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We introduce a novel longwave polarimetric-based approach to man-made object detection that departs from a more traditional direct use of Stokes parameters. The approach exploits the spatial statistics on two coregistered vertical and horizontal polarization components of the images, where differences of spatial second-order statistics in the bivariate space reveal that man-made objects are separable from natural objects while holding invariant to diurnal cycle variation and geometry of illumination. We exploit the invariant feature using the Bayes decision rule based only on probabilities. Experimental results on a challenging data set, covering a 24-h diurnal cycle, show the effectiveness of the new approach on detecting anomalies; three military tank surrogates posed at different aspect angles are detectable in a natural clutter background. These results yield a negligible false alarm rate as the heating components of the tank surrogates were turned off during data collection. [ABSTRACT FROM AUTHOR]

Outsourcing of maintenance activities from the core distribution operator business prompted the reorganization of the operations sequence of activities and affects, to some extent, the reliability of the distribution network. Repair times, a major component in the reliability calculations, arrive to a new understanding from operations point of view and the adequacy of established probabilistic representations has to be assessed. This paper proposes a mechanism to identify the layout of the sequence of activities for distribution component repair, resulting from reorganization, and revises the adequate representation of the times associated with various stages of the derived repair process. Statistical-based techniques employing estimates of distribution parameters and hypothesis testing serve to determine probabilistic distributions. The validity of the independence assumption for the random variables associated with individual times which compose the repair time is checked via statistical methods in order to confirm applicability of probabilistic-based calculations. By means of such a mechanism, an objective analysis of the time components of the repair time can be conducted, such as areas of improvement, and can be outlined. The results obtained for a large real power distribution system are presented. [ABSTRACT FROM AUTHOR]