WorldWideScience

Sample records for reseaux holographiques apodisants

  1. Detecteur multibandes libs a base de reseaux holographiques epais: Conception optomecanique et gestion de l'innovation

    Science.gov (United States)

    Gagnon, Daniel

    Detection of sulfur by optical emission spectroscopy generally presents difficulties because the strongest lines are in the vacuum ultraviolet and therefore are readily absorbed by oxygen molecules in air. A novel concept for a low cost and efficient system to detect sulfur using near infrared lines by Laser-Induced Breakdown Spectroscopy is proposed in this thesis. The concept proposes to use customized thick holographic gratings, also referred as Volume Bragg Grating, for spectral filtering of the plasma light, and built-in custom electronics that amplify and integrate photodiodes output signals. In this work, the optomechanical design, manufacturing and trials of a multiband sensor's prototype is reviewed. Preliminary results has been presented at NASLIBS 2011 and showed a limit of detection comparable to that of a conventional high-end system. An article describing the concept and results has been published in a special issue of the Applied Optics journal. To turn this newly patented concept into commercial success, the management of the innovation has been performed by proposing strategic and tactic alliances for commercialisation purposes applied to strategic business positioning structured along the 3 axis Technology -- Product -- Market. Open innovation is here acting as the paradigm to efficiently reach the market. Discussion relative to strategic and tactic alliance is actually taking place for deployment of the LIBS multiband sensor in the mining industry.

  2. Détection homodyne pour mémoires holographiques à stockage bit à bit

    Science.gov (United States)

    Maire, G.; Pauliat, G.; Roosen, G.

    2006-10-01

    Les mémoires holographiques à stockage bit à bit sont une alternative intéressante à l'approche holographique conventionnelle par pages de données du fait de leur architecture optique simplifiée. Nous proposons et validons ici une procédure de lecture adaptée à de telles mémoires et basée sur une détection homodyne de l'amplitude diffractée par les hologrammes. Ceci permet d'augmenter la quantité de signal utile détecté et s'avère donc prometteur pour accroître le taux de transfert de données de ces mémoires.

  3. Elements Optiques Holographiques Generes Par Ordinateur a Fonction de Phase Semi-Continue et Distribuee

    Science.gov (United States)

    Lemelin, Guylain

    Occupant une place grandissante dans la conception optique, les elements optiques holographiques (EOH) peuvent accomplir des taches qui seraient difficilement rendues par un groupe d'elements optiques conventionnels. Dans plusieurs systemes optiques utilisant une source laser, ces elements holographiques permettent d'imaginer des systemes optiques jusqu'ici impossibles a construire. Par consequent, ce type d'hologramme permet aux concepteurs la fabrication d'elements optiques speciaux. Nous presentons une etude d'EOH a fonction de phase semi-continue et distribuee qui augmente la capacite d'operation de ces elements optiques. Point tournant de notre developpement, nous avons mis au point une methode de fabrication par defocalisation simulee tres efficace, peu couteuse et facile a controler. Nous presentons des EOH simples qui demontrent les caracteristiques de base et des EOH plus complexes mettant en oeuvre des capacites speciales en fonction de leur utilisation specifique. Cette approche de conception optique holographique nous permet d'obtenir des EOH offrant une flexibilite d'optimisation et d'utilisation inegalee, augmentant ainsi les capacites de la conception optique.

  4. Un algorithme probabiliste d'election et d'arbre couvrant sur des reseaux anonymes

    OpenAIRE

    Lavallee, Ivan; Lavault, C.

    1989-01-01

    Dans le present rapport, nous proposons deux variantes d'un algorithme distribue, probabiliste, asynchrone d'election et de construction d'arbre couvrant dans des reseaux anonymes a topologie quelconque. A notre connaissance, cet algorithme est le premier du genre, a etre totalement et rigoureusement specifie. Il est fonde sur un precedent algorithme deterministe d'election pour reseaux de processus a identites distinctes. Nous montrons ici comment construire les deux variantes, suivant deux ...

  5. Fabrication et applications des reseaux de Bragg ultra-longs

    Science.gov (United States)

    Gagne, Mathieu

    This thesis presents the principal accomplishments realized during the PhD project. The thesis is presented by publication format and is a collection of four published articles having fiber Bragg gratings as a central theme. First achieved in 1978, UV writing of fiber Bragg gratings is nowadays a common and mature technology being present in both industry and academia. The property of reflecting light guided by optical fibers lead to diverse applications in telecommunication, lasers as well as several types of sensors. The conventional fabrication technique is generally based on the use of generally expensive phase masks which determine the obtained characteristics of the fiber Bragg grating. The fiber being photosensitive at those wavelengths, a periodic pattern can be written into it. The maximal length, the period, the chirp, the index contrast and the apodisation are all characteristics that depend on the phase mask. The first objective of the research project is to be able to go beyond this strong dependance on the phase mask without deteriorating grating quality. This is what really sets apart the technique presented in this thesis from other long fiber Bragg grating fabrication techniques available in the literature. The fundamental approach to obtain ultra long fiber Bragg gratings of arbitrary profile is to replace the scheme of scanning a UV beam across a phase mask to expose a fixed fiber by a scheme where the UV beam and phase mask are fixed and where the fiber is moving instead. To obtain a periodic index variation, the interference pattern itself must be synchronized with the moving fiber. Two variations of this scheme were implanted: the first one using electro-optical phase modulator placed in each arm of a Talbot interferometer and the second one using a phase mask mounted on a piezo electric actuator. A new scheme that imparts fine movements of the interferometer is also implemented for the first time and showed to be essential to achieve high

  6. Percolation dans des reseaux realistes de nanostructures de carbone

    Science.gov (United States)

    Simoneau, Louis-Philippe

    versatility in the choice of network components that can be simulated. The tools we have developed, grouped together in the RPH-HPN software Reseaux percolatifs hybrides - Hybrid Percolation Networks, construct random networks, detect contact between the tubes, translate the systems to equivalent electrical circuits and calculate global properties. An infinity of networks can have the same basic characteristics (size, diameter, etc.) and therefore the properties of a particular random network are not necessarily representative of the average properties of all networks. To obtain those general properties, we simulate a large number of random networks with the same basic characteristics and the average of the quantities is determined. The network constituent elements can be spheres, rods or snakes. The use of such geometries for network elements makes contact detection simple and quick, and more faithfully reproduce the form of carbon nanotubes. We closely monitor the geometrical and electrical properties of these elements through stochastic distributions of our choice. We can choose the length, diameter, orientation, chirality, tortuosity and impenetrable nature of the elements in order to properly reproduce real networks characteristics. We have considered statistical distribution functions that are rectangular, Gaussian, and Lorentzian, but all other distributions that can be expressed mathematically can also be envisioned. During the creation of a particular network, we generate the elements one by one. Each of their properties is sampled from a preselected distribution. Efficient algorithms used in various fields were adapted to our needs to manage the detection of contacts, clusters and percolation. In addition, we model more realistic contact between rigid nanotubes using an original method used to create the network that does not require a relaxation phase. Finally, we use Kirchhoff's laws to solve the equivalent electrical circuit conventionally. First, we evaluated

  7. Apodised aperture assembly for high power lasers

    International Nuclear Information System (INIS)

    Bliss, E.S.; Speck, D.R.

    1975-01-01

    An apodized aperture assembly using absorbing liquid or solid to vary transmission over the cross section thereof is used to minimize deleterious diffraction effects in high power lasers. By employing, for example, an absorbing liquid of varying optical density to obtain the transmission profile, a circular aperture of this type can be used to minimize diffraction effects, thereby substantially improving the performance of a high power laser system. (U.S.)

