scholarly journals Anomalous field-induced growth of fluctuations in dynamics of a biased intruder moving in a quiescent medium

2013 ◽  
Vol 87 (2) ◽  
Author(s):  
Olivier Bénichou ◽  
Carlos Mejía-Monasterio ◽  
Gleb Oshanin
Keyword(s):  
2018 ◽  
Vol 939 (9) ◽  
pp. 2-9
Author(s):  
V.V. Popadyev

The author analyzes the arguments in the report by Robert Kingdon, Petr Vanicek and Marcelo Santos “The shape of the quasigeoid” (IX Hotin-Marussi Symposium on Theoretical Geodesy, Italy, Rome, June 18 June 22, 2018), which presents the criticisms for the basic concepts of Molodensky’s theory, the normal height and height anomaly of the point on the earth’s surface, plotted on the reference ellipsoid surface and forming the surface of a quasigeoid. The main advantages of the system of normal heights, closely related to the theory of determining the external gravitational field and the Earth’s surface, are presented. Despite the fact that the main advantage of Molodensky’s theory is the rigorous determining the anomalous potential on the Earth’s surface, the use of the system of normal heights can be shown and proved separately. To do this, a simple example is given, where the change of marks along the floor of a strictly horizontal tunnel in the mountain massif is a criterion for the convenience of the system. In this example, the orthometric heights show a change of 3 cm per 1.5 km, which will require corrections to the measured elevations due the transition to a system of orthometric heights. The knowledge of the inner structure of the rock mass is also necessary. It should be noted that the normal heights are constant along the tunnel and behave as dynamic ones and there is no need to introduce corrections. Neither the ellipsoid nor the quasi-geoid is a reference for normal heights, because so far the heights are referenced to initial tide gauge. The points of the earth’s surface are assigned a height value; this is similar to the ideas of prof. L. V. Ogorodova about the excessive emphasis on the concept of quasigeoid. A more general term is the height anomaly that exists both for points on the Earth’s surface and at a distance from it and decreases together with an attenuation of the anomalous field.


1993 ◽  
Vol 62 (2) ◽  
pp. 416-419 ◽  
Author(s):  
Hideyuki Sato ◽  
Tadashi Kumano ◽  
Yuji Aoki ◽  
Takeo Kaneko ◽  
Ryôichi Yamamoto

1998 ◽  
Vol 67 (6) ◽  
pp. 2142-2143 ◽  
Author(s):  
Hitoshi Sugawara ◽  
Yuji Aoki ◽  
Hideyuki Sato ◽  
Noriaki Sato ◽  
Takemi Komatsubara

2007 ◽  
Vol 73 (2) ◽  
pp. 241-256 ◽  
Author(s):  
N. MAZUR ◽  
E. FEDOROV ◽  
V. PILIPENKO ◽  
A. LEONOVICH

Abstract.The efficiency of the Alfvén impulse excitation in the auroral zone of the terrestrial magnetosphere upon the onset of the anomalous field-aligned resistance has been estimated. The impulsive disturbance excited during the onset of anomalous field-aligned resistance and electric field may signify the transition of a global magnetospheric instability into the explosive phase with positive feedback. We consider the self-consistent problem on excitation of anomalous resistance at the front of field-aligned current and reverse influence upon it from the induced currents. The analytical solution of the self-consistent problem has shown that during the entrance of field-aligned current front into the anomalous resistivity layer (ARL) an Alfvénic impulse is generated. The interaction of the external current with ARL results in the delay of the current growth. The impulse duration and delay time depend on the ratio between the Alfvén damping scale and external current width. The solution obtained indicates the possibility of using the Alfvénic impulse as an indicator of distant occurrence of anomalous resistance.


2019 ◽  
Vol 13 (2) ◽  
pp. 229-235
Author(s):  
Brett N. Williams ◽  
Filip Bauwens ◽  
Thomas Haskett ◽  
Steven Vandeweghe ◽  
Todd A. Corsetti ◽  
...  

1982 ◽  
Vol 19 (7) ◽  
pp. 1507-1517 ◽  
Author(s):  
Michel Menvielle ◽  
Jean-Claude Rossignol

Anomalous transient variations of the geomagnetic field in northern Morocco and southern Spain have been described previously for periods ranging from 10 min to 2 h. These results have been reinvestigated with regard to their tectonic implications.The main result obtained is evidence for a conductive structure that electrically connects the Atlantic Ocean to the Mediterranean Sea. This conductive structure coincides with a zone of fractures, extending over several hundreds of kilometres and deeply penetrating the crust, that may form the southeastern boundary of the Alboran block.We also show that the deviation and channeling of electric currents by lateral contrasts of conductivity may account for most of the features of the observed anomalous field in southern Spain and northern Morocco.


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