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Improvement Of Speech Perception For Hearing-Impaired Listeners, Fang Du Dec 2018

Improvement Of Speech Perception For Hearing-Impaired Listeners, Fang Du

Theses and Dissertations

Hearing impairment is becoming a prevalent health problem affecting 5% of world adult populations. Hearing aids and cochlear implant already play an essential role in helping patients over decades, but there are still several open problems that prevent them from providing the maximum benefits. Financial and discomfort reasons lead to only one of four patients choose to use hearing aids; Cochlear implant users always have trouble in understanding speech in a noisy environment.

In this dissertation, we addressed the hearing aids limitations by proposing a new hearing aid signal processing system named Open-source Self-fitting Hearing Aids System (OS SF hearing …


Boron Nitride Thin-Film Deposited By Rf Magnetron Sputtering, Jesus A. Valladares Gonzalez Dec 2018

Boron Nitride Thin-Film Deposited By Rf Magnetron Sputtering, Jesus A. Valladares Gonzalez

Theses and Dissertations

Cubic Boron Nitride is considered a superhard material, its thermochemical stability makes it suitable for applications with corrosive environments and high temperatures. C-BN is grown by PDV on Si substrates. The plasma is energized via an RF source to sputter the target. The ion species in the plasma can be described by the classic electrodynamic expression . Plasma temperature is given by T = (6.2836*E/8*k). The sputter is given by the ratio of the heat transfer to the enthalpy of formation , of the target. The Hall Measurement is performed as recommended by NIST. The measurement was performed on a …


Probabilistic Reliability Analysis Of The Water-Energy Nexus Using Monte Carlo Simulation, Yunfan Zhang Dec 2018

Probabilistic Reliability Analysis Of The Water-Energy Nexus Using Monte Carlo Simulation, Yunfan Zhang

Theses and Dissertations

Nowadays, with the development of science and technologies, our modern society is more and more dependent on the reliable performance of the critical infrastructures. Both water systems and power systems are national critical infrastructure supporting our daily life and the development of economic growth. These two types of systems are highly interconnected and complex networks, which consist of various system elements. Similarly, the core function of water and power system is to deliver satisfactory quality water and power to consumers, and at the same time it should satisfy all the demands at all load points. The reliable performance of these …


Improving Detection Of Dim Targets: Optimization Of A Moment-Based Detection Algorithm, Shannon R. Young Dec 2018

Improving Detection Of Dim Targets: Optimization Of A Moment-Based Detection Algorithm, Shannon R. Young

Theses and Dissertations

Wide area motion imagery (WAMI) sensor technology is advancing rapidly. Increases in frame rates and detector array sizes have led to a dramatic increase in the volume of data that can be acquired. Without a corresponding increase in analytical manpower, much of these data remain underutilized. This creates a need for fast, automated, and robust methods for detecting dim, moving signals of interest. Current approaches fall into two categories: detect-before-track (DBT) and track-before-detect (TBD) methods. The DBT methods use thresholding to reduce the quantity of data to be processed, making real time implementation practical but at the cost of the …


Planar Linear Ion Traps With Microscale Radii For Portable Mass Spectrometry, Trevor Keith Decker Dec 2018

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 Dec 2018

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 …


Cloud Based Wireless Sensor Monitoring, Pruthvi Devendrakumar Mistry Dec 2018

Cloud Based Wireless Sensor Monitoring, Pruthvi Devendrakumar Mistry

Theses and Dissertations

Internet of Things (IoT) brought a revolutionary change in embedded systems. It offloads the physical work of managing an equipment, appliance or device to a smart and network connected application. IoT makes it possible to monitor and control a huge network of devices remotely. The aim of this project is to develop a complete framework for smart data acquisition from a wireless sensor network to cloud servers. The framework includes configurable, low power, and small size embedded module that is attached to a sensor. The device reads data from the sensor and forwards them to the cloud server using the …


Human-Centered Design Of The Enhanced Pilot Learning Interface For The Aviation Community, De Vere Michael Kiss Dec 2018

Human-Centered Design Of The Enhanced Pilot Learning Interface For The Aviation Community, De Vere Michael Kiss

