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The Relationship Between Electrical Conductivity And Magnetically Damped Motion, Kalem Akhtar 2018 Queensland Academy SMT

The Relationship Between Electrical Conductivity And Magnetically Damped Motion, Kalem Akhtar

The International Student Science Fair 2018

Varying electrical conductivities of different, non-magnetic metals appears to affect the magnitude of magnetically damped motion. To determine the relationship between magnetic damping and conductivity an experiment was designed using different length tubes of aluminium, copper and brass. The tubes had the same diameter and similar wall thickness. A short, cylindrical neodymium magnet was dropped through the tubes of and the time for the magnet to traverse the tube was recorded using a smartphone camera. These times allowed for the terminal velocity to be calculated for each metal length and the average terminal velocity for each metal was determined. This ...


Software Defined Radar For Vital Sign Detection, Chandler J. Bauder, James Bates, Steven Engel, James S. Tucker, Fangzhou Liu 2018 University of Tennessee, Knoxville

Software Defined Radar For Vital Sign Detection, Chandler J. Bauder, James Bates, Steven Engel, James S. Tucker, Fangzhou Liu

University of Tennessee Honors Thesis Projects

No abstract provided.


Analysis Of Photovoltaic Energy In The Eastern Kentucky Region And The Residential Financial Feasibility, Joshua A. Johnson 2018 Morehead State University

Analysis Of Photovoltaic Energy In The Eastern Kentucky Region And The Residential Financial Feasibility, Joshua A. Johnson

Morehead State Theses and Dissertations

A thesis proposal presented to the Faculty of the College of Business and Technology Morehead State University in partial fulfillment of the requirements for the Degree Master of Science by Joshua A. Johnson on April 25, 2018.


Simplified Numerical Models In Simulating Corona Discharge And Ehd Flows, Sara Mantach 2018 The University of Western Ontario

Simplified Numerical Models In Simulating Corona Discharge And Ehd Flows, Sara Mantach

Electronic Thesis and Dissertation Repository

Corona discharge is used in many practical applications. For designing and optimization of corona devices, the discharge phenomenon should be numerically simulated. Most often, the corona discharge model is simplified by neglecting the process dynamics and assuming a limited number of reactions and species. In the extreme case, monopolar corona models with just one species and no reactions are studied. However, there is a problem with determining boundary conditions for the space charge density. The simplest solution to this problem was suggested by Kaptzov, who hypothesized that the electric field on the electrode surface remains constant and equal to the ...


Experimental Testing Of A Metamaterial Slow Wave Structure For High-Power Microwave Generation, Kevin Aaron Shipman 2018 University of New Mexico - Main Campus

Experimental Testing Of A Metamaterial Slow Wave Structure For High-Power Microwave Generation, Kevin Aaron Shipman

Electrical and Computer Engineering ETDs

Experimental Testing of a Metamaterial Slow Wave Structure for High-Power Microwave Generation

by

Kevin Aaron Shipman

B.S., Exercise Science, University of New Mexico, 2008

A.S., Mathematics, San Juan College, 2014

M.S., Electrical Engineering, University of New Mexico, 2018

Abstract

A high-power L-band microwave source has been developed using a metamaterial (MTM) to produce a biperiodic double negative slow wave structure (SWS) for interaction with an electron beam. The beam is generated by a ~700 kV, ~6 kA short pulse (~ 10 ns) electron beam accelerator. The design of the metamaterial SWS (MSWS) consists of a cylindrical waveguide, loaded ...


An Exploration Of The Optical Detection Of Ionizing Radiation Utilizing Modern Optics Technology, Sean D. Fournier, Adam Hecht, Cassiano de Oliveira, Jeffrey B. Martin, Richard K. Harrison, Charles Potter 2018 The University of New Mexico, Sandia National Laboratories

An Exploration Of The Optical Detection Of Ionizing Radiation Utilizing Modern Optics Technology, Sean D. Fournier, Adam Hecht, Cassiano De Oliveira, Jeffrey B. Martin, Richard K. Harrison, Charles Potter

Nuclear Engineering ETDs

Modern ultraviolet (UV) cameras, when combined with UV-transmitting lenses/filter arrangements, can be used to detect radiation dose in air. Ionizing radiation excites nitrogen molecules in ambient air, the resulting decay includes weak emission of ultraviolet photons. Previous work has proven this phenomenon is detectable using highly-sensitive electronically cooled cameras traditionally used in astronomy for low-background imaging. While the ability to detect the presence of radiation (i.e. qualitative measurement) has been demonstrated at Sandia National Laboratories, there are several challenges in correlating images to known dose-fields (quantitative measurement). These challenges include: a low signal to background ratio, interferences due ...


