Complex Electromagnetic Field Research Articles

Solution of Maxwell's Equations for the Simulation and Optimization of the Radar Assessment of Concrete Structures

Recent developments in ground-penetrating radar (GPR) models have brought about complex electromagnetic fields due to the fine variations of structures. Therefore, it has become necessary to use more accurate analysis including environmental characteristics, antennas, and interpretation of the raw data in three-dimensional space. Such analyses require numerical techniques by which problems having complex scattering properties can be solved as accurately and as fast as possible. Some methods had been developed for resolution of specific problems involving differential or integral equations. However, each technique has limitations and trade-offs. The research work presented in this article aims to develop electromagnetic wave-propagation models in concrete structures using different numerical techniques to investigate the detection and location of buried objects.

NEW FINITE ELEMENT METHOD OF ELECTROMAGNETIC CALCULATION FOR COMPLEX ELECTROMAGNETIC FIELDS

In order to increase greatly the calculation accuracy and the computation speed for complex electromagnetic fields in modern physics, a new finite element method, which has the high computation accuracy, fast computation speed and less computer storage requirements, is presented in this paper. The new method with a high-order finite element without internal nodes is introduced to compute and analyze some complex electromagnetic fields in the electron accelerators. In this paper, the complex electromagnetic field in an electromagnetic device has been calculated successfully by the finite elements, and the electromagnetic properties of the electromagnetic device under the specific work condition is analyzed and evaluated. Good agreement is found between the computed values and the experimental values.

Photon states from propagating complex electromagnetic fields

A wave function for single- and many-photon states is defined by associating photons with different momenta with different spectral and polarization components of the classical, generally complex, electromagnetic field that propagates in a definite direction. When each spectral component of the classical field is scaled to the square root of the photon energy, the appropriately normalized photon wave function acquires the desired interpretation of probability density amplitude, in contradistinction to the Riemann-Silberstein wave function that can be considered the amplitude of the photon probability energy density.

A THEORY OF NEUROPHYSICS AND QUANTUM NEUROSCIENCE: IMPLICATIONS FOR BRAIN FUNCTION AND THE LIMITS OF CONSCIOUSNESS

The authors have assumed there are specific temporal patterns of complex electromagnetic fields that can access and affect all levels of brain space. The article presents formulae and results that might reveal the required field configurations to obtain this access and to represent these levels in human consciousness. The frequency for the transition from an imaginary to real solution for the four-dimensional human brain was the wavelength of hydrogen whereas the optimal distance in space was the width of a proton or electron. The time required to expand one Planck's length as inferred by Hubble's constant for the proton was about 1 to 3 ms, the optimal resonant “point duration” of our most bioeffective magnetic fields. Calculations indicated the volume of a proton is equivalent to a tube or string with the radius of Planck's length and the longitudinal length of m (the width of the universe). Solutions from this approach predicted the characteristics of many biological phenomena, seven more “dimensions” of space between Planck's length and the level of the proton, and an inflection point between increments of space and time that corresponded to the distances occupied by chemical bonds. The multiple congruencies of the solutions suggest that brain space could contain inordinately large amounts of information reflecting the nature of extraordinarily large increments of space and time.

C206 準解析的手法による高周波電流分布の可視化

To visualize the electromagnetic fields, we have previously proposed a semi-analytical method, which has made it possible to simulate the complex electromagnetic field distributions not obtain by the conventional numerical schemes, such as finite elements and boundary elements means. Distinguished superior point of our semi-analytical method is that our semi-analytical method is only one way solving for the electromagnetic field, conducting and displacement currents simultaneously.In this paper, we propose a new semi-analytical approach to visualize the eddy current distribution in a two-dimensional plate, Successful result of this computation promises that eddy current testing may be carried out taking into account the displacement current, i.e., capacitive, effects.