Theses and Dissertations

he purpose of this research is to introduce a new device to help pilots navigate aircraft manuals. This informational navigational tool is designed to improve learning by reducing the time it takes a pilot candidate to retrieve aircraft system information within an aircraft manual. The device is called the Enhanced Pilot Learning Interface, an Advanced Interactive Media. The research project is based on human-centered design and consists of participatory design, modeling and simulation, human-in-the-loop simulation (HITLS), and expert user experience. Additionally, a traditional research experimentation was conducted to collect supporting statistical data. Preliminary tests of four current professional airline pilots …


An Approach To Improve Single Photon Detectors For Highly Sensitive Applications, Ahmed Chyad Kadhim Dec 2018

An Approach To Improve Single Photon Detectors For Highly Sensitive Applications, Ahmed Chyad Kadhim

Theses and Dissertations

The problem of detecting a single photon is receiving considerable attention with the development of new single photon detectors in biophotonics, stressed free-space optical communication, low probability of intercept (LPI) optical communication, quantum communication, and remote sensing. The theoretical modeling of the waveforms of the single photon detector output produced in particular systems will expedite the search for and analysis of detected signals. Since SNSPDs require cooling to very low temperature, 4K, and PMTs work on the visible wavelength, current photon detection focus on research developing SPADs and using InGaAs/InP materials. However, SPADs can work over the infrared range of …


Phonon Polariton Enhanced Infrared Waveguides, Yuchen Yang Dec 2018

Phonon Polariton Enhanced Infrared Waveguides, Yuchen Yang

Theses and Dissertations

The need for robust, reliable and sensitive terahertz (THz) sources and detectors has motivated the research into waveguiding structures. The increasing adoption of micro- and nanofabricated optical components addresses the critical challenge of guiding light with subwavelength confinement. Surface plasmon polariton (SPP) waveguides are among the most promising candidates for manipulating light on subwavelength scales and harbor many potential applications at visible and nearinfrared (NIR) wavelengths. However, the metal in the waveguide yields very weak or nonexistent response in the mid and long wave infrared range, since metal in this region is very lossy and has large magnitude real and …


Big Data And Sensor Network For Construction Material Testing, Yao Shi Nov 2018

Big Data And Sensor Network For Construction Material Testing, Yao Shi

Theses and Dissertations

Engineers and contractors need to have a precise understanding of the development progress of concrete strength in the natural environment, which helps to save project time and cost. However, current practice of concrete construction depends on published data, charts and curves from laboratory tests. The data would not show frequently changing environmental conditions in the real world, which can affect concrete quality significantly. The objective of this research is to design a reliable and accurate method to validate test data of the strength developments of concrete specimens in early stages. The approach includes the following tasks: (1) arrange sensors to …


Vision-Based Emergency Landing Of Small Unmanned Aircraft Systems, Parker Chase Lusk Nov 2018

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 …


Ku-Band Ag Channel Modeling, Albert Smith Oct 2018

Ku-Band Ag Channel Modeling, Albert Smith

Theses and Dissertations

With the rise in use of Unmanned Aerial Systems (UAS), there is a need for safe and reliable integration into existing infrastructure. A proposed system for beyond line of sight control links for UAS is a Ku-band air-to-satellite communication system. To ensure this proposed system does not interfere with existing terrestrial infrastructure that operates in the Ku band, an examination of the Ku-band air-to-ground channel is required. The focus of this thesis is the modeling of the Ku-band AG channel. Tests consisting of transmitting a single tone continuous wave signal were conducted with a signal generator onboard NASA’s Viking S-3 …


Nanofluidic Applications Of Silica Membranes, John Michael Stout Oct 2018

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. …


Non-Destructive Characterization Of Rotated Uniaxial Anisotropic Materials, Alexander G. Knisely Sep 2018

Non-Destructive Characterization Of Rotated Uniaxial Anisotropic Materials, Alexander G. Knisely

