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Publications associées (8)
Characteristic classes as complete obstructions
In the first part of this paper, we propose a uniform interpretation of characteristic classes as obstructions to the reduction of the structure group and to the existence of an equivariant extension of a certain homomorphism defined a priori only on a sin ...
SPRINGER HEIDELBERG2019Learning Hawkes Processes from a Handful of Events
Patrick Thiran, Matthias Grossglauser, William Trouleau, Farnood Salehi
Learning the causal-interaction network of multivariate Hawkes processes is a useful task in many applications. Maximum-likelihood estimation is the most common approach to solve the problem in the presence of long observation sequences. However, when only ...
2019Towards new invariants for principal bundles
We investigate the theory of principal bundles from a homotopical point of view. In the first part of the thesis, we prove a classification of principal bundles over a fixed base space, dual to the well-known classification of bundles with a fixed structur ...
EPFL2017Cellular Homotopy Excision
There is a classical "duality" between homotopy and homology groups in that homotopy groups are compatible with homotopy pullbacks (every homotopy pullback gives rise to a long exact sequence in homotopy), while homology groups are compatible with homotopy ...
EPFL2016Homotopy Excision And Cellularity
Jérôme Scherer, Kay Remo Werndli
Consider a push-out diagram of spaces C B, construct the homotopy push-out, and then the homotopy pull-back of the diagram one gets by forgetting the initial object A. We compare the difference between A and this homotopy pull-back. This difference ...
Annales Inst Fourier2016Conditionally flat functors on spaces and groups
Consider a fibration sequence of topological spaces which is preserved as such by some functor , so that is again a fibration sequence. Pull the fibration back along an arbitrary map into the base space. Does the pullback fibration enjoy the same property? ...
Springer-Verlag Italia Srl2015On some weak extensions of AES and BES
In 2002, Murphy and Robshaw introduced an extension BES of AES and argued this could compromise the security of AES. We introduce here two block-ciphers CES and big-BES that are some extensions of the AES and BES respectively in the spirit of Hensel liftin ...
2004Squeeze flow of concentrated long fibre suspensions: experiments and model
Experimental squeeze flow results show that the behaviour of concentrated short fibre suspensions and concentrated long fibre suspensions impregnated with polymer melts are qualitatively different. Short fibre suspensions have a low yield stress, have an o ...
2002