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The aim of the work was to obtain an auxiliary instrument able to give the magnetic configuration of a magnetron sputtering device for operation with targets, magnetic and non magnetic, with different heights, starting from a device with no detailed information of the source.

An inverse problem has been dealt with. A 2D numerical analysis has been performed, which utilizes as a starting point a model identified with a simple analytical procedure based on measurements.

A satisfactory equivalent model has been identified, and validated in several different conditions.

The proposed approach can be applied when no detailed information of the source is available, in the case of a cathode without a ferromagnetic yoke.

The purpose of this paper is to evaluate the response of the spinal cord, the transmembrane potential, during lumbar magnetic stimulation, using a figure of eight coil.

In order to obtain a precise stimulation of the spinal cord and not the nearby nervous fibres, the coil from the electric circuit of the magnetic stimulator is optimized. The new proposed design is based on the turns’ placement inside the coil, the number of turns required to produce activation. Once the coil configuration is established, the paper addresses other issues that need to be solved: reducing power consumption (the low efficiency of power transfer from the coil to the tissue is a major drawback) and reducing coil heating.

The traditional commercial coils, used for magnetic stimulation in some preliminary experiments, had proved their inability to specifically stimulate the target tissue, without activating the surrounding areas and the low efficiency of power transfer from the coil to the nervous tissue. A more realistic modelling of the stimulating coil, based on the distribution of turns inside the coil can lead to directly stimulation of the spinal cord, during lumbar magnetic stimulation.

If the electrical circuit of the magnetic stimulator is improved, the direct stimulation of the spinal cord is obtained; so, this technique could facilitate functional motor activities, including standing and stepping in paralyzed people, without requiring implantation of electrodes like in electrical stimulation.

The authors underlined that the spinal cord stimulation can be achieved by magnetic stimulation, only if the parameters of the stimulator circuit are optimized. Therefore an original and realistic modelling of the inductive coil was proposed based on number and turns’ distribution within the coil. The coil is designed so that reducing the excessive heating makes it difficult in obtaining a more frequent repetition of stimulus.

The purpose of this paper is to compute the values of induced voltages and currents in an underground gas pipeline, which shares the same right of way with a high voltage power line (HVPL) in unbalanced phase currents regime, in order to detect the possibility of the AC corrosion occurring in the pipeline.

The analysis of the induced voltages in metallic structures (gas pipeline) was done using a professional analysis and modeling software which uses the electromagnetic field method.

It was shown that during fault conditions, large currents and voltages are induced on the pipelines, which may pose a threat to operating personnel and equipment. Induced voltages also occur in cases of unbalanced phase currents of the HVPL, which may pose a threat voltage that could lead to damages of the underground gas pipeline due to corrosion phenomena.

Because the electromagnetic field approach involves complicated analytical expression and introduces serious computational difficulties, among which matrix of coefficients representing the set of simultaneous linear equations, the use of professional analysis and modeling software is justified.

The paper reveals that even in unbalanced phase currents regime of the HVPL, the nearby metallic structures that share the same right of way with the transmission line are in danger of degradation because of the induced voltages, whose values exceed the values imposed by regulation.