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Full-Text Articles in Engineering

Single Photon Avalanche Diode (Spad) Array Quenching And A Novel Quantum Random Number Generator (Qrng), Mano Rahul Kumar Pakalapati Dec 2019

Single Photon Avalanche Diode (Spad) Array Quenching And A Novel Quantum Random Number Generator (Qrng), Mano Rahul Kumar Pakalapati

Theses and Dissertations

Single Photon Avalanche Diodes, SPADs is a single-photon sensitive light detector with capabilities of pico-second timing resolutions and offer potential for enhancing various fields of science to evolve into quantum-age. SPAD has applications ranging from quantum computing, cryptography (QKD) to applications in medicine such as neural imaging and Single Photon Emission Computed Tomography (SPECT). SPAD arrays are gaining popularity as they enable for parallel photon detection and 3D imaging. To account for the process tolerances and aging, each SPAD-pixel needs a tunable quenching circuit in the frontend for post-fabrication fine-tuning, this research work presents a novel Dual Triggered Tunable Active …


Assessment Of Sensory Abnormalities In Children With Asd Using Virtual Reality, Ankit Koirala Dec 2019

Assessment Of Sensory Abnormalities In Children With Asd Using Virtual Reality, Ankit Koirala

Theses and Dissertations

Sensory abnormality is one of the important characteristics of Autism Spectrum Disorder(ASD). A large number of studies suggest a strong connection between sensory abnormalities and ASD. Therefore, it is important to assess sensory abnormalities for diagnosis and intervention of ASD. In this thesis study, we aim to develop a virtual reality system that can measure sensory abnormalities in adolescents with ASD. Sensory abnormalities can affect all five senses: touch, vision, smell, taste and auditory. However, in this study, we focus on assessing sensory abnormality in vision and touch sensory processing. Twelve adolescents with ASD and 12 typically developing (TD) adolescents …


Dual-Task Multimodal Web Browsing In Semi-Autonomous Vehicles, Jarrett William Clark Dec 2019

Dual-Task Multimodal Web Browsing In Semi-Autonomous Vehicles, Jarrett William Clark

Theses and Dissertations

Drivers should remain alert when operating semi-autonomous vehicles as human intervention is required when the automated systems fail, or an unusual situation is encountered. However, drivers do not always focus solely on the road and sometimes divert their attention to look at cell phones, laptops, tablet computers, or in-dash infotainment systems. In this research, software was created to enable operators of a simulated self-driving car to browse the Human-Centered Design Institute (HCDI) website using multimodal interaction. The software used synthesized speech to read the website aloud and visually highlighted the content on the screen as it was read. Web analytics …


Vehicle Interior Access Deployable Worksurface Mechanism Concept Product Design, Premchand Gunachandran Dec 2019

Vehicle Interior Access Deployable Worksurface Mechanism Concept Product Design, Premchand Gunachandran

Theses and Dissertations

by

Premchand Gunachandran

The University of Wisconsin-Milwaukee, 2019

Under the Supervision of Professor Mohammad Habibur Rahman

Easy access and adjusting the vehicle interior configuration to a variety of situations and uses is the general desire for any vehicle user. To meet such desire an attempt has been made in this study to conceptualize a design to develop a new mechatronic product called re-configurable vehicle interior console mechanism to deploy a worksurface (DWS), which will provide flexible use of the vehicle’s interior of both partial and fully autonomous vehicles. This re-configurable vehicle interior console will deploy the DWS using a power …


Scatter Reduction By Exploiting Behaviour Of Convolutional Neural Networks In Frequency Domain, Carlos Ivan Jerez Gonzalez Dec 2019

Scatter Reduction By Exploiting Behaviour Of Convolutional Neural Networks In Frequency Domain, Carlos Ivan Jerez Gonzalez

Theses and Dissertations

In X-ray imaging, scattered radiation can produce a number of artifacts that greatly

undermine the image quality. There are hardware solutions, such as anti-scatter grids.

However, they are costly. A software-based solution is a better option because it is

cheaper and can achieve a higher scatter reduction. Most of the current software-based

approaches are model-based. The main issues with them are the lack of flexibility, expressivity, and the requirement of a model. In consideration of this, we decided to apply

Convolutional Neural Networks (CNNs), since they do not have any of the previously

mentioned issues.

