Science Publishing Group: American Journal of Electromagnetics and Applications: Table of Contents
<i> American Journal of Electromagnetics and Applications (AJEA) </i> provides a forum for sharing timely and up-to-date publication of scientific research and review articles. The journal publishes original full-length research papers in all areas related to electromagnetics and its applications. It aims to contribute to intersciences coupling applied electromagnetics, mechanics and materials.The following categories are accepted: Original researches, case reports, reviews, technology papers and brief communications.
http://www.sciencepublishinggroup.com/j/ajea Science Publishing Group: American Journal of Electromagnetics and Applications: Table of Contents
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American Journal of Electromagnetics and Applications
American Journal of Electromagnetics and Applications
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Diffraction of a Plane Inhomogeneous Electromagnetic Wave by a Perfectly Conducting Half-Plane in an Absorbing Medium
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The Sommerfeld’s problem of plane wave diffraction by a perfectly conducting half-plane is considered for the general case of an absorbing medium and an inhomogeneous incident wave, whose the constant phase planes are not parallel to the constant amplitude ones. The exact solution is represented in terms of parameters of incident wave propagation in the coordinate axes, but not in terms of angular variables, as usually. We adduce the original derivation of this solution, which use generalized functions and admits complex values for propagation parameters. Our approach is based on calculation of diffraction integrals by the method of transformations on the real axis without using a complex argument of integration. The results of diffraction field computation for the cases of an absorbing medium and of a decaying incident wave in a transparent medium are presented.
The Sommerfeld’s problem of plane wave diffraction by a perfectly conducting half-plane is considered for the general case of an absorbing medium and an inhomogeneous incident wave, whose the constant phase planes are not parallel to the constant amplitude ones. The exact solution is represented in terms of parameters of incident wave propagation in the coordinate axes, but not in terms of angular variables, as usually. We adduce the original derivation of this solution, which use generalized functions and admits complex values for propagation parameters. Our approach is based on calculation of diffraction integrals by the method of transformations on the real axis without using a complex argument of integration. The results of diffraction field computation for the cases of an absorbing medium and of a decaying incident wave in a transparent medium are presented.
Diffraction of a Plane Inhomogeneous Electromagnetic Wave by a Perfectly Conducting Half-Plane in an Absorbing Medium
doi:10.11648/j.ajea.20130101.11
American Journal of Electromagnetics and Applications
2014-01-01
© Science Publishing Group
Vladimir M. Serdyuk
Joseph A. Titovitsky
Diffraction of a Plane Inhomogeneous Electromagnetic Wave by a Perfectly Conducting Half-Plane in an Absorbing Medium
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Elliptical Antenna Array Pattern Synthesis with Fixed Side Lobe Level and Suitable Main Lobe Beam width by Genetic Algorithm
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In this paper, the design of uniform elliptical array (UEA) with optimum side lobe level reduction is presented. Multi-lobe pattern and adaptive nulling of the pattern is achieved by the control of the antenna elements phases in different states. This method is based on genetic algorithm (GA). The method of genetic algorithm is used to determine an optimum set of array factor cost that provide a radiation pattern with maximum side lobe level reduction with constraint of a suitable main lobe beamwidth. The results show that synthesis of the uniform elliptical antenna array by using GA method provide a side lobe level reduction and main lobe beamwidth better than circular antenna array obtained by using IWO (Invasive Weeds Optimization) and also optimized elliptical antenna array by using EPL (The Excitations Of Elements Phases at Eccentricity Low Level).
In this paper, the design of uniform elliptical array (UEA) with optimum side lobe level reduction is presented. Multi-lobe pattern and adaptive nulling of the pattern is achieved by the control of the antenna elements phases in different states. This method is based on genetic algorithm (GA). The method of genetic algorithm is used to determine an optimum set of array factor cost that provide a radiation pattern with maximum side lobe level reduction with constraint of a suitable main lobe beamwidth. The results show that synthesis of the uniform elliptical antenna array by using GA method provide a side lobe level reduction and main lobe beamwidth better than circular antenna array obtained by using IWO (Invasive Weeds Optimization) and also optimized elliptical antenna array by using EPL (The Excitations Of Elements Phases at Eccentricity Low Level).
