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National audience; Real-time adaptive production control in the flexible manufacturing cell (FMC) is a complex issue that needs to be addressed to realize good performance and high productivity. In this paper, we have considered a support vector machine (SVM)-based simulation approach to resolve a production control problem in an FMC that operates in a dynamic environment. A SVM-based simulation approach chooses the most relevant scheduling rule out of several predefined ones on the basis of the current states of the system. This paper examines and compares the performance of the SVM-based simulation approach with the competent scheduling rules under two different operational environments which are characterized by the uncertainty of demand. We have also developed a Visual Basic-based simulation approach for scheduling of component parts in the context of FMC under different situations. The SVM methodology to control the production offers better performance than the single-rule-based production control system.

International audience; Multiple-Input/Multiple-Output (MIMO) techniques have recently become an important research field for enhancing the performance of in-home Power Line Communication (PLC) systems by exploiting the additional Protective Earth wire. The development of such systems requires an accurate description of the channel noise. In this paper we have presented a model for PLC background noise based on an extensive set of measurements. We have adopted the framework of multivariate time series to model the PLC background noise.This paper employs the Vector Autoregressive (VAR) modeling technique to extract noise model parameters from the measured noise. We have verified the accuracy of the noise model by comparing time and frequency domain correlation of measured and modeled noises.

International audience; This paper deals with a tunable bandpass filter topology which controls independently and simultaneously both the central frequency and bandwidth. This tunable filter results from the association of MEMS cantilevers, used as variable capacitors, with an original passive topology. The latter is based on dual behavior resonators (DBRs), each of them is constituted of low- and high-frequency open-ended stubs. The associated filter electrical response is characterized by tunable frequency transmission zeros. A millimeter bandpass filter with central frequency and relative bandwidth tunability of about 10 and 75%, respectively, is presented.; This paper deals with a tunable bandpass filter topology which controls independently and simultaneously both the central frequency and bandwidth. This tunable filter results from the association of MEMS cantilevers, used as variable capacitors, with an original passive topology. The latter is based on dual behavior resonators (DBRs), each of them is constituted of low- and high-frequency open-ended stubs. The associated filter electrical response is characterized by tunable frequency transmission zeros. A millimeter bandpass filter with central frequency and relative bandwidth tunability of about 10 and 75%, respectively, is presented.

International audience; In this paper we discuss about various modifications of classical coupled-lines narrow bandpass filter to obtain some frequency response improvement. The first modification concerns the broadening of the resonator strip-widths to improve their unloaded Q-factor. The second modification consists in replacing the in/out coupled lines section by tapped lines feeding. Finally a transmission zero is added using a geometrical modification that favor coupling between non-adjacent resonators. The theoretical investigation is carried out through a DOE based sensitivity study using both a circuit modeling approach and a full wave analysis. Theoretical and experimental results on microstrip filters are compared.; In this paper we discuss about various modifications of classical coupled-lines narrow bandpass filter to obtain some frequency response improvement. The first modification concerns the broadening of the resonator strip-widths to improve their unloaded Q-factor. The second modification consists in replacing the in/out coupled lines section by tapped lines feeding. Finally a transmission zero is added using a geometrical modification that favor coupling between non-adjacent resonators. The theoretical investigation is carried out through a DOE based sensitivity study using both a circuit modeling approach and a full wave analysis. Theoretical and experimental results on microstrip filters are compared.

International audience; An original implementation of a TX/RX transceiver for future UMTS base stations is proposed in this paper. Machined Foam substrates are stacked at first for implementing a square patch antenna on a composite thick support, then delivering interesting performances in terms of bandwidth and efficiency with respect to planar solutions. Active and passive devices are inserted within a shielded cavity created under the patch, then preventing from size constraints at such frequencies as well as insertion loss and parasitic radiations. A complete experimental procedure is presented for both TX and RX operating modes.; An original implementation of a TX/RX transceiver for future UMTS base stations is proposed in this paper. Machined Foam substrates are stacked at first for implementing a square patch antenna on a composite thick support, then delivering interesting performances in terms of bandwidth and efficiency with respect to planar solutions. Active and passive devices are inserted within a shielded cavity created under the patch, then preventing from size constraints at such frequencies as well as insertion loss and parasitic radiations. A complete experimental procedure is presented for both TX and RX operating modes.

