Search results for "RECTIFICATION"

Du prononcé d'une sentence en rectification d'une erreur matérielle pendant l'instance du recours en annulation dirigé contre la sentence devant être…

2002

International audience; (Paris, 1re ch., sect. C, 18 oct. 2001, inédit, SA Cultur'Pom c/ SARL Grange du Moulin)

A pH-tunable nanofluidic diode: electrochemical rectification in a reconstituted single ion channel.

2006

We report pH-dependent electrochemical rectification in a protein ion channel (the bacterial porin OmpF) reconstituted on a planar phospholipid membrane. The measurements performed at single-channel level show that the electric current is controlled by the protein fixed charge and it can be tuned by adjusting the local pH. Under highly asymmetric pH conditions, the channel behaves like a liquid diode. Unlike other nanofluidic devices that display also asymmetric conductance, here the microscopic charge distribution of the system can be explored by using the available high-resolution (2.4 A) channel crystallographic structure. Continuum electrostatics calculations confirm the hypothesized bi…

The project scheduling polyhedron: Dimension, facets and lifting theorems

1993

Abstract The Project scheduling with resource constraints can be formulated as follows: given a graph G with node set N, a set H of directed arcs corresponding to precedence relations, and a set H′ of disjunctive arcs reflecting the resource incompatibilities, find among the subsets of H′ satisfying the resource constraints the set S that minimizes the longest path in graph (N, H ∪ S). We define the project scheduling polyhedron Qs as the convex hull of the feasible solutions. We investigate several classes of inequalities with respect to their facet-defining properties for the associated polyhedron. The dimension of Qs is calculated and several inequalities are shown to define facets. For …

A wideband THz Time Domain Spectroscopy table-top system based on ultrafast pulsed laser: Model and experiments

2014

We present an analytical model carefully describing the time-frequency behavior of all the stages composing our whole Terahertz Time Domain Spectroscopy laser based system, from the THz pulses generation via Optical Rectification, to their detection through Electro-Optic Sampling technique, by way of diffraction, collecting and focusing effects. In order to prove the effectiveness of our work, we report on the comparison among the experimental waveforms and the simulation results.

Wideband THz time domain spectroscopy based on optical rectification and electro-optic sampling

2013

We present an analytical model describing the full electromagnetic propagation in a THz time-domain spectroscopy (THz-TDS) system, from the THz pulses via Optical Rectification to the detection via Electro Optic-Sampling. While several investigations deal singularly with the many elements that constitute a THz-TDS, in our work we pay particular attention to the modelling of the time-frequency behaviour of all the stages which compose the experimental set-up. Therefore, our model considers the following main aspects: (i) pump beam focusing into the generation crystal; (ii) phase-matching inside both the generation and detection crystals; (iii) chromatic dispersion and absorption inside the c…

Modelling of wideband THz sources and detectors based on Optical Rectification and Electro-Optic Sampling

2012

5th EOS Topical Meeting on Optical Microsystems, Poster OμS13_1569798553: Analytical Model for wideband THz sources and detectors based on Optical Re…

2013

Analytical Model for wideband THz sources and detectors based on Optical Rectification and Electro-Optic Sampling

2013

An analytical model describing a laser based set-up for wideband THz generation and detection is presented. Particular attention is focused on the main broadband phenomena, which occur when THz radiations have to be handled.

On the design of observers robust to load variations for synchronous converters

2015

Due to the ever growing concern on energy efficiency issues, synchronous rectification gained increasing attention in recent years. In the semiconductor industry fast controllers developed for DC-DC converters are typically based on inductor current measures. In this context system costs and performances strictly depend on the current sensor and its proper design. In this paper we present a sensorless synchronous approach based on a current observer. The same observer formulation is valid for the three standard DC-DC converters, simplifying its design for different configurations. Furthermore the designed observers are proven to be robust against load variations, the most uncertain paramete…

Tetraalkylammonium Cations Conduction through a Single Nanofluidic Diode: Experimental and Theoretical Studies

2017

[EN] We describe experimentally and theoretically the concentration-dependent conduction of tetraalkylammonium (TAA+) cations through a nanofluidic diode fabricated in a polymer membrane via asymmetric track-etching techniques. This single-pore membrane exhibits current rectification characteristics because of the ionized carboxylate groups on the pore surface. We use aqueous solutions of potassium (K+ ), ammonium (A+ ), tetramethylammonium (TMA+ ), tetraethylammonium (TEA+ ), and tetrabutylammonium (TBA+ ) ions with concentrations ranging from 50 to 500 mM under acidic (pH 3.5) and physiological (pH 6.5) conditions. Compared with the K+ and A+ ions, the TMA+ , TEA+ , and TBA+ ions show rel…