Electromagnetic polarization systems and methods Patent
Left and right hand circular electromagnetic polarization excitation by phase shifter and hybrid networks
Taylor, R. E.↗
SEARCH · Engineering Papers
Results for “Methods in electromagnetism”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Electromagnetic field-assisted method for chemical conversion
Embodiments relate to methods for enhancing chemical conversions. One or more embodiments relate to a method for enhancing a multi-step chemical conversion reaction. The method includes providing a reactant mixture comprising one or more reacting specie(s); and providing a catalyst or sorbent comprising one or more support materials and one or more deposited catalytically active materials. The method further includes applying an electromagnetic field with a prescribed power, frequency, and pulsing strategy specific to interactions of reactant species and an electromagnetic field with at least one of the support materials, sorbent, and catalytically active materials in a particular chemical reaction.
Shekhawat, Dushyant↗
Method and apparatus for measuring electromagnetic radiation
An apparatus and method are described in which the capacitance of a semiconductor junction subjected to an electromagnetic radiation field is utilized to indicate the intensity or strength of the radiation.
Been, J. F.↗
Observing and modeling the effects of production infrastructure in electromagnetic surveys
Electromagnetic (EM) methods are among the original techniques for subsurface characterization in exploration geophysics because of their particular sensitivity to the earth electrical conductivity, a physical property of rocks distinct yet complementary to density, magnetization, and strength. However, this unique ability also makes them sensitive to metallic artifacts — infrastructure such as pipes, cables, and other forms of cultural clutter — the EM footprint of which often far exceeds their diminutive stature when compared to that of bulk rock itself. In the hunt for buried treasure or unexploded ordnance, this is an advantage; in the long-term monitoring of mature oil fields after decades of production, it is quite troublesome indeed. In this study we consider the latter through the lens of an evolving energy industry landscape in which the traditional methods of EM characterization for the exploration geophysicist are applied toward emergent problems in well-casing integrity, carbon capture and storage, and overall situational awareness in the oil field. We introduce case studies from these exemplars, showing how signals from metallic artifacts can dominate those from the target itself and impose significant burdens on the requisite simulation complexity. Furthermore, we show how recent advances in numerical methods mitigate the computational explosivity of infrastructure modeling, providing feasible and real-time analysis tools for the desktop geophysicist. Lastly, we demonstrate through comparison of field data and simulation results that incorporation of infrastructure into the analysis of such geophysical data is, in a growing number of cases, a requisite but now manageable step.
58 GEOSCIENCES↗
State-of-the-art methods for computing the electromagnetic interaction of lightning with aircraft
Nuclear electromagnetic pulse (NEMP) coupling codes and methods are evaluated and summarized. The differences between NEMP and lightning interaction with aircraft are discussed and critical parameters peculiar to lightning are examined.
Eriksen, F. J.↗
New Methods to Determine the Electromagnetic Effects from Precipitation Static
The Electrostatics and Surface Physic Laboratory has devised a new method to determine the electromagnetic effects from precipitation static or p-static as its commonly called. P-static occurs as a result of triboelectric charging of granular materials or ice crystals bombarded onto the surfaces of air and/or space vehicles at high speeds. The electrostatic charge that builds up on the outer surface can have deleterious effects that arise during discharge events. These discharges can cause loss of communication to and from the vehicle from ground stations, EMI interference, radio frequency noise, etc… There are even cases of total loss of vehicles caused by p-static charging. We have developed a method to simulate the extensive tribocharging of insulating materials that occurs during p-static through the use of corona charging which allows testing to occur within a lab environment. These tests simulate the discharges that occur on rocket vehicles during ascent as a result of gas breakdown by performing the corona charging tests inside a vacuum chamber and subsequently removing the air. The simultaneous gas discharges emit electromagnetic interference (EMI) which can be captured and monitored.
