International Journal of Applied Electromagnetics and Mechanics - Volume 19, issue 1-4

Authors: Oliveri, Maria E. | Coco, Salvatore | Gazzo, Daniela S.M. | Giuffrida, Cinzia | Laudani, Antonino

Article Type: Research Article

Abstract: A 3D stationary Langevin-Lorentz-Poisson (LLP) coupled model is presented to investigate the ion transport across excitable cell membranes in the presence of external ELF magnetic field. The strategy proposed is based on an iterative scheme which alternates the solution of a Poisson problem with the time-domain integration of the Langevin-Lorentz equation. A Fokker-Planck analysis of the latter equation is perfomed to compute the statistical parameters of ion motion. This approach has been especially set up in …order to take into account explicitly the ion-ion interaction inside ionic channels which has not been considered in literature. The simulations performed show that ELF magnetic field of low intensity (100 μT) can effect significantly the dynamical parameters of ion motion inside the channel provided that the ion-ion interaction is considered. Show more

Keywords: Langevin-Lorentz equation, ion transport, ionic channel

DOI: 10.3233/JAE-2004-555

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 165-168, 2004

Authors: Sudo, Seiichi | Ise, Kazutaka

Article Type: Research Article

Abstract: This paper is concerned with the development of the vibration system for the drop formation of magnetic fluid. The breakup of magnetic fluid jet generated by the longitudinal vibration of the permanent magnet-magnetic fluid system is studied experimentally with the three-dimensional motion analysis system. The detailed processes of the droplet production, capillary jet breakup, and jet formation are revealed.

Keywords: magnetic fluid, magnetohydrodynamics, drop, jet, magnetic field

DOI: 10.3233/JAE-2004-556

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 169-174, 2004

Authors: Grechishkin, R.M. | Koledov, V.V. | Shavrov, V.G. | Dikshtein, I.E. | Khovailo, V.V. | Takagi, T. | Buchelnikov, V.D. | Taskaev, S.V.

Article Type: Research Article

Abstract: The martensitic twin and magnetic domain structures of polycrystalline samples of the shape memory Ni_{2+x} Mn_{1-x} Ga alloys are studied by magnetooptic and Bitter colloid techniques. It is shown, that the analysis of the magnetic domain structure allows one to determine the martensitic structure characteristics, such as symmetry of phases and tetragonal axes orientation. A theoretical model is in good agreement with the experiment.

DOI: 10.3233/JAE-557-XXX

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 175-178, 2004

Authors: Ionita, Anca Daniela | Ionita, Valentin

Article Type: Research Article

Abstract: Biomedical measurements are disturbed by electromagnetic noise that may be modelled as a sum of components with symmetrical distribution of frequencies. Therefore, theoretically, a method working in the high order spectra domain eliminates this noise; practically, simulations prove that it can significantly improve the signal to noise ratio. The paper contains a study for cleaning electromyographic and electroneurographic signals covered by Gaussian noise and periodic electromagnetic interference with low frequencies.

Keywords: biomedical signals, electromagnetic noise, high order spectra

DOI: 10.3233/JAE-2004-558

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 179-182, 2004

Authors: Merckel, Olivier | Fleury, Gilles

Article Type: Research Article

Abstract: Specific Absorption Rate (SAR) designates the electromagnetic power density deposited per unit mass of biological tissues. This paper presents a new approach where SAR calculation for mobile phones is based on a parametric reconstruction of the E-field distribution in the phantom to assess rapid SAR measurements, by means of an ellipsoidal model. The estimation of its parameters is achieved by two ways: using a reduced number of real data points exclusively, and using a combination of …real data points and E-field extrapolation with a given expansion model. Show more

Keywords: SAR, parametric, fast

DOI: 10.3233/JAE-2004-559

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 183-186, 2004

Authors: Benabou, Abdelkader | Clénet, Stéphane | Piriou, Francis

Article Type: Research Article

Abstract: In this communication, we propose a dynamical model of hysteresis giving the magnetization M in function of the flux density B. The mathematical development is based on the Jiles approach for frequency dependent hysteresis. The obtained model is simple to carry out and fast. The model is tested through a comparison with experimental results on FeSi steel sheets. Then, the accuracy and the range of application of the model are discussed.

Keywords: eddy current, dynamical hysteresis, Jiles-Atherton model

DOI: 10.3233/JAE-2004-560

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 187-191, 2004

Authors: Schreiber, Ute | Clemens, Markus | van Rienen, Ursula

Article Type: Research Article

Abstract: The Finite Integration Technique (FIT) is a discretization scheme for Maxwell's equations, where commonly orthogonal tensor product grids are preferred for efficiency reasons. However, orthogonal grids have difficulties to model curved shape boundaries. For the simulation of electro-quasistatic (EQS) fields with the Finite Integration Technique (FIT) a new technique is introduced, which allows an improved geometric modeling of curved boundaries while maintaining orthogonal tensor product grids. The reduction of the geometrical errror …results in the improvement of the solution accuracy. Numerical results for a test problem show the improvement in accuracy with the new approach. Show more

Keywords: finite integration technique, conformal FIT, Electro-Quasistatics, boundary modeling

DOI: 10.3233/JAE-2004-561

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 193-197, 2004

Authors: Siems, Sven Olav | Canders, Wolf-Rüdiger

Article Type: Research Article

Abstract: This paper presents an innovative bearing design for linear and rotatory superconducting magnetic bearings. In order to evaluate the bearings characteristics, two test benches have been set up and several tests for a temperature range from 40 K to 80 K have been performed. A description of the test facilities and the results are presented. Further the realization of the necessary activation process for SMB is discussed and a solution is given, which makes the use …of SMB possible for applications that don't allow any displacement of the suspended part of the machinery. Show more

Keywords: HTSC, SMB, superconducting magnetic bearing, activation process

DOI: 10.3233/JAE-2004-562

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 199-202, 2004

Authors: Wojkiewicz, J.L. | Fauveaux, S. | Redon, N. | Miane, J.L.

Article Type: Research Article

Abstract: Electromagnetic shielding effectiveness properties of polyaniline – polyurethane nanocomposites at microwave frequencies were studied. The conducting blends showed a very low percolation threshold and their electronic properties can be tuned easily with the mass fraction of polyaniline in the blends or through chemical process. Measurements on composite materials were performed in the 8.2 to 18 GHz band using two sets of waveguides. Shielding effectiveness from 30 to 90 dB were found for mono and three layer …samples with a very light weight and good mechanical properties. Show more

Keywords: electromagnetic shielding effectiveness, nanocomposite, polyaniline, microwave

DOI: 10.3233/JAE-2004-563

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 203-206, 2004

Authors: Theodoulidis, Theodoros

Article Type: Research Article

Abstract: A semi-analytical method for modelling electromagnetic fields is applied to eddy current nondestructive evaluation (NDE) to simulate the end effect in tube testing with bobbin coils. The boundary value problem is formulated in terms of the magnetic vector potential and is solved using orthogonal eigenfunctions, the eigenvalues of which are computed as roots of a transcendent complex equation. Closed-form expressions are derived for the impedance change of the coil and the induced eddy currents. The results …are in excellent agreement with those obtained by a 2D-finite element package. Show more

Keywords: eddy current testing, nondestructive evaluation, end effect, edge effect, coil impedance

DOI: 10.3233/JAE-2004-564

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 207-212, 2004