In our approach we split …


Mathematical Model, Simulated Design And Experimental Results For Parabolic Mirror Based Multiplexer For Spatially Multiplexed Fiber Optic Communication Systems, Ce Su Dec 2019

Mathematical Model, Simulated Design And Experimental Results For Parabolic Mirror Based Multiplexer For Spatially Multiplexed Fiber Optic Communication Systems, Ce Su

Theses and Dissertations

Spatial Domain Multiplexing (SDM) is a multi-input multi-output (MIMO) architecture. It adds an innovative dimension to optical fiber communication systems by enabling spatial reuse of the optical frequencies. SDM utilizes radially distributed spatial locations for different input signals based on their input launch angles. These input channels propagate in a helical path inside the carrier fiber. These SDM input channels do not encounter any perceptible cross-talk or inter-symbol interference. The SDM system is similar to other optical communication systems. However, they require two added parts. These parts are the spatial multiplexer, also known as the Beam Combiner Module (BCM) and …


Mdt Geolocation Through Machine Learning: Evaluation Of Supervised Regression Ml Algorithms, Aria Canadell Solana Dec 2019

Mdt Geolocation Through Machine Learning: Evaluation Of Supervised Regression Ml Algorithms, Aria Canadell Solana

Theses and Dissertations

Minimizing Drive Test is a statistical protocol used to evaluate the network performance. It provides several benefits with respect to traditional drive test analysis; however, multiple inconveniences exist that prevent cell companies from precisely retrieving most of the locations of these reports. . MATLAB and Jupyter Notebook were used to prepare the data and create the models. Multiple supervised regression algorithms were tested and evaluated. The best predictions were obtained from the K-Nearest Neighbor algorithm with one ‘k’ and distance-weighted predictions. The UE geolocation was predicted with a median accuracy of 5.42 meters, a mean error of 61.62 meters, and …


Performance Evaluation Of Speech Recognition System Using Conventional And Hybrid Features And Hidden Markov Model Classifier, Hussien Elharati Dec 2019

Performance Evaluation Of Speech Recognition System Using Conventional And Hybrid Features And Hidden Markov Model Classifier, Hussien Elharati

Theses and Dissertations

Extracting the auditory information from speech signal is considered a computationally demanding task. However, past researches in mathematics, acoustics, and speech technology have provided many methods for signal processing and modeling. Although, all methods have their strengths and weaknesses, but they remain a serious attempt towards speech recognition system. Using multivariate statistical machine learning (Hidden Markov Model), this work investigates the performance of selected conventional and new hybrid feature extraction algorithms in both clean and noisy environments. The resultant conventional features include MFCC, LPCC, PLP, and RASTA-PLP, while the new hybrid features include LPR, MLP, MLR, and MPR. The whole …


Optimization Of Cabin Design For Enhanced Passenger Experience, Golnoosh Torkashvand Dec 2019

Optimization Of Cabin Design For Enhanced Passenger Experience, Golnoosh Torkashvand

Theses and Dissertations

Passenger experience has been a recent focus of many airline industries. Airline manufacturers and businesses have noticed that in order to stay sustainable in the competition of the market, they need to understand passengers’ needs. Passenger experience, however, is a broad concept that requires more effort to understand. This research is an attempt towards understanding passenger experience and suggesting a framework toward enhancing it in long-haul flights. We consider an activity-centric approach toward redefining passenger experience and evaluating it. In addition, we employ Human-Centered Design (HCD) methodologies to grasp a better understanding of passengers’ perceptions of those activities. HCD is …


Monitoring And Correlating Toxic Gases Emitted By Cars In Public Indoor Garage In Real-Time Using Internet Of Things (Iot), Khalid Altheiab Dec 2019

Monitoring And Correlating Toxic Gases Emitted By Cars In Public Indoor Garage In Real-Time Using Internet Of Things (Iot), Khalid Altheiab

Theses and Dissertations

The study was developed to adequately depict the behavior of indoor pollutant matter in public garages, the underlying factors influencing this behavior and gauge the pollutant exhaust emission patterns. In depicting the behavior of indoor pollutant matter, the research aimed at studying the emission-pollutant relationship and any variations in concentrations found at different locations within the study site. In terms of measuring the factors influencing the pollutant behavior, the research quantified the concentrations of four gaseous contaminants. The pollutant behavior was studied to better understand the different variables influencing the indoor air-quality. Finally, based on these parameters overall patterns in …


