An Investigation Into Magnetic Gears And Magnetic Springs For Marine Hydrokinetic Power Generators,
2022
Portland State University
An Investigation Into Magnetic Gears And Magnetic Springs For Marine Hydrokinetic Power Generators, Hossein Baninajar
Dissertations and Theses
Marine hydrokinetic generators often use mechanical gears to convert the low-speed motion into the high-speed rotary motion that is required for conventional electrical generators. While mechanical gearboxes have a high torque density and can reach high efficiencies, they suffer from serious reliability issues. Recently, magnetic gearing technology has been proposed as a means of making hydrokinetic generators more reliable. As magnetic gears use magnetic field modulation to create speed change, they offer a high reliability, nonfriction, power transmission mechanism that limits the wear to only the bearings and makes the magnetic gears almost maintenance-free. During an over-torque condition, a magnetic …
Towards Improved Inertial Navigation By Reducing Errors Using Deep Learning Methodology,
2022
University of Dayton
Towards Improved Inertial Navigation By Reducing Errors Using Deep Learning Methodology, Hua Chen, Tarek M. Taha, Vamsy P. Chodavarapu
Electrical and Computer Engineering Faculty Publications
Autonomous vehicles make use of an Inertial Navigation System (INS) as part of vehicular sensor fusion in many situations including GPS-denied environments such as dense urban places, multi-level parking structures, and areas with thick tree-coverage. The INS unit incorporates an Inertial Measurement Unit (IMU) to process the linear acceleration and angular velocity data to obtain orientation, position, and velocity information using mechanization equations. In this work, we describe a novel deep-learning-based methodology, using Convolutional Neural Networks (CNN), to reduce errors from MEMS IMU sensors. We develop a CNN-based approach that can learn from the responses of a particular inertial sensor …
Aerial Radiation Detection Identification And Measurement System Detector Material Comparison Study,
2022
20th CBRNE Command
Aerial Radiation Detection Identification And Measurement System Detector Material Comparison Study, Benjamin C. Troxell, Kacey D. Mcgee, Christina L. Dugan
Faculty Publications
The 20th Chemical Biological Radiological Nuclear and Explosives Command (CBRNE) currently utilizes an airborne sodium iodide gamma and beta detection system to map radiation fields over large areas of interest. The 20th CBRNE explored emergent detector technologies utilizing two detection materials; thallium-activated cesium iodide and high purity germanium (HPGe). These detectors were simulated at various altitudes and compared to background measurements. The sodium iodide detector failed to provide isotopic discrimination at distance. The thallium-activated cesium iodide CsI(Tl) detector provided sufficient absolute efficiency and energy resolution to identify isotopics at distance. The HPGe detector provided the best energy resolution. However, current …
Pseudo-Modal Expansions For Generating Random Electromagnetic Beams,
2022
Air Force Institute of Technology
Pseudo-Modal Expansions For Generating Random Electromagnetic Beams, Milo W. Hyde Iv, Olga Korotkova
Faculty Publications
Excerpt: We derive two pseudo-modal expansions that provide insight into the structure of stationary electromagnetic sources and can be used for their physical realization and in computer simulations. Both expansions are derived from the vectorial version of Bochner’s theorem of functional analysis.