International audience; This paper deals about the design and the implementation of a very compact microstrip Tx/Rx diplexer for future UMTS mobile terminals. Miniaturized loop-resonators filters have been developed and combined INTO data_ds.tmp_pub_a diplexer structure, satisfying different constraints such as a high electrical performance level (especially, a very narrow bandwidth, low insertion losses and a high out-of-band rejection), or also a great compactness and a compatibility with a standard planar integration.; This paper deals about the design and the implementation of a very compact microstrip Tx/Rx diplexer for future UMTS mobile terminals. Miniaturized loop-resonators filters have been developed and combined INTO data_ds.tmp_pub_a diplexer structure, satisfying different constraints such as a high electrical performance level (especially, a very narrow bandwidth, low insertion losses and a high out-of-band rejection), or also a great compactness and a compatibility with a standard planar integration.

International audience; In this paper, we discuss the control and suppression of spurious resonances commonly encountered with distributed bandpass filters. The basic idea consists of introducinglow-pass structures within bandpass topologies. By adjusting low-pass filter cutoff frequencies, harmonic resonances are attenuated, while maintaining in-band performances. In addition, transmission losses may be reduced as the insertion technique leads to optimum designs in terms of overall size. The approach described here is based upon the combination of classical synthesis techniques and optimization proceduresprovided by conventional computer-aided-design tools. Experimental results are obtained in the case of /spl lambda//sub g//4 shunt-stub filters implemented in classical semilumped low-pass architectures. Then, we investigate alternative integration technologies and techniques to improve the out-of-band rejection over very wide operating bandwidth. To overcome some design limitations, i.e., workable characteristicimpedance value, we propose and validate a multilayer solution. Finally, new low-pass topologies are suggested to improve low-pass filter band rejection.; In this paper, we discuss the control and suppression of spurious resonances commonly encountered with distributed bandpass filters. The basic idea consists of introducinglow-pass structures within bandpass topologies. By adjusting low-pass filter cutoff frequencies, harmonic resonances are attenuated, while maintaining in-band performances. In addition, transmission losses may be reduced as the insertion technique leads to optimum designs in terms of overall size. The approach described here is based upon the combination of classical synthesis techniques and optimization proceduresprovided by conventional computer-aided-design tools. Experimental results are obtained in the case of /spl lambda//sub g//4 shunt-stub filters implemented in classical semilumped low-pass architectures. Then, we investigate alternative integration technologies and techniques to improve the out-of-band rejection over very wide operating bandwidth. To overcome some design limitations, i.e., workable characteristicimpedance value, we propose and validate a multilayer solution. Finally, new low-pass topologies are suggested to improve low-pass filter band rejection.

International audience; This paper deals with linking system-level design tools with existing hardware design and synthesis tools. The main difficulty is the gap that exists between concepts handled at the system level and concepts accepted by existing synthesis tools. The paper gives an overview of the state of the art and presents COSMOS, a design methodology intended to fill this gap. The methodology allows the combination of a system-level design language (SDL) and a hardware design language (VHDL). The use of such a system-level specification can dramatically reduce the volume of information handled.

International audience; In order to face the continuous increase of the data traffic on cellular networks, using WiFi to offload the LTE network can be an interesting solution for the operators. The convergence between fixed and mobile access allows the WiFi access points to be connected to the cellular eNodeBs. This is known as very tight coupling between LTE and WiFi. WiFi and LTE flows are merged just bellow the IP layer which allows faster attachment procedures to WiFi access points and dual WiFi/LTE transmission while providing a seamless experience to the end user. However, WiFi networks are very different from LTE in terms of delays and loss rates which may have a bad impact on higher layers such as TCP. In this paper, we study the performance of TCP with Very Tight Coupling. We perform experimentation on a real testbed based on the Open Air Interface framework.

