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International audience; Design space exploration, that is an embodiment of a paradigm Design by Shopping, refers to the systematic activity of discovery and evaluation of the elements in the design space in order to identify optimal solution by reducing the design space toward an area of performance. This activity is composed of three main phases: the discovery, the optimization and the selection. There are existing tools for the design space exploration with different graphs (ScatterPlot matrix, 2D and 3D scatter plot, parallel coordinates plot, etc.). These graphs are useful for the representation of multidimensional set of data with an unlimited number of alternatives (design points). Obviously, during the selection phase, designers face to a reduced design space with a limited number of design points (in a performance area). Thus, in our work, we try to identify which graph is the most adapted to the selection phase. It emerges, from literature, three graphs useful for the representation of multidimensional set of data (>3 variables) and with a limited number of alternatives (

International audience

National audience; In many Wireless Sensor Network (WSN) applications, it is important to optimize the global energy efficiency to enhance both the node autonomy and the whole WSN lifetime. In this context, the achievement of a power-aware design is a complex task due to the impact over the WSN energy consumption of different parameters, which are inherent to application, network or node levels. Therefore, a cross-level energy model is a useful way to estimate this energy consumption, leading designers to take correct decisions at the earliest design stages. Thus, this paper describes the principles of a cross-level energy model, which tries to address some weakness of existing WSN simulators in terms of energy modelling.

Most of the time, starting new design projects based on innovative product concepts is a strategic but complicated process. Individual initiatives and the development of new ideas take place within conflicting contexts combining technical, economical and social aspects. During theses phases actors have to formalize new ideas, to exchange them and to collaborate to promote them. Traditional tools do not support such activities. We propose in this paper a new approach dedicated to the product development process from the early phases to the embodiment design phases. Metamodeling techniques and new tools (ID2 - Innovation Development and Diffusion - and CE - Constraint Explorer -) are proposed in order to support those phases ensuring the collaboration and the interaction between design actors, the knowledge and information management, the development of innovative ideas, and the improvement of embodiment design solutions. More over we propose to link our tools to a PLM environment to improve the sharing and the management of information, documents and design solutions in order to foster collaboration. The main objective of our implementation is to foster innovation during design process by improving sharing and reuse of innovative ideas and allowing the organization to identify rapidly best consensus for design solutions.Copyright © 2004 by ASME

ISBN: 978-1-61208-744-3; International audience; In the design stage, Wireless Sensor Network developers generally need simulation tools to save both time and costs. These simulators require accurate models to precisely describe the network components and behaviours, such as energy consumption. Nevertheless, although the model has grown in complexity over last years, from layered-stack to cross-level, the energy aspects are not yet well implemented. In this paper, we suggest an energy-aware cross-level model for Wireless Sensor Networks. Our modelling approach allows for parameters that belong to different levels to interact with each other and to analyse their impact on energy consumption. To validate this approach, the energy-aware cross-level model for network radiofrequency activities is first provided. The results obtained using suggested scenarios are compared with those collected from a well-known simulator: NS2. Finally, the usefulness of our model in Wireless Sensor Network design process is demonstrated thanks to a case study aimed at comparing and selecting the most energy-efficient wireless link protocol.

International audience; Cet article présente une modélisation numérique 3D de l’aérodynamique interne d’un moteur 2 temps durant la phase de balayage. Cette modélisation est ensuite confrontée à des essais en soufflerie grâce à une maquette à l’échelle 1 du cylindre moteur pour 2 positions du piston et plusieurs conditions de pression en amont. L’approche RANS associée au modèle de turbulence k-e realizable fournit des résultats numériques proches de ceux obtenus de manière expérimentale, avec des écarts inférieurs à 5% pour le débit massique.

