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Electromagnetics and Photonics Commons

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Numerical Modeling Of Magnetic Fields For Mirror Neutron Search Experiment, Adam Johnston 2020 University of Tennessee, Knoxville

Numerical Modeling Of Magnetic Fields For Mirror Neutron Search Experiment, Adam Johnston

Pursuit - The Journal of Undergraduate Research at the University of Tennessee

This paper will outline the configuration of 3D magnetic field model simulated from electric current sources using MATLAB. The model is using 3D arrays allowing for quick and accurate numerical approximations of Bio-Savart integrals, of error < , modeling the behavior of a magnetic field due to current carrying wires. We will discuss the development of a 3D magnetic field configuration produced by the current carrying wires around a large 2.5 m diameter vacuum beam tube in the proposed mirror neutron search experiment at High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL). The simulations demonstrate that the magnetic field with uniformity better than ± 2.5 mG that will allow for optimal results in experiment within the controlled range of net magnetic field magnitudes |B| 500 mG and in the large vacuum tube along 20-m neutron flight path can be achieved for an approximately 6 cm radius section at the center of the tube.


Development And Test Of High Temperature Surface Acoustic Wave Gas Sensors, Armando E. Ayes Moncada 2020 University of Maine

Development And Test Of High Temperature Surface Acoustic Wave Gas Sensors, Armando E. Ayes Moncada

Electronic Theses and Dissertations

The demand for sensors in hostile environments, such as power plant environments, exhaust systems and high-temperature metallurgy environments, has risen over the past decades in a continuous attempt to increase process control, improve energy and process efficiency in production, reduce operational and maintenance costs, increase safety, and perform condition-based maintenance in equipment and structures operating in high-temperature, harsh-environment conditions. The increased reliability, improved performance, and development of new sensors and networks with a multitude of components, especially wireless networks, are the target for operation in harsh environments. Gas sensors, in particular hydrogen gas sensors, operating above 200°C are required ...


Design And Verification Of Search Coil Inductance For Pulse Induction Metal Detection, David Desrochers 2020 University of Arkansas, Fayetteville

Design And Verification Of Search Coil Inductance For Pulse Induction Metal Detection, David Desrochers

Electrical Engineering Undergraduate Honors Theses

As violent attacks have increased at different venues such as schools, the need for affordable and effective metallic weapon detection has increased. Probing and scanning detection wands are the most common seen in use by guards. This project seeks to combine both probing and scanning coils into one pulse induction metal detector. The use of one drive circuit for both LC coil tank circuits further economizes the system. ANSYS Maxwell electromagnetic simulations are used to develop the geometries needed for sensitive metal detection. Analytical, simulation, and experimental methods are used to first verify the design flow for solenoid inductors. These ...


Early Warning Solar Storm Prediction, Ian D. Lumsden, Marvin Joshi, Matthew Smalley, Aiden Rutter, Ben Klein 2020 University of Tennessee, Knoxville

Early Warning Solar Storm Prediction, Ian D. Lumsden, Marvin Joshi, Matthew Smalley, Aiden Rutter, Ben Klein

Chancellor’s Honors Program Projects

No abstract provided.


Single-Pulse, Kerr-Effect Mueller Matrix Lidar Polarimeter, Keyser, Christian K., Richard K. Martin, Helena Lopez-Aviles, Khanh Nguyen, Arielle M. Adams, Demetrios Christodoulides 2020 Air Force Institute of Technology

Single-Pulse, Kerr-Effect Mueller Matrix Lidar Polarimeter, Keyser, Christian K., Richard K. Martin, Helena Lopez-Aviles, Khanh Nguyen, Arielle M. Adams, Demetrios Christodoulides

Faculty Publications

We present a novel light detection and ranging (LiDAR) polarimeter that enables measurement of 12 of 16 sample Mueller matrix elements in a single, 10 ns pulse. The new polarization state generator (PSG) leverages Kerr phase modulation in a birefringent optical fiber, creating a probe pulse characterized by temporally varying polarization. Theoretical expressions for the Polarization State Generator (PSG) Stokes vector are derived for birefringent walk-off and no walk-off and incorporated into a time-dependent polarimeter signal model employing multiple polarization state analyzers (PSA). Polarimeter modeling compares the Kerr effect and electro-optic phase modulator–based PSG using a single Polarization State ...