Charles R Buhler↗
A hybrid nodal-staggered pseudo-spectral electromagnetic particle-in-cell method with finite-order centering
Electromagnetic particle-in-cell (PIC) codes are widely used to perform computer simulations of a variety of physical systems, including fusion plasmas, astrophysical plasmas, plasma wakefield particle accelerators, and secondary photon sources driven by ultra-intense lasers. In a PIC code, Maxwell's equations are solved on a grid with a numerical method of choice. This article focuses on pseudo-spectral analytical time-domain (PSATD) algorithms and presents a novel hybrid PSATD PIC scheme that combines the respective advantages of standard nodal and staggered methods. The novelty of the hybrid scheme consists in using finite-order centering of grid quantities between nodal and staggered grids, in order to combine the solution of Maxwell's equations on a staggered grid with the deposition of charges and currents and the gathering of electromagnetic forces on a nodal grid. The correctness and performance of the novel hybrid scheme are assessed by means of numerical tests that employ different classes of PSATD equations in a variety of physical scenarios, ranging from the modeling of electron-positron pair creation in vacuum to the simulation of laser-driven and particle beam-driven plasma wakefield acceleration. It is shown that the novel hybrid scheme offers significant numerical and computational advantages, compared to purely nodal or staggered methods, for all the test cases presented.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Method-Of-Moments Code For Electromagnetic Scattering
MOM3D computer program implementing method-of-moments algorithm for analysis of electromagnetic waves on open or closed three-dimensional, perfectly conducting or resistive surfaces. Primary emphasis in analysis upon computation of radar cross section under plane-wave illumination. Also provides for excitation via local ports for computation of gain patterns and input impedances of antennas. Written in FORTRAN 77. Two machine versions available. One, UNIX version (LAR-15074). Other, IBM PC version (LAR-15130). UNIX version also available as part of package, COS-10048, includes EM-ANIMATE, IRIS program capable of displaying and animating MOM3D results.
Shaeffer, John F.↗
Methods and systems for electromagnetic near-field coherent sensing
The present disclosure may be embodied as methods and/or systems for non-contact measuring of an on-body and/or inside-body motion of an individual. A sensing signal is provided within a near-field coupling range of a motion to be measured. In this way, a measurement signal may be generated as the sensing signal modulated by the motion. The sensing signal may be an ID-modulated signal. In some embodiments, the sensing signal is a backscattered RFID link provided a wireless tag. A downlink signal may be provided to power the wireless tag. The sensing signal may be a harmonic of the downlink signal. The measurement signal is detected. The motion is measured based on the measurement signal. The measurement signal may be detected as far-field radiation after transmission through a source of the motion. The measurement signal may be detected as reflected from a source of the motion as antenna reflection.
Hui, Xiaonan↗
SREMI: Super-resolution electromagnetic imaging with single-channel ground-penetrating radar
High-resolution near-surface imaging has important applications in civil engineering, infrastructure inspection, military threat detection, geological characterization, and lunar and planetary exploration. Zero-offset, singlechannel ground penetrating radar (GPR) imaging is an established technique for near-surface target imaging and sensing but often suffers from low spatial resolution and imaging artifacts, especially of deep structures. In response, we formulate the GPR imaging as a dual-sparsity optimization problem, and develop a super-resolution electromagnetic imaging method based on a fast iterative shrinkage-thresholding algorithm. We develop our GPR imaging method in the framework of electromagnetic exploding-reflectors simulation theory, therefore the imaging method is computationally efficient. In this work, we demonstrate through synthetic and field data examples that our method can produce sharper, more reliable images with fewer artifacts compared with single-pass reverse-time migration GPR method, thus leading to improved near-surface interpretation and object identification.
58 GEOSCIENCES↗
Rolled-up electromagnetic component for on-chip applications and method of making a rolled-up electromagnetic component
A rolled-up electromagnetic component for on-chip applications comprises: a multilayer sheet in a rolled configuration comprising at least one turn about a longitudinal axis; a core defined by a first turn of the rolled configuration; and a soft magnetic material disposed within the core, where the multilayer sheet comprises a conductive pattern layer on a strain-relieved layer. A method of making a rolled-up electromagnetic component for on-chip applications includes forming a rolled-up device comprising: a multilayer sheet in a rolled configuration having at least one turn about a longitudinal axis, where the multilayer sheet comprises a conductive pattern layer on a strain-relieved layer; and a core defined by a first turn of the rolled configuration. The method further includes introducing a soft magnetic material into the core.
Li, Xiuling↗
Electromagnetic Radioisotope Separator for Methods Development, Testing, and Training
The major goal of the project is the construction and operation of an electromagnetic isotope separator. Included in that goal is the construction and installation of a high throughput surface ion source, with specific applicability to the Lanthanides. The surface ion source features a single-piece titanium crucible insert that mates with a tantalum hot surface ionizer. The titanium crucible, which does not readily activate, can be loaded with samarium and then irradiated simultaneously, greatly reducing operator dose.