International audience; Noncooperative underwater acoustic (UWA) communication systems are prone to interfere with each other since the limited resource offered by the channel is not regulated by any standard. Mutual inteferences can significantly degrade the performances of such systems and it is necessary to find policies allowing UWA devices to access the same physical resource. In this paper, we consider noncooperative UWA OFDM systems competing to access the same portion of the spectrum. We show that an efficient decentralized power allocation strategy can be achieved when all the communication links apply a waterfilling policy only based on little knowledge about their environment. Numerical simulations performed with real UWA channels sounded at-sea demonstrate the relevance of our approach.

International audience; In the context of future seabed underwater scientific observatories, a new Wi-Fi antenna (at 2.45 GHz) was recently developed for high data rate and short range wireless underwater applications. It supports real time video and rapid large file transmissions (54 Mb/s during experiments). Also its simplicity and compatibility with standard Wi-Fi equipment (modems, etc.) makes it a low cost solution for underwater applications. Therefore, while first prototypes have ever experimentally demonstrated the capabilities of the developed solution, several optimizations are possible. This paper focuses on size reduction and improvement to sea pressure resistance, bandwidth broadening, and a new antenna excitation which notably enable further height reduction.

National audience; Multi-touch interaction requires a trade-off between users' desires and capabilities, and gesture recognition constraints. Current approaches to that problem lack flexibility. The number of fingers used for a gesture usually plays a key part in the recognition process, for example. In this paper, we propose the use of pseudo-rigid movements to increase the flexibility of this process. We show how these movements can be determined in real time from the contact information usually available. We explain how they allow to free the recognition process from the number of fingers used and to move towards multi movement gestures, independent or coordinated. Finally, we present an interaction technique that takes advantage of this increased flexibility.

In this paper, a study of an autonomous hybrid PV-Wind-battery system for a residential house of 4 persons in La Rochelle in France is presented. It includes system design optimization and performance evaluation in addition of its economic and environmental life cycle analysis. The results show a low environmental impact and a reasonable economic cost of the system.

LGEP 2011 ID = 876; International audience; In order to find better solution for the development of Electric Vehicles (EVs), many research are performed by companies, universities and research laboratories. The main goal of these works is to provide some solutions to reduce the cost, increase the compactness, improve the autonomy and the reliability as well as the vehicle energetic efficiency and last but not least, reduce the global carbon emissions impact of the vehicle. This paper deals with an on-board battery charger for EVs or PHEVs where power electronics are reduced thanks to the use of same power converters in traction and charger mode. RST controllers in discrete time are design to control the PWM rectifier for the single-phase case.

National audience; In Human-Computer Interaction, plasticity refers to the capacity of User Interfaces (UI) to adapt to the context of use (user, platform, environment) while preserving user-centered properties. Until now, plasticity was the scope of various studies. The adaptation from a context of use to another was studied in order to satisfy the end-user's requirements. This paper changes the focus: plasticity in itself is not the scope anymore; it is viewed as a way for designers to improve UI quality. The iterative design process is detailed for a case study where all design decisions have been recorded in terms of their influence on UI ergonomic quality. The case study deals with e-goverrment procedures. The return of experience shows that paying attention to plasticity for a small screen platform results in improvements on the large screen platform version due to the reexamination of its initial design; En Interaction Homme-Machine, la plasticité désigne la capacité des Interfaces Homme-Machine (IHM) à s'adapter aux variations du contexte d'usage (utilisateur, plate-forme, environnement) en conservant la qualité attendue par l'utilisateur. La plasticité a fait l'objet de nombreuses études ; l'adaptation d'un contexte d'usage à un autre y était envisagée dans le but de satisfaire l'utilisateur final. Dans cet article, la perspective est différente : la plasticité n'est plus l'objet de l'étude mais un moyen pour le concepteur d'améliorer la qualité des IHM. L'étude de cas présentée dans cet article est la conception d'une téléprocédure citoyenne plastique. Nous relatons tous les choix de conception et étudions leur impact sur la qualité des IHM. En particulier, nous montrons que concevoir une IHM pour un petit écran permet d'améliorer la qualité d'une version grand écran conçue au préalable.