Anti-Jam Gps Controlled Reception Pattern Antennas For Man-Portable Applications, Jeffrey A. Maloney 2020 University of Massachusetts Amherst

Anti-Jam Gps Controlled Reception Pattern Antennas For Man-Portable Applications, Jeffrey A. Maloney

Doctoral Dissertations

Military GPS receivers provide crucial information to soldiers in the field, however, the performance of these devices is degraded by in band RF interference, making GPS susceptible to jamming. Anti-jam techniques for aircraft and vehicular platforms have been developed, but at present there is no system for dismounted soldiers. There is a need for an anti-jam system which meets the demands of a dismounted soldier and conforms to the size, weight, and power requirements of a portable device.

A controlled reception pattern antenna, or CRPA, is a potential solution for jammer mitigation. These devices work by steering reception pattern nulls ...


Dynamic Micromechanical Fabry-Perot Cavity Sensors Fabricated By Multiphoton Absorption Onto Optical Fiber Tips, Jeremiah C. Williams 2020 Air Force Institute of Technology

Dynamic Micromechanical Fabry-Perot Cavity Sensors Fabricated By Multiphoton Absorption Onto Optical Fiber Tips, Jeremiah C. Williams

Theses and Dissertations

This research leveraged two-photon polymerization microfabrication to integrate dynamic mechanical components with Fabry-Perot resonators onto the ends of low-loss optical fibers to prototype 3 micro-optic devices. The first device featured a multi-positional mirror that enabled thin-film deposition onto cavities of any length with mirrors of significant curvature, for refractive index sensing. The second device combined an FP cavity with a spring body featuring easily scalable stiffness for pressure sensing. The third device presented a high-speed rotating micro-anemometer for measuring a wide range of gas flows. All devices represent a significant reduction in size and weight over commercially available devices.


Characterization And Sensitivity Analysis Of 6 Meter Cassegrain Antenna, James L. Harris 2020 Air Force Institute of Technology

Characterization And Sensitivity Analysis Of 6 Meter Cassegrain Antenna, James L. Harris

Theses and Dissertations

This paper will characterize a 6 meter in diameter cassegrain antenna. The cassegrain antenna is a special form of a dual reflector antenna which uses a main reflector following a parabolic curve and a sub reflector which follows a hyperbolic curve. Cassegrain style antennas have multiple parameters which can be tuned to achieve specific design goals. Performing a sensitivity analysis will establish relationships between design parameters, directivity, side lobe levels, and effects of strut geometry. The initial design parameters will be assumed based on typical values. Results from the sensitivity analysis will be used to provide a performance band for ...


Focused Beam System Biaxial Material Characterization, Nicholas A. O'Gorman 2020 Air Force Institute of Technology

Focused Beam System Biaxial Material Characterization, Nicholas A. O'Gorman

Theses and Dissertations

Electromagnetic material characterization is the process of determining the constitutive parameters (complex permittivity and permeability) of given a sample. Due to the large number of unknowns involved, multiple unique measurements are required for material property extraction. Many measurement methods, such as waveguides and striplines, possess a rigid internal structure that the sample being measured must adhere to. This rigidity limits these methods to samples that fit within the device and inhibits oblique sample orientations, limiting the number of independent measurements that can be obtained. A focus beam system, due to being an open system with greater freedom in sample size ...


