sensors. This is done with a final depth accuracy of less than 10% and a timing accuracy of 15% for BFDs as deep as 50 mm and impact event of less than 1 millisecond. The shape sensing method introduced in this dissertation is different from traditional fiber optic sensor shape reconstruction methods in the …
Adjustment Of Rapidscat Backscatter Measurements For Improved Radar Images, Garrett Scott Mcdonald
Adjustment Of Rapidscat Backscatter Measurements For Improved Radar Images, Garrett Scott Mcdonald
Theses and Dissertations
RapidScat is a spaceborne wind scatterometer mounted on the International Space Station (ISS). The RapidScat mission lasted from September 2014 to November 2016. RapidScat enables the measurement of diurnal patterns of sigma-0 measurements. This capability is possible because of the non-sun-synchronous orbit of the ISS, in which the local time of day (LTOD) of sigma-0 measurements gradually shifts over time in any given location. The ISS platform is a relatively unstable platform for wind scatterometers. Because of the varying attitude of the ISS, RapidScat experiences a constant variation of its pointing vector. Variations of the pointing vector cause variations in …
Using Quantitative Mri To Measure Cartilage Health, Laurel Jane Hales
Using Quantitative Mri To Measure Cartilage Health, Laurel Jane Hales
Theses and Dissertations
Osteoarthritis (OA) is one of the leading causes of disability world-wide. It affects 12% of all Americans ages 25-74 [1]. One of the challenges with OA, is that there are currently no clinically viable methods to measure the health of the cartilage before cartilage loss. There are no ways to replace or heal the cartilage after it has been lost. It is known that the early stages of OA involve a decrease in the amount of glycosaminoglycans (GAG), one of the main molecules in cartilage. This decrease in GAG leads to a change in the fixed charge density of the …
High Throughput Fpga Configuration Using A Custom Dma Configuration Controller, Peter William Zabriskie
High Throughput Fpga Configuration Using A Custom Dma Configuration Controller, Peter William Zabriskie
Theses and Dissertations
SRAM-based Field Programmable Gate Arrays (FPGAs) must be programmed with configuration data every time they are powered on. In addition to initially programming an FPGA, there are many other applications that require access to FPGA configuration memory such as partial reconfiguration, fault injection, and memory scrubbing. This thesis describes a system that provides high-speed, programmable configuration management for Xilinx FPGAs through external interfaces. This system is an improvement upon the JTAG Configuration Manager (JCM) previously created at BYU. The JCM consists of a custom I/O board paired with a MicroZed development board which includes a Xilinx ZYNQ SoC. This platform …
Design Of A Low-Cost Capillary Electrophoresis Laser-Induced Fluorescence System: Lessons Learned When Trying To Build The Lowest Possible Cost System, Steven James Perry
Design Of A Low-Cost Capillary Electrophoresis Laser-Induced Fluorescence System: Lessons Learned When Trying To Build The Lowest Possible Cost System, Steven James Perry
Theses and Dissertations
Capillary electrophoresis laser-induced fluorescence (CE-LIF) is widely used to detect both the presence and concentration of fluorescently labeled biomolecules. In CE-LIF, a plug of sample fluid is electrophoretically driven down a microchannel using a high voltage applied between the opposite ends of the microchannel. Molecules of different sizes and charge states travel at different velocities down the channel. Laser light with a wavelength in the excitation band of the fluorophores is focused near the end of the channel. As each species of molecule passes through the laser spot, the fluorophores emit a fluorescence signal which is measured with an optical …
Design Of A Low-Cost Capillary Electrophoresis Laser-Induced Fluorescence System: Lessons Learned When Trying To Build The Lowest Possible Cost System, Steven James Perry
Design Of A Low-Cost Capillary Electrophoresis Laser-Induced Fluorescence System: Lessons Learned When Trying To Build The Lowest Possible Cost System, Steven James Perry
Theses and Dissertations
Capillary electrophoresis laser-induced fluorescence (CE-LIF) is widely used to detect both the presence and concentration of fluorescently labeled biomolecules. In CE-LIF, a plug of sample fluid is electrophoretically driven down a microchannel using a high voltage applied between the opposite ends of the microchannel. Molecules of different sizes and charge states travel at different velocities down the channel. Laser light with a wavelength in the excitation band of the fluorophores is focused near the end of the channel. As each species of molecule passes through the laser spot, the fluorophores emit a fluorescence signal which is measured with an optical …
Impact Of Antenna Mutual Coupling, Propagation, And Nonreciprocity On Propagation-Based Key Establishment, Attiya Mahmood
Impact Of Antenna Mutual Coupling, Propagation, And Nonreciprocity On Propagation-Based Key Establishment, Attiya Mahmood
Theses and Dissertations
Propagation-based key establishment is a physical layer method for generating encryption keys based on two radios observing a reciprocal propagation channel. This work explores the impact of mutual coupling when communicating nodes are equipped with multiple antennas, multipath richness in the propagation environment, and practical limitations caused by the nonreciprocal nature of RF circuits on key establishment. First, network theory is used to formulate a model of a realistic communication system which incorporates transmit sources and receive loads, impedance matching networks, low-noise amplifiers (LNAs), mutually coupled antenna arrays, and a passive eavesdropper. Afterwards, a detailed analysis is performed to quantify …
Applying Attribute-Based Encryption In Two-Way Radio Talk Groups: A Feasibility Study, Michael Andreas Gough
Applying Attribute-Based Encryption In Two-Way Radio Talk Groups: A Feasibility Study, Michael Andreas Gough
Theses and Dissertations
In two-way radio systems, talk groups are used to organize communication. Some situations may call for creating a temporary talk group, but there are no straightforward ways to do this. Making a new talk group requires programming radios off-line. Temporary groups can be created, but this requires inputting radio IDs which is tedious on a radio's limited controls. By describing group members using attributes, ciphertext-policy attribute-based encryption (CP-ABE) can be used to quickly create sub-groups of a talk group. This scheme requires fewer button presses and messages sent in the new talk group are kept secret. CP-ABE can be used …
