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.

Hybrid Active-Passive Damping Treatments Using Viscoelastic and Piezoelectric Materials: Review and Assessment

Abstract: Hybrid active-passive damping treatments combine the reliability, low cost and robustness of viscoelastic damping treatments and the high performance, modal selective and adaptive piezoelectric active control. Numerous hybrid damping treatments have been reported in the literature. They differ mainly by the relative positions of viscoelastic treatments, sensors and piezoelectric actuators. Therefore, the present article provides a review of the open literature concerning geometric configurations, modeling approaches and control algorithms for hybrid active (piezoelectric)-passive (viscoelastic) damping treatments of beams. In addition, using a unified finite element model able to represent sandwich damped beams with piezoelectric laminated faces and an optimal control algorithm, the geometric optimization of four hybrid treatments is studied through treatment length and viscoelastic material thickness parametric analyses. A comparison of the performances of these hybrid damping treatments is carried out a...

JASSA: a comprehensive tool for prediction of SUMOylation sites and SIMs

Abstract: MOTIVATION Post-translational modification by the Small Ubiquitin-like Modifier (SUMO) proteins, a process termed SUMOylation, is involved in many fundamental cellular processes. SUMO proteins are conjugated to a protein substrate, creating an interface for the recruitment of cofactors harboring SUMO-interacting motifs (SIMs). Mapping both SUMO-conjugation sites and SIMs is required to study the functional consequence of SUMOylation. To define the best candidate sites for experimental validation we designed JASSA, a Joint Analyzer of SUMOylation site and SIMs. RESULTS JASSA is a predictor that uses a scoring system based on a Position Frequency Matrix derived from the alignment of experimental SUMOylation sites or SIMs. Compared with existing web-tools, JASSA displays on par or better performances. Novel features were implemented towards a better evaluation of the prediction, including identification of database hits matching the query sequence and representation of candidate sites within the secondary structural elements and/or the 3D fold of the protein of interest, retrievable from deposited PDB files. AVAILABILITY AND IMPLEMENTATION JASSA is freely accessible at http://www.jassa.fr/. Website is implemented in PHP and MySQL, with all major browsers supported. CONTACT guillaume.beauclair@inserm.fr SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.

Supervisory control of discrete event systems based on structure theory of Petri nets

Abstract: The present work is related to the use of Petri nets structural techniques in the supervisory control of discrete event systems. A relevant property of the system behaviour under supervision is to be non-blocking, i.e. from any state reachable from initial state, it is always possible to reach a desirable (or marked) state. Recent works had shown that the synthesis of proper supervisors based on Petri net modelling of DES is an interesting approach. In this paper, we present a proper supervisor synthesis method based on a purely structural reasoning. This parametrized method is especially well-suited for a large class of discrete event systems, called G-Task, for modelling concurrent automated manufacturing systems with flexibility on routings and on synchronization patterns with shared resources. Also, it can be exploited for enforcing constraints on the reachability set of any bounded uncontrolled net.

Sparse Stabilization and Control of Alignment Models

Abstract: Starting with the seminal papers of Reynolds (1987), Vicsek et al. (1995), Cucker–Smale (2007), there has been a lot of recent works on models of self-alignment and consensus dynamics. Self-organization has so far been the main driving concept of this research direction. However, the evidence that in practice self-organization does not necessarily occur (for instance, the achievement of unanimous consensus in government decisions) leads to the natural question of whether it is possible to externally influence the dynamics in order to promote the formation of certain desired patterns. Once this fundamental question is posed, one is also faced with the issue of defining the best way of obtaining the result, seeking for the most "economical" way to achieve a certain outcome. Our paper precisely addressed the issue of finding the sparsest control strategy in order to lead us optimally towards a given outcome, in this case the achievement of a state where the group will be able by self-organization to reach an alignment consensus. As a consequence, we provide a mathematical justification to the general principle according to which "sparse is better": in order to achieve group consensus, a policy maker not allowed to predict future developments should decide to control with stronger action the fewest possible leaders rather than trying to act on more agents with minor strength. We then establish local and global sparse controllability properties to consensus. Finally, we analyze the sparsity of solutions of the finite time optimal control problem where the minimization criterion is a combination of the distance from consensus and of the l1-norm of the control. Such an optimization models the situation where the policy maker is actually allowed to observe future developments. We show that the lacunarity of sparsity is related to the codimension of certain manifolds in the space of cotangent vectors.