Elliptical Antenna Array Pattern Synthesis with Fixed Side Lobe Level and Suitable Main Lobe Beam width by Genetic Algorithm
doi:10.11648/j.ajea.20130101.12
American Journal of Electromagnetics and Applications
2014-01-01
© Science Publishing Group
Amir SamanZare
Elliptical Antenna Array Pattern Synthesis with Fixed Side Lobe Level and Suitable Main Lobe Beam width by Genetic Algorithm
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© Science Publishing Group
Simulation of the S-Band Photon Vorticity Modulation Scheme
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Electromagnetic (EM) vorticity modulation is a multi-carrier scheme that offers an enhanced spectral efficiency among the several conventional communication technologies. A mathematical model of the beam-front, carrying different orbital angular momentum (OAM) states, in the S-Band region of the radio frequency (RF) spectrum has been presented using the Laguerre-Gaussian (LG) beam, to describe the effect of RF vorticity and OAM modulation. Results from EM simulations are used to verify the orthogonality of OAM states and thereby highlighting its application in a multi-user environment. Two designs of antenna reflectors are being proposed to generate the orthogonal OAM states (l=1 and 2). The existence of the OAM states is visualized from the distribution of the current densities and magnetic fields over the aperture area of the reflectors.
Electromagnetic (EM) vorticity modulation is a multi-carrier scheme that offers an enhanced spectral efficiency among the several conventional communication technologies. A mathematical model of the beam-front, carrying different orbital angular momentum (OAM) states, in the S-Band region of the radio frequency (RF) spectrum has been presented using the Laguerre-Gaussian (LG) beam, to describe the effect of RF vorticity and OAM modulation. Results from EM simulations are used to verify the orthogonality of OAM states and thereby highlighting its application in a multi-user environment. Two designs of antenna reflectors are being proposed to generate the orthogonal OAM states (l=1 and 2). The existence of the OAM states is visualized from the distribution of the current densities and magnetic fields over the aperture area of the reflectors.
Simulation of the S-Band Photon Vorticity Modulation Scheme
doi:10.11648/j.ajea.20130102.13
American Journal of Electromagnetics and Applications
2014-01-01
© Science Publishing Group
Abhay SA
Pavaneeswar BR
Gopinath S
Sriram BS
Thomas SJ
Shanmugha Sundaram GA
Simulation of the S-Band Photon Vorticity Modulation Scheme
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http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20130102.13
© Science Publishing Group
Approximate Electromagnetic Cloaking of Spherical Bodies Using Nonlinear Transformation with Improved Total Scattering
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Cloaking refers to hiding a body from detection by surrounding it with a coating consisting of an unusual anisotropic nonhomogeneous material. The permittivity and permeability of such a cloak are determined by the coordinate transformation of compressing a hidden body into a point or a line. In this work, the scattering properties of cloaked spherical bodies (conducting and dielectric) are investigated using a combination of approximate cloaking, where the conducting sphere is transformed into a small sphere rather than to a point, and using two types of nonlinear transformations; concave-up and concave-down. The radially-dependent spherical cloaking shell is approximately discretized into many homogeneous anisotropic layers, provided that the thickness of each layer is much less than the wavelength, and this discretization raises the level of scattering as the number of layers decreases. Each anisotropic layer can be replaced by a pair of equivalent isotropic sub-layers, where the effective medium approximation is used to find the parameters of these two equivalent sub-layers. The effect of nonlinearity in the coordinate transformation on the scattering performance is studied. The back-scattering normalized radar cross section, the scattering pattern are studied and the total scattering cross section against the frequency for different number of layers and transformed radius.
Cloaking refers to hiding a body from detection by surrounding it with a coating consisting of an unusual anisotropic nonhomogeneous material. The permittivity and permeability of such a cloak are determined by the coordinate transformation of compressing a hidden body into a point or a line. In this work, the scattering properties of cloaked spherical bodies (conducting and dielectric) are investigated using a combination of approximate cloaking, where the conducting sphere is transformed into a small sphere rather than to a point, and using two types of nonlinear transformations; concave-up and concave-down. The radially-dependent spherical cloaking shell is approximately discretized into many homogeneous anisotropic layers, provided that the thickness of each layer is much less than the wavelength, and this discretization raises the level of scattering as the number of layers decreases. Each anisotropic layer can be replaced by a pair of equivalent isotropic sub-layers, where the effective medium approximation is used to find the parameters of these two equivalent sub-layers. The effect of nonlinearity in the coordinate transformation on the scattering performance is studied. The back-scattering normalized radar cross section, the scattering pattern are studied and the total scattering cross section against the frequency for different number of layers and transformed radius.