Air Quality Monitoring Wireless Sensor Network With Electrochemical Sensing Elements, Saeed Faisal Malky Dec 2019

Air Quality Monitoring Wireless Sensor Network With Electrochemical Sensing Elements, Saeed Faisal Malky

Theses and Dissertations

Harmful atmospheric pollutants have been attributed to causing adverse weather conditions and health problems, which are particularly prevalent in more populated global regions, such as megacities. Nongovernmental and international agencies throughout the world have likewise called for increased awareness and action to effectively counter the increased rates of air pollution, as the consequences seem ominous. Meanwhile, in several major urban landscapes such as Saudi Arabia, no modern apparatus or efficient systematic mechanisms exist for the qualitative detection of dangerous pollutants and gases. The current counterparts for hazardous gas measurements are expensive, bulky and cumbersome to set up. Thus, sensor devices …


Cavity Environmental Control System Upgrade For Nasa’S Stratospheric Observatory For Infrared Astronomy, Ashraf Al-Hajjeh Dec 2019

Cavity Environmental Control System Upgrade For Nasa’S Stratospheric Observatory For Infrared Astronomy, Ashraf Al-Hajjeh

Theses and Dissertations

The main goal of this project is to fulfill the need of a controller upgrade for the Cavity Environmental Control System (CECS) on NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) aircraft. The preceding controller had multiple disadvantages including operating in an unpressurized region, incomplete functionality implementation, limited fault and status monitoring capability, and reduced maintainability and reliability. The new controller will go through the NASA design process to fulfill all the requirements of CECS operation including complete functionality of all devices currently installed on the aircraft, added devices to improve fault and health monitoring, and overall improvement in maintainability and …


Exploring Methods For Studying Recoverability Of Shipboard Electrical Power Distribution Systems, Jacob David Gudex Dec 2019

Exploring Methods For Studying Recoverability Of Shipboard Electrical Power Distribution Systems, Jacob David Gudex

Theses and Dissertations

Advancement of the technology included on ships, is changing the nature of loads installed on ships. Not only are there more loads than installed power generation, but advanced electrically powered weapons and sensors are changing the profile of the installed loads. These are challenges for future shipboard power systems design. Challenges which must be solved with careful distribution system planning, energy storage integration, and selection of individual power electronic converters within the ship. Different topologies and distribution systems have differing fault isolation and recovery (FIR) capability sets, which affects ship survivability. Furthermore, different FIR capability sets, operate at different speeds. …


The Challenges Of Low-Energy Secondary Electron Emission Measurement, Matthew J. Vincie Nov 2019

The Challenges Of Low-Energy Secondary Electron Emission Measurement, Matthew J. Vincie

Theses and Dissertations

The phenomena known as secondary electron emission was discovered over a century ago. Yet it remains very difficult to model accurately due to the limited availability of reliable experimental data. With the growing use of computer simulations in hardware development, the need for accurate models has increased. This research focused on determining what factors may be causing measurement discrepancies and methods for increasing the accuracy of measurements. It was found that several assumptions are commonly invoked when these measurements are performed that may not always be consistent with reality. The violation of these assumptions leads to measurement bias that is …


Mobile Ad Hoc Networks In Transportation Data Collection And Dissemination, Kardigue Konte Oct 2019

Mobile Ad Hoc Networks In Transportation Data Collection And Dissemination, Kardigue Konte

Theses and Dissertations

The field of transportation is rapidly changing with new opportunities for systems solutions and emerging technologies. The global economic impact of congestion and accidents are significant. Improved means are needed to solve them. Combined with the increasing numbers of vehicles on the road, the net economic impact is measured in the many billions of dollars. Promising methodologies explored in this thesis include the use of the Internet of Things (IoT) and Mobile Ad Hoc Networks (MANET). Interconnecting vehicles using Dedicated Short Range Communication technology (DSRC) brings many benefits. Integrating DSRC into roadway vehicles offers the promise of reducing the problems …


