Ecole Polytechnique - Palaiseau

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Palaiseau, France

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Patent
Ecole Polytechnique - Palaiseau and French National Center for Scientific Research | Date: 2015-04-14

A device for forming a quasi-neutral ion-electron beam, including: a chamber; a set of means for forming an ion-electron plasma in the chamber; and means for extracting and accelerating charged particles from the plasma out of the chamber. The particles are capable of forming the beam and the extraction and acceleration means that include a set of at least two grids located at one end of the chamber.


Patent
CNR Institute of Neuroscience and Ecole Polytechnique - Palaiseau | Date: 2015-02-18

According to one aspect, the invention relates to a device (100) for remote polarimetric characterisation of a sample (S). It comprises a source (10) for emitting at least one incident light wave at at least one first wavelength (_(E)); a monomode optical fibre (30) in which the incident light wave is intended to propagate; a polarisation state generator (PSG) arranged on the proximal side of the optical fibre; a reflector (40) intended to be arranged on the distal side of the optical fibre; a polarisation state analyser (PSA) arranged on the proximal side of the optical fibre and allowing, for each probe state of the incident wave generated by the polarisation state generator, the polarisation of the light wave obtained after propagation of the incident wave in the optical fibre (30), reflection from the distal side of the optical fibre and reverse propagation in the optical fibre (30), to be analysed. Processing means (70) make it possible to determine, from a first polarimetric characterisation of the optical fibre, a Mueller matrix (M_(F)) associated with the optical fibre, and, from a second polarimetric characterisation of the assembly comprising the optical fibre and the sample, a Mueller matrix (M_(T)) associated with said assembly. The Mueller matrix (M_(o)) associated with the sample is determined from the Mueller matrices associated with the optical fibre and the assembly comprising the optical fibre and the sample, respectively.


Patent
Ecole Polytechnique - Palaiseau and French National Center for Scientific Research | Date: 2017-03-29

The invention relates to a device (100) for forming a quasi-neutral ion-electron beam, comprising: a chamber (20); a set of means (31, 30, 40, 58) for forming an ion-electron plasma in the chamber (20); a means (50) for extracting and accelerating charged particles from the plasma out of the chamber (20), said particles being capable of forming the beam and the extraction and acceleration means (50) comprising a set of at least two grids (51, 54) located at one end of the chamber; a radio-frequency alternating voltage source (52) adapted to generate a signal having a radio-frequency of between the plasma frequency of the ions and the plasma frequency of the electrons, the radio-frequency voltage source (52) being disposed in series with a capacitor (53) and being connected, at one of its outputs and by means of the capacitor (53), to at least one of the grids of the set of at least two grids (51, 54), at least one other grid of the set of at least two grids (51, 54) being either set to a reference potential or connected to the other output of the radio-frequency voltage source (52).


Patent
Ecole Polytechnique - Palaiseau and French National Center for Scientific Research | Date: 2017-05-03

The invention relates to a device (10) for recovering energy from a fluid flow, comprising a flag (12), capable of being deformed under the effect of the fluid flow (F1), and an oscillator device (14) comprising an oscillating mast (16), to which the flag (12) is attached. The invention also relates to applications of such an energy recovery device to create an electric current or in systems for measurement and/or regulation of the speed and/or flow rate of a fluid.


Patent
Consejo Superior De Investigaciones Cientificas and Ecole Polytechnique - Palaiseau | Date: 2015-03-27

An acquisition device (20) comprising a wall and a transducer (23) constituted by a body (24, 324) on which electrodes (25) are fastened spaced apart from one another. An electrical impedance (R) of the transducer is variable as a function of deformation of the transducer. When looking in a direction perpendicular to a surface (36) of the wall, at least two electrodes (25) of said plurality of electrodes are spaced apart from each other. The transducer is incorporated under the surface (36) of the wall.


