The Impact of Sudden Commencements on Ground Magnetic Field Variability: Immediate and Delayed Consequences

The work purpose is the investigation of magnetic field impact upon properties of friction steel surfaces at fit stripping with tightness through manifested effects and their wear visually observed. On the spots of a real contact the magnetic field increases active centers, their amount and saturation with the time of dislocation outlet, and has an influence upon tribo-mating. The external electro-magnetic field promotes the increase of the number of active centers at the expense of dislocations outlet on the contact surface, and the increase of a physical contact area results in friction tie strengthening and growth of a friction factor. By the example of friction pairs of a spentonly unit in the suspension of coach cars there is given a substantiation of actuality and possibility for the creation of technical devices with the controlled factor of friction and the stability of effects achieved is also confirmed experimentally. Investigation methods: the fulfillment of laboratory physical experiments on the laboratory plant developed and patented on bush-rod samples inserted with the fit and tightness. The results of investigations and novelty: the impact of the magnetic field upon the value of a stripping force of a press fit with the guaranteed tightness is defined. Conclusion: there is a possibility to control a friction factor through the magnetic field impact upon a friction contact.

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Sources of Surface Magnetic Field Variability.

10.21236/ada130168 ◽

1983 ◽

Author(s):

W. P. Olson

Keyword(s):

Magnetic Field ◽

Surface Magnetic Field ◽

Field Variability

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THE IMPACT OF A MAGNETIC FIELD ON THE WEAR OF THE GRINDING BODIES, LINING, AND ORE DISINTEGRATION (IN ENGLISH)

Izvestiya vysshikh uchebnykh zavedenii Gornyi zhurnal ◽

10.21440/0536-1028-2018-8-75-82 ◽

2018 ◽

pp. 75-82

Author(s):

KHOPUNOV EDUARD AFANAS'EVICH ◽

◽

SHATAILOV IURII LEONIDOVICH ◽

VORONCHIKHIN SERGEI LEONIDOVICH ◽

SHATAILOV ALEKSANDR IUR'EVICH ◽

...

Keyword(s):

Magnetic Field ◽

The Impact

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Qualitative and quantitative assessment of magnetic vestibular stimulation in humans

Journal of Vestibular Research ◽

10.3233/ves-201538 ◽

2020 ◽

Vol 30 (6) ◽

pp. 353-361

Author(s):

Rebecca S. Dewey ◽

Rachel Gomez ◽

Chris Degg ◽

David M. Baguley ◽

Paul M. Glover

Keyword(s):

Magnetic Field ◽

Objective Measure ◽

Quantitative Measure ◽

Vestibular Stimulation ◽

Initial Study ◽

Clinical Test ◽

Healthy Control ◽

Student’S T ◽

The Impact ◽

The Magnetic Field

The sensation of phantom motion or exhibition of bodily sway is often reported in the proximity of an MR scanner. It is proposed that the magnetic field stimulates the vestibular system. There are a number of possible mechanisms responsible, and the relative contributions of susceptibility on the otolithic receptors and the Lorentz force on the cupulae have not yet been explored. This exploratory study aims to investigate the impact of being in the proximity of a 7.0 T MR scanner. The modified clinical test of sensory interaction on balance (mCTSIB) was used to qualitatively ascertain whether or not healthy control subjects who passed the mCTSIB in normal conditions 1) experienced subjective sensations of dizziness, vertigo or of leaning or shifting in gravity when in the magnetic field and 2) exhibited visibly increased bodily sway whilst in the magnetic field compared to outside the magnetic field. Condition IV of the mCTSIB was video recorded outside and inside the magnetic field, providing a semi-quantitative measure of sway. For condition IV of the mCTSIB (visual and proprioceptive cues compromised), all seven locations/orientations around the scanner yielded significantly more sway than at baseline (p < 0.01 FDR). A Student’s t-test comparing the RMS velocity of a motion marker on the upper arm during mCTSIB condition IV showed a significant increase in the amount of motion exhibited in the field (T = 2.59; d.f. = 9; p = 0.029) compared to outside the field. This initial study using qualitative measures of sway demonstrates that there is evidence for MR-naïve individuals exhibiting greater sway while performing the mCTSIB in the magnetic field compared to outside the field. Directional polarity of sway was not significant. Future studies of vestibular stimulation by magnetic fields would benefit from the development of a sensitive, objective measure of balance function, which can be performed inside a magnetic field.