Theses and Dissertations

Electromagnetic material characterization of anisotropic media requires measurement diversity, minimal measurement uncertainty and insight into sample symmetry. Additionally, non-destructive characterization techniques are valued over legacy measurement techniques because a destructive approach requires sample preparation to execute a measurement. A Single Port Waveguide Probe (SPWP) non-destructive material characterization technique is proposed to accommodate measuring a metal backed, known thickness, rotated uniaxial anisotropic material. A rotated uniaxial sample possesses unique transverse constitutive components and a longitudinal constitutive component which is the same as one of the transverse values. The SPWP consists of a rectangular waveguide aperture cut in the center of a …


Two Channel Sdm Communication System Simultaneously Operating At 10gb/S Using C-Band Transceivers, Han Wang Sep 2018

Two Channel Sdm Communication System Simultaneously Operating At 10gb/S Using C-Band Transceivers, Han Wang

Theses and Dissertations

Increasing the bandwidth of optical fiber communications to cope with high-speed network traffic is an important goal for the communications industry. Therefore, optical communication is growing at a very rapid pace, including the multiplexing technology. Spatial domain multiplexing (SDM), also known as Space division multiplexing, is a Multi-Input Multi-Output (MIMO) architecture that can increase the data carrying capacity of optical fibers by multiple folds. SDM allows multiple channels of same wavelength to be transmitted in parallel over standard multi-mode fibers, where each SDM channel follows a different helical trajectory while traversing the length of the fiber that lead to unique …


Resistive Solid State Protective Device, Amin Khanlar Aug 2018

Resistive Solid State Protective Device, Amin Khanlar

Theses and Dissertations

Abstract: This thesis describes and explains different fault to characterize fault specifically for DC distribution systems and DC Microgrids fed by synchronous generators. This will result in a testbed for static and intermittent line-to-line faults, and in future work, various types of ground faults. Automaton allows for repeated testing at various voltage levels and precise control over intermittent fault generation. The fault generator is implemented with an IGBT H-bridge topology. Its physical implementation and benefits are described. Experimental results are shown for static line-to-line fault. This testbed will be used to help develop closed-form expressions. Once fault currents are characterized …


Online Hvac Temperature And Air Quality Control For Cost-Efficient Commercial Buildings Based On Lyapunov Optimization Technique, Atiye Maleksadati Aug 2018

Online Hvac Temperature And Air Quality Control For Cost-Efficient Commercial Buildings Based On Lyapunov Optimization Technique, Atiye Maleksadati

Theses and Dissertations

Commercial buildings consume up to 35.5% of total electricity consumed in the United States. As a subsystem in the smart building management system, Heating, Ventilation, and Air Conditioning (HVAC) systems are responsible for 45% of electricity consumption in commercial buildings. Therefore, energy management of HVAC systems is of interest. The HVAC system brings thermal and air quality comfort to the occupants of the building, designing a controller that maximizes this comfort is the first objective. Inevitably, ideal comfort tracking means more energy consumption and energy cost. Hence, the more advanced objective is balancing the comfort-cost tradeoff.

Since HVAC systems have …


Vertical Electrical Impedance Measurements On Concrete Bridge Decks Using A Large-Area Electrode, Jeffrey David Barton Aug 2018

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 …


Automated Impact Response Sounding For Accelerated Concrete Bridge Deck Inspection, Jacob Lynn Larsen Jul 2018

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 …


Evaluation And Design Improvement Of An Augmentative And Alternative Communication Tool For Children With Autism, Moez Lidinallah Fessi Jul 2018

Evaluation And Design Improvement Of An Augmentative And Alternative Communication Tool For Children With Autism, Moez Lidinallah Fessi

Theses and Dissertations

Autism Spectrum Disorder treatment is a real challenge in our society. In an attempt to manage this, Augmentative and Alternative Communication devices became more and more prevalent in the form of software installed on portable devices such as tablets. These mobile applications help individuals with autism to enhance their communication capabilities. Some of the concerns pertaining to the success these systems are the efficacy and the capability, the ease of use, and the user engagement. The research described in this thesis focuses on the usability of a particular application named Livox. This usability evaluation consisted of a threefold approach: (1) …


Body Armor Shape Sensing With Fiber Optic Sensors, Frederick Alexander Seng Jul 2018