Image Processing Applications In Real Life: 2d Fragmented Image And Document Reassembly And Frequency Division Multiplexed Imaging, Houman Kamran Habibkhani, Houman Kamran Habibkhani 2018 Louisiana State University

Image Processing Applications In Real Life: 2d Fragmented Image And Document Reassembly And Frequency Division Multiplexed Imaging, Houman Kamran Habibkhani, Houman Kamran Habibkhani

LSU Doctoral Dissertations

In this era of modern technology, image processing is one the most studied disciplines of signal processing and its applications can be found in every aspect of our daily life. In this work three main applications for image processing has been studied.

In chapter 1, frequency division multiplexed imaging (FDMI), a novel idea in the field of computational photography, has been introduced. Using FDMI, multiple images are captured simultaneously in a single shot and can later be extracted from the multiplexed image. This is achieved by spatially modulating the images so that they are placed at different locations in the ...


Non-Invasive Picosecond Pulse System For Electrostimulation, Ross Aaron Petrella 2018 Old Dominion University

Non-Invasive Picosecond Pulse System For Electrostimulation, Ross Aaron Petrella

Electrical & Computer Engineering Theses & Disssertations

Picosecond pulsed electric fields have been shown to have stimulatory effects, such as calcium influx, activation of action potential, and membrane depolarization, on biological cells. Because the pulse duration is so short, it has been hypothesized that the pulses permeate a cell and can directly affect intracellular cell structures by bypassing the shielding of the membrane. This provides an opportunity for studying new biophysics. Furthermore, radiating picosecond pulses can be efficiently done by a compact antenna because the antenna size is comparable to the pulse width. However, all of the previous bioelectric studies regarding picosecond pulses have been conducted in ...


Coaxial Magnetic Gearbox With A Flux Concentration Halbach Rotor And Consequent Pole Rotor Typology, Ho Yin Wong 2018 Portland State University

Coaxial Magnetic Gearbox With A Flux Concentration Halbach Rotor And Consequent Pole Rotor Typology, Ho Yin Wong

Electrical & Computer Engineering PhD Day

This paper presents the performance comparison between a flux concentration and triple permanent magnet consequent pole magnetic gear rotor typology with the same 7.5:1 gear ratio. The triple permanent magnet consequent pole magnetic gear is unique in that it can create torque change through two field heterodyning pole combinations. The performance with respect to volumetric and mass torque density is considered. It is shown that the flux concentration typology can operate with a higher mass and volumetric higher torque density, even when using a low flux concentration ratio rotor.


Antennas For Wv Band Applications, Firas Ayoub 2018 Doctoral Student, Electrical Engineering

Antennas For Wv Band Applications, Firas Ayoub

Electrical and Computer Engineering ETDs

This dissertation focuses on designing, fabricating and testing antennas that are suitable for operation within the V/W bands. In particular, this work focuses on the design of slotted rectangular waveguide antenna arrays and cross slotted waveguide fed horn antennas. These structures are known for their high efficiency and high circularly polarized gain that can be implemented in satellite and terrestrial communication links. In addition, such designs can be implemented in radar applications that operate infrequency bands around 72 GHz or 84 GHz bands. Such antenna structures are inexpensive to fabricate since they can simply be machined using high precision ...


Plasmonic Nanoplatforms For Biochemical Sensing And Medical Applications, Arash Ahmadivand 2018 Florida International University

Plasmonic Nanoplatforms For Biochemical Sensing And Medical Applications, Arash Ahmadivand

FIU Electronic Theses and Dissertations

Plasmonics, the science of the excitation of surface plasmon polaritons (SPP) at the metal-dielectric interface under intense beam radiation, has been studied for its immense potential for developing numerous nanophotonic devices, optical circuits and lab-on-a-chip devices. The key feature, which makes the plasmonic structures promising is the ability to support strong resonances with different behaviors and tunable localized hotspots, excitable in a wide spectral range. Therefore, the fundamental understanding of light-matter interactions at subwavelength nanostructures and use of this understanding to tailor plasmonic nanostructures with the ability to sustain high-quality tunable resonant modes are essential toward the realization of highly ...