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Influence of rotating magnetic field on Maxwell saturated ferrofluid flow over a heated stretching sheet with heat generation/absorption

Mechanics & Industry ◽

10.1051/meca/2019022 ◽

2019 ◽

Vol 20 (5) ◽

pp. 502 ◽

Cited By ~ 3

Author(s):

Aaqib Majeed ◽

Ahmed Zeeshan ◽

Farzan Majeed Noori ◽

Usman Masud

Keyword(s):

Magnetic Field ◽

Temperature Field ◽

Velocity Field ◽

Differential Equations ◽

Heat Transport ◽

Viscous Dissipation ◽

Heat Generation ◽

Fluid Motion ◽

Numerical Procedure ◽

The Impact

This article is focused on Maxwell ferromagnetic fluid and heat transport characteristics under the impact of magnetic field generated due to dipole field. The viscous dissipation and heat generation/absorption are also taken into account. Flow here is instigated by linearly stretchable surface, which is assumed to be permeable. Also description of magneto-thermo-mechanical (ferrohydrodynamic) interaction elaborates the fluid motion as compared to hydrodynamic case. Problem is modeled using continuity, momentum and heat transport equation. To implement the numerical procedure, firstly we transform the partial differential equations (PDEs) into ordinary differential equations (ODEs) by applying similarity approach, secondly resulting boundary value problem (BVP) is transformed into an initial value problem (IVP). Then resulting set of non-linear differentials equations is solved computationally with the aid of Runge–Kutta scheme with shooting algorithm using MATLAB. The flow situation is carried out by considering the influence of pertinent parameters namely ferro-hydrodynamic interaction parameter, Maxwell parameter, suction/injection and viscous dissipation on flow velocity field, temperature field, friction factor and heat transfer rate are deliberated via graphs. The present numerical values are associated with those available previously in the open literature for Newtonian fluid case (γ 1 = 0) to check the validity of the solution. It is inferred that interaction of magneto-thermo-mechanical is to slow down the fluid motion. We also witnessed that by considering the Maxwell and ferrohydrodynamic parameter there is decrement in velocity field whereas opposite behavior is noted for temperature field.

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Birkeland current effects on high‐latitude ground magnetic field perturbations

Geophysical Research Letters ◽

10.1002/2015gl065776 ◽

2015 ◽

Vol 42 (18) ◽

pp. 7248-7254 ◽

Cited By ~ 20

Author(s):

K. M. Laundal ◽

S. E. Haaland ◽

N. Lehtinen ◽

J. W. Gjerloev ◽

N. Østgaard ◽

...

Keyword(s):

Magnetic Field ◽

High Latitude ◽

Ground Magnetic

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Influence of the parameters of the gradient impact of a constant magnetic field on the intensification of the tobacco wilting process

Известия вузов. Пищевая технология ◽

10.26297/0579-3009.2020.2-3.25 ◽

2020 ◽

Author(s):

Е.И. Виневский ◽

А.В. Чернов

Keyword(s):

Magnetic Field ◽

Constant Magnetic Field ◽

Permanent Magnets ◽

Moisture Loss ◽

Duration Of Treatment ◽

Linear Gradient ◽

Tobacco Leaves ◽

Tobacco Leaf ◽

Gradient Effect ◽

The Impact

Исследовано влияние параметров градиентного воздействия постоянного магнитного поля (ПМП) на интенсификацию процесса томления табачных листьев. Выдвинута рабочая гипотеза о том, что для стимулирования процесса томления листьев табака необходимо градиентное воздействие на них ПМП, возникающее в результате перемещения листьев относительно системы постоянных магнитов. Введено понятие приведенного коэффициента убыли влаги, равное отношению влажности обработанных листьев к влажности контрольных образцов – необработанных листьев. Установлено, что при использовании точечного градиентного воздействия ПМП на среднюю жилку табачных листьев частотой 0,3 Гц и продолжительности обработки в течение 115–125 с при высоте расположения магнитов 25 мм процесс томления листьев ускоряется на 28,8% в сравнении с контролем. При линейном градиентном воздействии ПМП на табачный лист с частотой 0,3 Гц процесс томления ускоряется на 4,7–15,5% в зависимости от продолжительности обработки (10–40 с). При увеличении продолжительности обработки до 80 с процесс томления листьев табака замедлился. Установлено максимальное ускорение процесса томления листьев табака: при точечном градиентном воздействии ПМП на среднюю жилку табачного листа частотой 0,3 Гц и продолжительности обработки в течение 115–125 с; при линейном градиентном воздействии ПМП на табачный лист частотой 0,3 Гц и продолжительности обработки в течение 55–65 с. The influence of the parameters of the gradient effect of a constant magnetic field (CMF) on the intensification of the process of languishing tobacco leaves is studied. A working hypothesis is put forward that to stimulate the process of tobacco languor, it is necessary to have a gradient effect on them of CMF, which occurs as a result of the movement of leaves relative to the system of permanent magnets. The concept of the reduced coefficient of moisture loss is introduced, which is equal to the ratio of the humidity of treated leaves to the humidity of control samples-untreated leaves. It was found that when using a point gradient effect of CMF on the middle vein of tobacco leaves with a frequency of 0,3 Hz and a duration of processing for 115–125 s at the height of the magnets of 25 mm, the process of leaf languor is accelerated by 28,8% in comparison with the control. When the linear gradient effect of CMF on the tobacco leaf with a frequency of 0,3 Hz, the languor process is accelerated by 4,7–15,5%, depending on the duration of treatment (10–40 s). In the future, with an increase in the processing time to 80 s, the process of languishing tobacco leaves slowed down. The maximum acceleration of the process of languishing tobacco leaves is established: for spot gradient effect of CMF on the mid-veins of tobacco leaf frequency of 0,3 Hz and duration of treatment for 115–125 s; a linear gradient in the impact of CMF on the tobacco sheet with a treatment frequency of 0,3 Hz and duration of treatment for 55–65 s.