Tissue-Specific Roles Of Transforming Growth Factor Beta Ligands In Cardiac Outflow Tract Malformations And Calcific Aortic Valve Disease, Nadia Al-Sammarraie Oct 2019

Tissue-Specific Roles Of Transforming Growth Factor Beta Ligands In Cardiac Outflow Tract Malformations And Calcific Aortic Valve Disease, Nadia Al-Sammarraie

Theses and Dissertations

Congenital heart defects and adult calcific aortic valve disease are two of the leading causes of morbidity and mortality worldwide. To date, there is no medical cure and surgical intervention is the main option of treatment. The cardiac outflow tract is the major site for these abnormalities, which are triggered by genetic and/or environmental factors that alter development and/or homeostasis. Recently, significant roles of TGFβ signaling in development of cardiovascular disorders have become more evident in humans, however, the specific requirement of individual TGFβ ligands on the pathogenesis of OFT malformations and diseases remains elusive. In the present work, three …


Wireless Rf Induced Energy Absorption And Heating Of Lanthanum-Nickel Alloy In The Near-Field, Michael Dillon Lindsay Oct 2019

Wireless Rf Induced Energy Absorption And Heating Of Lanthanum-Nickel Alloy In The Near-Field, Michael Dillon Lindsay

Theses and Dissertations

This thesis will investigate whether and how a synthetic metal-magnetic alloy absorbs enough near-field electromagnetic (EM) radiation for heating. Although resistive elements could be used for indirect heating, a wireless radio frequency (RF) method is explored because of its advantages in its non-intrusive nature and its ability to direct or focus energy within a specific area. For our case, the RF heating process relies on the materials ability to absorb sufficient RF energy due to the induced currents. We expect there to be significant surface resistance due to the conductivity and magnetic permeability of the material and thus heat. This …


Adaptive-Hybrid Redundancy For Radiation Hardening, Nicolas S. Hamilton Sep 2019

Adaptive-Hybrid Redundancy For Radiation Hardening, Nicolas S. Hamilton

Theses and Dissertations

An Adaptive-Hybrid Redundancy (AHR) mitigation strategy is proposed to mitigate the effects of Single Event Upset (SEU) and Single Event Transient (SET) radiation effects. AHR is adaptive because it switches between Triple Modular Redundancy (TMR) and Temporal Software Redundancy (TSR). AHR is hybrid because it uses hardware and software redundancy. AHR is demonstrated to run faster than TSR and use less energy than TMR. Furthermore, AHR allows space vehicle designers, mission planners, and operators the flexibility to determine how much time is spent in TMR and TSR. TMR mode provides faster processing at the expense of greater energy usage. TSR …


Target Detection In Heterogeneous Clutter With Low Resolution Radar, Kyle G. Stankowski Sep 2019

Target Detection In Heterogeneous Clutter With Low Resolution Radar, Kyle G. Stankowski

Theses and Dissertations

This thesis develops a framework for SAR target detection and super-resolution in low-resolution environments. The primary focus in this research is the background clutter heterogeneity that often accompanies low range and cross-range resolutions. A corrective model which accounts for clutter replacement is developed to define the detection and false alarm rates of the detector more accurately than a traditional model in which the radar return from the target supplements the existing clutter. In a heterogeneous clutter cell, the clutter replacement model leverages the different scattering distributions among the individual clutter types to generate a probability distribution function for the areas …


Advanced Metering Infrastructure Security With Software-Defined Network In Smart Grid, Yi-Chen Chung Sep 2019

Advanced Metering Infrastructure Security With Software-Defined Network In Smart Grid, Yi-Chen Chung

Theses and Dissertations

The Advanced Metering Infrastructure (AMI) is the most important and basic element in the Smart Grid systems. Technologies grow complicated as the world becomes more convenient. Power grid, smart building, electric vehicles, and other technology need to be managed and maintained flawlessly in case of the possibility of cyberattacks to shut down all the systems and result in huge loss economically or potentially affect people's life. It is important to use communication technologies to provide many functions including facilitate bidirectional communications and remote controls. Since AMI needs to be widely deployed to each home user, power companies are required to …


Nondestructive Electromagnetic Characterization Of Perfect-Electric-Conductor-Backed Uniaxial Materials, Adam L. Brooks Sep 2019