  8. Les reseaux de politique publique comme facteur d'influence du choix des instruments de politique energetique canadienne a des fins environnementales de 1993 a nos jours

    Science.gov (United States)

    Fathy El Dessouky, Naglaa

    Au cours de la derniere decennie, les modes de la gouvernance ont pris place dans un contexte totalement different de celui qu'ils avaient auparavant. Les gouvernements modernes se rendent compte qu'ils perdent de plus en plus leur capacite a elaborer et a gerer les changements d'une maniere autonome. Ainsi, les fonctions et les activites traditionnellement accomplies exclusivement par le gouvernement engagent de nos jours une gamme d'acteurs etatiques et non etatiques. A l'encontre du concept traditionnel de l'Etat controleur, la gouvernance contemporaine est ainsi devenue moins une question d'offre de service et davantage une gestion indirecte des reseaux de politique publique. Dans cette entreprise, les gouvernements contemporains, cherchant plus d'information, de soutien et de legitimite en matiere de formulation des decisions, ont besoin d'etablir des relations avec les divers groupes d'interet qui, a leur tour, voulaient plus de promotion et de protection en faveur de leurs interets a travers leur implication au processus de l'elaboration et de la mise en oeuvre des politiques publiques. Ainsi, l'approche des reseaux de politique publique represente aujourd'hui un courant considerable au sein du champ d'analyse des politiques publiques. Toutefois, les preoccupations des chercheurs pour cette approche, dans le domaine des politiques energetiques a des fins environnementales, semblent recentes, et les etudes realisees sont encore trop peu nombreuses. Au Canada, au debut des annees 1990, le gouvernement ainsi que plusieurs groupes d'interets, des differents secteurs energetique, industriel et environnemental, ont commence a intensifier leurs efforts pour s'attaquer au probleme du changement climatique d'origine energetique, genere surtout par le secteur de l'industrie. Au cours de la derniere decennie, la question touchant plutot le sujet du developpement energetique durable represente le plus important domaine des politiques publiques ayant surgi recemment dans

  9. Power grids; Reseaux electriques

    Energy Technology Data Exchange (ETDEWEB)

    Viterbo, J.

    2012-03-15

    The implementation of renewable energies represents new challenges for electrical systems. The objective: making power grids smarter so they can handle intermittent production. The advent of smart grids will allow flexible operations like distributing energy in a multidirectional manner instead of just one way and it will make electrical systems capable of integrating actions by different users, consumers and producers in order to maintain efficient, sustainable, economical and secure power supplies. Practically speaking, they associate sensors, instrumentation and controls with information processing and communication systems in order to create massively automated networks. Smart grids require huge investments: for example more than 7 billion dollars have been invested in China and in the Usa in 2010 and France is ranked 9. worldwide with 265 million dollars invested. It is expected that smart grids will promote the development of new business models and a change in the value chain for energy. Decentralized production combined with the probable introduction of more or less flexible rates for sales or purchases and of new supplier-customer relationships will open the way to the creation of new businesses. (A.C.)

  10. Studies of light water lattices by the homogeneous boron poisoning technique; Etude des reseaux a eau legere par la methode d'empoisonnement homogene au bore

    Energy Technology Data Exchange (ETDEWEB)

    Bailly, J.; Calament, J.; Girard, Y.; Golinelli, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    By homogeneously poisoning a critical facility with boric acid, one can balance important reactivities. Furthermore this technique is particularly interesting, due to the fact that it allows the substitution of cross sections to kinetic parameters in lattice calculations. With this use of boric acid as a poison arise important technological problems which are described in this report, the last part of which deals with the accuracy of the measurements made in these conditions. The main features of a lattice study made according to this moderator poisoning technique concern the determination of the concentration of dissolved boron which makes the multiplying assembly just critical and the determination of the reactivity factor as a function of temperature (this study has been carried out fill above 95 deg. C). (authors) [French] L'empoisonnement homogene d'une facilite critique par l'acide borique permet, outre d'effectuer des compensations de reactivites importantes, de jouer le role d'un intermediaire de mesure particulierement interessant par le fait qu'il conduit a substituer, dans le calcul des reseaux, des sections efficaces aux parametres cinetiques. Cette utilisation de l'acide borique comme poison ne va pas sans poser d'importants problemes technologiques qui sont decrits dans la presente etude, dont la derniere partie est consacree a la precision de mesures effectuees dans, ces conditions. Les points essentiels de l'etude d'un reseau suivant cette technique d'empoisonnement du moderateur, concernant la mesure de la concentration de bore dissous qui rend l'assemblage multiplicateur juste critique, ainsi que la determination du coefficient de reactivite en fonction de la temperature (l'etude a ete poussee au-dela de 95 deg. C). (auteurs)

  11. The Effect of Aberrations and Apodisation on the Performance of Coherent Imaging Systems.

    Science.gov (United States)

    1986-02-01

    effective in decreasing the amount oi eage ringing ri :ne acier -azec -rage )f an ed ge 7-e -inging ,ou’a .oe s.cessei ":-cwt-.e,.. optical system was free...svstem x:1. :e analyzed as an examole. For this ourpose, the ooticai system of ;;g- 5 1 -Vas - c s. uced v6,- e1 1 was a :aeaer’s z i 58 les (f -95 ",rri...Fourier Transform and it Application to Optics. 2no Edition, Wiley, New York. 4 Duffieux, P.M. and Lansraux, G.,(194S), " Les facteurs de transmission et

  12. Planification optimisee des reseaux electriques par la methode des ...

    African Journals Online (AJOL)

    L'objectif principal de cette planification est l'optimisation des coûts de production de ces sources d'énergie électrique renouvelables et de transit de puissance dans les lignes du réseau lors de leur insertion dans le réseau électrique en tenant compte de la quantité maximale de tonne de CO2 évitée pour la protection de ...

  13. Which energy networks for tomorrow?; Quels reseaux energetiques pour demain?

    Energy Technology Data Exchange (ETDEWEB)

    Lenoir, D. [CLER, 75 - Paris (France); Couturier, Ch. [Association Solagro, 31 - Toulouse (France); Batot, Ph. [Syndicat Departemental d' Energie et d' Equipements de la Vendee - SyDEU (France); Jedliczka, M. [Hespul, 69 - Villeurbanne (France); Belon, D. [Federation Nationale des Collectivites Concedantes et Regies - FNCCR, 75 - Paris (France); Goy, E. [AMORCE, 69 - Lyon (France); Bureau, L. [IZUBA, 34 - Meze (France)

    2010-07-01

    A set of brief articles outlines the importance of energy networks of all kinds for the future of energy conservation. Thus, all networks (communication, data, production command and control) will have a role to play to make all energy networks (electricity, gas, heat, cold, water, sewage, telecommunications) communicate with each other, and a new consumption/production model will have to be developed for each territory by taking into account its capacities to improve energy efficiency and valorize renewable energies. The authors also propose a historical perspective of network development and of their trend to become interconnected and complementary, comment the governance issue in terms of concession, evoke the supply of public networks with biogas (legal framework under development), discuss the value of the project of development of smart grids, suggest that a better electricity demand management could be an efficient alternative to grid development, comment the context and implications of the European directive Linky, outline that heat networks will contribute to the reduction of the environmental impact of buildings, evoke the issue of cold water networks and their impact on air conditioning, present the original heat network which is about to be built in Saint-Brieuc, etc.

  14. ELABORATION ET CARACTERISATION DE SUPER-RESEAUX Fe/Ag

    Directory of Open Access Journals (Sweden)

    F CHEMAM

    1999-12-01

    Full Text Available Des super-réseaux Fe/Ag ont été déposés sur des substrats MgO(001 par la technique d'épitaxie par jet  moléculaire (MBE sous un vide de 10-10 Torr.   L'analyse in-situ à l'aide de la  diffraction d'électrons RHEED a montré que les couches de fer  déposées sur MgO(001 croissent suivant l'orientation par rapport à la direction du substrat et que les couches d'argent  croissent sur Fe suivant la relation épitaxiale Ag(001//Fe(001.

  15. Reseaux de conception innovante et formes de proximites

    Directory of Open Access Journals (Sweden)

    Bénédicte Serrate

    2010-08-01

    Full Text Available La conception, appelée « design » dans les entreprises industrielles, représente dans le processus d’innovation une étape essentielle pourtant peu étudiée encore par les économistes. Elle mobilise pour aboutir à des innovations de plus en plus jugées essentielles à la compétitivité de l’entreprise, quantité d’acteurs internes et externes selon une logique de réseau sans cesse renouvelée. A partir de l’observation de cas empiriques, nous avons tenté dans cet article de comprendre comment s’organisaient ces réseaux innovants. Aujourd’hui dans la plupart des pays qui pratiquent des politiques de développement économique local, il semble établi qu’il faille construire des proximités géographiques entre acteurs pour que se développent des relations industrielles favorisant la dynamique d’innovation et le transfert des connaissances. L’abondance des « clusters » et des « pôles de compétitivité » partout dans le monde témoigne de ce postulat. En analysant les modes d’organisation des réseaux de conception nous avons donc cherché à vérifier si la proximité géographique constituait encore un ressort essentiel et si la globalisation des entreprises ne laissait pas apparaitre d’autres formes de proximités.