Approximate Electromagnetic Cloaking of Spherical Bodies Using Nonlinear Transformation with Improved Total Scattering
doi:10.11648/j.ajea.20130102.11
American Journal of Electromagnetics and Applications
2014-01-01
© Science Publishing Group
Hany M. Zamel
Essam El Diwany
Hadia El Hennawy
Approximate Electromagnetic Cloaking of Spherical Bodies Using Nonlinear Transformation with Improved Total Scattering
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© Science Publishing Group
The Behavior of MFIE and EFIE at Interior Resonances and Its Impact in MOT Late Time Stability
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In the vicinity of a certain interior frequency, the current density on the surface of a perfect electric conducting scatterer, when illuminated by an incident field, is divided into two parts: an induced surface current caused by the incident field and a resonance surface current associated with the interior resonance mode. Equivalent RLC circuit models are proposed respectively for PEC scatterers associated with the electric field integral equation (EFIE) and the magnetic field integral equation (MFIE). Using the circuit models, together with the power conservation law, the different behavior of the resonance surface currents associated with EFIE and MFIE is analyzed and checked with numerical examples in two-dimensional space. It is shown that the interior resonance behavior has significant influence on the late time stability associated with time domain EFIE and MFIE.
In the vicinity of a certain interior frequency, the current density on the surface of a perfect electric conducting scatterer, when illuminated by an incident field, is divided into two parts: an induced surface current caused by the incident field and a resonance surface current associated with the interior resonance mode. Equivalent RLC circuit models are proposed respectively for PEC scatterers associated with the electric field integral equation (EFIE) and the magnetic field integral equation (MFIE). Using the circuit models, together with the power conservation law, the different behavior of the resonance surface currents associated with EFIE and MFIE is analyzed and checked with numerical examples in two-dimensional space. It is shown that the interior resonance behavior has significant influence on the late time stability associated with time domain EFIE and MFIE.
The Behavior of MFIE and EFIE at Interior Resonances and Its Impact in MOT Late Time Stability
doi:10.11648/j.ajea.20130102.12
American Journal of Electromagnetics and Applications
2014-01-01
© Science Publishing Group
Lianrong Hong
Guiyu Tian
Jinpeng Fang
Gaobiao Xiao
The Behavior of MFIE and EFIE at Interior Resonances and Its Impact in MOT Late Time Stability
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© Science Publishing Group
Electromagnetic Scattering by Approximately Cloaked Cylindrical Bodies Using Homogeneous Isotropic Multi-Layered Materials
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In cloaking, a body is hidden from detection by surrounding it by a coating consisting of an unusual anisotropic nonhomogeneous material. Its function is to deflect the rays that would have struck the object, guide them around the object, and return them to their original trajectory, thus no waves are scattered from the body. The permittivity and permeability of such a cloak are determined by the coordinate transformation of compressing a hidden body into a point or a line.Some components of the electrical parameters of the cloaking material(ε,μ) are required to have infinite or zero value at the boundary of the hidden object. Approximate cloaking can be achieved by transforming the cylindrical body (dielectric and conducting) virtually into a small cylinder rather than a line, which eliminates the zero or infinite values of the electrical parameters. The radially-dependent cylindrical cloaking shell can be approximately discretized into many homogeneous anisotropic layers; each anisotropic layer can be replaced by a pair of equivalent isotropic sub-layers, where the effective medium approximation is used to find the parameters of these two equivalent sub-layers. In this work, the scattering properties of cloaked cylindrical bodies (dielectric and conducting) are investigated using a combination of approximate cloaking, together with discretizing the cloaking material using pairs of homogeneous isotropic sub-layers. The solution is obtained by rigorously solving Maxwell equations using angular harmonics expansion. The scattering pattern, and the back scattering cross section against the frequency are studied for both transverse magnetic (TMz) and transverse electric (TEz) polarizations of the incident plane wave for different transformed body radii.
In cloaking, a body is hidden from detection by surrounding it by a coating consisting of an unusual anisotropic nonhomogeneous material. Its function is to deflect the rays that would have struck the object, guide them around the object, and return them to their original trajectory, thus no waves are scattered from the body. The permittivity and permeability of such a cloak are determined by the coordinate transformation of compressing a hidden body into a point or a line.Some components of the electrical parameters of the cloaking material(ε,μ) are required to have infinite or zero value at the boundary of the hidden object. Approximate cloaking can be achieved by transforming the cylindrical body (dielectric and conducting) virtually into a small cylinder rather than a line, which eliminates the zero or infinite values of the electrical parameters. The radially-dependent cylindrical cloaking shell can be approximately discretized into many homogeneous anisotropic layers; each anisotropic layer can be replaced by a pair of equivalent isotropic sub-layers, where the effective medium approximation is used to find the parameters of these two equivalent sub-layers. In this work, the scattering properties of cloaked cylindrical bodies (dielectric and conducting) are investigated using a combination of approximate cloaking, together with discretizing the cloaking material using pairs of homogeneous isotropic sub-layers. The solution is obtained by rigorously solving Maxwell equations using angular harmonics expansion. The scattering pattern, and the back scattering cross section against the frequency are studied for both transverse magnetic (TMz) and transverse electric (TEz) polarizations of the incident plane wave for different transformed body radii.