The effect of MBST®-NuclearResonanceTherapy with a complex 3-dimensional electromagnetic nuclear resonance field on patients with Low Back Pain

The effect of MBST®-NuclearResonanceTherapy with a complex 3-dimensional electromagnetic nuclear resonance field on patients with Low Back Pain

Structural stability of carbon nanotubes using molecular dynamics and finite-difference time-domain methods

The finite-difference time-domain and molecular dynamics method are coupled in both spatial and temporal dimensions to predict mechanical, thermodynamic, electromagnetic properties, and dynamic behaviors of nanoscale materials/devices in complex electromagnetic fields on atomic level. Using the proposed method, impact processes of carbon nanotubes in electromagnetic field are simulated, and the dynamic cracking process is obtained. Finally the structural stability of nanotubes is discussed

Variable step length finite difference method for calculation of the 3-phase electromagnetic field in the long conductor approach

The original motivation of this research is to describe comprehensive solutions based on Finite Difference Method (FDM) together with its software implementation that can handle the infinity long conductor. This paper focuses on developing FDM procedures for solving the interface regions, defined as regions where the step sizes change. Attention has been paid in this problem for creating robust and efficient techniques for solving the complex electromagnetic field at long distance from the transmission line based on a variable step size for the grid of FDM. Reduction in memory requirements has been achieved in these approaches. The industry has identified that there is a pressing need for a comprehensive method together with its software implementation that can handle the infinity long conductor problem. The research results of the project have immediate and practical application to the power industries.

Quantum Field Theory: -- General Relativistic and Ultraviolet Divergence Free. Part II --

This is the second in a series of papers. Here we present a concrete formulation of our new quantum field theories for neutral and complex scalar fields, electromagnetic fields and Dirac fields in vacuo. The cases of QED and QCD shall be considered in a third paper.

Geometrical optics phase matching of radio occultation signals

Remote measurements of the atmospheric state can be performed by radio occultation between satellites, a GPS satellite transmitting a radio signal to a receiving low Earth orbit (LEO) satellite, or between LEO satellites. The bending angle of the traversing optical ray can be measured by detecting the Doppler shift of radio signals. The bending angle is an integrated measure of the refractive index in the atmosphere traversed by the optical ray. With a time series (profile) of the bending angle, it is possible to perform an inversion to obtain the refractive index. Various techniques for the retrieval of the bending profile already exist. The most recent methods have solved the problem of multipath, i.e., when the atmosphere allows several rays to exist simultaneously. The paper presents a new method for the reconstruction of bending angle as a single‐valued function of impact parameter from complex radio occultation signal under multipath propagation conditions. The method utilizes the assumption of spherical symmetry of refractivity, i.e., n() = n(r), and the principle of synthetic aperture, thus allowing sub‐Fresnel resolution. A distinctive feature of the method, as compared to previously known methods, is direct applicability for arbitrary orbits of transmitting and receiving satellites, without intermediate propagation of complex electromagnetic field to circle or straight line. This comes at the expense of impossibility to reduce the method to a FFT. The method can be useful for inverting radio occultation signals and for validation of other radio holographic methods.

Electric/magnetic reciprocity in premetric electrodynamics with and without magnetic charge, and the complex electromagnetic field

We extend an axiomatic approach to classical electrodynamics, which we developed recently, to the case of nonvanishing magnetic charge. Then two axioms, namely those of the existence of the Lorentz force (Axiom 2) and of magnetic flux conservation (Axiom 3) have to be generalized. Electric/magnetic reciprocity constitutes a guiding principle for this undertaking. The extension of the axioms can be implemented at a premetric stage, i.e., when metric and connection of spacetime do not play a role. Complex Riemann–Silberstein fields of the form ( E±i H , D±iB ) have a natural place in the theory, independent of the Hodge duality mapping defined by any particular metric.

Semi-analytical electromagnetic field computation

Any of the numerical methods for electromagnetic field analysis essentially require a subdivision of a problem region. By notifying this subdivision, we have previously proposed a new methodology by applying the analytical solution to each of the discretized parts. The first trial of this semi-analytical electromagnetic filed computational methodology has made it possible to simulate the complex electromagnetic field distributions not obtainable by the conventional numerical schemes, such as finite and boundary elements means. However, our semi-analytical method encounters some difficulty when analyzing the high frequency electromagnetic field distributions because of the displacement currents.In the present paper, we propose a new semi-analytical approach taking the displacement currents into account to overcome this difficulty.

Detection of high‐altitude ionospheric irregularities with GPS/MET

In this study radio occultation data from the GPS/MET experiment are used for detection of high‐altitude ionospheric irregularities. This is done by back propagation of the complex electromagnetic field observed in orbit while accounting for the direction of the Earth's magnetic field. The irregularities are detected mainly in the F region. However, for some occultations they are detected above the F2 peak at altitudes up to 1000 km and higher. Results of numerical simulations, a description of the used algorithm, and examples of the processed GPS/MET data are presented.