ISBN : 2-9515730-9-X; International audience; T.A.C system was built in order to propose a new mode of remote communication. When somebody needs to be assisted on a manual task, classical technical support methods such as phone or visioconference rapidly show their limits in terms of human interaction. By allowing a distant expert to see exactly what an operator is seeing, he could interact with him in interactive time thanks to augmented reality via an adequate interaction paradigm named "Picking Outlining Adding". By "simulating" co-presence of the expert close to the operator through visual guidance information, ambiguity of language and difficulty of communication are avoided, and operations are easily performed. Scientific experimentation we have conducted and we describe in this article shows the teaching interest and the efficiency of this new mode of communication. The operator learns and operates more rapidly, in complete serenity, increasing reliability of his tasks. Moreover, throughout this paper, we show that the developed principles are sufficiently general to be applied to other use cases of tele-assistance that go beyond the originally planned industrial maintenance.

International audience; This paper considers the configuration of physical systems in a business to business environment (machine tool, aerospace equipment, cranes ...). In this kind of business, knowledge-based configuration software are frequently used when dealing with Assemble/Make-To-Order or (Configure-To-Order (CTO)) situations where the entire customer’s requirements can be fulfilled with standard systems. However, in Engineer-To-Order (ETO) situations where non-standard systems must be designed in order to fulfill the entire customers’ requirements, existing knowledge-based configuration software cannot be used. In fact, the configuration hypothesis state that all configured systems are assembled from standard sub-systems and components. The aim of this paper is therefore to investigate how the existing products/systems configuration hypothesis, problems’ definitions, and models can be modified or adapted in order to allow the use of configuration software in ETO situations. In this purpose, first, the main differences between standard and non-standard systems are analyzed. Then, six cases of systems configuration that differentiate CTO from ETO are identified and discussed. Finally, some Constraint Satisfaction Problems (CSP) based modeling extensions are proposed to allow the use of configuration software in these situations.

Le congrès a pour titre "L'essor des systèmes connectés dans l'industrie et les services"; International audience; Cette communication s’intéresse à l’ingénierie des risques lors de la définition des processus de réalisation d’offres en relation client-fournisseur. Nous nous situons dans le cas où lors de la remise de l’offre au client, celle-ci n’est pas basée sur une conception détaillée du produit/système à fournir mais seulement sur une connaissance des principes à mettre en oeuvre. Il y a prise de risque car lorsque le client accepte l’offre, le fournisseurdoit finaliser (i) la conception du produit/système objet de l’offre ainsi que (ii) son processus de mise à disposition.L’ingénierie de ce type de risque est le plus souvent effectuée manuellement par des experts. L’objectif de cette communication est de définir et discuter des éléments d’un système à base de connaissances permettant d’assister cette ingénierie. La problématique est d’abord détaillée, un modèle de connaissances proposé et des possibilités d’exploitation discutées.

The eXtensible Markup Language (XML) has become the main standard for Web information representation and data exchange over the last decades. However, XML documents present high heterogeneity regarding their structure. Hence, there is still a need of new approaches to manage and recognize similar information that consider the content and the semantic, besides the document structure. Most current approaches semantically analyze the XML document content, regardless its structure or vice versa. In this paper, we propose LSI*, a new approach for XML documents similarity by integrating in the semantic analysis their structural composition. We extend the Latent Semantic Indexing (LSI), which is based on Singular Value Decomposition (SVD), by considering the term itself and the context (i.e., structural path) in which it appears, to determine the semantic similarity between XML documents. To evaluate the performance of our proposal, we perform experiments to compare LSI* to state-of-the-art methods based on structural and content-structural analysis. Results show a precision up to 71, 43% when the XML structure is considered in the content analysis.

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International audience; Automated fibre placement (AFP) is an incipient manufacturing process for composite structures. Despite its conceptual simplicity it involves many complexities related to the necessity of melting the thermoplastic at the interface tape-substrate, ensuring the consolidation that needs the diffusion of molecules and control the residual stresses installation responsible of the residual deformations of the formed parts. The optimisation of the process and the determination of the process window requires a plethora of simulations because there are many parameters involved in the characterization of the material and the process. The exploration of the design space cannot be envisaged by using standard simulation techniques. In this paper we propose the off-line calculation of rich parametric solutions that can be then explored on-line in real time in order to perform inverse analysis, process optimisation or on-line simulation-based control. In particular, in the present work, and in continuity with our former works, we consider two main extra-parameters, the first related to the line acceleration and the second to the number of plies laid-up.