Electromagnetic Scattering by Approximately Cloaked Cylindrical Bodies Using Homogeneous Isotropic Multi-Layered Materials
doi:10.11648/j.ajea.20130103.11
American Journal of Electromagnetics and Applications
2014-01-01
© Science Publishing Group
Hany M. Zamel
Essam El Diwany
Hadia El Hennawy
Electromagnetic Scattering by Approximately Cloaked Cylindrical Bodies Using Homogeneous Isotropic Multi-Layered Materials
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2014-01-01
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© Science Publishing Group
A Systematic Analysis and Comparison of the Dispersion Curves of Hypocycloidal and Elliptical Bragg Waveguide Using very Simple Analytical Method
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In this paper we have analyzed the modal dispersion characteristics of two unconventional Bragg waveguides namely hypocycloidal and elliptical Bragg waveguide by the use of very simple matrix method. We are using matrix equation which replaces the boundary condition. We obtained the characteristic equation analytically. In both cases all the outputs are showing in the form of dispersion curves and we are also trying to compare their dispersion characteristics. It is seen that in case of hypocycloidal Bragg waveguide [1] the cut off frequency increases with the decrease of cladding layers .But in case of elliptical Bragg waveguide [2], when the cladding layer decreases from six layered to four layered the cutoff frequency increases and from four layer to two layer the cutoff frequency become decreases.
In this paper we have analyzed the modal dispersion characteristics of two unconventional Bragg waveguides namely hypocycloidal and elliptical Bragg waveguide by the use of very simple matrix method. We are using matrix equation which replaces the boundary condition. We obtained the characteristic equation analytically. In both cases all the outputs are showing in the form of dispersion curves and we are also trying to compare their dispersion characteristics. It is seen that in case of hypocycloidal Bragg waveguide [1] the cut off frequency increases with the decrease of cladding layers .But in case of elliptical Bragg waveguide [2], when the cladding layer decreases from six layered to four layered the cutoff frequency increases and from four layer to two layer the cutoff frequency become decreases.
A Systematic Analysis and Comparison of the Dispersion Curves of Hypocycloidal and Elliptical Bragg Waveguide Using very Simple Analytical Method
doi:10.11648/j.ajea.20140201.11
American Journal of Electromagnetics and Applications
2014-01-01
© Science Publishing Group
Chandra Kamal Borgohain
Chakresh Kumar
A Systematic Analysis and Comparison of the Dispersion Curves of Hypocycloidal and Elliptical Bragg Waveguide Using very Simple Analytical Method
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© Science Publishing Group
Design and Construction of Wireless Power Transfer System Using Magnetic Resonant Coupling
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Wireless power transmission is the transmission of electrical energy without using any conductor or wire. It is useful to transfer electrical energy to those places where it is hard to transmit energy using conventional wires. In this paper, we designed and implemented a wireless power transfer system using the basics of magnetic resonant coupling. Numerical data are presented for power transfer efficiency of both receivers. Graphs are given to show the comparison of power and efficiency with distance of both receivers.
Wireless power transmission is the transmission of electrical energy without using any conductor or wire. It is useful to transfer electrical energy to those places where it is hard to transmit energy using conventional wires. In this paper, we designed and implemented a wireless power transfer system using the basics of magnetic resonant coupling. Numerical data are presented for power transfer efficiency of both receivers. Graphs are given to show the comparison of power and efficiency with distance of both receivers.
Design and Construction of Wireless Power Transfer System Using Magnetic Resonant Coupling
doi:10.11648/j.ajea.20140202.11
American Journal of Electromagnetics and Applications
2014-05-08
© Science Publishing Group
Syed Khalid Rahman
Omar Ahmed
Md. Saiful Islam
A. H. M. Rafiul Awal
Md. Shariful Islam
Design and Construction of Wireless Power Transfer System Using Magnetic Resonant Coupling
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2014-05-08
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http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140202.11
© Science Publishing Group
Scrutiny of Injected Electron Current Polarization Effect on the Threshold Current Density Reduction in QW Spin-Lasers
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One of the mechanisms for threshold current density reduction is using spin polarized carriers generated by electrical spin injection. Electrical spin injection is spin-polarized carrier injection by using a magnetic contact. In this paper, we have solved numerically rate equations governing on semiconductor spin un-polarized and polarized laser with - based quantum well active region in which Schottky tunnel barrier treat as the spin injector. For the first time, we demonstrate simultaneously effect of normalized spin relaxation rate and injected current polarization on threshold current density reduction related to two form of spontaneous recombination. According to our result threshold current density reduction increases by simultaneously normalized spin relaxation rate reduction and increasing of injected current polarization. Maximum obtained threshold current density reduction values for linear and quadratic spontaneous recombination is 0.07 and 0.31. Moreover, we compute and compare the effect of value of injected electron current polarization on normalized spin-filtering interval for two types of recombination. Maximum obtained normalized spin-filtering interval values for linear and quadratic spontaneous recombination is 1.2 and 1.36. Finally we calculate spin-up optical gain and from this we obtained the conditions for achieving optimum optical gain. Maximum obtained spin-up optical gain valueis17.36.