The Estimation Of The Rapidscat Spatial Response Function, Samuel Gary Bury
The Estimation Of The Rapidscat Spatial Response Function, Samuel Gary Bury
Theses and Dissertations
RapidScat is a pencil-beam wind scatterometer which operated from September 2014 to August 2016. Mounted aboard the International Space Station (ISS), RapidScat experiences significant altitude and attitude variations over its dataset. These variations need to be properly accounted for to ensure accurate calibration and to produce high resolution scatterometer images. Both the antenna pose and the one-way antenna pattern need to be validated. The spatial response function (SRF) is the two-way antenna pattern for a scatterometer combined with the processing and filtering done in the radar system electronics, and is dominated by the two-way pattern. To verify the pointing of …
Efficient Fpga Soc Processing Design For A Small Uav Radar, Luke Oliver Newmeyer
Efficient Fpga Soc Processing Design For A Small Uav Radar, Luke Oliver Newmeyer
Theses and Dissertations
Modern radar technology relies heavily on digital signal processing. As radar technology pushes the boundaries of miniaturization, computational systems must be developed to support the processing demand. One particular application for small radar technology is in modern drone systems. Many drone applications are currently inhibited by safety concerns of autonomous vehicles navigating shared airspace. Research in radar based Detect and Avoid (DAA) attempts to address these concerns by using radar to detect nearby aircraft and choosing an alternative flight path. Implementation of radar on small Unmanned Air Vehicles (UAV), however, requires a lightweight and power efficient design. Likewise, the radar …
Optimization Methods For A Reconfigurable Ota Chamber, Matthew David Arnold
Optimization Methods For A Reconfigurable Ota Chamber, Matthew David Arnold
Theses and Dissertations
Multiple-input multiple-output (MIMO) technology has enabled increased performance of wireless communication devices. The increased complexity associated with MIMO devices requires more realistic testing environments to ensure device performance. This testing can be accomplished by either very accurate but expensive anechoic chambers, less accurate but inexpensive mode-stirred chambers, or the newly introduced reconfigurable over-the-air chamber (ROTAC) that combines the benefits of both anechoic chambers and reverberation chambers. This work focuses on efficient optimization methods to quantify the performance of the ROTAC. First, an efficient optimization technique that combines convex optimization and a simple gradient descent algorithm is developed that can be …
Multiplexed Optofluidics For Single-Molecule Analysis, Matthew Alan Stott
Multiplexed Optofluidics For Single-Molecule Analysis, Matthew Alan Stott
Theses and Dissertations
The rapid development of optofluidics, the combination of microfluidics and integrated optics, since its formal conception in the early 2000's has aided in the advance of single-molecule analysis. The optofluidic platform discussed in this dissertation is called the liquid core anti-resonant reflecting optical waveguide (LC-ARROW). This platform uses ARROW waveguides to orthogonally intersect a liquid core waveguide with solid core rib waveguides for the excitation of specifically labeled molecules and collection of fluorescence signal. Since conception, the LC-ARROW platform has demonstrated its effectiveness as a lab-on-a-chip fluorescence biosensor. However, until the addition of optical multiplexing excitation waveguides, the platform lacked …
Compiler-Assisted Software Fault Tolerance For Microcontrollers, Matthew Kendall Bohman
Compiler-Assisted Software Fault Tolerance For Microcontrollers, Matthew Kendall Bohman
Theses and Dissertations
Commercial off-the-shelf (COTS) microcontrollers can be useful for non-critical processing on spaceborne platforms. Many of these microprocessors are inexpensive and consume little power. However, the software running on these processors is vulnerable to radiation upsets, which can cause unpredictable program execution or corrupt data. Space missions cannot allow these errors to interrupt functionality or destroy gathered data. As a result, several techniques have been developed to reduce the effect of these upsets. Some proposed techniques involve altering the processor hardware, which is impossible for a COTS device. Alternately, the software running on the microcontroller can be modified to detect or …
Nonlinear Control Framework For Gimbal And Multirotor In Target Tracking, Jae Hun Lee
Nonlinear Control Framework For Gimbal And Multirotor In Target Tracking, Jae Hun Lee
Theses and Dissertations
This thesis presents some existing gimbal and UAV control algorithms as well as novel algorithms developed as the extensions of the existing ones. The existing image-based visual servoing algorithms for both gimbal and UAV require the depth information to the object of interest. The depth information is not measurable when only a monocular camera is used for tracking. This thesis is the result of contemplation to the question: how can the necessity for a depth measurement be removed? A novel gimbal algorithm using adaptive control is developed and presented with simulation and hardware results. Although the estimated depth using the …
Waveguide-Based Spatial Light Modulators For Use In Holographic Video Displays, Kamran Qaderi
Waveguide-Based Spatial Light Modulators For Use In Holographic Video Displays, Kamran Qaderi
Theses and Dissertations
Film display holograms typically diffract light over a wide enough view-angle to be viewed, directly, without intervening optics. However, all holographic video displays must use optics beyond the hologram surface to overcome the challenges of small display extent and low diffraction angle by using some form of demagnification and derotation. We report a leaky mode waveguide spatial light modulator (SLM) with sufficiently high angular diffraction to obviate the need for demagnification in scanned aperture systems. This was achieved by performing a number of experiments to determine the depth of the annealed, proton-exchanged waveguide which corresponded to a maximized diffracted angle. …