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International audience; A micro-grid is a weak electrical grid, which can be easily subject to disturbances because it includes a variety of intermittent power sources, single-phase, three-phase and nonlinear loads, which can have a dynamic impact on power quality. The unbalance and the harmonic components in current and voltage waveforms are the most important among these. In this paper, the topologies and the control strategy of two Active Power Conditioners (APC) have been investigated in order to improve the operation of a micro-grid. The APC topologies presented in this paper act as an interface between renewable energy sources and the AC bus of a micro-grid. They also use an improved control strategy, which makes possible to inject energy in the micro-grid, compensate the current harmonics and correct the power factor. Moreover, the proposed control strategy allows the line current at the point of common coupling (PCC) to be balanced and sinusoidal even when the load is unbalanced. Consequently, the voltage at the PPC becomes balanced. The validity of the innovative control strategy has been proved in simulation using Matlab/Simulink environment.

International audience; In this paper we propose a new approximation technique within the context of meshless methods able to reproduce functions with discontinuous derivatives. This approach involves some concepts of the reproducing kernel particle method (RKPM), which have been extended in order to reproduce functions with discon-tinuous derivatives. This strategy will be referred as Enriched Reproducing Kernel Particle Approximation (E-RKPA). The accuracy of the proposed technique will be compared with standard RKP approximations (which only reproduces polynomials).

International audience; This paper discusses a hybrid wind diesel system aims to validate wind powered section of the experimental system. The experimental system proposed consists of a wind turbine simulator, a permanent magnets generator, a diode bridge rectifier, a step down converter, a bank of battery, a load and a control unit. An other operation of three-phase, four-wire voltage source inverter (VSI) under unbalanced voltage conditions is also investigated.

Selective Laser Melting offers new perspectives in terms of part design and simplification of complex assemblies. However, because such a process is based on the fusion of the material, severe thermo-mechanical conditions arise and are responsible for local plastic deformation, residual stresses and distortion of the manufactured component. Mastering distortion is of major interest in the search for a robust and repeatable industrial process. The lack of experimental knowledge and the high cost associated to a trial and error approach makes it difficult to anticipate distortion relying only on empirical rules. Numerical simulation is therefore an interesting answer both for process understanding thanks to high fidelity models and for process estimation thanks to lighter models. Inherent strain method is part of the latter category of models and proves to be interesting for estimating distortion at a macroscopic level. Experimental calibration of inherent strain induced by the process is a way to get rid of uncertainties associated to a complex thermo-elasto-plastic numerical model. Nevertheless, such an approach requires a reverse analysis in order to identify the inherent strain responsible for the measured elastic springback. This paper proposes a method for a fast reverse identification of inherent strain thanks to the offline generation of a numerical abacus. A model reduction technique called Proper Generalized Decomposition is implemented for the construction of this abacus.

International audience; In the design stage, Wireless Sensor Network developers generally need simulation tools to save time and money. These simulators require accurate models to precisely describe the behaviors of network nodes. Nevertheless, although model complexity has grown from layered-stack to cross-level, the energy aspects are not yet well implemented. In this paper, we suggest an energy-aware cross-level model for Wireless Sensor Network. Our modelling approach allows parameters that belong to different levels to interact and affect each other. This approach is used to predict the nodes energy consumption and to estimate the lifetime of the system. First, the results obtained from the implementation of our approach will be compared with those collected from a well-known simulator, Network Simulator version 2 using a set of basic scenarios. Then, the utility of our approach in the Wireless Sensor Network design process is highlighted using detailed scenarios that cover different types of interactions.