One of the mechanisms for threshold current density reduction is using spin polarized carriers generated by electrical spin injection. Electrical spin injection is spin-polarized carrier injection by using a magnetic contact. In this paper, we have solved numerically rate equations governing on semiconductor spin un-polarized and polarized laser with - based quantum well active region in which Schottky tunnel barrier treat as the spin injector. For the first time, we demonstrate simultaneously effect of normalized spin relaxation rate and injected current polarization on threshold current density reduction related to two form of spontaneous recombination. According to our result threshold current density reduction increases by simultaneously normalized spin relaxation rate reduction and increasing of injected current polarization. Maximum obtained threshold current density reduction values for linear and quadratic spontaneous recombination is 0.07 and 0.31. Moreover, we compute and compare the effect of value of injected electron current polarization on normalized spin-filtering interval for two types of recombination. Maximum obtained normalized spin-filtering interval values for linear and quadratic spontaneous recombination is 1.2 and 1.36. Finally we calculate spin-up optical gain and from this we obtained the conditions for achieving optimum optical gain. Maximum obtained spin-up optical gain valueis17.36.
Scrutiny of Injected Electron Current Polarization Effect on the Threshold Current Density Reduction in QW Spin-Lasers
doi:10.11648/j.ajea.20140202.12
American Journal of Electromagnetics and Applications
2014-05-30
© Science Publishing Group
S. N. Hosseinimotlagh
H. Ghavidelfard
M. Pezeshkian
H. Molaei
Scrutiny of Injected Electron Current Polarization Effect on the Threshold Current Density Reduction in QW Spin-Lasers
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2014-05-30
10.11648/j.ajea.20140202.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140202.12
© Science Publishing Group
Study of Radiation Properties in Taylor Distribution Uniform Spaced Backfire Antenna Arrays
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This paper is the last part in studying the directivity for Linear Long Backfire Antenna arrays, the research will focus on another type of non linear excitation (Taylor )excitation uniform space long backfire antenna array especially the directivity and SLL max (side lobe level maximum )properties of the radiation patterns and plot the relation between the length of the arrays and the directivity. The effect of excitation coefficients values for all elements in the arrays on radiation properties will be studied in all types of non uniform excitation arrays. At last the directivity and SLL for three types of non uniform distribution (Taylor, Chebyshev and Binomial) will be compered .
This paper is the last part in studying the directivity for Linear Long Backfire Antenna arrays, the research will focus on another type of non linear excitation (Taylor )excitation uniform space long backfire antenna array especially the directivity and SLL max (side lobe level maximum )properties of the radiation patterns and plot the relation between the length of the arrays and the directivity. The effect of excitation coefficients values for all elements in the arrays on radiation properties will be studied in all types of non uniform excitation arrays. At last the directivity and SLL for three types of non uniform distribution (Taylor, Chebyshev and Binomial) will be compered .
Study of Radiation Properties in Taylor Distribution Uniform Spaced Backfire Antenna Arrays
doi:10.11648/j.ajea.20140203.11
American Journal of Electromagnetics and Applications
2014-08-17
© Science Publishing Group
Amer Tawfeeq Abed
Study of Radiation Properties in Taylor Distribution Uniform Spaced Backfire Antenna Arrays
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2014-08-17
10.11648/j.ajea.20140203.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140203.11
© Science Publishing Group
New Two Variable Search Algorithm Implemented for Preisach Model
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Preisach model is the most used hysteresis model in magnetic materials research. This article presents problems that appear in implementation of a two variable search algorithm for Preisach model identification. The algorithm is use to find the optimal parameters values for the probability function distribution. The tests for a subway card in the case of longitudinal and transversal magnetization are available.
Preisach model is the most used hysteresis model in magnetic materials research. This article presents problems that appear in implementation of a two variable search algorithm for Preisach model identification. The algorithm is use to find the optimal parameters values for the probability function distribution. The tests for a subway card in the case of longitudinal and transversal magnetization are available.
