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In contrast to the widely studied problem of recognizing an action given a complete sequence, action anticipation aims to identify the action from only partially available videos. As such, it is therefore key to the success of computer vision applications requiring to react as early as possible, such as autonomous navigation. In this paper, we propose a new action anticipation method that achieves...
We survey some known facts and open questions concerning the global properties of 3+1-dimensional spacetimes containing a compact Cauchy surface. We consider spacetimes with an l-dimensional Lie algebra of space-like Killing fields. For each l ≤ 3, we give some basic results and conjectures on global existence and cosmic censorship.
In this note I discuss the conformal rescaling of spacetimes, with focus on the constraint equations. I give conditions on the Cauchy data at the conformal boundary which are sufficient for regularity, and show how to construct solutions to the conformal constraint equations. Finally, I discuss gauge conditions in the conformal setting and indicate the first steps in analyzing the conformally rescaled...
Nonlinear stability for a class of doubly warped spacetimes is proved. The background spacetimes have negative Einstein factors. It shown that for dimension D≥11 there is a full parameter family of solutions to the vacuum Einstein equations which has Kasner-like singularity and Friedmann like asympotics in the future. In particular, these spacetimes have crushing singularity and are globally foliated...
In this paper we prove a global existence theorem, in the direction of cosmological expansion, for sufficiently small perturbations of a family of spatially compact variants of the k = -1 Friedmann—Robertson—Walker vacuum spacetime. We use a special gauge defined by constant mean curvature slicing and a spatial harmonic coordinate condition, and develop energy estimates through the use of the Be-Robinson...
Broadband Power Line Communications (BPL) is a technology that has proved to be a very suitable option for the deployment of Smart Grid solutions. It provides a low cost, proprietary, high performance future-proof backhaul between Secondary Substations. This paper will focus on the description of the different “Fault Cases” that might occur in medium voltage BPL communication architecture and their...
Telecommunication is a prerequisite for the Smart Grid. Several technologies are available on the market, but there is not a general agreement about which of them, or combination of them, that can enable most of the services for the distribution grid automation. The paper describes the approach of 7th Framework Program European Project INTEGRIS which relies on the hypothesis that there is not a single...
Distribution System Operators are working to improve and extend the level of control of their grid, as response to the new challenges of integrating distribution renewable sources and improving the quality of their service. In doing so, they need also to face up to the problem of reaching their transformer stations via a suitable communication technology, which can guarantee a balanced tradeoff between...
CONTENTS 1. Introduction .............................................................................................5 2. The hyperboloidal initial value problem....................................................9 2.1. Conformal compactifications and Cauchy data....................................9 2.2. Some remarks on non-vacuum initial data...
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