Subsurface Microwave Imaging By Using Angular Spectrum of Electromagnetic Field

The new approach to the solution of a problem of the microwave image reconstruction of the subsurface objects is offered in the present work. Necessity of the complex amplitude measurement of electromagnetic field is excluded in a point on a direct line above surface in the considered further method. Calculation of the direct Fourier transformation of the measured field is also excluded. In the experiment, data on complex electromagnetic field (data of the transmission coefficients) at 32 frequencies in the operating band with a constant frequency step was used. Experiments were carried out at frequencies from 3 to 4 GHz. The images of the irradiating dipoles, considered as models of the scattering centers of an object, were reconstructed from the measured data.

変位電流の可視化法とウェーブレット変換による特徴抽出

Previously, we have proposed a semi-analytical electromagnetic filed computation method, which has made it possible to compute the complex electromagnetic field distributions not obtainable by the conventional numerical schemes, such as finite elements and boundary elements means. However, because of the displacement current, our semi-analytical method encounters some difficulty when analyzing the high frequency electromagnetic field distribution. To overcome this difficulty, we are now developing a new semi-analytical approach taking the displacement currents into account. In the present paper, we visualize the displacement currents by new-semi-analytical method, and its spatial distributing characteristics are extracted by means of wavelets analysis.

331ウェーブレット変換を用いた電気回路網の近似解析

Previously, we have proposed a quasi-analytical electromagnetic filed computation methodology, which has made it possible to compute the complex electromagnetic field distributions not obtainable by the conventional numerical schemes, such as finite elements and boundary elements means. However, because of the displacement current, our quasi-analytical method encounters a some difficulty when analyzing the high frequency electromagnetic field distribution. To overcome this difficulty, we are now developing a new quasi-analytical approach taking the displacement currents into account. In the present paper, in order to reduce a computational load of our method and to obtain a good approximate solution, we apply the wavelet transform method to our system of equations. As a result, it is found that the wavelet transform method yields a good solution when exciting by the relatively low frequencies.

A methodology for two-dimensional finite element analysis of electromagnetically driven flow in induction stirring systems

This paper describes an integral closure approach for the 2-D analysis of electromagnetically driven flow in inductively coupled molten metal using the finite element method. This methodology, which restricts the solution domain to the conducting regions(s), was demonstrated for flows generated by complex electromagnetic fields, and computed results were found to be in good agreement with measurements.

An artificial intelligence system for a complex electromagnetic field problem. I. Finite element calculations and fuzzy logic development

Artificial intelligence (AI) has been used to determine the electromagnetic field in the complex problem of a faulty overhead transmission line above earth and a buried pipeline. A suitable AI system for scaling finite element electromagnetic field calculations has been developed. This system was trained by using finite element calculations for configurations, i.e., cases having different distances between the overhead transmission line and the buried pipeline as well as different earth resistivities. The AI system may be used to calculate the electromagnetic field in new cases differing significantly from the cases used for training.

An artificial intelligence system for a complex electromagnetic field problem. II. Method implementation and performance analysis

For pt. I see ibid., vol. 35, no. 1, p. 516-22 (1999). An artificial intelligence system has been developed to determine the electromagnetic field in the complex problem of a faulty overhead transmission line above earth and a buried pipeline. The amplitude and phase of the magnetic vector potential (MVP) in the earth around the pipeline neighborhood, including the pipeline itself, are calculated, The performance of the trained fuzzy logic system (FLS) described in Part I was tested extensively for various configurations of the above electromagnetic field problem, differing significantly from the cases used for training. The trained FLS parameters required to calculate the electromagnetic field by simple formulas are also presented.

Time-domain Green dyadics for temporally dispersive, bi-isotropic media

Time-domain Green dyadics for linear, homogeneous, temporally dispersive bi-isotropic media are presented. A complex time-dependent electromagnetic field is introduced. Approximation to the complex field from an electric point dipole in an unbounded bi-isotropic medium with respect to the slowly varying components (second forerunner approximation) is obtained. Numerical examples are presented. Surface integral equations for the tangential components of the electromagnetic fields are derived for two standard scattering problems.