scholarly journals Valyashko – the founder of a new approach to the study of the magnetic field of the ocean

2020 ◽  
Vol 48 (1) ◽  
pp. 121-124
Author(s):  
A. M. Gorodnitskiy ◽  
N. A. Shishkina
Keyword(s):  
Magnetic Field ◽  
Personal Computers ◽  
Automated System ◽  
New Approach ◽  
Geophysical Information ◽  
Long Life ◽  
The Magnetic Field

G.M. Valyashko is one of the founders of the new methodology for processing and interpreting the results of marine magnetometric measurements. In the 70s, he created an automated system for collecting and processing geophysical information, which was called “Sailor”. G.M. Valyashko continuously improved the Sailor, who lived a long life on the ships of the Institute of Oceanology from the first on-board computers to modern personal computers.

scholarly journals Comparison of the measured and modelled electron densities and temperatures in the ionosphere and plasmasphere during 20-30 January, 1993

2000 ◽  
Vol 18 (10) ◽  
pp. 1257-1262 ◽  
Author(s):  
A. V. Pavlov ◽  
T. Abe ◽  
K.-I. Oyama
Keyword(s):  
Magnetic Field ◽  
Heat Flux ◽  
Electron Temperature ◽  
Field Line ◽  
Electron Density ◽  
Magnetic Field Line ◽  
New Approach ◽  
Additional Heating ◽  
Vibrational Levels ◽  
The Magnetic Field

Abstract. We present a comparison of the electron density and temperature behaviour in the ionosphere and plasmasphere measured by the Millstone Hill incoherent-scatter radar and the instruments on board of the EXOS-D satellite with numerical model calculations from a time-dependent mathematical model of the Earth's ionosphere and plasmasphere during the geomagnetically quiet and storm period on 20–30 January, 1993. We have evaluated the value of the additional heating rate that should be added to the normal photoelectron heating in the electron energy equation in the daytime plasmasphere region above 5000 km along the magnetic field line to explain the high electron temperature measured by the instruments on board of the EXOS-D satellite within the Millstone Hill magnetic field flux tube in the Northern Hemisphere. The additional heating brings the measured and modelled electron temperatures into agreement in the plasmasphere and into very large disagreement in the ionosphere if the classical electron heat flux along magnetic field line is used in the model. A new approach, based on a new effective electron thermal conductivity coefficient along the magnetic field line, is presented to model the electron temperature in the ionosphere and plasmasphere. This new approach leads to a heat flux which is less than that given by the classical Spitzer-Harm theory. The evaluated additional heating of electrons in the plasmasphere and the decrease of the thermal conductivity in the topside ionosphere and the greater part of the plasmasphere found for the first time here allow the model to accurately reproduce the electron temperatures observed by the instruments on board the EXOS-D satellite in the plasmasphere and the Millstone Hill incoherent-scatter radar in the ionosphere. The effects of the daytime additional plasmaspheric heating of electrons on the electron temperature and density are small at the F-region altitudes if the modified electron heat flux is used. The deviations from the Boltzmann distribution for the first five vibrational levels of N2(v) and O2(v) were calculated. The present study suggests that these deviations are not significant at the first vibrational levels of N2 and O2 and the second level of O2, and the calculated distributions of N2(v) and O2(v) are highly non-Boltzmann at vibrational levels v > 2. The resulting effect of N2(v > 0) and O2(v > 0) on NmF2 is the decrease of the calculated daytime NmF2 up to a factor of 1.5. The modelled electron temperature is very sensitive to the electron density, and this decrease in electron density results in the increase of the calculated daytime electron temperature up to about 580 K at the F2 peak altitude giving closer agreement between the measured and modelled electron temperatures. Both the daytime and night-time densities are not reproduced by the model without N2(v > 0) and O2(v > 0), and inclusion of vibrationally excited N2 and O2 brings the model and data into better agreement.Key words: Ionosphere (ionospheric disturbances; ionosphere-magnetosphere interactions; plasma temperature and density)  

The magnetic field inside a long solenoid—a new approach

2010 ◽  
Vol 45 (5) ◽  
pp. 529-532
Author(s):  
David Andrews ◽  
Kevin Carlton ◽  
David Lisgarten
Keyword(s):  
Magnetic Field ◽  
New Approach ◽  
The Magnetic Field

scholarly journals Computer technology for interpreting vector measurements of the magnetic field

2021 ◽  
Vol 43 (5) ◽  
pp. 219-231
Author(s):  
T. L. Mikheevа ◽  
O. P. Lapinа
Keyword(s):  
Magnetic Field ◽  
Inverse Problem ◽  
Computer Technology ◽  
Initial Approximation ◽  
Field Vector ◽  
Automated System ◽  
Geological Interpretation ◽  
Algorithmic Support ◽  
Vector Information ◽  
The Magnetic Field

