Search results for "Cohérence"

Effet du relief sur la variabilité de descripteurs des saisons des pluies en Afrique de l’Est.

2011

6 pages; International audience; Les variations spatiales des différents descripteurs des saisons des pluies tropicales (durée, fréquence et intensitédes pluies…) sont mal connues, notamment en régions accidentées. Elles ont pourtant une réelle incidence agroclimatique.Au Kenya, ces descripteurs sont fortement contraints par la géographie, y compris aux échelles fines. L’exemple du versantest du Mont Kenya montre une gamme de conditions agro-écologiques, sous l’influence du schéma général reliantl’augmentation des pluies avec l’altitude. L’altitude influence principalement la durée des deux saisons des pluies (Long etShort rains). La fréquence des jours de pluies est également modulée par l…

Alignment of linear molecules by short duration laser pulses

2005

Alignment of linear molecules is efficiently induced by strong linearly polarized laser pulses. In the case of short pulses with respect to molecular rotation, periodic alignment appears in field-free conditions after the extinction of the field. This manuscript presents three techniques where the value of allows to quantify alignment without molecular dissociation nor additional alignment. They use a weak time-delayed probe pulse which experiences the optical properties of an aligned sample and shows modification of its characteristics. The first of them measures a depolarization due to the birefringence of the sample. The second one is based on the defocusing produced by the spatial distr…

Le problème de la cohérence de la théorie du mouvement chez Patocka : enracinement, percée et ébranlement du sens

2012

Quantum Information by Adiabatic Passage : Quantum Gates and Decoherence

2007

The first part of this thesis is about adiabatic quantum processes designed for the implementation of quantum logic gates, the elementary components of quantumcomputers, by the interaction of pulsed laser fields with atoms. The adiabaticmethods allow robust processes, i.e. which are not sensitive to the fluctuationsof experimental parameters. The processes described in this thesis only requireaccurate control of the polarisations and the relative static phases of thelaser fields. These processes allow the implementation of a universal set ofquantum gates, which make possible the implementation of all the other quantumgates by combinations.The second part of this thesis concerns the effects …

Mesure de la performance des agences bancaires par une approche DEA

2005

Using a DEA framework (Data Envelopment Analysis), we develop new performance indicators for integrated retail networks. A methodological discussion leads us to propose a productivity indicator which respects the criteria of controllability and transversal coherence. We then formalise the relationship between a performance indicator of a network's headquarters and the productivity of its various retailers. Finally, we combine these new indicators in crafting a management tool amenable to a system of balanced scorecards.