New Two Variable Search Algorithm Implemented for Preisach Model
doi:10.11648/j.ajea.20140203.12
American Journal of Electromagnetics and Applications
2014-09-05
© Science Publishing Group
Tabara, Octavian Adrian
New Two Variable Search Algorithm Implemented for Preisach Model
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2014-09-05
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http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140203.12
© Science Publishing Group
The Use of Web Simulator as an Auxiliary to the Physical Teaching: Concepts about Electromagnetism in the Distance Education Mode
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140204.11
The world is changing constantly and together with it education and its modalities, that is, the dimension that education develops it becomes necessary to comply with the new demands emerging from this development. The distance education is one of these developments in education system, with all the specifics, it's more than that, it is a window of opportunity that opens, allowing the population to achieve satisfactory educational levels, especially in a country of continental dimensions as Brazil. Ahead of this scene, it is observed a moment where the development of the Technologies of Information and Communication (ICT) never reached waited levels, proving the importance of distance education in our country. In this work, the contributions of ICT involved in teaching through the Web are presented, regarding particularly the use of virtual simulators in electromagnetism bases. The technological easinesses proportionated by the TIC enter in this modality of education as one of the main technologies directed to education in the distance and virtual simulation as one among some effective methodological tools in this education. The simulators are programs that simulate the behavior of physical systems from predetermined models. Simulation results are usually presented in large format visual appeal, as animations, graphs. Thus, little intuitive concepts and of difficult visualization as the concepts on Electromagnetism, become accessible the students. Currently, simulation programs are probably the most popular application way of computers to Physics teaching. A range of these programs is available on the Web in apllets’s form written in Java®, Flash® among others. In this paper, the electromagnetic simulations had limited to the use of on-line virtual platform available at htpps://phet.colorado.edu/pt_BR, in this interactive website, it’s possible to select not only electromagnetism simulations, as well as in other Physics’ areas offering to the students an extremely interactive environment of significant learning.
The world is changing constantly and together with it education and its modalities, that is, the dimension that education develops it becomes necessary to comply with the new demands emerging from this development. The distance education is one of these developments in education system, with all the specifics, it's more than that, it is a window of opportunity that opens, allowing the population to achieve satisfactory educational levels, especially in a country of continental dimensions as Brazil. Ahead of this scene, it is observed a moment where the development of the Technologies of Information and Communication (ICT) never reached waited levels, proving the importance of distance education in our country. In this work, the contributions of ICT involved in teaching through the Web are presented, regarding particularly the use of virtual simulators in electromagnetism bases. The technological easinesses proportionated by the TIC enter in this modality of education as one of the main technologies directed to education in the distance and virtual simulation as one among some effective methodological tools in this education. The simulators are programs that simulate the behavior of physical systems from predetermined models. Simulation results are usually presented in large format visual appeal, as animations, graphs. Thus, little intuitive concepts and of difficult visualization as the concepts on Electromagnetism, become accessible the students. Currently, simulation programs are probably the most popular application way of computers to Physics teaching. A range of these programs is available on the Web in apllets’s form written in Java®, Flash® among others. In this paper, the electromagnetic simulations had limited to the use of on-line virtual platform available at htpps://phet.colorado.edu/pt_BR, in this interactive website, it’s possible to select not only electromagnetism simulations, as well as in other Physics’ areas offering to the students an extremely interactive environment of significant learning.
The Use of Web Simulator as an Auxiliary to the Physical Teaching: Concepts about Electromagnetism in the Distance Education Mode
doi:10.11648/j.ajea.20140204.11
American Journal of Electromagnetics and Applications
2014-11-22
© Science Publishing Group
Cairo Dias Barbosa
José Gidauto Dos Santos Lima Junior
Juliano Cordeiro Gallottes
Luiz Moreira Gomes
Fernanda Carla Lima Ferreira
The Use of Web Simulator as an Auxiliary to the Physical Teaching: Concepts about Electromagnetism in the Distance Education Mode
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2014-11-22
2014-11-22
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http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140204.11
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The Hidden Quantum Entanglement Roots of E = mc2 and Its Genesis to E = (mc2/22) Plus mc2 (21/22) Confirming Einstein’s Mass-Energy Formula
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140205.11
Einstein’s energy mass formula is shown to consist of two basically quantum components E (O) = mc2/22 and E(D) = mc2(21/22). We give various arguments and derivations to expose the quantum entanglement physics residing inside a deceptively simple expression E = mc2. The true surprising aspect of the present work is however the realization that all the involved ‘physics’ in deriving the new quantum dissection of Einstein’s famous formula of special relativity is actually a pure mathematical necessity anchored in the phenomena of volume concentration of convex manifold in high dimensional quasi Banach spaces. Thus the present derivation plus the measurements of accelerated cosmic expansion are endophysical theoretical and experimental confirmation of Einstein but with a new quantum relativistic interpretation.
