Conservatoire national des arts et métiers

About: Conservatoire national des arts et métiers is a education organization based out in Paris, France. It is known for research contribution in the topics: Population & Context (language use). The organization has 3573 authors who have published 7127 publications receiving 141430 citations. The organization is also known as: CNAM & Conservatoire des arts et métiers.

Challenges Facing PFC of a Single-Phase On-Board Charger for Electric Vehicles Based on a Current Source Active Rectifier Input Stage

Abstract: This paper aims to study the power factor (PF) correction scheme for a single-phase on-board charger of electric vehicles. The topology is based on a unidirectional current source active rectifier (CSAR) consisting of four insulated-gate bipolar transistors in series with four diodes followed by a boost converter. Buck-type rectifiers inject low-order input current harmonics into the ac mains. Thus, an inductor–capacitor ( LC ) input filter is employed. The capacitor's reactive energy results in a leading grid current. In order to achieve a unity displacement power factor, a phase shift control is implemented. However, the LC filter is prone to series and parallel resonances coming from the grid disturbances and the converter harmonics, respectively. Therefore, the phase shift control strategy combined with the topology of the CSAR results in a periodical resonance of the input filter. This phenomenon is studied in detail. In order to reduce the grid current's distortion level, an active damping control with resonance frequency tracking that achieves a good PF while meeting the IEC's international standards on harmonic current emissions is presented. An experimental test bench is developed to validate the simulations’ theoretical findings. Compliance with the standards is achieved and system limitations are discussed.

Digital phase-shifting grating shearography for experimental analysis of fabric composites under tension

Abstract: Digital phase-shifting grating shearography has been applied for the investigation of the tensile behaviour of carbon/epoxy plain-weave fabric composite with a small waviness. Experimental analyses were performed for the two following configurations: a single lamina and an iso-phase double laminate. The yarn crimp effects such as the tension/bending and tension/in-plane shear couplings were concentrated on the resin rich regions for the single lamina. In the latter case, the yarn crimp effects were still significant because although the transverse shear strain due to the local bending effect of yarns is a little constrained by the other neighboring layer, the degree of the constraint was certainly insufficient to degenerate the local bending effect.

Comparative evaluation of 3D virtual ligand screening methods: impact of the molecular alignment on enrichment.

Abstract: In the early stage of drug discovery programs, when the structure of a complex involving a target and a small molecule is available, structure-based virtual ligand screening methods are generally preferred. However, ligand-based strategies like shape-similarity search methods can also be applied. Shape-similarity search methods consist in exploring a pseudo-binding-site derived from the known small molecule used as a reference. Several of these methods use conformational sampling algorithms which are also shared by corresponding docking methods: for example Surflex-dock/Surflex-sim, FlexX/FlexS, ICM, and OMEGA-FRED/OMEGA-ROCS. Using 11 systems issued from the challenging “own” subsets of the Directory of Useful Decoys (DUD-own), we evaluated and compared the performance of the above-cited programs in terms of molecular alignment accuracy, enrichment in active compounds, and enrichment in different chemotypes (scaffold-hopping). Since molecular alignment is a crucial aspect of performance for the different...