Bandwidth Bounds Of Infinite Planar Array Elements, Hsieh-Chi Chang 2020 University of Massachusetts Amherst

Bandwidth Bounds Of Infinite Planar Array Elements, Hsieh-Chi Chang

Doctoral Dissertations

For elements of an infinite planar phased array in free space and an infinite conductor-backed free standing planar phased array, fundamental bandwidth bounds are derived from the optical theorem for periodic scatterers. The bounds are based on Gustafsson’s theory of fundamental bandwidth limits for electrically small antennas of arbitrary shape, but extended to periodic configurations. The element bandwidth bound is found to be a function of the strengths of the induced static dipole moments in constant background fields as well as the unit-cell dimensions and the scan angle. Explicit bandwidth bound expressions are found for narrowband and ultrawideband array ...


Syllabus Ee330 Electromagnetics, Nicholas Madamopoulos 2020 CUNY City College

Syllabus Ee330 Electromagnetics, Nicholas Madamopoulos

Open Educational Resources

Concepts covered in the undergraduate electrical engineering class of electromagnetics


Synthesizing General Electromagnetic Partially Coherent Sources From Random, Correlated Complex Screens, Milo W. Hyde IV 2020 Air Force Institute of Technology

Synthesizing General Electromagnetic Partially Coherent Sources From Random, Correlated Complex Screens, Milo W. Hyde Iv

Faculty Publications

We present a method to generate any genuine electromagnetic partially coherent source (PCS) from correlated, stochastic complex screens. The method described here can be directly implemented on existing spatial-light-modulator-based vector beam generators and can be used in any application which utilizes electromagnetic PCSs. Our method is based on the genuine cross-spectral density matrix criterion. Applying that criterion, we show that stochastic vector field realizations (corresponding to a desired electromagnetic PCS) can be generated by passing correlated Gaussian random numbers through “filters” with space-variant transfer functions. We include step-by-step instructions on how to generate the electromagnetic PCS field realizations. As an ...


Detection Of Reconnection Signatures In Solar Flares, Taylor R. Whitney 2020 Air Force Institute of Technology

Detection Of Reconnection Signatures In Solar Flares, Taylor R. Whitney

Theses and Dissertations

Solar flare forecasting is limited by the current understanding of mechanisms that govern magnetic reconnection, the main physical phenomenon associated with these events. As a result, forecasting relies mainly on climatological correlations to historical events rather than the underlying physics principles. Solar physics models place the neutral point of the reconnection event in the solar corona. Correspondingly, studies of photospheric magnetic fields indicate changes during solar flares -- particularly in relation to the field helicity -- on the solar surface as a result of the associated magnetic reconnection. This study utilizes data from the Solar Dynamics Observatory (SDO) Helioseismic and Magnetic Imager ...


Design Of Monophasic Pulsed Magnetic Fields For Use In Low Bias Fields, Neelam Prabhu-Gaunkar, Wei S. Theh, R.J. Weber, Mani Mina 2020 Iowa State University

Design Of Monophasic Pulsed Magnetic Fields For Use In Low Bias Fields, Neelam Prabhu-Gaunkar, Wei S. Theh, R.J. Weber, Mani Mina

Industrial Design Publications

In this work, the design of a pulsed magnetic field generator, with user-selective pulsed modulation frequency is described. The ability to operate at various frequencies (single-frequency below 10 MHz) makes the system valuable to several areas such as medical treatments and pulsed switching systems. In this work, the pulsed magnetic field generator is designed to create localized field effects in portable magnetic resonance systems. Users may operate at a Larmor precession frequency between 100 kHz - 10 MHz and can achieve high currents through the load. Certain tunability can also be obtained by varying the load inductance or switching device conditions ...


Wireless Underground Communications In Sewer And Stormwater Overflow Monitoring: Radio Waves Through Soil And Asphalt Medium, Usman Raza, Abdul Salam 2020 Purdue University

Wireless Underground Communications In Sewer And Stormwater Overflow Monitoring: Radio Waves Through Soil And Asphalt Medium, Usman Raza, Abdul Salam

Faculty Publications

Storm drains and sanitary sewers are prone to backups and overflows due to extra amount wastewater entering the pipes. To prevent that, it is imperative to efficiently monitor the urban underground infrastructure. The combination of sensors system and wireless underground communication system can be used to realize urban underground IoT applications, e.g., storm water and wastewater overflow monitoring systems. The aim of this article is to establish a feasibility of the use of wireless underground communications techniques, and wave propagation through the subsurface soil and asphalt layers, in an underground pavement system for storm water and sewer overflow monitoring ...