International audience; Cognitive assistance systems are aimed to support people loosing their autonomy while completing activities of daily living (ADL). The range of activities to support, the dissemination of interactive devices in the environment and the variability of users' cognitive capacities raise real challenges when designing assistance in such systems. This paper addresses the assistance issues and presents guidelines for assistive systems design. Especially, based on an experiment of the assistance provided while completing ADL, we suggest a principle of scaled assistance. The principle was applied to Archipel, a cognitive orthesis. This application and the results analysis of a 12 sujects experiment led to the evaluation and the improvement of some ergonomic guidelines about ambient assisted living

The Partial Element Equivalent Circuit method (PEEC) is well suited to the extraction of the conducted electromagnetic (EM) disturbance parameters in the electronic wiring systems. It can be an efficient tool for the EMC study relevant to automotive cables. However, the complete EMC analysis of embedded systems requires also reliable models for the radiated emissions especially at high frequencies. In this paper, an efficient approach based on the PEEC method is developed for the modeling of the cable radiations.

National audience; The development of micro and nanotechnologies requires the design of microrobots and Microsystems able to handle submillimetric objects. Many micromanipulation systems have been built. However, improvement of the performances requires the use of advanced control methods. In this paper, we present the main characteristics of the microworld from a control point of view and some control strategies adapted to the microsystems.

This paper describes the design and the placement of piezoelectric actuators on switched reluctance motors by means of a genetic algorithm (nondominated sorting genetic algorithm II) for the purpose of reducing stator vibrations. Two distinct approaches are presented: one energy-related and the other based on a minimization of the resultant displacement. These methods lead to design and placement strategy for the piezoelectric actuators. A number of optimal actuators obtained using these kinds of approaches is also compared with mechanical finite-element simulations. At last, a solution is achieved in order to validate optimal placement using positive position feedback active filtering.

This paper presents an original design option dedicated to output-filtered pulsewidth modulation inverters used in uninterruptible power systems, embedded networks, or motor drives operating on long cables. It is based on the coupling of interleaved inverter cells by means of intercell transformers (ICTs) and is characterized by very good dynamic behavior on load transients, which is an important issue in such applications. ICT solutions are compared with the classical interleaved solutions using separate inductors. A specific design method is developed to achieve this comparison based on toroidal core shapes. The results obtained with a 600 V, 7.5 kW inverter show the usefulness of ICT-based designs, especially when nanocrystalline magnetic material is used; high specific power and very good dynamic performances are obtained.

cote interne IRCAM: Noisternig08a; None / None; National audience; Auralization is the process of making audible the acoustics of complex virtual architectural spaces in a realistic and accurate manner. This paper presents a novel real-time auralization software environment comprising a room acoustic modeler, a spatial renderer for auralization, and a visualization and scene graph unit for interactivity. The computation of early reflection paths within the geometric model is based on an efficient beam tracing algorithm capable of real-time detection of specular reflection paths in a static geometry with one or several moving listener(s). For “simple" rooms, the real-time performance is maintained even with dynamic geometries and sources. Results of the room acoustic model consisting of visible reflection paths and their accumulated material attenuation are sent to the audio renderer. From this geometrical and acoustical data, listener position-relative 3D room impulse responses are generated using a hierarchical-order Ambisonics approach. Finally, the spatialized audio output is presented to the listener via multiple loudspeakers or binaurally rendered over headphones. As higher order reflections are more diffuse in nature, they are encoded using lower Ambisonic orders, thereby reducing computational load. The environment combines high quality audio with visual rendering realized using the open source platforms Pure Data and VirChor respectively. This open source auralization framework provides direct audio-visual interaction in real-time and is suitable for VR environments.