Polarization-Sensitive Optical Responses From Natural Layered Hydrated Sodium Sulfosalt Gerstleyite,
2022
Missouri University of Science and Technology
Polarization-Sensitive Optical Responses From Natural Layered Hydrated Sodium Sulfosalt Gerstleyite, Ravi P. N. Tripathi, Xiaodong Yang, Jie Gao
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Multi-element layered materials have gained substantial attention in the context of achieving the customized light-matter interactions at subwavelength scale via stoichiometric engineering, which is crucial for the realization of miniaturized polarization-sensitive optoelectronic and nanophotonic devices. Herein, naturally occurring hydrated sodium sulfosalt gerstleyite is introduced as one new multi-element van der Waals (vdW) layered material. The mechanically exfoliated thin gerstleyite flakes are demonstrated to exhibit polarization-sensitive anisotropic linear and nonlinear optical responses including angle-resolved Raman scattering, anomalous wavelength-dependent linear dichroism transition, birefringence effect, and polarization-dependent third-harmonic generation (THG). Furthermore, the third-order nonlinear susceptibility of gerstleyite crystal is estimated by the probed …
Malware Detection Using Electromagnetic Side-Channel Analysis,
2022
Air Force Institute of Technology
Malware Detection Using Electromagnetic Side-Channel Analysis, Matthew A. Bergstedt
Theses and Dissertations
Many physical systems control or monitor important applications without the capacity to monitor for malware using on-device resources. Thus, it becomes valuable to explore malware detection methods for these systems utilizing external or off-device resources. This research investigates the viability of employing EM SCA to determine whether a performed operation is normal or malicious. A Raspberry Pi 3 was set up as a simulated motor controller with code paths for a normal or malicious operation. While the normal path only calculated the motor speed before updating the motor, the malicious path added a line of code to modify the calculated …
Magnetic Flux Channel Antenna Design In Conformal Applications,
2022
Air Force Institute of Technology
Magnetic Flux Channel Antenna Design In Conformal Applications, William J. Tremblay
Theses and Dissertations
Magnetic Flux Channels (MFC) and Magneto-Dielectric Wire Antennas (MDWA) are effective, and in some cases, superior alternatives to traditional metallic antennas, in conformal and electrically small applications at the cost of fabrication and feed complexity. The frequency dispersive nature of magnetic material constituent parameters imposes constraints on the antenna design process, which were not fully developed in prior art. This research quantifies the key differences between the operating regions of magneto-dielectric materials for antenna applications and demonstrates the effectiveness of numerical method augmented modal analysis in the design process, regardless of operating region. Modeling challenges associated with MDWAs are addressed …
Magnetic Anomaly Absolute Positioning For Hypersonic Aircraft,
2022
Air Force Institute of Technology
Magnetic Anomaly Absolute Positioning For Hypersonic Aircraft, Alexander J. Mcneil
Theses and Dissertations
GPS has proven to be an extremely valuable asset for navigation, and timing. GPS has become the standard navigation system for all applications, but GPS has limitations. GPS is susceptible to jamming, spoofing, and in the case of hypersonic aircraft, is likely unavailable. When an aircraft is traveling at hypersonic speeds, there is a plasma sheath that surrounds the aircraft. This plasma sheath blocks electromagnetic waves, and is therefore responsible for a GPS blackout. GPS unavailability for hypersonic aircraft has prompted the research into the viability of alternate navigation systems for these aircraft. This paper seeks to explore the viability …
Resolving The Three-Dimensional Rotational And Translational Dynamics Of Single Molecules Using Radially And Azimuthally Polarized Fluorescence,
2022
Washington University in St Louis
Resolving The Three-Dimensional Rotational And Translational Dynamics Of Single Molecules Using Radially And Azimuthally Polarized Fluorescence, Oumeng Zhang, Weiyan Zhou, Jin Lu, Tingting Wu, Matthew D. Lew
Electrical & Systems Engineering Publications and Presentations
We report a radially and azimuthally polarized (raPol) microscope for high detection and estimation performance in single-molecule orientation-localization microscopy (SMOLM). With 5000 photons detected from Nile red (NR) transiently bound within supported lipid bilayers (SLBs), raPol SMOLM achieves 2.9 nm localization precision, 1.5° orientation precision, and 0.17 sr precision in estimating rotational wobble. Within DPPC SLBs, SMOLM imaging reveals the existence of randomly oriented binding pockets that prevent NR from freely exploring all orientations. Treating the SLBs with cholesterol-loaded methyl-β-cyclodextrin (MβCD-chol) causes NR’s orientational diffusion to be dramatically reduced, but curiously NR’s median lateral displacements drastically increase from 20.8 to …
A Deep Neural Network For Early Detection And Prediction Of Chronic Kidney Disease,
2022
University of Petroleum and Energy Studies
A Deep Neural Network For Early Detection And Prediction Of Chronic Kidney Disease, Vijendra Singh, Vijayan K. Asari, Rajkumar Rajasekaran