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The Impact of Magnetic Field Temporal Sampling on Modeled Surface Electric Fields

Space Weather ◽

10.1029/2018sw001896 ◽

2018 ◽

Vol 16 (11) ◽

pp. 1721-1739 ◽

Cited By ~ 2

Author(s):

Matthew A. Grawe ◽

Jonathan J. Makela ◽

Mark D. Butala ◽

Farzad Kamalabadi

Keyword(s):

Magnetic Field ◽

Electric Fields ◽

Temporal Sampling ◽

The Impact

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Magnetic field transport in compact binaries

Astronomy and Astrophysics ◽

10.1051/0004-6361/202037903 ◽

2020 ◽

Vol 641 ◽

pp. A133

Author(s):

N. Scepi ◽

G. Lesur ◽

G. Dubus ◽

J. Jacquemin-Ide

Keyword(s):

Magnetic Field ◽

Angular Momentum ◽

Magnetic Flux ◽

Large Scale ◽

Compact Object ◽

Light Curves ◽

Momentum Transport ◽

Local Magnetization ◽

Angular Momentum Transport ◽

The Impact

Context. Dwarf novæ (DNe) and low mass X-ray binaries (LMXBs) show eruptions that are thought to be due to a thermal-viscous instability in their accretion disk. These eruptions provide constraints on angular momentum transport mechanisms. Aims. We explore the idea that angular momentum transport could be controlled by the dynamical evolution of the large-scale magnetic field. We study the impact of different prescriptions for the magnetic field evolution on the dynamics of the disk. This is a first step in confronting the theory of magnetic field transport with observations. Methods. We developed a version of the disk instability model that evolves the density, the temperature, and the large-scale vertical magnetic flux simultaneously. We took into account the accretion driven by turbulence or by a magnetized outflow with prescriptions taken, respectively, from shearing box simulations or self-similar solutions of magnetized outflows. To evolve the magnetic flux, we used a toy model with physically motivated prescriptions that depend mainly on the local magnetization β, where β is the ratio of thermal pressure to magnetic pressure. Results. We find that allowing magnetic flux to be advected inwards provides the best agreement with DNe light curves. This leads to a hybrid configuration with an inner magnetized disk, driven by angular momentum losses to an MHD outflow, sharply transiting to an outer weakly-magnetized turbulent disk where the eruptions are triggered. The dynamical impact is equivalent to truncating a viscous disk so that it does not extend down to the compact object, with the truncation radius dependent on the magnetic flux and evolving as Ṁ−2/3. Conclusions. Models of DNe and LMXB light curves typically require the outer, viscous disk to be truncated in order to match the observations. There is no generic explanation for this truncation. We propose that it is a natural outcome of the presence of large-scale magnetic fields in both DNe and LMXBs, with the magnetic flux accumulating towards the center to produce a magnetized disk with a fast accretion timescale.

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Impact of Foreshock Transients on the Flank Magnetopause and Magnetosphere and the Ionosphere

Frontiers in Astronomy and Space Sciences ◽

10.3389/fspas.2021.751244 ◽

2021 ◽

Vol 8 ◽

Author(s):

Chih-Ping Wang ◽

Xueyi Wang ◽

Terry Z. Liu ◽

Yu Lin

Keyword(s):

Magnetic Field ◽

3D Structure ◽

Hybrid Simulation ◽

High Density ◽

Low Density ◽

Simulation Results ◽

Ground Magnetic ◽

Pressure Perturbations

Mesoscale (on the scales of a few minutes and a few RE) magnetosheath and magnetopause perturbations driven by foreshock transients have been observed in the flank magnetotail. In this paper, we present the 3D global hybrid simulation results to show qualitatively the 3D structure of the flank magnetopause distortion caused by foreshock transients and its impacts on the tail magnetosphere and the ionosphere. Foreshock transient perturbations consist of a low-density core and high-density edge(s), thus, after they propagate into the magnetosheath, they result in magnetosheath pressure perturbations that distort magnetopause. The magnetopause is distorted locally outward (inward) in response to the dip (peak) of the magnetosheath pressure perturbations. As the magnetosheath perturbations propagate tailward, they continue to distort the flank magnetopause. This qualitative explains the transient appearance of the magnetosphere observed in the flank magnetosheath associated with foreshock transients. The 3D structure of the magnetosheath perturbations and the shape of the distorted magnetopause keep evolving as they propagate tailward. The transient distortion of the magnetopause generates compressional magnetic field perturbations within the magnetosphere. The magnetopause distortion also alters currents around the magnetopause, generating field-aligned currents (FACs) flowing in and out of the ionosphere. As the magnetopause distortion propagates tailward, it results in localized enhancements of FACs in the ionosphere that propagate anti-sunward. This qualitatively explains the observed anti-sunward propagation of the ground magnetic field perturbations associated with foreshock transients.

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