International audience; In this paper, we consider MAC (media access control) protocols appropriate to the underwater acoustic networks. First, we consider a media access method based on the Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) protocol used in the wireless local area networks IEEE 802.11 (WiFi). In the underwater acoustic channel, the acoustic wave propagates very slowly with regard to the electromagnetic wave (about 1500 m s ). Therefore the propagation delay is significant and thus collisions present a high cost considering the delay of transmission and the available throughput. To avoid this problem, we consider a second protocol in which we integrate a WAIT command [1]. Finally we integrate to our proposition a power control mechanism in order to increase network performance (delay, throughput). The performance evaluation of the three propositions has been done in terms of available throughput of the underwater sensors, delay of transmission and collision probability. The proposed simulation system model is detailed.

This paper presents a virtual reality environment for the design and simulation of transitic systems. This framework is called SimSED (Simulation of Discrete Event Systems). The objective is to test and validate the control code of the system before on-site implementation. The control code is validated by joint simulation of the transitic system's material part and control part. The system is validated according with a set ofscenarii. The virtual reality environment provides a tool for representing a transitic system in three dimensions, which encapsulates the dynamic behavior of the system. The applications developed by using this framework are also presented.

The air-handling units (AHUs) provide complete control of temperature and humidity in air-conditioned spaces. The models of the AHU elements are nonlinear and the controlled variables, temperature and relative humidity, coupled. This paper demonstrates that in the case of sensible heat exchange without moisture removal if the outputs of the electric coils, fluid-filled coils and steam humidifiers of an AHU are considered to be the differences between the air temperature and the humidity ratio of the outlet and the inlet, then the models may be written as the product of a static and a dynamic gain. The parameters of the discrete form of these models are experimentally identified. The dynamics of the elements and of their sensors are very similar. Therefore, the parameter identification of the elements takes into account the model of the sensor, previously identified. This grey-box approach combines theoretical modelling, parameter identification of discrete models and parameter identification of partially known models by using optimization techniques.

The design of innovative heating, ventilating and air-conditioning systems for energy saver buildings relies on fast and robust computer softwares able to predict the details in space and time of the indoor environment. In this paper we show the interest of having in one hand, an open and flexible environment to develop and test new models, and on the other hand, a fast simulation tool that integrates satisfactory models to quickly assess the indoor environment quality. Both tools implements a simulation method called the zonal method that is intermediate between single-node models and computational fluid dynamics models. These tools are then applied to analyze the details of the indoor environment in a cavity under mixed convection conditions, to evaluate the thermal coupling between an electric heater and the ambiance and finally to realize a whole year thermal comfort analysis within a dwelling cell.

International audience; In this paper, the furtivity of acoustic signals commonly used in oceanic acoustic tomography experiments is addressed. Three kinds of detectors are presented that can be used by an outsider to detect either unknown signals or signals showing the main characteristics of common tomographic signals. In the first case, the detector decision statistic is based on the signals energy, whereas in the second case it exploits either cyclostationarity properties of the signals or their time-frequency characteristics. Performance of these detectors on signals transmitted through a multipath underwater channel is studied.

In order to characterize the timing, mode and size of a possible lower head failure (LHF) of the reactor pressure vessel (RPV) in the event of a core meltdown accident, several large-scale LHF experiments were performed under the USNRC/SNL LHF program. The experiments examined lower head failure at high pressures (10 MPa in most cases) and with small throughwall temperature differentials. Another USNRC/SNL LHF program, called the OLHF program, has been undertaken in the framework of an OECD project. This was an extension of the first program and dealt with low and moderate pressures (2–5 MPa) but with large through wall temperature differentials. These experiments should lead to a better understanding of the mechanical behavior of the reactor vessel lower head, which is of importance both in severe accident assessment and the definition of accident mitigation strategies. A well-characterized failure of the lower head is of prime importance for the evaluation of the quantity of core material that can escape into the containment, since this defines the initial conditions for all external-vessel events. The large quantity of escaping corium may lead to direct heating of the containment. This is an important severe accident issue because of its potential to cause early containment failure. The experiments also provide data for model development and validation. For our part, as one of the program partners, numerical modeling was performed to simulate these experiments. This paper presents a detailed description of three of our numerical models used for the simulation. The first model is a simplified semi-analytical approach based on the theory of a spherical shell subjected to internal pressure. The two other methods deal with 2D finite element (2D-FE) modeling: one combines the Norton–Bailey creep law with a damage model proposed by Lemaitre–Chaboche while the other uses only a creep failure criterion but takes into account thermo-metallurgical phase transformations. One of the objectives of the simulation is the development of a simplified and valid analytical code that can be implemented in integral severe accident computer codes. The numerical results are consistent with the experimental measurements. The effect on the numerical results of the multiphase transformation of the shell material and of the two failure criteria used, one involving necking (Considere's criterion) and the other involving creep damage (Lemaitre–Chaboche) is discussed.