Suppression Of Magnetostructural Transition On Gdsige Thin Film After Thermal Cyclings, A. L. Pires, J. H. Belo, I. T. Gomes, Ravi L. Hadimani, Deborah L. Schlagel, Thomas A. Lograsso, David C. Jiles, A. M. L. Lopes, J. P. Araújo, A. M. Pereira 2018 Universidade do Porto

Suppression Of Magnetostructural Transition On Gdsige Thin Film After Thermal Cyclings, A. L. Pires, J. H. Belo, I. T. Gomes, Ravi L. Hadimani, Deborah L. Schlagel, Thomas A. Lograsso, David C. Jiles, A. M. L. Lopes, J. P. Araújo, A. M. Pereira

Ravi L. Hadimani

The influence of thermal cycling on the microstructure, magnetic phase transition and magnetic entropy change of a Gd5Si1.3Ge2.7 thin film up to 1000 cycles is investigated. The authors found that after 1000 cycles a strong reduction of the crystallographic phase responsible for the magnetostructural transition (Orthorhombic II phase) occurs. This is attributed to chemical disorder, caused by the large number of expansion/compression cycles that the Orthorhombic II phase undergoes across the magnetostructural transition. The suppression of the magnetostructural transition corresponds to a drastic decrease of the thin film magnetic entropy change. These results reveal the importance of ...


Magnetic Interaction And Electronic Transport In La0.4bi0.6mn0.5ti0.5o3 Manganite, Vijaylakshmi Dayal, Punith Kumar V., Ravi L. Hadimani, E. A. Balfour, H. Fu, David C. Jiles 2018 Maharaja Institute of Technology Mysore

Magnetic Interaction And Electronic Transport In La0.4bi0.6mn0.5ti0.5o3 Manganite, Vijaylakshmi Dayal, Punith Kumar V., Ravi L. Hadimani, E. A. Balfour, H. Fu, David C. Jiles

Ravi L. Hadimani

We report magnetic interactions and electronic transport properties in La0.4Bi0.6Mn0.5Ti0.5O3 perovskite manganite synthesized using solid-state route. After characterizing the samples structurally, the systematic investigations of magnetic and electrical transport behaviors have been undertaken. It has been observed that at low temperatures near TC, the sample is magnetically frustrated leading to the second-order magnetic transition. A justification for the observed magnetic behavior has been explained based on Arrott's plot study. The resistivity as a function of temperature in the absence and the presence of applied magnetic field suggests semiconducting nature of the sample. The conduction of ...


Influence Of Mn Concentration On Magnetic Topological Insulator Mnxbi2−Xte3 Thin-Film Hall-Effect Sensor, Ravi L. Hadimani, S. Gupta, S. M. Harstad, Vitalij K. Pecharsky, David C. Jiles 2018 Iowa State University and Ames Laboratory

Influence Of Mn Concentration On Magnetic Topological Insulator Mnxbi2−Xte3 Thin-Film Hall-Effect Sensor, Ravi L. Hadimani, S. Gupta, S. M. Harstad, Vitalij K. Pecharsky, David C. Jiles

Ravi L. Hadimani

Hall-effect (HE) sensors based on high-quality Mn-doped Bi2Te3 topological insulator (TI) thin films have been systematically studied in this paper. Improvement of Hall sensitivity is found after doping the magnetic element Mn into Bi2Te3. The sensors with low Mn concentrations, MnxBi2-xTe3, x = 0.01 and 0.08 show the linear behavior of Hall resistance with sensitivity about 5 Ω/T. And their Hall sensitivity shows weak dependence on temperature. For sensors with high Mn concentration (x = 0.23), the Hall resistance with respect to magnetic field shows a hysteretic behavior. Moreover, its sensitivity shows almost eight times as high as ...


Annealing Influence On The Magnetostructural Transition In Gd5si1.3ge2.7 Thin Films, A. L. Pires, J. H. Belo, I. T. Gomes, R. L. Hadimani, David C. Jiles, L .Fernandes, P. B. Tavares, J. P. Araújo, A. M. L. Lopes, A. M. Pereira 2018 Universidade de Lisboa

Annealing Influence On The Magnetostructural Transition In Gd5si1.3ge2.7 Thin Films, A. L. Pires, J. H. Belo, I. T. Gomes, R. L. Hadimani, David C. Jiles, L .Fernandes, P. B. Tavares, J. P. Araújo, A. M. L. Lopes, A. M. Pereira

Ravi L. Hadimani

Due to the emerging cooling possibilities at the micro and nanoscale, such as the fast heat exchange rate, the effort to synthesize and optimize the magnetocaloric materials at these scales is rapidly growing. Here, we report the effect of different thermal treatments on Gd5Si1.3Ge2.7 thin film in order to evaluate the correlation between the crystal structure, magnetic phase transition and magnetocaloric effect. For annealing temperatures higher than 773 K, the samples showed a typical paramagnetic behavior. On the other hand, annealing below 773 K promoted the suppression of the magnetostructural transition at 190 K, while the magnetic transition ...


