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The flux gate for measurement of size and direction of magnetic field of the Earth and for measurement of local magnetic fields, applying the unidirectional pulse scheme in an excitement chain are examined. The article treats the benefits of ferroprobes with pulse excitement in comparison with the similar sensors with sinusoidal excitement. According to the original circuit proposed by the authors of the article flux gate sensor for measurement of a local magnetic field with two ferroprobes for the purpose of compensation of the Earth’s magnetic field is designed. The experiment with flux gate sensors which contain various quantities of rounds in an output winding and a permanent magnet is carried out. The factors that influence the output voltage of the sensor are examined during the experiment. The regression equation for the ferroprobe by the experimental data is obtained. The regression is important for development of similar measuring systems. First of all, the results of the research are important for the analysis of technical characteristics of magneto-modulation sensors, and for ferroprobes design in aircraft industry.

Results of geodetic in-situ observations of ice-flow velocities in the southern part of subglacialLakeVostokare combined with data sets of the ice surface topography, ice thickness, surface accumulation, basal accretion and firn/ice density for interpretations regarding the glaciological setting of theLakeVostoksystem. Based on the ice-flow velocities and the ice thickness, mean surface accumulation rates are derived applying the flux gate method. These are representative for surface segments extending from the southern part ofLakeVostokto the Ridge B ice divide. They are consistent with the present-day accumulation rate at Vostok station and its variation upstream and thus suggest that the area has been close to steady state. In addition, ice-flow dynamics are investigated along a flow line segment extending from26 kmupstream to12 kmdownstream from Vostok station. The analysis suggests deficiencies in current modelling approaches within the transition zone from floating to grounded ice.

The development of a control device of ship hull mechanical stresses during cargo and ballast operations based on a magnetometric method is proposed in the paper. The proposed method provides controlling mechanical stresses in real time, unambiguously connects elastic stresses with a controlled variable, i.e. a retentive magnetism. Herewith, the device, carrying out this method, is constructed on the basis of flux gates, making it simple and reliable in operation. The estimation of metrological characteristics of the device elements controlling mechanical stresses of a ship hull was made. For this purpose, an experimental study of constituent elements of the device was conducted. For compensating the Earth magnetic field, it was suggested using an additional magnetometric channel. The obtained research results allow developing and manufacturing a commercial prototype of a fluxgate continuous monitoring device of ship hull mechanical stresses. [ABSTRACT FROM AUTHOR]