Abstract.We present the results of recent friction experiments in which a MEMS-based sensing device is used to measure both the normal and tangential stress fields at the base of a rough elastomer film in frictional contact with smooth, rigid, glass indentors. We consider successively multicontacts under (i) static normal loading by a spherical indentor and (ii) frictional steady sliding conditions against a cylindrical indentor, for an increasing normal load. In both cases, the measured fields are compared to elastic calculations assuming (i) a smooth interface and (ii) Amontons' friction law. In the static case, significant deviations are observed which decrease with increasing load and which vanish when a lubricant is used. In the steady sliding case, Amontons' law reproduces rather satisfactorily the experiments provided that the normal/tangential coupling at the contact interface is taken into account. We discuss the origin of the difference between the Amontons fields and the measured ones, in particular the effect of the finite normal and tangential compliances of the multicontact interface.

The objective of this paper is to show the influence of the duration of a lightning pulse on OPGW cables, using the BOR-FDTD method and analyzing the current density distribution along the radial direction for different pulse widths.

+55-15-32359209 -Multiconductor OPGW cables have a double function: they serve for lightning protection and as a communications channel. In this work, we present some results of the analysis of current density distributions in these cables obtained by an analytical method and using the FEMLAB software.-Cables, waveguide theory, current density.