Antimatched Electromagnetic Metasurfaces For Broadband Arbitrary Phase Manipulation In Reflection, Odysseas Tsilipakos, Thomas Koschny, Costas M. Soukoulis 2018 Foundation for Research and Technology-Hellas

Antimatched Electromagnetic Metasurfaces For Broadband Arbitrary Phase Manipulation In Reflection, Odysseas Tsilipakos, Thomas Koschny, Costas M. Soukoulis

Ames Laboratory Accepted Manuscripts

Metasurfaces impart phase discontinuities on impinging electromagnetic waves that are typically limited to 0–2π. Here, we demonstrate that multiresonant metasurfaces can break free from this limitation and supply arbitrarily large, tunable time delays over ultrawide bandwidths. As such, ultrathin metasurfaces can act as the equivalent of thick bulk structures by emulating the multiple geometric resonances of three-dimensional systems that originate from phase accumulation with effective material resonances implemented on the surface itself via suitable subwavelength meta-atoms. We describe a constructive procedure for defining the required sheet admittivities of such metasurfaces. Importantly, the proposed approach provides an exactly linear phase ...


The Silver Lining: A Novel, Inkjet-Printed Mesh Coplanar-Slot Antenna For The Uhf Band, Anastasios C. Karles 2018 Virginia Commonwealth University

The Silver Lining: A Novel, Inkjet-Printed Mesh Coplanar-Slot Antenna For The Uhf Band, Anastasios C. Karles

Undergraduate Research Posters

The Federal Communications Commission (FCC) is opening up frequencies within the television range (400MHz to 700MHz) of the Ultra High Frequency (UHF) band for use in emerging technologies, such as cognitive radio networks and machine-to-machine communication. In order for manufacturers to produce affordable antennas that can be used in these emerging technologies, inexpensive antennas are required that meet these new spectrum needs. This paper presents a mesh coplanar-slot bowtie patch antenna fabricated using commercially available inkjet-printing technology. Two antennas were fabricated: a 27x21cm copper FR4 antenna with .25mm lines and a 27x21cm silver antenna with 2mm lines fabricated using inkjet-printing ...


High-Order Integral Equation Methods For Quasi-Magnetostatic And Corrosion-Related Field Analysis With Maritime Applications, Robert Pfeiffer 2018 University of Kentucky

High-Order Integral Equation Methods For Quasi-Magnetostatic And Corrosion-Related Field Analysis With Maritime Applications, Robert Pfeiffer

Theses and Dissertations--Electrical and Computer Engineering

This dissertation presents techniques for high-order simulation of electromagnetic fields, particularly for problems involving ships with ferromagnetic hulls and active corrosion-protection systems.

A set of numerically constrained hexahedral basis functions for volume integral equation discretization is presented in a method-of-moments context. Test simulations demonstrate the accuracy achievable with these functions as well as the improvement brought about in system conditioning when compared to other basis sets.

A general method for converting between a locally-corrected Nyström discretization of an integral equation and a method-of-moments discretization is presented next. Several problems involving conducting and magnetic-conducting materials are solved to verify the accuracy ...


A Rectenna For 5g Energy Harvesting, Panagiotis Efthymakis 2018 efthymakisp

A Rectenna For 5g Energy Harvesting, Panagiotis Efthymakis

Theses and Dissertations

This thesis describes the design of a rectenna that is capable of operating in 5G. 5G’s availability will create the opportunity to harvest energy everywhere in the network’s coverage. This thesis investigates a Rectenna device with a new proposed topology in order to eliminate coupling between input and output lines and increase the rectification efficiency. Moreover, it is designed to charge a rechargeable battery of 3V, 1mA, with a 4.8mm diameter. The current design describes using one antenna for energy harvesting; this could be expanded to use an antenna array, which would increase the input power. This ...


Precision Radio-Frequency And Microwave Dielectric Spectroscopy And Characterization Of Ionic Aqueous Solutions, Amin Gorji-Bandpy 2018 Iowa State University

Precision Radio-Frequency And Microwave Dielectric Spectroscopy And Characterization Of Ionic Aqueous Solutions, Amin Gorji-Bandpy

Graduate Theses and Dissertations

Excessive amounts of chemicals and ions flowing into water sources, which are mainly due to efflux from agricultural lands, cause serious environmental and human-health related concerns. The lack of affordable and real-time monitoring systems for these contaminants limits effective conservation and management strategies. To establish a basis for developing an effective, fast, real-time, and affordable sensing system, dielectric spectroscopy has been applied to characterize agriculturally-relevant aqueous solutions of most commonly found ions in tile drainage water. Dielectric spectra of aqueous sodium chloride (NaCl), sodium nitrate (NaNO3), and sodium sulphate (Na2SO4) ionic solutions, which are the common pollutants found in agricultural ...


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