  16. Fundamental spatial mode size control of holographic laser oscillatorsContrôle spatial de la taille du mode fondamental des oscillateurs holographiques laser

    Science.gov (United States)

    Rosas, E.; Aboites, V.; Damzen, M. J.

    1998-12-01

    The spatial transient behaviour of the fundamental mode of a self-adaptive holographic laser oscillator was studied by using transfer matrix methods. The study began by considering a simple laser oscillator consisting of a plane output coupler and a nonlinear four-wave mixing (FWM) medium in a self-intersecting loop geometry. The system was then modified to consider infinite and finite FWM media, and additional intra-loop optical elements, such as lenses and Gaussian transmittance apertures. Results show that it is possible to generate and maintain the oscillation of large-volume modes allowing high energy extraction as well as good phase-conjugate quality and low-loss operation.

  17. Resetting dynamic behaviour of pipework systems; Recalage du comportement dynamique des reseaux de tuyauteries

    Energy Technology Data Exchange (ETDEWEB)

    Gaudin, M. [Electricite de France (EDF), Direction des Etudes et Recherches, 92 - Clamart (France)

    1997-12-31

    Resetting models is applied to electricity generating plant pipework systems. A frequency approach to the problem is made in an original way thanks to the use of precise dynamic rigidity matrices. The method assumes two kinds of unknown: the usually processed mechanical characteristics (Young`s Modulus, density etc.) and new resetting parameters acting on the dynamic behaviour of unknown connections. As the latter have a very wide range of possible variation, they benefit from a change of variable which allows the assumptions formulated to be complied with. The minimized cost function is based on a error in load. The frequencies required for building it are automatically selected thanks to different tests on measurements. Minimization uses a sensitivity technique linked with a method of least standard squares. The method has been programmed in Fortran 90 within the CIRCUS code and tried out on various examples which were simulated and sound effects cases as well as an actual case. (author). 128 refs.

  18. The elect and the heat networks; L'elu et les reseaux de chaleur

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-02-01

    Within the framework of the heat networks development in France the association AMORCE presents the advantages and examples of district heating using renewable energies or cogeneration. The heat networks have many advantages in terms of energy conservation and efficiency, but suffer often of juridical and financial handicaps. The association presents also the heat networks situation in Europe and the evolution perspectives. (A.L.B.)

  19. Human Systems Integration for Network Centric Warfare (Integration des systemes humains dans les operations reseaux centrees)

    Science.gov (United States)

    2010-02-01

    and perception in the local population in an area of operation in order to see whether opinions are changing to the better or worse for own forces...Requirements (e.g. training needs); • Local effects (e.g. opportunities for social learning). (in order) HV-B3 & F1 - HV-B1 & 5 HV-H HV-B2, F1 UK...ozbrojených síl SDG TECEN / DGAM M.R. Štefánika, Distribučné a C/ Arturo Soria 289 PAYS-BAS informačné stredisko RTO Madrid 28033 Royal

  20. Distributed Generation Management in Distribution Networks; Gestion de la production decentralisee dans les reseaux de distribution

    Energy Technology Data Exchange (ETDEWEB)

    Caire, R.

    2004-04-15

    Deregulations of the energy market, followed by many privatizations, and vertical disintegrations brought a complete reorganization of the electric sector. The opening of the energy markets as well as the technological developments of the means of production of small and average power strongly encourage this evolution. A systematic methodology to study the transmission of impacts between the Low and Medium Voltage is initially proposed, after a quick state of the art of the various possible impacts. The voltage deviation is then identified as the most critical impact. This criticality is supported by quantitative studies on French typical networks, and is confirmed by the related literature. In order to solve this impact, a research of the means of action within tension of the distribution network and their modeling is carried out. As the manipulated variables of the means of adjustment available are discrete or continuous, specific tools are then developed to coordinate them. This coordination is pressed on optimization algorithms developed by holding account of inherent specificity with the manipulated variables. A methodology for the choice or optimal location of the adjustment means associated with a management of the voltage deviation is presented. Lastly, 'decentralized' strategies of coordination for the means of adjustment and a proposal for an experimental validation are presented, thanks to a real time simulator, making it possible to test the strategies of coordination and the necessary means of communication. (author)

  1. District heating networks: tools for local organizations; Les reseaux de chaleur: outils des collectivites locales

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    In France, about 250 cities are equipped with district heating networks which contribute to the improvement of the energy mastery and of the air quality, to the reduction of the energy dependence and of the petroleum bill, to a better management of wastes, and to the local development (activity and employment). After a recall of the history of the development of district heating in France, this report describes the advantages of district heating in the national and local policies of: energy mastery, development of renewable energy sources and cogeneration systems, improvement of air quality, and economical and social development of urban areas. Two remarkable examples of district heating networks (Metz and Vitry le Francois) are presented in appendix. (J.S.)

  2. Interactive Visualization of Network Dynamics (Visualisation interactive de la dynamique des reseaux)

    Science.gov (United States)

    2014-06-01

    colour coding. The group factor f determines the structure of the hypernode and must be set with careful consideration in respect to the...reference. In experimental psychology it is a well accepted procedure to divide the frames of references into two categories: An egocentric reference...there is almost no colour contrast. For this reason the curvature and feature edges of a surface are harder to recognize and a matching between the

  3. Telecommunications networks, home integrated systems and remote control applications; Reseaux de telecommunications, domotique et teleaction

    Energy Technology Data Exchange (ETDEWEB)

    Cregut, F.; Treheux, M.

    1996-12-31

    Energy savings in residential sector can be performed by home integrated control systems. Remote controlled interfaces allow electric appliances consumption matching effective needs. Nevertheless, the uses of those techniques are stagnating since several years. The first reason is an awkward human factors engineering, that is now improving. The second reason is an lack of definition of the needs, that lead to commercialization problems. (D.L.)

  4. INTERACTION DES RESEAUX DE TRANSPORT ET DE DISTRIBUTION EN PRESENCE DE PRODUCTION DECENTRALISEE

    OpenAIRE

    Fontela Garcia, Miguel Angel

    2008-01-01

    The liberalisation or deregulation of the energy market and the futures lines fixed by the EU in order to increase the amount of clean energy make that the electric networks must be ready to integrate new energy injections, some of them intermittent. The construction of new lines and international connections could not be a solution which leads in any case to robust and flexible system. Robustness study methodology and definition are given in order to ensure the system robustness in case of h...

  5. Balancing of hot water distribution networks; Equilibrage des reseaux de distribution

    Energy Technology Data Exchange (ETDEWEB)

    Fridmann, P. [Societe Comap SA (France)

    1998-10-01

    The hydraulic balancing of hot water distribution networks is of prime importance for the optimum exploitation of air-conditioning installations. In the case of a non-correct balancing, heat exchangers, hot or cold batteries, water heaters or convection heaters are supplied by an insufficient or excessive water flow rate which disturbs the thermal equilibrium of the system and its correct regulation. The result is a degradation of the thermal comfort and a loss of energy. The aim of this technical paper is to precise the conditions of a good hydraulic (and thermal) balancing and the main rules to apply in order to avoid difficulties and counter-performances in space heating installations. The examples are restricted to closed and ramified hot or cold water networks and to a qualitative description of the phenomena: 1 - generalities (terminology, pressure drops, Z coefficients, network-pump coupling, thermosiphon effect, flow rate adjustment, flow and/or differential pressure regulation); 2 - application to the balancing of new installations (networks calculation principles, determination and adjustment of balancing equipments, follow up of hydraulic characteristics and prevention of disturbances); 3 - application to the balancing of existing installations; 4 - perspectives of evolution. (J.S.) 21 refs.

  6. New tariffs for transportation networks usage; Nouveaux tarifs d'utilisation des reseaux de transport

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2008-09-15

    New tariffs of gas transportation networks usage will be enforced on January 1, 2009. They will greatly simplify the access to transportation networks, favorable to the development of competition, and will allow market actors to have a better visibility. They represent a favorable framework for investments on the transportation network and will incite the gas suppliers to improve their quality of service and to control their expenses. (J.S.)