Nondestructive Electromagnetic Characterization Of Perfect-Electric-Conductor-Backed Uniaxial Materials, Adam L. Brooks

Theses and Dissertations

As the use of anisotropic materials in electromagnetic applications continues to proliferate, it becomes increasingly important to develop non-destructive evaluation methods for those materials in their installed configuration. In many applications, these materials are permanently affixed onto conducting bodies to reduce unwanted reflections, making it impossible to collect S21 or S12 transmission measurements as used in many techniques based on the well-known Nicolson-Ross-Weir algorithm. It also makes it impractical to reorient the sample to collect orthogonal measurements aligned with the optical axes of the anisotropic material. The goal of this research is to develop a two-reflection coefficient measurement …


Digital Holography Efficiency Experiments For Tactical Applications, Douglas E. Thornton Sep 2019

Digital Holography Efficiency Experiments For Tactical Applications, Douglas E. Thornton

Theses and Dissertations

Digital holography (DH) uses coherent detection and offers direct access to the complex-optical field to sense and correct image aberrations in low signal-to-noise environments, which is critical for tactical applications. The performance of DH is compared to a similar, well studied deep-turbulence wavefront sensor, the self-referencing interferometer (SRI), with known efficiency losses. Wave optics simulations with deep-turbulence conditions and noise were conducted and the results show that DH outperforms the SRI by 10's of dB due to DH's strong reference. Additionally, efficiency experiments were conducted to investigate DH system losses. The experimental results show that the mixing efficiency (37%) is …


Autonomous And Resilient Management Of All-Source Sensors For Navigation Assurance, Juan D. Jurado Sep 2019

Autonomous And Resilient Management Of All-Source Sensors For Navigation Assurance, Juan D. Jurado

Theses and Dissertations

All-source navigation has become increasingly relevant over the past decade with the development of viable alternative sensor technologies. However, as the number and type of sensors informing a system increases, so does the probability of corrupting the system with sensor modeling errors, signal interference, and undetected faults. Though the latter of these has been extensively researched, the majority of existing approaches have constrained faults to biases, and designed algorithms centered around the assumption of simultaneously redundant, synchronous sensors with valid measurement models, none of which are guaranteed for all-source systems. This research aims to provide all-source multi-sensor resiliency, assurance, and …


A Comparison Of Lithium-Ion Cathode Vertical Homogeneity As Influenced By Drying Rate And Drying Method, Alexander Jay Smart Sep 2019

A Comparison Of Lithium-Ion Cathode Vertical Homogeneity As Influenced By Drying Rate And Drying Method, Alexander Jay Smart

Theses and Dissertations

During lithium-ion battery electrode fabrication, slurry drying conditions influence the resulting microstructure of electrodes. It has been found that the drying conditions can result in non-uniform cathode microstructures and material distributions. Accelerated drying, for example, is widely assumed to cause the binder in an electrode to migrate within the slurry, which can contribute to adhesion failure, and ultimately capacity fade and reduced battery life. While there are some conflicting studies regarding the aspects of accelerated drying that cause binder migration, there is not a widely used standard metric for measuring the gradient of binder across the thickness of an electrode. …


Targeted Germanium Ion Irradiation Of Aluminum Gallium Nitride/Gallium Nitride High Electron Mobility Transistors, Melanie E. Mace Aug 2019

Targeted Germanium Ion Irradiation Of Aluminum Gallium Nitride/Gallium Nitride High Electron Mobility Transistors, Melanie E. Mace

Theses and Dissertations

Microscale beams of germanium ions were used to target different locations of aluminum galliumnitride/gallium nitride (AlGaN/GaN) high electron mobility transistors (HEMTs) to determine location dependent radiation effects. 1.7 MeV Ge ions were targeted at the gap between the gate and the drain to observe displacement damage effects while 47 MeV Ge ions were targeted at the gate to observe ionization damage effects. Electrical data was taken pre, during, and post irradiation. To separate transient from permanent degradation, the devices were characterized after a room temperature anneal for at least 30 days. Optical images were also analyzed pre and post irradiation. …