Computer technology is presented to solve the inverse problem of magnetic field vector measurements using software and algorithmic support for an automated system to interpret potential fields. The technology includes constructing a numerical model of the magnetic field of the studied area, forming an initial approximation model, assessing the depth of the sources and their magnetization. An approximation structure is used to describe the sources of anomalies (a set of uniformly magnetized polygonal prisms). To solve the problem, we used real vector measurements of the magnetic field by the components Xа, Ya, Zа, Та in the sections of Gruzsko South and Gruzsko Severnaya. Geologically, the area belongs to the central part of the Ukrainian Shield — the Kirovograd tectonic megablock. The area of work is confined to the Subotsko-Moshorin latitudinal fault zone. The possibility of comparing the results of the interpretation of anomalies on each profile by the components of the anomalous magnetic field increases the reliability of the geological interpretation of magnetic prospecting data compared to the interpretation of modular surveys. The presence of vector measurements greatly facilitates the ability to determine the parameters of anomalous objects, which makes it possible to obtain more reliable solutions to the inverse problem. The use of vector information makes it possible to localize geological sources more successfully, thereby reducing the amount of work.

The Calculation of the Magnetic Field Produced by an Arbitrary Shaped Current-Carrying Wire in its Plane

2013 ◽  
Vol 756-759 ◽  
pp. 3687-3691 ◽  
Author(s):  
Zhou Yu ◽  
Chang Han Xiao ◽  
Huan Wang ◽  
Yao Zhong Zhou
Keyword(s):  
Magnetic Field ◽  
Straight Line Segment ◽  
Computational Time ◽  
Improved Method ◽  
New Approach ◽  
Line Segments ◽  
Steady Current ◽  
Straight Line ◽  
Coordinate Rotation ◽  
The Magnetic Field

Instead of performing the integration explicitly to calculate the magnetic field from an arbitrary shaped wire, an improved method was proposed. The magnetic field generated by a straight line segment carrying steady current was calculated based on the Biot-Savart law. The new approach is to break the wire down into a number of straight line segments in its plane. According to the principle of vector superposition and coordinate rotation, the magnetic field from the complete current wire can then be calculated by summing the contribution from each of the separate straight line pieces. The simulation results show that the proposed numerical method has high accuracy and faster computational time and is efficient and convenient to the application in projects.

New scheme for computing the magnetic field resulting from a uniformly magnetized arbitrary polyhedron

Geophysics ◽  
1999 ◽  
Vol 64 (1) ◽  
pp. 70-74 ◽  
Author(s):  
D. Guptasarma ◽  
B. Singh
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Arbitrary Shape ◽  
Numerical Evaluation ◽  
Solid Angle ◽  
New Approach ◽  
Polygonal Surface ◽  
Magnetic Poles ◽  
The Magnetic Field

The magnetic field at any point outside a uniformly magnetized polyhedron of arbitrary shape is obtained by adding the fields resulting from the effective free magnetic poles on each of the polygonal surfaces of the polyhedron. For each polygonal surface, the components of the field at the point of observation are expressed in terms of new line integrals around the edges of the polygon and the solid angle subtended by the polygon at the point of observation. The line integrals are standard elementary forms. This new approach makes the numerical evaluation of the magnetic fields for such models much simpler and faster than previously published methods.

MagiThings

2013 ◽  
Vol 5 (3) ◽  
pp. 23-41 ◽  
Author(s):  
Hamed Ketabdar ◽  
Amin Haji-Abolhassani ◽  
Mehran Roshandel
Keyword(s):  
Magnetic Field ◽  
User Interface ◽  
Mobile Devices ◽  
Mobile Device ◽  
Data Entry ◽  
Field Pattern ◽  
New Approach ◽  
Wide Range ◽  
Device Interaction ◽  
The Magnetic Field

The theory of around device interaction (ADI) has recently gained a lot of attention in the field of human computer interaction (HCI). As an alternative to the classic data entry methods, such as keypads and touch screens interaction, ADI proposes a touchless user interface that extends beyond the peripheral area of a device. In this paper, the authors propose a new approach for around mobile device interaction based on magnetic field. Our new approach, which we call it “MagiThings”, takes the advantage of digital compass (a magnetometer) embedded in new generation of mobile devices such as Apple’s iPhone 3GS/4G, and Google’s Nexus. The user movements of a properly shaped magnet around the device deform the original magnetic field. The magnet is taken or worn around the fingers. The changes made in the magnetic field pattern around the device constitute a new way of interacting with the device. Thus, the magnetic field encompassing the device plays the role of a communication channel and encodes the hand/finger movement patterns into temporal changes sensed by the compass sensor. The mobile device samples momentary status of the field. The field changes, caused by hand (finger) gesture, is used as a basis for sending interaction commands to the device. The pattern of change is matched against pre-recorded templates or trained models to recognize a gesture. The proposed methodology has been successfully tested for a variety of applications such as interaction with user interface of a mobile device, character (digit) entry, user authentication, gaming, and touchless mobile music synthesis. The experimental results show high accuracy in recognizing simple or complex gestures in a wide range of applications. The proposed method provides a practical and simple framework for touchless interaction with mobile devices relying only on an internally embedded sensor and a magnet.