  7. REFLEXION AUTOUR DES MODES DE STRUCTURATION DES RESEAUX DE SANTE ET DES ORGANISATIONS EN SANTE

    Directory of Open Access Journals (Sweden)

    Bertrand PAUGET

    2013-11-01

    Full Text Available This theoretical paper is based on previous articles written by the author. Indeed, we believe that the organizations must be analyzed beyond the classic opposition between mechanistic and organic organizations (Burn and Stakler, 1961 Wine et al., 2006. The organizations in the health sector are seen as a relational organization. We explore the potential outcomes of this vision of the organization.

  8. Some general rules governing huge power networks; Quelques regles generales gouvernant les grands reseaux electriques

    Energy Technology Data Exchange (ETDEWEB)

    Clade, J. [Electricite de France (EDF), 75 - Paris (France)

    2010-12-15

    The very large networks operate on vast territories, on the scale not only of countries, but of continents. Their aim is twofold: transmitting electrical energy from the power plants - nuclear or thermal power plants, hydraulic, wind power plants etc. - to consumption areas (that is the transmission function); pooling the power plants, so as to operate at any time those which are the less expensive (interconnection of energy production) and to guarantee a safe continuous supply to the users (interconnection of power). However, the transmission of electrical energy is more costly than transmission, when possible, of primary energy sources, either fossil fuels or nuclear. When the sources are not chiefly hydraulic, it is pertinent to limit the transmission of electricity by siting the power plants as close as possible to the consumption areas. On the contrary, interconnection may allow significant savings in the way of power plant investments and fuel expenses. Therein is the main economical justification for very large electrical systems and networks, except in cases where distant hydraulic sources are operated. We must then think over large electrical networks mainly as tools for cooperation between power producers, aiming at an electrical supply to customers which is safe, continuous and as inexpensive as possible. (author)

  9. Bayesian networks for management of industrial risk; Reseaux Bayesiens pour la maitrise des risques industriels

    Energy Technology Data Exchange (ETDEWEB)

    Munteanu, P. [Bayesia SA, 53 - Laval (France); Debache, G. [Dassault Aviation, 92 - Saint Cloud (France); Duval, C. [Electricite de France (EDF), 78 - Chatou (France)

    2008-09-15

    This article presents the outlines of Bayesian networks modelling and argues for their interest in the probabilistic studies of industrial risk and reliability. A practical case representative of this type of study is presented in support of the argumentation. The article concludes on some research tracks aiming at improving the performances of the methods relying on Bayesian networks and at widening their application area in risk management. (authors)

  10. Cold atoms: optical gratings and atomic clocks; Atomes froids: reseaux optiques et horloges

    Energy Technology Data Exchange (ETDEWEB)

    Leduc, M. [Lab. Kastler Brossel, Ecole Normale Superieure, 75 - Paris (France); Lemonde, P. [Syrte, Observatoire de Paris, 75 - Paris (France)

    2010-10-15

    The domain of cold atoms is flourishing. The light-matter interaction allows a gas to be cooled below 10{sup -6} K and to be trapped in vacuum. Atoms lasers are based on Bose-Einstein condensates. Trapped in optical gratings by stationary waves, ultra-cold fermionic atoms can be considered as models for the understanding of condensed matter physics

  11. APPLICATION DES ENSEMBLES FLOUS A LA REPARTITION OPTIMALE DE LA PUISSANCE DANS LES RESEAUX ELECTRIQUES

    Directory of Open Access Journals (Sweden)

    A. Guediri

    2011-06-01

    Full Text Available Optimal power flow calculation (OPF, used to optimize specific aspects of power system operations, usually employ standard mathematical programming techniques. These techniques are not suitable to handle many practical considerations encountered in power systems, including the uncertainty of the operational constraints [1].They can be relaxed temporarily, if necessary, to obtain feasible solutions. For taking well into account this type of constraints, one proposes in this work the application of a method based on fuzzy sets to the OPF problem. The developed method has been tested on standard scale power systems (IEEE30bus.

  12. The promises of intelligent power grids; Les promesses des reseaux electriques intelligents

    Energy Technology Data Exchange (ETDEWEB)

    Dupin, L

    2009-12-15

    The 'smart grids', or intelligent power networks, are passing from project to realization. The goal is to optimize networks to limit losses and favor the use of low-CO{sub 2} energy sources. The world market of smart grids should reach 65 billion dollars by 2013. It will involve massive upgrades of softwares and equipments in the years to come. The whole electric power industry is concerned by this evolution, from the power grid operators (RTE, ERDF, Elia, National Grid, Vattenfall..) to the electric utilities (EdF, Electrabel, GdF Suez..) and the alternate operators, the solution suppliers, the electrical equipment and cable manufacturers etc. Power substations will be fitted with sensors and remotely managed and maintained thanks to powerful communication networks. (J.S.)

  13. Photovoltaic production and distribution network; La production photovoltaique et les reseaux de distribution

    Energy Technology Data Exchange (ETDEWEB)

    Fraisse, J.L. [ERDF, 75 - Paris (France)

    2010-04-15

    The rapid development of photovoltaics boosted by attractive feed-in tariffs caused a sharp increase in requests for connection to public distribution grids, which were originally designed to serve consumers. ERDF, main distribution network operator in France, is facing a challenge in terms of capacity for handling requests for connection and in terms of public distribution network operation and management. (author)

  14. ANALYSE DE RISQUE ET DETECTION D'INTRUSIONS POUR LES RESEAUX AVIONIQUES

    OpenAIRE

    Gil-Casals , Silvia

    2014-01-01

    Aeronautics is actually facing a confluence of events: connectivity of aircraft is gradually increasing in order to ease the air traffic management and aircraft fleet maintainability, and to offer new services to passengers while reducing costs. The core avionics functions are thus linked to what we call the Open World, i.e. the non-critical network of an aircraft as well as the air traffic services on the ground. Such recent evolutions could be an open door to cyber-attacks as their complexi...

  15. Optimization of investments in gas networks; Optimisation des investissements sur les reseaux de gaz

    Energy Technology Data Exchange (ETDEWEB)

    Andre, J.

    2010-09-15

    The natural gas networks require very important investments to cope with a still growing demand and to satisfy the new regulatory constraints. The gas market deregulation imposed to the gas network operators, first, transparency rules of a natural monopoly to justify their costs and ultimately their tariffs, and, second, market fluidity objectives in order to facilitate access for competition to the end-users. These major investments are the main reasons for the use of optimization techniques aiming at reducing the costs. Due to the discrete choices (investment location, limited choice of additional capacities, timing) crossed with physical non linear constraints (flow/pressures relations in the pipe or operating ranges of compressors), the programs to solve are Large Mixed Non Linear Programs (MINLP). As these types of programs are known to be hard to solve exactly in polynomial times (NP-hard), advanced optimization methods have to be implemented to obtain realistic results. The objectives of this thesis are threefold. First, one states several investment problems modeling of natural gas networks from industrial world motivations. Second, one identifies the most suitable methods and algorithms to the formulated problems. Third, one exposes the main advantages and drawbacks of these methods with the help of numerical applications on real cases. (author)

  16. Reseaux d’Antennes Controles par Ordinateur (Computer-Controlled Antenna Arrays).

    Science.gov (United States)

    1977-04-01

    par ordinateur Figure 2. Equivalent electrique de l’antenne Figure 3, Coefficient de reflection Figure 4. Dimensions physique de l’antenne...Figure 5. Photographie de l’antenne dipole Figure 6. Coefficient de reflection de 4 antennes differentes presente sur "Smith Chart" Figure 7. Reglage...transition d’impedance de la ligne 1 transmission (50 OHMS) ä la resistance de radiation d’un dipole dans • ••.pace (73 OHMS). Ces calculs

  17. Ion conducting interpenetrated lattices for lithium generators; Reseaux interpenetres conducteurs ioniques pour generateurs au lithium

    Energy Technology Data Exchange (ETDEWEB)

    Grosz, M.; Boileau, S. [College de France, 75 - Paris (France); Guegan, P.; Cheradame, H. [Centre National de la Recherche Scientifique (CNRS), 94 - Thiais (France). LPCB; Deshayes, A. [CNET, 92 - Issy-les-Moulineaux (France)

    1996-12-31

    Interpenetrated lattices (IPL) are combinations of reticulated polymers linked together by permanent crisscross. This structure is well-adapted to combined highly incompatible pairs of polymers. The in-situ sequential method has been applied successfully to the synthesis of ethylene poly-oxides / poly-siloxanes IPLs. The results concerning the preparation of such lattices and their behaviour as solid polymer electrolytes are presented in this paper. (J.S.) 24 refs.