Light Scattering In Diffraction Limit Infrared Imaging, Ghazal Azarfar Aug 2019

Light Scattering In Diffraction Limit Infrared Imaging, Ghazal Azarfar

Theses and Dissertations

Fourier Transform Infrared (FTIR) microspectroscopy is a noninvasive technique for chemical imaging of micrometer size samples. Employing an infrared microscope, an infrared source and FTIR spectrometer coupled to a microscope with an array of detectors (128 x 128 detectors), enables collecting combined spectral and spatial information simultaneously. Wavelength dependent images are collected, that reveal biochemical signatures of disease pathology and cell cycle. Single cell biochemistry can be evaluated with this technique, since the wavelength of light is comparable to the size of the objects of interest, which leads to additional spectral and spatial effects disturb biological signatures and can confound …


Sensing With Geometry-Dependent Magnetostriction Via An Embedded Fiber Bragg Grating, David Frailey Aug 2019

Sensing With Geometry-Dependent Magnetostriction Via An Embedded Fiber Bragg Grating, David Frailey

Theses and Dissertations

Fiber optic current sensors (FOCSs) have unique advantages in electromagnetic interference

immunity and direct current measurements. Here, magnetostrictive composites and

their interactions with embedded ber Bragg gratings (FBG) were explored to form novel

FOCSs with predictable and temperature-independent sensitivity. Magnetostrictive, particularly

Terfenol-D/epoxy, composites maintain the mangetostrictive expansion under an

external magnetic eld while gaining

exibility in engineering. In contrast to ordinary strain

gauges, an embedded FBG can provide an optical signal inferring simultaneously a strain

and its gradient inside a composite. In principle, the sensing of strain gradient is thermally

independent. Creating appropriate geometries for magnetostrictive composites enables the

conversion …


Multi-Tap Extended Kalman Filter For A Periodic Waveform With Uncertain Frequency And Waveform Shape, And Data Dropouts, Justin Saboury Aug 2019

Multi-Tap Extended Kalman Filter For A Periodic Waveform With Uncertain Frequency And Waveform Shape, And Data Dropouts, Justin Saboury

Theses and Dissertations

Gait analysis presents the challenge of detecting a periodic waveform in the presence of time varying frequency, amplitude, DC offset, and waveform shape, with acquisition gaps from partial occlusions. The combination of all of these components presents a formidable challenge. The Extended Kalman Filter for this system model has six states, which makes it weakly identifiable within the standard Extended Kalman Filter network. In this work, a novel robust Extended Kalman Filter-based approach is presented and evaluated for clinical use in gait analysis. The novel aspect of the proposed method is that at each sample, the present and several past …


A Fault-Tolerant Control Strategy For Three-Level Neutral-Point Clamped (Npc) Inverter, Weijun Zhu Aug 2019

A Fault-Tolerant Control Strategy For Three-Level Neutral-Point Clamped (Npc) Inverter, Weijun Zhu

Theses and Dissertations

When the open-circuit fault occurs on neutral-point clamped (NPC) inverters, it can cause the distortion of output currents, excessively large fluctuation of output voltages, and unbalanced neutral-point potential. Currently, several existing fault diagnosis methods are able to identify the fault types, but they are unable to identify the switching devices where the open-circuit faults occur. Furthermore, even if the open-circuit faults can be identified, the implications caused by open-circuit faults need to be further addressed. This thesis is focused on diagnosing the open-circuit faults and mitigating the problems caused by these faults.

An effective fault diagnosis method is proposed in …


Improving The Single Event Effect Response Of Triple Modular Redundancy On Sram Fpgas Through Placement And Routing, Matthew Joel Cannon Aug 2019

Improving The Single Event Effect Response Of Triple Modular Redundancy On Sram Fpgas Through Placement And Routing, Matthew Joel Cannon

Theses and Dissertations

Triple modular redundancy (TMR) with repair is commonly used to improve the reliability of systems. TMR is often employed for circuits implemented on field programmable gate arrays (FPGAs) to mitigate the radiation effects of single event upsets (SEUs). This has proven to be an effective technique by improving a circuit's sensitive cross-section by up to 100x. However, testing has shown that the improvement offered by TMR is limited by upsets in single configuration bits that cause TMR to fail.This work proposes a variety of mitigation techniques that improve the effectiveness of TMR on FPGAs. These mitigation techniques can alter the …