Measurements of the Magnetic Fields Generated by Electronic Devices Installed on Railways Rolling Stock

2018 ◽  
pp. 99-106
Author(s):  
John, Łukasz ◽  
Dłużniewski, Artur
2013 ◽  
Vol 303-306 ◽  
pp. 49-52 ◽  
Author(s):  
Ming Long ◽  
Guo Liang Hu ◽  
Shao Long Wang

A three layer sandwich beam with an aluminum face sheet and a magnetorheological elastomer (MRE) core was fabricated. The transverse motion equations of MRE cantilever sandwich beam under non-homogeneous magnetic fields were derived with the fine Mead-Markus model, and the first natural frequency of the beam were calculated. Meanwhile, the first natural frequency of the beam was also simulated using ANSYS software. The numerical simulations accorded with theoretical results in general. The results are expected to provide guidance to develop broadband vibration isolation devices for railways and rolling stock.


The information about the ASONIKA-EMC program, intended for calculating the distribution of electric and magnetic fields intensity inside and outside of the electronic devices housings, as well as for determining the ef¬fectiveness of shielding electric and magnetic fields at effect of the electromagnetic waves in the frequency range 10...30 000 MHz, is adduced. Functional capabilities are described, an example of calculation and analysis of calculation results is adduced. Keywords: radio engineering device; modeling; electric field; magnetic field; electric field intensity; magnetic field strength; shielding.


2018 ◽  
Vol 7 (4.3) ◽  
pp. 115
Author(s):  
Iryna Shvedchykova ◽  
Jasim Mohmed Jasim Jasim ◽  
Olexandr Shevchenko ◽  
Iryna Soloshych

The article is devoted to the problem in diagnostic for axes of wheel sets of rolling stock at the railroad lines. It shows that the time counter method of magnetic powder control has low productivity and is characterized by high subjectivity and the impossibility of automating the control process. To eliminate these defects and improve the reliability for detection of defects on the surface of the stepped axis a method based on the using of fluxgate transducer is proposed. It was carried out the analysis of magnetic fields near the surface of the axles of wheel sets using the developed mathematical models, which made it possible to calculate both the defect fields and the stray field of the stepped surface of axis. Spatial and frequency selection of useful signals based on the analysis of information parameters of magnetic fields of stray of surface and subsurface defects and fields induced by the stepped surface of the magnetized axis is proved.  


1994 ◽  
Vol 144 ◽  
pp. 559-564
Author(s):  
P. Ambrož ◽  
J. Sýkora

AbstractWe were successful in observing the solar corona during five solar eclipses (1973-1991). For the eclipse days the coronal magnetic field was calculated by extrapolation from the photosphere. Comparison of the observed and calculated coronal structures is carried out and some peculiarities of this comparison, related to the different phases of the solar cycle, are presented.


1994 ◽  
Vol 144 ◽  
pp. 21-28 ◽  
Author(s):  
G. B. Gelfreikh

AbstractA review of methods of measuring magnetic fields in the solar corona using spectral-polarization observations at microwaves with high spatial resolution is presented. The methods are based on the theory of thermal bremsstrahlung, thermal cyclotron emission, propagation of radio waves in quasi-transverse magnetic field and Faraday rotation of the plane of polarization. The most explicit program of measurements of magnetic fields in the atmosphere of solar active regions has been carried out using radio observations performed on the large reflector radio telescope of the Russian Academy of Sciences — RATAN-600. This proved possible due to good wavelength coverage, multichannel spectrographs observations and high sensitivity to polarization of the instrument. Besides direct measurements of the strength of the magnetic fields in some cases the peculiar parameters of radio sources, such as very steep spectra and high brightness temperatures provide some information on a very complicated local structure of the coronal magnetic field. Of special interest are the results found from combined RATAN-600 and large antennas of aperture synthesis (VLA and WSRT), the latter giving more detailed information on twodimensional structure of radio sources. The bulk of the data obtained allows us to investigate themagnetospheresof the solar active regions as the space in the solar corona where the structures and physical processes are controlled both by the photospheric/underphotospheric currents and surrounding “quiet” corona.


2000 ◽  
Vol 179 ◽  
pp. 263-264
Author(s):  
K. Sundara Raman ◽  
K. B. Ramesh ◽  
R. Selvendran ◽  
P. S. M. Aleem ◽  
K. M. Hiremath

Extended AbstractWe have examined the morphological properties of a sigmoid associated with an SXR (soft X-ray) flare. The sigmoid is cospatial with the EUV (extreme ultra violet) images and in the optical part lies along an S-shaped Hαfilament. The photoheliogram shows flux emergence within an existingδtype sunspot which has caused the rotation of the umbrae giving rise to the sigmoidal brightening.It is now widely accepted that flares derive their energy from the magnetic fields of the active regions and coronal levels are considered to be the flare sites. But still a satisfactory understanding of the flare processes has not been achieved because of the difficulties encountered to predict and estimate the probability of flare eruptions. The convection flows and vortices below the photosphere transport and concentrate magnetic field, which subsequently appear as active regions in the photosphere (Rust & Kumar 1994 and the references therein). Successive emergence of magnetic flux, twist the field, creating flare productive magnetic shear and has been studied by many authors (Sundara Ramanet al.1998 and the references therein). Hence, it is considered that the flare is powered by the energy stored in the twisted magnetic flux tubes (Kurokawa 1996 and the references therein). Rust & Kumar (1996) named the S-shaped bright coronal loops that appear in soft X-rays as ‘Sigmoids’ and concluded that this S-shaped distortion is due to the twist developed in the magnetic field lines. These transient sigmoidal features tell a great deal about unstable coronal magnetic fields, as these regions are more likely to be eruptive (Canfieldet al.1999). As the magnetic fields of the active regions are deep rooted in the Sun, the twist developed in the subphotospheric flux tube penetrates the photosphere and extends in to the corona. Thus, it is essentially favourable for the subphotospheric twist to unwind the twist and transmit it through the photosphere to the corona. Therefore, it becomes essential to make complete observational descriptions of a flare from the magnetic field changes that are taking place in different atmospheric levels of the Sun, to pin down the energy storage and conversion process that trigger the flare phenomena.


Sign in / Sign up

Export Citation Format

Share Document