scholarly journals THE CHARGED NEUTRINO: A NEW APPROACH TO THE SOLAR NEUTRINO PROBLEM

1994 ◽  
Vol 09 (16) ◽  
pp. 1479-1488 ◽  
Author(s):  
A.YU. IGNATIEV ◽  
G.C. JOSHI
Keyword(s):  
Magnetic Field ◽  
Solar Neutrino ◽  
Neutrino Flux ◽  
Convective Zone ◽  
Electron Charge ◽  
New Approach ◽  
Solar Neutrino Problem ◽  
The Earth ◽  
Solar Neutrino Flux ◽  
The Magnetic Field

We have considered the effect of the reduction of the solar neutrino flux on earth due to the deflection of the charged neutrino by the magnetic field of the solar convective zone. The antisymmetry of this magnetic field about the plane of the solar equator induces the anisotropy of the solar neutrino flux thus creating the deficit of the neutrino flux on the earth. The deficit has been estimated in terms of solar and neutrino parameters and the condition of a 50% deficit has been obtained: Qν grad H≥10−18 eG/cm where Qν is the neutrino electric charge, grad H is the gradient of the solar toroidal magnetic field, e is the electron charge. Some attractive experimental consequences of this scenario are qualitatively discussed.

scholarly journals Euler potentials for two layers with non-constant current densities in the ambient magnetic field aligned to the layers

2016 ◽  
Vol 34 (12) ◽  
pp. 1165-1173
Author(s):  
Marek Vandas ◽  
Eugene P. Romashets
Keyword(s):  
Magnetic Field ◽  
Current Density ◽  
Previous Treatment ◽  
Homogeneous Magnetic Field ◽  
Constant Current ◽  
Constant Current Density ◽  
New Approach ◽  
Current Densities ◽  
The Magnetic Field ◽  
Birkeland Currents

Abstract. The Euler potentials for two current layers aligned to an ambient homogeneous magnetic field are found. Previous treatment of such a system assumed constant current density in the layers. However, the magnetic field becomes infinite at the edges. The new approach eliminates this inconsistency by introducing an inhomogeneous current density. Euler potentials are constructed semi-analytically for such a system. Charged-particle motion and trapping in it are examined by this representation. Using Euler potentials, the influence of current sheets of zero and non-zero thicknesses on energetic-particle fluxes is investigated, and characteristic flux variations near the sheets are presented. The results can be applied to Birkeland currents.

scholarly journals Particle Acceleration and Nonthermal Energy Release as an Effect of Magnetoactive Disk Accretion Onto Gravitating Center

1994 ◽  
Vol 142 ◽  
pp. 959-961
Author(s):  
N. R. Ikhsanov ◽  
L. A. Pustil’nik
Keyword(s):  
Magnetic Field ◽  
Particle Acceleration ◽  
Energy Release ◽  
Electric Fields ◽  
Double Layers ◽  
Disk Accretion ◽  
New Approach ◽  
Effective Particle ◽  
Z Pinch ◽  
The Magnetic Field

AbstractObservations of GRO and UHEGR show that a number of Galactic and extragalactic accreting systems release most of their energy in the ultrarelativistic energy range (more than GeV). This result contradicts one of the principal conclusions of the standard models of accretion about a predominantly thermal character of energy release. This contradiction is caused by ignoring in the standard approach the processes of generation and amplification of magnetic field in the case of accretion onto a magnetized gravitating center. A new approach taking into account the processes mentioned above is applied to disk accretion onto a nonmagnetized gravitating center, as well as onto a magnetosphere. It is shown that in both cases the accretion is strictly controlled by the magnetic field, which leads to new conditions of equilibrium and stability and turns on nonthermal processes of energy release. The resulting configuration of the magnetic field, in which the main energy release takes place in both cases, is called “Z-pinch,” and is formed in the polar region of an accreting object. Effective particle acceleration occurs in it owing to the chain of MHD and resistive plasma instabilities, resulting in current discontinuity with the formation of “double layers” and generation of electric fields close to the Dreicer limit in them. The maximum energies of the accelerated particles are limited by the value 10 EeV, that coincides with the results of UHEGR observations.Subject headings: acceleration of particles — accretion, accretion disks — gamma rays: theory — MHD

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