Einstein’s energy mass formula is shown to consist of two basically quantum components E (O) = mc2/22 and E(D) = mc2(21/22). We give various arguments and derivations to expose the quantum entanglement physics residing inside a deceptively simple expression E = mc2. The true surprising aspect of the present work is however the realization that all the involved ‘physics’ in deriving the new quantum dissection of Einstein’s famous formula of special relativity is actually a pure mathematical necessity anchored in the phenomena of volume concentration of convex manifold in high dimensional quasi Banach spaces. Thus the present derivation plus the measurements of accelerated cosmic expansion are endophysical theoretical and experimental confirmation of Einstein but with a new quantum relativistic interpretation.
The Hidden Quantum Entanglement Roots of E = mc2 and Its Genesis to E = (mc2/22) Plus mc2 (21/22) Confirming Einstein’s Mass-Energy Formula
doi:10.11648/j.ajea.20140205.11
American Journal of Electromagnetics and Applications
2014-12-22
© Science Publishing Group
Mohamed S. El Naschie
The Hidden Quantum Entanglement Roots of E = mc2 and Its Genesis to E = (mc2/22) Plus mc2 (21/22) Confirming Einstein’s Mass-Energy Formula
2
5
44
44
2014-12-22
2014-12-22
10.11648/j.ajea.20140205.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140205.11
© Science Publishing Group
Effect of Microwave Field on the Emergence of the Electromotive Force in Asymmetrical P-N-Junction
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140205.12
In asymmetric p-n-junction in a strong microwave field for the analysis of voltage and current necessary to consider both the heating of electrons and holes. total current and voltage generated is determined not by the temperature of the hot electrons and the temperature of the carriers that are decisive. three-dimensional image on the surface f(jsc,Te Th,) and f (Uoc Te Th) to determine the possible range of the voltages and currents generated by the p-n-junction in a strong microwave field.
In asymmetric p-n-junction in a strong microwave field for the analysis of voltage and current necessary to consider both the heating of electrons and holes. total current and voltage generated is determined not by the temperature of the hot electrons and the temperature of the carriers that are decisive. three-dimensional image on the surface f(jsc,Te Th,) and f (Uoc Te Th) to determine the possible range of the voltages and currents generated by the p-n-junction in a strong microwave field.
Effect of Microwave Field on the Emergence of the Electromotive Force in Asymmetrical P-N-Junction
doi:10.11648/j.ajea.20140205.12
American Journal of Electromagnetics and Applications
2014-12-26
© Science Publishing Group
Muhammadjon Gulomkodirovich Dadamirzaev
Effect of Microwave Field on the Emergence of the Electromotive Force in Asymmetrical P-N-Junction
2
5
48
48
2014-12-26
2014-12-26
10.11648/j.ajea.20140205.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140205.12
© Science Publishing Group
Use of Artificial Dielectric for Improvement of Printed Biconical Vibrator Matching
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140206.11
This article shows that use of artificial dielectric in form of two-dimensional array consisted of small plates can transform electrical input impedance of printed biconical vibrator in ultra-wide bandwidth and improve quality of its matching. It is also found that use of this artificial dielectric eliminates deep dip in radiation pattern of planar biconical vibrator in direction normal of its plane at high frequencys.
This article shows that use of artificial dielectric in form of two-dimensional array consisted of small plates can transform electrical input impedance of printed biconical vibrator in ultra-wide bandwidth and improve quality of its matching. It is also found that use of this artificial dielectric eliminates deep dip in radiation pattern of planar biconical vibrator in direction normal of its plane at high frequencys.
Use of Artificial Dielectric for Improvement of Printed Biconical Vibrator Matching
doi:10.11648/j.ajea.20140206.11
American Journal of Electromagnetics and Applications
2015-02-02
© Science Publishing Group
A. S. Avdushin
A. V. Ashikhmin
Yu. G. Pasternak
S. M. Fedorov
Use of Artificial Dielectric for Improvement of Printed Biconical Vibrator Matching
2
6
52
52
2015-02-02
2015-02-02
10.11648/j.ajea.20140206.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20140206.11
© Science Publishing Group
Virtual Antenna Array Theory and Applications
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20150301.11
In this article we would like to present a physical basis of virtual antenna array method which is based on electrodynamic principle of field source equivalence. Also, here are formulae and numerical relations for field description errors for the field at the edges of physical and virtual antenna arrays It is also demonstrated that the virtual antenna array method helps increase radio emitters angular coordinates accuracy even without data about antenna array carrier body geometry and material properties. Potential use of this method is also provided.