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 …


Adaptive Spaceship Cockpit Architecture, Ondřej Doule Jul 2018

Adaptive Spaceship Cockpit Architecture, Ondřej Doule

Theses and Dissertations

This research project is focused on a system design theory and practice of the most complex environment that a human-system architect can ever encounter. It is the environment of the spaceship cockpit or cabin that is affected by forces of propulsion and gravity accelerations and freefall while the direction and magnitude of gravity change during the flight. Furthermore, the hyperbaric, restrictive environment of Intra Vehicular Activity spacesuit adds another layer of complexity. In off-nominal or emergency situations, these environmental effects combine, which results in specific human-system interaction requirements. Considering human-system integration requirements on safety, comfort and efficiency of communication between …


An Empirical Path Loss Model For Wireless Sensor Network Deployment In A Library Environment, Thomas John Misilo Jul 2018

An Empirical Path Loss Model For Wireless Sensor Network Deployment In A Library Environment, Thomas John Misilo

Theses and Dissertations

Wireless networks are becoming more commonplace which has necessitated the know-how to optimally place the devices. There have been studies using wireless sensor networks inside of libraries and museums. However, extensive research has not been completed on propagation modeling for use in the library environment. The main aim of this research is to provide a propagation path loss model for a typical library environment, while comparing two types of antennas (wire and small dipole antenna). This research develops path loss models for a peer-to-peer 2.4 GHz system, where both the transmitter and the receiver are located at the same elevated …


Mitigating Interference With Knowledge-Aided Subarray Pattern Synthesis And Space Time Adaptive Processing, Yongjun Yoon Jun 2018

Mitigating Interference With Knowledge-Aided Subarray Pattern Synthesis And Space Time Adaptive Processing, Yongjun Yoon

Theses and Dissertations

Phased arrays are essential to airborne ground moving target indication (GMTI), as they measure the spatial angle-of-arrival of the target, clutter, and interference signals. The spatial and Doppler (temporal) frequency is utilized by space-time adaptive processing (STAP) to separate and filter out the interference from the moving target returns. Achieving acceptable airborne GMTI performance often requires fairly large arrays, but the size, weight and power (SWAP) requirements, cost and complexity considerations often result in the use of subarrays. This yields an acceptable balance between cost and performance while lowering the system’s robustness to interference. This thesis proposes the use of …


Adjustment Of Rapidscat Backscatter Measurements For Improved Radar Images, Garrett Scott Mcdonald Jun 2018

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 Jun 2018

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 Jun 2018

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 …


Stealth Transmission In Free Space Optical Communication Systems Using Amplified Spontaneous Emission Noise, Youness Ergaibi May 2018

Stealth Transmission In Free Space Optical Communication Systems Using Amplified Spontaneous Emission Noise, Youness Ergaibi

Theses and Dissertations

One of the challenging real-world problems in the communication network is to secure the communication system that deals with a large data. Perhaps even a more challenging version of this scenario is when the channel that transmits the information is a wireless media. This thesis introduces a steganography technique to secure the physical layer of the communication system. It enhances the benefits by using optical communication rather than radio frequency (RF) communication, especially in terms of transmitting a large scale of data. This thesis demonstrates that we can transmit secure large information in free space (air) using steganography mechanism and …


Perovskite Solar Cells Fabricated Via Scalable Dip Coating Methods, Joseph F. Iannello May 2018

Perovskite Solar Cells Fabricated Via Scalable Dip Coating Methods, Joseph F. Iannello

Theses and Dissertations

Perovskite solar cells present the possibility for less expensive electricity generation, through the use of low cost materials and fabrication methods relative to current silicon-based technology. Many current methods of fabricating thin film perovskite solar cells focus on spin-coating, which inherently lacks scalability due to particle conglomeration, poor uniformity over a larger area, and safety concerns. Dip-coating, an alternative to spin-coating, which is explored here addresses these issues which limit scalability. Each individual layer can be separately synthesized, deposited, and characterized, which leads towards scalability. Choosing only the best results from each independent layer allowed progress to the creation of …