  18. A Framework for Network Visualisation (Un Cadre Pour la Visualisation des Reseaux)

    Science.gov (United States)

    2010-02-01

    fruition until the near-success of the 1605 “Gunpowder Plot” two years after Elizabeth’s death , the thwarting of which is still celebrated in England...on general-purpose atlas reference maps from a semiotics point of view. The simplest definition of semiotics is perhaps “the study of sign systems...the Association of American Geographers, 71(2):253-258, 1981. [14] Head, C.G., “Mapping as Language or Semiotic System: Review and Comment”, In

  19. Computerized Library and Information Network Contracts. Proposed Guidelines and Definitions. Canadian Network Papers Number 8 = Les Contrats de Reseaux de Bibliotheques et d'Information Telematiques. Principes Directeurs et Definitions Proposes. Documents sur les Reseaux Canadiens Numero 8.

    Science.gov (United States)

    Ahluwalia, Rajesh; Duchesne, Roddy

    Based on a directive from the National Advisory Board of Canada, this paper provides a set of definitions and guidelines which Canadian libraries may choose to use in negotiating their contracts with database suppliers, vendors, and other information and bibliographic services. The report is intended to: (1) provide a basis for understanding and…

  20. Validation materielle d'une architecture generique de reseaux avioniques basee sur une gestion modulaire de la redondance

    Science.gov (United States)

    Tremblay, Jose-Philippe

    Les systemes avioniques ne cessent d'evoluer depuis l'apparition des technologies numeriques au tournant des annees 60. Apres le passage par plusieurs paradigmes de developpement, ces systemes suivent maintenant l'approche " Integrated Modular Avionics " (IMA) depuis le debut des annees 2000. Contrairement aux methodes anterieures, cette approche est basee sur une conception modulaire, un partage de ressources generiques entre plusieurs systemes et l'utilisation plus poussee de bus multiplexes. La plupart des concepts utilises par l'architecture IMA, bien que deja connus dans le domaine de l'informatique distribuee, constituent un changement marque par rapport aux modeles anterieurs dans le monde avionique. Ceux-ci viennent s'ajouter aux contraintes importantes de l'avionique classique telles que le determinisme, le temps reel, la certification et les cibles elevees de fiabilite. L'adoption de l'approche IMA a declenche une revision de plusieurs aspects de la conception, de la certification et de l'implementation d'un systeme IMA afin d'en tirer profit. Cette revision, ralentie par les contraintes avioniques, est toujours en cours, et offre encore l'opportunite de developpement de nouveaux outils, methodes et modeles a tous les niveaux du processus d'implementation d?un systeme IMA. Dans un contexte de proposition et de validation d'une nouvelle architecture IMA pour un reseau generique de capteurs a bord d?un avion, nous avons identifie quelques aspects des differentes approches traditionnelles pour la realisation de ce type d?architecture pouvant etre ameliores. Afin de remedier a certaines des differentes lacunes identifiees, nous avons propose une approche de validation basee sur une plateforme materielle reconfigurable ainsi qu'une nouvelle approche de gestion de la redondance pour l'atteinte des cibles de fiabilite. Contrairement aux outils statiques plus limites satisfaisant les besoins pour la conception d'une architecture federee, notre approche de validation est specifiquement developpee de maniere a faciliter la conception d'une architecture IMA. Dans le cadre de cette these, trois axes principaux de contributions originales se sont degages des travaux executes suivant les differents objectifs de recherche enonces precedemment. Le premier axe se situe au niveau de la proposition d'une architecture hierarchique de reseau de capteurs s'appuyant sur le modele de base de la norme IEEE 1451. Cette norme facilite l'integration de capteurs et actuateurs intelligents a tout systeme de commande par des interfaces normalisees et generiques.

  1. Solubilisation de filtres-UV dans des melanges ternaires de phases apolaires, optimisation par l'utilisation de reseaux centres.

    Science.gov (United States)

    Marti-Mestres, G; Laget, J P; Maillols, H; Fernandez, C

    1998-02-01

    This paper is concerned with the solubility of UV filters. Emulsions are perfect formulations used for sunscreens, but to give the skin silky feel without being greasy, the oily phase content is low. Considerations of sunscreen solubility can help to solve specific problems of stability in formulations. It is important to determine what solvent dissolves them and what mixture of solvent improves their solubility. Two water insoluble sunscreens were tested at several concentrations in various non-polar solvents. A strategy with simplex centroid design was used to optimize this work. The graphical interpretation of the data assists our understanding of the solubility of UV filters.

  2. Probabilistic modeling of crack networks in thermal fatigue; Modelisation probabiliste de formation de reseaux de fissures de fatigue thermique

    Energy Technology Data Exchange (ETDEWEB)

    Malesys, N

    2007-11-15

    Thermal superficial crack networks have been detected in mixing zone of cooling system in nuclear power plants. Numerous experimental works have already been led to characterize initiation and propagation of these cracks. The random aspect of initiation led to propose a probabilistic model for the formation and propagation of crack networks in thermal fatigue. In a first part, uniaxial mechanical test were performed on smooth and slightly notched specimens in order to characterize the initiation of multiple cracks, their arrest due to obscuration and the coalescence phenomenon by recovery of amplification stress zones. In a second time, the probabilistic model was established under two assumptions: the continuous cracks initiation on surface, described by a Poisson point process law with threshold, and the shielding phenomenon which prohibits the initiation or the propagation of a crack if this one is in the relaxation stress zone of another existing crack. The crack propagation is assumed to follow a Paris' law based on the computation of stress intensity factors at the top and the bottom of crack. The evolution of multiaxial cracks on the surface can be followed thanks to three quantities: the shielding probability, comparable to a damage variable of the structure, the initiated crack density, representing the total number of cracks per unit surface which can be compared to experimental observations, and the propagating crack density, representing the number per unit surface of active cracks in the network. The crack sizes distribution is also computed by the model allowing an easier comparison with experimental results. (author)

  3. "WorldFIP Diagnostic Line Driver" (FIPDLD) Derivateur de ligne pour diagnostic sur les reseaux WorldFIP du LHC

    CERN Document Server

    Brun, R

    2006-01-01

    Dans le cadre du nouvel accélérateur de particules LHC, le CERN utilise un réseau WorldFIP pour remonter les informations numériques et analogiques liées aux différents systèmes de contrôle de la machine. Compte tenu du grand nombre de segments (plus de 250) et d'agents (plus de 12000), il est nécessaire de s'équiper d'outils facilitant le diagnostic opérationnel sur ces différents réseaux. L'outil principal d'analyse actuel est un PC portable équipé du logiciel FIPWATCHER qui se raccorde au réseau WorldFIP au niveau d'une prise Agent. Pour l'équipe support, un raccordement sur un boîtier de dérivation TAP simplifierait cette connexion et éviterait le débranchement et re-branchement de l'agent pour insérer le dérivateur FIPWATCHER.

  4. Le systeme d’information des reseaux de sante: la reorganisation de la medecine en e-sante

    Directory of Open Access Journals (Sweden)

    Maryline Margueritte

    2013-01-01

    Full Text Available Les réseaux de santé ont développé depuis plusieurs années des dispositifs permettant une prise en charge coordonnée des patients en France, tant sur les plans médical que médico-psycho-social et humain. Certains ont développé des dossiers de santé partagés informatisés permettant la mise en commun d’informations utiles à la coordination et à la continuité des soins. Depuis 2009 avec la réforme de l’hôpital on veut installer des modes de fonctionnement coopératifs entre les professionnels et avec les usagers du système de santé. La mise en œuvre d’un système d’information de santé pour assurer d’une part, la transversalité du processus métier avec le patient et d’autre part pouvoir mesurer les résultats médicaux et économiques de cette évolution d’un système complexe d’information. Dans ce contexte, les possibilités offertes par les technologies de l’information et de la communication (TIC permettent la mise en place d’applications favorisant une augmentation de la participation « on line » des citoyens. Le « virage ambulatoire » exporte la santé hors des murs. C’est une médecine innovante qui permet au patient de rester dans son « chez soi ». En France, ce re-engeneering repose sur quatre domaines : un dossier médical informatisé, une prise en charge collective par les professions médicales et paramédicales, une autonomisation et une mise en réseau du secteur de santé.