In this article we would like to present a physical basis of virtual antenna array method which is based on electrodynamic principle of field source equivalence. Also, here are formulae and numerical relations for field description errors for the field at the edges of physical and virtual antenna arrays It is also demonstrated that the virtual antenna array method helps increase radio emitters angular coordinates accuracy even without data about antenna array carrier body geometry and material properties. Potential use of this method is also provided.
Virtual Antenna Array Theory and Applications
doi:10.11648/j.ajea.20150301.11
American Journal of Electromagnetics and Applications
2015-02-02
© Science Publishing Group
A. V. Ashikhmin
Yu. G. Pasternak
Yu. A. Rembovskiy
S. M. Fedorov
Virtual Antenna Array Theory and Applications
3
1
11
11
2015-02-02
2015-02-02
10.11648/j.ajea.20150301.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20150301.11
© Science Publishing Group
Design of an All Optical 3-Bit Modulo Eight Asynchronous Up Counter
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20150302.11
The paper presents an all-optical 3 bit up counter with complete Boolean functionality as a representative circuit for modeling and optimization of monolithically integrated components. Here, the proposed logic unit design is based on nonlinear effects in semiconductor optical amplifiers (SOA).These equations are first solved to generate the pump, probe and conjugate pulses in a SOA. The pulse behavior are analyzed and applied to realize behavior of all-optical NAND gate. Next, the logic is used to implement All-Optical D Flip-Flop logic, and its function is verified with the help of truth table. Finally with the help of three D Flip-Flops, a 3-bit up counter is proposed.
The paper presents an all-optical 3 bit up counter with complete Boolean functionality as a representative circuit for modeling and optimization of monolithically integrated components. Here, the proposed logic unit design is based on nonlinear effects in semiconductor optical amplifiers (SOA).These equations are first solved to generate the pump, probe and conjugate pulses in a SOA. The pulse behavior are analyzed and applied to realize behavior of all-optical NAND gate. Next, the logic is used to implement All-Optical D Flip-Flop logic, and its function is verified with the help of truth table. Finally with the help of three D Flip-Flops, a 3-bit up counter is proposed.
Design of an All Optical 3-Bit Modulo Eight Asynchronous Up Counter
doi:10.11648/j.ajea.20150302.11
American Journal of Electromagnetics and Applications
2015-06-19
© Science Publishing Group
Chandra Kamal Borgohain
Chakresh Kumar
Satyajit Bora
Design of an All Optical 3-Bit Modulo Eight Asynchronous Up Counter
3
2
15
15
2015-06-19
2015-06-19
10.11648/j.ajea.20150302.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20150302.11
© Science Publishing Group
Single and Multiband UWB Circular Patch Antenna for Wireless Communication Applications
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20150303.11
This paper presents the design of an ultra-wide band (UWB) circular patch antenna with microstrip line feed and optimization of various antenna parameters. The antenna with dimension of (33 x 30 x 1.5) mm<sup>3</sup> is fabricated on FR-4 epoxy substrate having permittivity constant ε<sub>r</sub>=4.3, loss tangent tanδ=0.002. The designed antenna has the capability of operating in the bands (2.7-4) GHz, (6.8-12.5) GHz and (14.6-18) GHz. The antenna performance was modified by inserting a slot in the ground plane to achieve impedance bandwidth (S11<-10dB) in (2.7-20) GHz. The modified antenna was fabricated and tested using the vector network analyzer. The simulated and measured results are presented and compared. The feed line used has characteristic impedance of 50Ω.
This paper presents the design of an ultra-wide band (UWB) circular patch antenna with microstrip line feed and optimization of various antenna parameters. The antenna with dimension of (33 x 30 x 1.5) mm<sup>3</sup> is fabricated on FR-4 epoxy substrate having permittivity constant ε<sub>r</sub>=4.3, loss tangent tanδ=0.002. The designed antenna has the capability of operating in the bands (2.7-4) GHz, (6.8-12.5) GHz and (14.6-18) GHz. The antenna performance was modified by inserting a slot in the ground plane to achieve impedance bandwidth (S11<-10dB) in (2.7-20) GHz. The modified antenna was fabricated and tested using the vector network analyzer. The simulated and measured results are presented and compared. The feed line used has characteristic impedance of 50Ω.
Single and Multiband UWB Circular Patch Antenna for Wireless Communication Applications
doi:10.11648/j.ajea.20150303.11
American Journal of Electromagnetics and Applications
2015-09-07
© Science Publishing Group
Raad H. Thaher
Single and Multiband UWB Circular Patch Antenna for Wireless Communication Applications
3
3
23
23
2015-09-07
2015-09-07
10.11648/j.ajea.20150303.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=225&doi=10.11648/j.ajea.20150303.11
© Science Publishing Group