Electrical and Computer Engineering Faculty Publications
Diabetes and high blood pressure are the primary causes of Chronic Kidney Disease (CKD). Glomerular Filtration Rate (GFR) and kidney damage markers are used by researchers around the world to identify CKD as a condition that leads to reduced renal function over time. A person with CKD has a higher chance of dying young. Doctors face a difficult task in diagnosing the different diseases linked to CKD at an early stage in order to prevent the disease. This research presents a novel deep learning model for the early detection and prediction of CKD. This research objectives to create a deep …
Characteristic Mode Analysis Prediction And Guidance Of Electromagnetic Coupling Measurements To A Uav Model,
2022
Missouri University of Science and Technology
Characteristic Mode Analysis Prediction And Guidance Of Electromagnetic Coupling Measurements To A Uav Model, Mohamed Z. M. Hamdalla, Benjamin Bissen, James D. Hunter, Yuanzhuo Liu, Victor Khilkevich, Daryl G. Beetner, Anthony N. Caruso, Ahmed M. Hassan
Electrical and Computer Engineering Faculty Research & Creative Works
In this work, we study the current coupled to a simplified Unmanned Aerial Vehicle (UAV) model using a dual computational and experimental approach. The simplified surrogate structure reduced the computational burden and facilitated the experimental measurement of the coupled currents. For a practical system, a wide range of simulations and measurements must be performed to analyze the induced current variations with respect to properties of the incident excitation waveform, such as the frequency, angle of incidence, and polarization. To simplify this analysis, Characteristic Mode Analysis (CMA) was used to compute the eigen-currents of the UAV model and predict where and …
Direct Laser Writing Below The Diffraction Limit By Exploring Multi-Pulse-Induced Physics,
2022
University of Central Florida
Direct Laser Writing Below The Diffraction Limit By Exploring Multi-Pulse-Induced Physics, Boyang Zhou
Electronic Theses and Dissertations, 2020-2023
Ultrafast laser ablation has enabled high-precision processing of a wide range of materials including metals, semiconductors, dielectrics, and polymers. Several laser nanostructuring methods exist, including those based on optical near-fields, special material properties, surface plasmons, and multiphoton absorption (MPA). Among these methods, the MPA method has the potential for nanoscale direct laser writing by using a simple experimental setup. However, the understanding of the fundamental mechanism involved in the laser ablation process is still incomplete, and it remains challenging to obtain a feature size much smaller than the diffraction-limited spot size. The goal of this research is to understand how …
4.74 Ghz Harmonically Operated Saw Device For Sensing Applications And Interrogation System,
2022
University of Central Florida
4.74 Ghz Harmonically Operated Saw Device For Sensing Applications And Interrogation System, Michael Morales Otero
Electronic Theses and Dissertations, 2020-2023
Surface acoustic wave (SAW) devices have provided solutions to many sensor applications. With the increasing use of the electromagnetic spectrum, the adoption of higher frequencies for new developments is becoming a necessity. SAW devices represent a solution for advancing many emerging sensor's needs given their inherent advantages such as: wireless operation, low cost, and ease of fabrication. However, the SAW technology has been typically limited to frequencies under 3 GHz due to size limitations, increased SAW losses, and the need of an interrogation system suitable for reading SAW sensors at higher frequencies. This dissertation presents the work done to push …
A Progressive Learning Strategy For Large-Scale Glacier Mapping,
2022
University of Dayton
A Progressive Learning Strategy For Large-Scale Glacier Mapping, Zhiyuan Xie, Umesh K. Haritashya, Vijayan K. Asari
Electrical and Computer Engineering Faculty Publications
In recent years, the worldwide temperature increase has resulted in rapid deglaciation and a higher risk of glacier-related natural hazards such as flooding and debris flow. Due to the severity of these hazards, continuous observation and detailed analysis of glacier fluctuations are crucial. Many such analyses require an accurately delineated glacier boundary. However, the complexity and heterogeneity of glaciers, particularly debris-covered glaciers (DCGs), poses a challenge for glacier mapping when using conventional remote sensing or machine-learning techniques. Some examples exist about small-scale automated glacier mapping, but large or regional-scale mapping is challenging. Previously, a deep-learning-based approach named GlacierNet2 had been …
Volumetric Microfabrication With Structured Light,
2022
University of Central Florida
Volumetric Microfabrication With Structured Light, He Cheng
Electronic Theses and Dissertations, 2020-2023
Multiphoton polymerization (MPP) as one of the direct laser writing techniques is capable of manufacturing three-dimensional (3D) micro-structures with complex shapes and novel functionalities. However, current MPP methods rely on point-by-point or layer-by-layer scanning and therefore are time-consuming. The low fabrication throughput of conventional MPP is the key factor that limits its wider adoption for industrial manufacturing over large surface area. One way to increase the fabrication speed is to turn layer-by-layer process into a volumetric process. An ideal volumetric printing method can fabricate structures with complex 3D geometry by single exposure and should be easy to implement. As a …