  5. Solution des systemes de controle de grandes dimensions basee sur les boucles de retroaction dans la simulation des reseaux electriques

    Science.gov (United States)

    Mugombozi, Chuma Francis

    The generation of electrical energy, as well as its transportation and consumption, requires complex control systems for the regulation of power and frequency. These control systems must take into account, among others, new energy sources such as wind energy and new technologies for interconnection by high voltage DC link. These control systems must be able to monitor and achieve such regulation in accordance with the dynamics of the energy source, faults and other events which may induce transients phenomena into the power network. Such transients conditions have to be analyzed using the most accurate and detailed hence, complex models of control system. In addition, in the feasibility study phase, the calibration or the setup of equipment as well as in the operation of the power network, one may require decision aid tools for engineers. This includes, for instance, knowledge of energy dissipated into the arresters in transient analysis. These tools use simulation programs data as inputs and may require that complex functions be solved with numerical methods. These functions are part of control system in computer simulator. Moreover, the simulation evolves in a broader context of the development of digital controller, distributed and parallel high performance computing and rapid evolutions in computer (multiprocessor) technology. In such context, a continuing improvement of the control equations solver is welcomed. Control systems are modelled using ax=b simultaneous system of equations. These equations are sometimes non-linear with feedback loops and thus require iterative Newton methods, including the formation of a Jacobian matrix and ordering as well as processing by graph theory tools. The proposed approach is based on the formulation of a reduced rank Jacobian matrix. The dimension is reduced up to the count of feedback loops. With this new approach, gains in computation speed are expected without compromising its accuracy when compared to classical full rank Jacobian matrix representation. A directed graph representation is adopted and a proper approach for detecting and removing cycles within the graph is introduced. A condition of all zero eigenvalues of adjacency matrix of the graph is adopted. The transformation of the graph of controls with no cycle permits a formulation of control equations for only feedback points. This yields a general feedback interconnection (GFBI) representation of control, which is the main contribution of this thesis. Methods for solving (non-linear) equations of control systems were deployed into the new GFBI approach. Five variants of the new approach were illustrated including firstly, a basic Newton method (1), a more robust one, the Dogleg method (2) and a fixed-point iterations method (3). I. The presented approach is implemented in Electromagnetic Transient program EMTP-RV and tested on practical systems of various types and levels of complexity: the PLL, an asynchronous machine with 87 blocks reduced to 23 feedback equations by GFBI, and 12 wind power plants integrated to the IEEE-39 buses system. Further analysis, which opens up avenues for future research includes comparison of the proposed approach against existing ones. With respect to the sole representation, it is shown that the proposed approach is equivalent to full classic representation of system of equations through a proper substitution process which complies with topological sequence and by skipping feedback variable identified by GFBI. Moreover, a second comparison with state space based approach, such as that in MATLAB/Simulink, shows that output evaluation step in state-space approach with algebraic constraints is similar to the GFBI. The algebraic constraints are similar to feedback variables. A difference may arise, however, when the number of algebraic constraints is not the optimal number of cuts for the GFBI method: for the PLL, for example, MATLAB/Simulink generated 3 constraints while the GFBI generated only 2. The GFBI method may offer some advantages in this case. A last analysis axis prompted further work in initialization. It is shown that GFBI method may modifies the convergence properties of iterations of the Newton method. The Newton- Kantorovich theorem, using bounds on the norms of the Jacobian, has been applied to the proposed GFBI and classic full representation of control equations. The expressions of the Jacobian norms have been established for generic cases using Coates graph. It appears from the analysis of a simple case, for the same initial conditions, the behaviour of the Newton- Kantorovich theorem differs in both cases. These differences may also be more pronounced in the non-linear case. Further work would be useful to investigate this aspect and, eventually, pave the way to new initialization approaches. Despite these limitations, not to mention areas for improvement in further work, one notes the contribution of this thesis to improve the gain of time on simulation for the solution of control systems. (Abstract shortened by UMI.).

  6. Fine tuning of transmission features in nanoporous anodic alumina distributed Bragg reflectors

    Science.gov (United States)

    Lim, Siew Yee; Law, Cheryl Suwen; Santos, Abel

    2018-01-01

    This study introduces an innovative apodisation strategy to tune the filtering features of distributed Bragg reflectors based on nanoporous anodic alumina (NAA-DBRs). The effective medium of NAA-DBRs, which is modulated in a stepwise fashion by a pulse-like anodisation approach, is apodised following a logarithmic negative function to engineer the transmission features of NAA-DBRs. We investigate the effect of various apodisation parameters such as apodisation amplitude difference, anodisation period, current density offset and pore widening time, to tune and optimise the optical properties of NAA-DBRs in terms of central wavelength position, full width at half maximum and quality of photonic stop band. The transmission features of NAA-DBRs are shown to be fully controllable with precision across the spectral regions by means of the apodisation parameters. Our study demonstrates that an apodisation strategy can significantly narrow the width and enhance the quality of the characteristic photonic stop band of NAA-DBRs. This rationally designed anodisation approach based on the combination of apodisation and stepwise pulse anodisation enables the development of optical filters with tuneable filtering features to be integrated into optical technologies acting as essential photonic elements in devices such as optical sensors and biosensors.

  7. On the Design of Distributed Organizational Structures,

    Science.gov (United States)

    1986-08-01

    J. L. Peterson, Petri Net Theory and the Modeling of Systems, Prentice-Hall, Englewood Cliffs, NJ, 1981. ". • [6] G.W. Brams, Reseaux de Petri...des Reseaux de Petri, These 3eme Cycle, Universite Paris VI, 1981. [121 S. Weingaertner, "A Model of Submarine Emergency Decisionmaking and . Decision

  8. Employing Deceptive Dynamic Network Topology Through Software-Defined Networking

    Science.gov (United States)

    2014-03-01

    Request For Comments RIP Routing Information Protocol RIPE NCC Reseaux IP Europeans Network Coordination Center RIR Regional Internet Registries RTT...Another large research project in building Internet measurement infrastructure is from the Reseaux IP Europeans Network Coordination Center (RIPE NCC) [24

  9. Naval C3 Distributed Tactical Decision Making.

    Science.gov (United States)

    1986-07-27

    Brains, Reseaux de Petri: Theorie et Pratique. Masson, Paris, 1983. [7] W. Brauer, Net Theory and Applications, Proceedings of the Advanced Course on...Springer-Verlag #52, Berlin, 1980. [10] J. M. Toudic, Algorithmes d’analyse Structurelle des Reseaux De Petri, These 3 Cycle, Universite Paris VI, 1981. 16 DATE FILMED

  10. Filtrage actif des harmoniques en courant et en tension des reseaux électriques : modélisation, simulation numérique et expérimentation

    Science.gov (United States)

    Lott, C.; Lapierre, O.; Pouliquen, H.; Saadate, S.

    1997-12-01

    Static converters generate harmonic currents and consume reactive power. These new phenomena on the mains generate some perturbations going from malfunction to destruction of the connected sensible equipments. In this paper disturbances generated by static converters are studied. Some solutions based on passive and active filtering are presented. Some passive filter design elements are given. Active filter is then studied. Both structures, current and voltage, are studied and voltage source structure is chosen. Different active filter control principles are presented. The active and reactive instantaneous power theory give good results for harmonic identification. Some numerical simulation are realized. A 100kVA prototype is realized and tested on an industrial site. The GTO prototype shows good results for harmonic filtering. The voltage active filtering is also presented. The active filter eliminates voltage harmonics on 400 V busbar generated by a MVA SCR bridge connected on 15kV busbar. Les convertisseurs statiques absorbent des courants non sinusoïdidaux et consomment généralement de la puissance réactive. Ces deux phénomènes nouveaux sur le réseau ont engendré un certain nombre de perturbations allant du dysfonctionnement d'un équipement jusqu'à la destruction d'une partie des équipements connectés. Dans cet article, les problèmes liés aux perturbations générées par les convertisseurs statiques ont été étudiés et des solutions visant à les éliminer ont été présentées. Elles portent sur les méthodes de filtrage passif et actif. Quelques éléments de définition et de dimensionnement de filtres passifs sont donnés. Le filtrage actif est ensuite traité. Les deux structures, courant et tension, sont étudiées et la structure tension a été retenue pour la suite de l'article. Différents principes de contrôle du filtre actif à structure tension ont été présentés. La méthode d'identification des harmoniques par le principe du calcul des puissances active et réactive instantanées donne des résultats satisfaisants. Des simulations numériques ont été réalisées. Enfin une maquette expérimentale de 100kVA a été réalisée et testée sur un site industriel. Les essais de la maquette ont montré de bonnes performances du filtre actif à thyristor GTO. Le filtrage en tension d'un jeu de barres perturbé par un convertisseur de 5MVA connecté sur un réseau amont a également été réalisé et étudié dans cet article.

