The present development of time service in Brazil, with the application of the TV line-10 method for coordination and synchronization of atomic clocks

Various methods presently used for the dissemination of time at several levels of precision are described along with future projects in the field. Different aspects of time coordination are reviewed and a list of future laboratories participating in a National Time Scale will be presented. A Brazilian Atomic Time Scale will be obtained from as many of these laboratories as possible. The problem of intercomparison between the Brazilian National Time Scale and the International one will be presented and probable solutions will be discussed. Needs related to the TV Line-10 method will be explained and comments will be made on the legal aspects of time dissemination throughout the country

The truth functional hypothesis does not imply the liars paradox

The truth-functional hypothesis states that indicative conditional sentences and the material implication have the same truth conditions. Haze (2011) has rejected this hypothesis. He claims that a self-referential conditional, coupled with a plausible assumption about its truth-values and the assumption that the truth-functional hypothesis is true, lead to a liar’s paradox. Given that neither the self-referential conditional nor the assumption about its truth-values are problematic, the culprit of the paradox must be the truth-functional hypothesis. Therefore, we should reject it. In this paper I argue that, contrary to what Haze thinks, the truth-functional hypothesis is not to blame. In fact, no liar’s paradox emerges when the truth-functional hypothesis is true; it emerges only if it is false

A Contribution to the Modal Identification of the Damping Factor based on the Dissipated Energy

ABSTRACT: The identification of the modal parameters from frequency response functions is a subject that is not new. However, the starting point often comes from the equations that govern the dynamic motion. In this paper, a novel approach is shown, resulting from an analysis that starts on the dissipated energy per cycle of vibration. For lightly damped systems with conveniently spaced modes, it produced quite accurate results in comparison to the direct application of the method of the inverse, both in the numerical and in the experimental examples. It also is a simple technique that can be used to produce quick estimates of the modal damping factors. Furthermore, this is also a contribution to further developments on modal analysis and identification methods as, up to today, the developed technique has not yet been proposed.Final Published versio