Patterned Liquid Crystal Devices For Near-Eye Displays,
2022
University of Central Florida
Patterned Liquid Crystal Devices For Near-Eye Displays, Kun Yin
Electronic Theses and Dissertations, 2020-2023
As a promising next-generation display, augmented reality (AR) and virtual reality (VR) have shown attractive features and attracted broad interests from both academia and industry. Currently, these near-eye displays (NEDs) have enabled numerous applications, ranging from education, medical, entertainment, to engineering, with the help of compact and functional patterned liquid crystal (LC) devices. The interplay between LC patterns and NEDs stimulates the development of novel LC devices with unique surface alignments and volume structures, which in turn feedback to achieve more compact and versatile NEDs. This dissertation will focus on the patterned LC with applications in NEDs. Firstly, we propose …
Light Guiding And Concentrating Using Self-Collimating Spatially-Variant Photonic Crystals,
2022
University of Central Florida
Light Guiding And Concentrating Using Self-Collimating Spatially-Variant Photonic Crystals, Chun Xia
Electronic Theses and Dissertations, 2020-2023
Advances in integrated photonic devices require low loss, easy-to-integrate solutions for chip-to-chip and chip-to-fiber interfacing. Among the most common solutions are traditional lenses. However, circular lenses require additional mounting mechanisms to ensure proper alignment. Additionally, the beam routing functionality cannot be added to the traditional lenses unless they are combined with mirrors and operate in the reflection mode. In this dissertation, we investigate lens-embedded photonic crystals (LEPCs) as a solution to flat and multifunctional lenses. The concept is demonstrated by creating self-collimating lattices containing a gradient refractive index lens (GRIN-LEPC), a binary-shaped lens (B-LEPC), and a Fresnel-type binary-shaped lens (F-B-LEPC). …
Diffractive Liquid Crystal Optical Elements For Near-Eye Displays,
2022
University of Central Florida
Diffractive Liquid Crystal Optical Elements For Near-Eye Displays, Jianghao Xiong
Electronic Theses and Dissertations, 2020-2023
Liquid crystal planar optics (LCPO) with versatile functionalities is emerging as a promising candidate for overcoming various challenges in near-eye displays, like augmented reality (AR) and virtual reality (VR), while maintaining a small form factor. This type of novel optical element exhibits unique properties, such as high efficiency, large angular/spectral bandwidths, polarization selectivity, and dynamic modulation. The basic molecular configuration of these novel reflective LCPO is analyzed, based on the simulation of molecular dynamics. In contrast to previously assumed planar-twist structure, our analysis predicts a slanted helix structure, which agrees with the measured results. The optical simulation model is established …
Development Of Holographic Phase Masks For Wavefront Shaping,
2022
University of Central Florida
Development Of Holographic Phase Masks For Wavefront Shaping, Nafiseh Mohammadian
Electronic Theses and Dissertations, 2020-2023
This dissertation explores a new method for creating holographic phase masks (HPMs), which are phase transforming optical elements holographically recorded in photosensitive glass. This novel hologram recording method allows for the fast production of HPMs of any complexity, as opposed to the traditional multistep process, which includes the design and fabrication of a master phase mask operating in the UV region before the holographic recording step. We holographically recorded transmissive HPMs that are physically robust (they are recorded in a silicate glass volume), can handle tens of kilowatts of continuous wave (CW) laser power, are un-erasable, user defined, require no …
Modeling, Fabrication, And Characterization Of Rf-Based Passive Wireless Sensors Composed Of Refractory Semiconducting Ceramics For High Temperature Applications,
2022
West Virginia University
Modeling, Fabrication, And Characterization Of Rf-Based Passive Wireless Sensors Composed Of Refractory Semiconducting Ceramics For High Temperature Applications, Kavin Sivaneri Varadharajan Idhaiam
Graduate Theses, Dissertations, and Problem Reports (ETD)
Real-time health monitoring of high temperature systems (>500oC) in harsh environments is necessary to prevent catastrophic events caused by structural failures, varying pressure, and chemical reactions. Conventional solid-state temperature sensors such as resistance temperature detectors (RTDs) and thermocouples are restricted by their operating environments, sensor dimensions and often require external power sources for their operation. The current work presents the research and development of RF-based passive wireless sensing technology targeting high temperatures and harsh environmental conditions. Passive wireless devices are generally classified as near-field and far-field devices based on the interrogation distance. Near-field sensors are placed at …