Patent
Ecole Polytechnique - Palaiseau | Date: 2017-03-08

A method for generating an ion flux asymmetry in a capacitively coupled radiofrequency plasma reactor (4) comprises a step of exciting a first electrode (24) with a radiofrequency voltage waveform. The normalized voltage waveform is a waveform approximated, with a degree of approximation, by a normalized sawtooth wave radiofrequency function having different up and down slopes. The degree of approximation of the approximate waveform and the pressure P of the gas (6) are sufficiently high to cause an ion flux asymmetry to appear between the ion flux at the first electrode and the ion flux at a second electrode (26).


Patent
Ecole Polytechnique - Palaiseau | Date: 2017-02-08

The invention relates to an acquisition device (20) comprising a wall and a transducer (23) consisting of a body (24, 324) to which electrodes are attached at a distance from each other. An electrical impedance (R) of the transducer is variable according to the deformations of same. Looking along a direction perpendicular to a surface (36) of the wall, at least two electrodes (25) of said plurality of electrodes are separate from each other. The transducer is built into the wall, beneath the surface (36) thereof.


Patent
French National Center for Scientific Research and Ecole Polytechnique - Palaiseau | Date: 2017-01-25

According to one aspect, the invention relates to a device (100) for remote polarimetric characterisation of a sample (S). It comprises a source (10) for emitting at least one incident light wave at at least one first wavelength (); a monomode optical fibre (30) in which the incident light wave is intended to propagate; a polarisation state generator (PSG) arranged on the proximal side of the optical fibre; a reflector (40) intended to be arranged on the distal side of the optical fibre; a polarisation state analyser (PSA) arranged on the proximal side of the optical fibre and allowing, for each probe state of the incident wave generated by the polarisation state generator, the polarisation of the light wave obtained after propagation of the incident wave in the optical fibre (30), reflection from the distal side of the optical fibre and reverse propagation in the optical fibre (30), to be analysed. Processing means (70) make it possible to determine, from a first polarimetric characterisation of the optical fibre, a Mueller matrix (MF) associated with the optical fibre, and, from a second polarimetric characterisation of the assembly comprising the optical fibre and the sample, a Mueller matrix (T) associated with said assembly. The Mueller matrix (o) associated with the sample is determined from the Mueller matrices associated with the optical fibre and the assembly comprising the optical fibre and the sample, respectively.


Patent
French National Center for Scientific Research and Ecole Polytechnique - Palaiseau | Date: 2017-08-09

The invention relates to a medical device (12) comprising an electrical measurement circuit (16), in which are connected at least two sensors (22) with variable impedance according to a physical magnitude detected, an electric energy source (18) for powering the electric measurement circuit (16), an antenna (18) for emitting an electromagnetic field in accordance with the impedance of the electrical measurement circuit (16), each of the sensors (22) being associated with a switch (24) so as to short-circuit the sensor (22) in said measurement circuit (16), the medical device (12) also including a system (26) for controlling the switches (24) in order consecutively to control the opening or the closing of the switches (24), according to predetermined configurations. In particular, the medical device (12) can be used on the human body or implanted in the human body.


Morlon H.,Ecole Polytechnique - Palaiseau
Ecology Letters | Year: 2014

Estimating rates of speciation and extinction, and understanding how and why they vary over evolutionary time, geographical space and species groups, is a key to understanding how ecological and evolutionary processes generate biological diversity. Such inferences will increasingly benefit from phylogenetic approaches given the ever-accelerating rates of genetic sequencing. In the last few years, models designed to understand diversification from phylogenetic data have advanced significantly. Here, I review these approaches and what they have revealed about diversification in the natural world. I focus on key distinctions between different models, and I clarify the conclusions that can be drawn from each model. I identify promising areas for future research. A major challenge ahead is to develop models that more explicitly take into account ecology, in particular the interaction of species with each other and with their environment. This will not only improve our understanding of diversification; it will also present a new perspective to the use of phylogenies in community ecology, the science of interaction networks and conservation biology, and might shift the current focus in ecology on equilibrium biodiversity theories to non-equilibrium theories recognising the crucial role of history. © 2014 John Wiley & Sons Ltd/CNRS.

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