This paper presents a methodology to evaluate the impact of the MC-CDMA physical layer algorithms on the downlink capacity in a multi-cellular environment. It presents a Monte Carlo simulation approach for capacity estimation at the system level and introduces a novel indicator for qualitative capacity evaluation at the link level. An illustration of this methodology shows very good agreement between the link level qualitative and system level quantitative capacity evaluations. The novel capacity indicator is therefore an efficient and accurate tool at the link level for optimizing the MC-CDMA physical layer algorithms and identifying the most appropriate physical layer configurations. On the other hand, the system level quantitative capacity evaluation allows to quantify more precisely the impact of the physical layer algorithms on the system capacity for a given environment.

International audience; This paper is concerned with the improvement of existing industrial control structures by the integration of human experience and expertise. Through two case studies concerning mechanical and petrochemical industries, it is illustrated that conventional control techniques and knowledge-based strategies can complement each other. The objective is to derive maximum profit from available materials and equipment by combining them efficiently. From a concrete point of view, linguistic fuzzy systems are used to achieve a collaboration between numeric and expert processing. Three distinct architectures are proposed to combine conventional regulators and knowledge-based procedures in a unified control structure. All of them are based on a context-oriented decomposition of the control problem under consideration. The choice of a particular architecture is then related to existing industrial installations and is finally dependent on company strategy.

International audience; This paper deals about the implementation of miniaturized microstrip band-pass filters operating on a very narrow bandwidth. We propose an original synthesis for achieving high out-of-band rejection by means of a 2nd order resonant structure, for which transmission zeros are introduced through mutual coupling effects. Quite good performances are obtained regarding losses, size and spurious resonances for the proposed topology, which can be considered as a good solution for future mobile on-board equipments

This paper deals about the implementation of miniaturized band-pass filters operating on a very narrow bandwidth. An original synthesis technique is proposed for achieving high out-of-band rejection by means of a loop resonator where transmission zeros are introduced through mutual coupling effects. Quite good performances are obtained regarding losses, size and spurious resonances for the proposed topology, which can be considered as a good solution for mobile equipments.

International audience; CMP aims at providing Universities, Research Laboratories and Industries with the facility to have their integrated circuits projects fabricated for prototyping and low volume production. During last 3 years, CMP introduced the access to new generation advanced technologies processes which are covering a wide spectrum of microelectronics, MEMS, and MCM technologies. In this paper we will describe and show some examples on how CMP Service succeeded transferring the knowledge of design techniques and methodology, targeting Deep Sub-Micron processes.

This paper investigates the absorbing layer techniques for three-dimensional transmission-line matrix (3d-tlm) simulations. Applications are the full-wave analysis of structures such as microwave and millimeter-wave circuits open to free space. Two approaches are presented, namely the matched layer (ml) and the perfectly matched layer (pml) technique which is used for general cases. For the ml technique, which is efficient for matching guides operating in a quasi-TEM condition, a comparison of the different tlm condensed node is carried out. Concerning the more general case of the pml technique, the theoretical development of a new general three-dimensional (3d) tlm condensed cell is presented. Results pertaining to the characterization of planar circuits are compared with other solutions or measurements. It is found that a proposed unified approach, which includes the tlm simulation for matched layer media, yields very good performance in terms of the absorbing boundary condition (abc).