Generating Electromagnetic Dark And Antidark Partially Coherent Sources, Milo W. Hyde IV 2020 Air Force Institute of Technology

Generating Electromagnetic Dark And Antidark Partially Coherent Sources, Milo W. Hyde Iv

Faculty Publications

We present two methods to generate an electromagnetic dark and antidark partially coherent source. The first generalizes a recently published scalar approach by representing the stochastic electric field vector components as sums of randomly weighted, randomly tilted plane waves. The second method expands the field’s vector components in series of randomly weighted dark and antidark coherent modes. The statistical moments of the random weights—plane waves in the former method, coherent modes in the latter—are found by comparing the resulting means and covariances to those of the desired electromagnetic dark and antidark source. We validate both methods by ...


Levitate, Stephen Hargreaves, Isaac Hammonds, Russel Pease, Joseph Morris 2020 Computer Engineering

Levitate, Stephen Hargreaves, Isaac Hammonds, Russel Pease, Joseph Morris

Williams Honors College, Honors Research Projects

Levitate is designed to create a healthier work environment by providing a way of entertaining a worker while not distracting them. To fulfill this task, the device needs to be interesting and self-sufficient while not being overly flashy. To complete this task, Levitate is designed so that it is able to lift a platform from rest using magnetism and that will be able to stabilize itself using electromagnets. It initiates this process by lifting the permanent magnet using servo motors. Then, the device is able to achieve stability through the use of hall sensors feeding their results to the board ...


Kettlebell Ultra, Elissa Peters, Kathryn Wegman, Daniel Basch, Mason Pastorius 2020 The University of Akron

Kettlebell Ultra, Elissa Peters, Kathryn Wegman, Daniel Basch, Mason Pastorius

Williams Honors College, Honors Research Projects

This project will consist of an attachment to an average kettlebell that will track the number of repetitions that the user has performed. The device will send this data over Bluetooth to a smart phone application so the user can track their workout accurately.


Parallelized X-Ray Tracing With Gpu Ray-Tracing Engine, Joseph Ulseth 2020 University of Central Florida

Parallelized X-Ray Tracing With Gpu Ray-Tracing Engine, Joseph Ulseth

Electronic Theses and Dissertations, 2020-

X-ray diffraction tomography (XDT) is used to probe material composition of objects, providing improved contrast between materials compared to conventional transmission based computed tomography (CT). In this work, a small angle approximation to Bragg's Equation of diffraction is coupled with parallelized computing using Graphics Processing Units (GPUs) to accelerate XDT simulations. The approximation gives rise to a simple yet useful proportionality between momentum transfer, radial distance of diffracted signal with respect to incoming beam's location, and depth of material, so that ray tracing may be parallelized. NVIDIA's OptiX ray-tracing engine, a parallelized pipeline for GPUs, is employed ...


High-Fidelity Mini-Led And Micro-Led Displays, Yuge Huang 2020 University of Central Florida

High-Fidelity Mini-Led And Micro-Led Displays, Yuge Huang

Electronic Theses and Dissertations, 2020-

Mini-LED and micro-LED are emerging disruptive display technologies, because they can work as local dimmable backlight to significantly enhance the dynamic range of conventional LCDs, or as sunlight readable emissive displays. However, there are still unresolved issues impairing their display fidelity: 1) motion blur on high-resolution, large-size and high-luminance devices, 2) limited contrast ratio on mini-LED backlit LCD (mLED-LCD), 3) relatively high power consumption, and 4) compromised ambient contrast ratio. This dissertation tackles with each of these issues for achieving high display fidelity. Motion blur is caused by slow liquid crystal response time and image update delays. Low-duty ratio operation ...


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