  11. Hydraulic properties of fracture networks; Analyse des proprietes hydrauliques des reseaux de fractures: discussion des modeles d'ecoulement compatibles avec les principales proprietes geometriques

    Energy Technology Data Exchange (ETDEWEB)

    Dreuzy, J.R. de

    1999-12-15

    Fractured medium are studied in the general framework of oil and water supply and more recently for the underground storage of high level nuclear wastes. As fractures are generally far more permeable than the embedding medium, flow is highly channeled in a complex network of fractures. The complexity of the network comes from the broad distributions of fracture length and permeability at the fracture scale and appears through the increase of the equivalent permeability at the network scale. The goal of this thesis is to develop models of fracture networks consistent with both local-scale and global-scale observations. Bidimensional models of fracture networks display a wide variety of flow structures ranging from the sole permeable fracture to the equivalent homogeneous medium. The type of the relevant structure depends not only on the density and the length and aperture distributions but also on the observation scale. In several models, a crossover scale separates complex structures highly channeled from more distributed and homogeneous-like flow patterns at larger scales. These models, built on local characteristics and validated by global properties, have been settled in steady state. They have also been compared to natural well test data obtained in Ploemeur (Morbihan) in transient state. The good agreement between models and data reinforces the relevance of the models. Once validated and calibrated, the models are used to estimate the global tendencies of the main flow properties and the risk associated with the relative lack of data on natural fractures media. (author)

  12. On the integration of wind generators on weak grids and island grids; Sur l'integration des generateurs eoliens dans les reseaux faibles ou insulaires

    Energy Technology Data Exchange (ETDEWEB)

    Laverdure, N

    2005-12-15

    Wind energy is now an energy that can not be ignored. Because of intrinsic characteristics (scattered primary energy, generators with different technologies, use of power electronics interface), wind energy system integration in distribution grids leads to real problems in terms of impacts. With recent standard changes, it is necessary to study the possibilities of each technology of wind turbines to answer or not to these new constraints. This PhD thesis focuses on a comparison of the main present wind turbines concerning three points of discussion: energy quality, fault ride through, ancillary services (voltage and frequency). It insists on the possibilities in terms of control laws for variable speed wind turbines. (author)

  13. History matching of large scale fractures to production data; Calage de la geometrie des reseaux de fractures aux donnees hydrodynamiques de production d'un champ petrolier

    Energy Technology Data Exchange (ETDEWEB)

    Jenni, S.

    2005-01-01

    Object based models are very helpful to represent complex geological media such as fractured reservoirs. For building realistic fracture networks, these models have to be constrained to both static (seismic, geomechanics, geology) and dynamic data (well tests and production history). In this report we present a procedure for the calibration of large-scale fracture networks to production history. The history matching procedure includes a realistic geological modeling, a parameterization method coherent with the geological model and allowing an efficient optimization. Fluid flow modeling is based on a double medium approach. The calibration procedure was applied to a semi-synthetic case based on a real fractured reservoir. The calibration to water-cut data was performed. (author)

  14. Parallelization of applications for networks with homogeneous and heterogeneous processors; Parallelisation d`applications pour des reseaux de processeurs homogenes ou heterogenes

    Energy Technology Data Exchange (ETDEWEB)

    Colombet, L.

    1994-10-07

    The aim of this thesis is to study and develop efficient methods for parallelization of scientific applications on parallel computers with distributed memory. The first part presents two libraries of PVM (Parallel Virtual Machine) and MPI (Message Passing Interface) communication tools. They allow implementation of programs on most parallel machines, but also on heterogeneous computer networks. This chapter illustrates the problems faced when trying to evaluate performances of networks with heterogeneous processors. To evaluate such performances, the concepts of speed-up and efficiency have been modified and adapted to account for heterogeneity. The second part deals with a study of parallel application libraries such as ScaLAPACK and with the development of communication masking techniques. The general concept is based on communication anticipation, in particular by pipelining message sending operations. Experimental results on Cray T3D and IBM SP1 machines validates the theoretical studies performed on basic algorithms of the libraries discussed above. Two examples of scientific applications are given: the first is a model of young stars for astrophysics and the other is a model of photon trajectories in the Compton effect. (J.S.). 83 refs., 65 figs., 24 tabs.

  15. Multi-criteria optimization of dryers: use of neural networks and genetical algorithms; Optimisation multi-criteres de sechoirs: utilisation des reseaux de neurones et algorithmes genetiques

    Energy Technology Data Exchange (ETDEWEB)

    Hugget, A.; Nadeau, J.P.; Sabastian, P. [Ecole Nationale Superieure des Arts et Metiers, 33 - Talence (France)

    1997-12-31

    Drying remains a complex process to model and thus to optimize. In this paper a new approach is proposed which allows to perform a compression in the drying model in order to integrate it using neural networks. The simulation times become very small and allow to test a great number of configurations. This decisive advantage allows to perform a multi-criteria optimization using hybrid genetical algorithms based on technical-economical criteria like drying cost, production or final product quality. (J.S.) 10 refs.

  16. Processus de modelisation et etude des orages geomagnetiques dans les reseaux electriques: Impact sur le reseau de transport d'Hydro-Quebec

    Science.gov (United States)

    Abdellaoui, Amr

    This research project presents a complete modelling process of the effects of GIC on Hydro-Quebec power system network for system planning studies. The advantage of the presented method is that it enables planning engineers to simulate the effects of geomagnetic disturbances on the Hydro-Quebec System under different conditions and contingencies within reasonable calculation time frame. This modelling method of GIC in electric power systems has been applied to the Hydro-Quebec System. An equivalent HQ DC model has been achieved. A numerical calculation method of DC sources from a non-uniform geoelectric field has been developed and implemented on HQ DC model. Harmonics and increased reactive power losses of saturated transformers have been defined as a function of GIC through a binary search algorithm using a chosen HQ magnetization curve. The evolution in time of each transformer saturation according to its effective GIC has been evaluated using analytical formulas. The reactive power losses of saturated transformers have been modeled in PSS/E[1] HQ network as constant reactive current loads assigned to the corresponding transformer buses. Finally, time domain simulations have been performed with PSS/E taking into account transformer saturation times. This has been achieved by integrating HQ DC model results and analytical calculations results of transformer saturation times into an EMTP load model. An interface has been used to link EMTP load model to HQ PSS/E network. Different aspects of GIC effects on the Hydro-Quebec system have been studied, including the influence of uniform and non-uniform geoelectric fields, the comparison of reactive power losses of the 735kV HQ system with those of Montreal network, the risks to voltage levels and the importance of reactive power dynamic reserve. This dissertation presents a new GIC modelling approach for power systems for planning and operations purposes. This methodology could be further enhanced, particularly, the aspect regarding the transformer saturation times. Hence more research remains to be pursued in this area.

  17. Development of public power transportation and distribution networks; Developpement des reseaux publics de transport et de distribution de l'electricite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-09-01

    This circular deals with the development of the French public power transportation network, but also with projects of public distribution networks with a voltage greater or equal to 63 kV. The following points are successively evoked: the planing of the development of the public power transportation network, the preliminary study of the advisability of projects of high and very high voltage power systems, the discussion of projects, the environmental integration of project, and the accompanying measures. (J.S.)

  18. Agreement ''power networks and environment'' 2001-2003; Accord ''reseaux electriques et environnement'' 2001-2003

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-01-01

    This agreement, discussed between the French government and Electricite de France (EdF) group, proposes some engagements for the 2001-2003 era for a better environmental integration of power transmission and distribution networks. The agreement is made of two parts: 1 - public distribution networks: realization of new workmanship (medium and low voltage power lines, new lines in dense urban areas), actions on existing workmanship (consequences of December 1999 storms, aesthetical aspects, burial of the main overhead lines in wooded areas, reinforcement of EdF's environmental commitment, remedial actions for environmental 'black points'), general measures of implementation (increasing network safety, protection of birds fauna, coordination of works); 2 - public transportation network (RTE): development and safety improvement of the public transportation network (reinforced arrangement for the establishment of regional development schemes, development of international interconnections, safety improvement of the public transportation network, RTE's environmental plan); line projects (arrangements during projects elaboration, accompanying program); long lived RTE's commitment (environmental management and ISO-14001 certification, vigilance with respect to electromagnetic fields, R and D). (J.S.)