07 ISOTOPE AND RADIATION SOURCES↗
Parallel decomposition methods for the solution of electromagnetic scattering problems
This paper contains a overview of the methods used in decomposing solutions to scattering problems onto coarse-grained parallel processors. Initially, a short summary of relevant computer architecture is presented as background to the subsequent discussion. After the introduction of a programming model for problem decomposition, specific decompositions of finite difference time domain, finite element, and integral equation solutions to Maxwell's equations are presented. The paper concludes with an outline of possible software-assisted decomposition methods and a summary.
Cwik, Tom↗
Wave propagation and turbulent media.
Book on electromagnetic wave propagation and turbulent media covering invariant imbedding method, turbulence generation, statistical methods of analysis, etc
INVARIANT IMBEDDING↗
A stable potential-based time-domain method for wideband elec- tromagnetic analysis
In previous research, the frequency-domain A-ϕ formulation has been validated using the finite element method for electromagnetic simulations of low-frequency and multi- scale problems, demonstrating excellent numerical accuracy, good matrix condition, and high computational efficiency. Time- domain simulations provide significant advantages for modeling wideband problems and are crucial for multiphysics applications. In this paper, the frequency-domain A-ϕ formulation is extended to the time domain. The central difference scheme is employed for temporal discretization to ensure both accuracy and stability. A numerical example is presented to demonstrate the capability of the proposed time-domain method in wideband electromagnetic analysis.
Mekonnen, Minyichil↗
Electromagnetic Shower Reconstruction and Identification in FASER's Emulsion Detector for LHC Forward Neutrino Measurements
We present methods for electromagnetic shower reconstruction and identification in the FASERnu emulsion detector using 100 GeV and 200 GeV electron test-beam data from the CERN SPS H4 beamline. The reconstruction employs a clustering-based algorithm without energy-dependent tuning to determine shower axes. A multi-level identification chain comprising track pre-selection, a cut-based selection, and a BDT classifier achieves combined background rejection rates of 99.99% (100 GeV) and 99.94% (200 GeV). The method reaches total reconstruction and identification efficiencies of 58.9% (100 GeV) and 70.8% (200 GeV) evaluated from simulated samples. Energy reconstruction using the total number of reconstructed segments as the calorimetric estimator yields relative biases of +0.6% (100 GeV) and -0.8% (200 GeV), with resolutions of 25.4% and 22.6%, respectively. Systematic uncertainties on the energy reconstruction are dominated by variations in emulsion film detection efficiency, contributing (+10.9%/-8.2%) at 100 GeV and (+10.3%/-6.9%) at 200 GeV. The methodology provides a validated framework for electron neutrino identification with the FASERnu detector at the LHC.
Mammen Abraham, Roshan [UC, Irvine]↗
1985 International Geoscience and Remote Sensing Symposium (IGARSS '85), University of Massachusetts, Amherst, October 7-9, 1985, Digest. Volumes 1 & 2
The present conference on remote sensing instrumentation considers topics in water resources research, planetary remote sensing and mathematical geophysics, sea ice behavior in view of the Cold Regions Research and Engineering Laboratories pond measurements, Shuttle Imaging Radar-B (SIR-B) system performance and calibration results, geological applications of remote sensing, and microwave scattering from vegetation. Further attention is given to atmospheric probing with lasers, image processing for remote sensing, forest inventory and condition assessment, atmospheric remote sensing, SIR-B geological results, the reflectance, emission, and scattering characteristics of vegetation, sea ice sensing, multipolarization SAR results, the theoretical modeling of surfaces and volumes, crop condition assessment and productivity estimates, and SIR-B results for vegetation cover. Also considered are the microwave remote sensing of soil moisture, advanced sensors, advanced information extraction, wind and wave remote observations, results from the ESA Remote Sensing satellite, large area crop and land cover statistics, SIR-B results for directional ocean wave spectra, seasonal snow cover, ice sheets, and lake ice, fundamental research in terrain remote sensing, image classification methods, vegetation stress detection, remote sensing of coastal processes, SAR systems and calibration, electromagnetic geophysical methods and signal processing, image processing techniques, and SAR internal wave measurements.
Carver, K. R.↗