  19. Electrodeposition of ZnO nano-wires lattices with a controlled morphology; Electrodepot de reseaux de nanofils de ZnO a morphologie controlee

    Energy Technology Data Exchange (ETDEWEB)

    Elias, J.; Tena-Zaera, R.; Katty, A.; Levy-Clement, C. [Centre National de la Recherche Scientifique (CNRS), Lab. de Chimie Metallurgique des Terres Rares, UPR 209, 94 - Thiais (France)

    2006-07-01

    In this work, it is shown that the electrodeposition is a changeable low cost method which allows, according to the synthesis conditions, to obtain not only plane thin layers of ZnO but different nano-structures too. In a first part, are presented the formation conditions of a compact thin layer of nanocrystalline ZnO electrodeposited on a conducing glass substrate. This layer plays a buffer layer role for the deposition of a lattice of ZnO nano-wires. The step of nano-wires nucleation is not only determined by the electrochemical parameters but by the properties of the buffer layer too as the grain sizes and its thickness. In this context, the use of an electrodeposition method in two steps allows to control the nano-wires length and diameter and their density. The morphology and the structural and optical properties of these nano-structures have been analyzed by different techniques as the scanning and transmission electron microscopy, the X-ray diffraction and the optical spectroscopy. These studies show that ZnO nano-structures are formed of monocrystalline ZnO nano-wires, presenting a great developed surface and a great optical transparency in the visible. These properties make ZnO a good material for the development of nano-structured photovoltaic cells as the extremely thin absorber cells (PV ETA) or those with dye (DSSC) which are generally prepared with porous polycrystalline TiO{sub 2}. Its replacement by a lattice of monocrystalline ZnO nano-wires allows to reduce considerably the number of grain boundaries and in consequence to improve the transport of the electrons. The results are then promising for the PV ETA cells with ZnO nano-wires. (O.M.)

  20. SOA Challenges for Real-Time and Disadvantaged Grids (Defis de la SOA pour les reseaux defavorises et en temps reel)

    Science.gov (United States)

    2014-04-01

    Par conséquent, l’objectif de l’IST-090 était d’identifier les améliorations à apporter pour que la SOA puisse s’appliquer au niveau tactique, ce qui...STO », « RTO » ou « AGARD » selon le cas, suivi du numéro de série. Des informations analogues, telles que le titre est la date de publication sont...Dairesi Defense Technical Information Center PORTUGAL Başkanlığı 8725 John J. Kingman Road Estado Maior da Força Aérea 06650 Bakanliklar – Ankara

  1. Military Communications with Special Focus on Tactical Communications for Network Centric Operations (Les communications militaires, et plus particulierement les communications tactiques pour les operations reseaux-centrees)

    Science.gov (United States)

    2008-04-01

    Technology Panel (IST) Symposium held in Prague, Czech Republic, on 21-22 April 2008. Published April 2008 Distribution and Availability on Back...caractérisent par une faible largeur de bande, un débit variable, une connectivité peu fiable et des contraintes énergétiques imposées par les canaux radio et...REPORT NUMBER(S) 12. DISTRIBUTION / AVAILABILITY STATEMENT 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS 16

  2. Which available capacity of the grid for renewable energy sources?; Quelle capacite d'accueil des reseaux pour les energies renouvelables?

    Energy Technology Data Exchange (ETDEWEB)

    Bezat, G.; Roy, F. [Reseau de Transport d' Electricite, Dept. Performance du Systeme et Acces au Reseau, 92 - La Defense (France); Busse, Ph. [Reseau de Transport d' Electricite, Dept. Developpement de Reseau et Perspectives Energetiques, 92 - La Defense (France)

    2009-10-15

    The development of renewable energy sources for the generation of electricity, particularly wind energy and solar electricity, implicates to take into account the necessary developments of the electric power transmission network to be able to receive and guarantee the trans-mission of electricity produced from renewable sources which must represent more than 20 % of energy consumption in France in 2020. A transmission grid correctly sized is necessary to reach such targets. The ambitious development of renewable energy sources implicates therefore that the grid problematic is entirely taken into account and that the transmission grid operator has means allowing to locate favor-able zones to this development and to link to these zones an amount of power. Besides, the regulation frame must allow the building of the new electrical lines necessary for the connection of wind farms to the grid, respecting criteria of sustainable development. (authors)

  3. Smart electric grids in the United Kingdom energy strategy; Les reseaux electriques intelligents dans la strategie energetique du Royaume-Uni

    Energy Technology Data Exchange (ETDEWEB)

    Gloaguen, Olivier [Ambassade de France au Royaume-Uni, Service de presse, 58 Knightsbridge, London SW1X 7JT (United Kingdom); Dreyfus, Charles-Antoine [Ecole des Mines de Paris - MINES Paris Tech, 60, Boulevard Saint-Michel 75272 Paris cedex 06 (France)

    2011-09-15

    This study first gives an overview of the current status and limitations of the British power grid. It indicates the British energy mix, describes the network structure and its economic operation (gross and retail market with the bid and offer system, role of the System Operator, ways to increase the electricity production). It presents the energy policy and its regulation framework, outlines the current limitations and challenges (ageing grid, power crunch, de-carbonation challenges). It presents the development of a smart grid as a solution to economy de-carbonation challenges: definition of the 'smart grid concept', smart grid development planning (from 2010 to 2050), technological transition associated with smart electric grid development (a cleaner but more intermittent and random electricity production, better use of fossil fuels, electric energy storage, consequences for the grid, introduction and effects of smart meters). It describes the new associated economic model: evolution of the value chain, financial challenges (required investments, expected benefits, subsidies), new regulation system. It addresses the strategic challenges and the various uncertainties (notably in terms of consumption, privacy issue in relation with the use of smart meters, and project implementation).

  4. Artificial neural networks, a new alternative to Monte Carlo calculations for radiotherapy; Les Reseaux de Neurones Artificiels, une nouvelle alternative aux calculs Monte-Carlo pour la radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Martin, E.; Gschwind, R.; Henriet, J.; Sauget, M.; Makovicka, L. [IRMA/Enisys/FEMTO-ST, Pole universitaire des Portes du Jura, place Tharradin, BP 71427, 2521 1 - Montbeliard cedex (France)

    2010-07-01

    In order to reduce the computing time needed by Monte Carlo codes in the field of irradiation physics, notably in dosimetry, the authors report the use of artificial neural networks in combination with preliminary Monte Carlo calculations. During the learning phase, Monte Carlo calculations are performed in homogeneous media to allow the building up of the neural network. Then, dosimetric calculations (in heterogeneous media, unknown by the network) can be performed by the so-learned network. Results with an equivalent precision can be obtained within less than one minute on a simple PC whereas several days are needed with a Monte Carlo calculation

  5. Loco-regional networks of qualified people in radioprotection: a necessary tool; Les reseaux loco-regionaux de PCR: un outil necessaire

    Energy Technology Data Exchange (ETDEWEB)

    Barbey, P.; Colin, J. [Caen Univ. Basse-Normandie, Service de Radioprotection, 14 (France); Briand-Champlong, J. [Societe Francaise de Radioprotection (SFRP), Presidente de la section PCR, 92 - Fontenay-aux-Roses (France)

    2009-01-15

    Protection against radiation, in France, partly rests on 'qualified people in radioprotection' (P.C.R.). The various statutory texts which followed one another let see the evolutions of their functions. Everyday, in their mission, these actors of ground can be confronted with multiple difficulties among which isolation and the difficulty in preserving a good level of knowledge are often advanced. To organize these actors of radiation protection at the local or regional level in flexible networks to implement is one of the means of answering these difficulties. Several of these networks are already made up or in the course of formation and the current experience feedback of the Great-West network underlines the interest and the need for reinforced this approach to collectively appropriate a real culture of radioprotection. French radiation protection society (S.F.R.P.) supports these networks by associating them with the P.C.R. congress which it organizes every two years and by its action near the P.C.R. certified trainers. (author)

  6. Climatic changes and drainage networks. Which evolutions for tomorrow?; Changements climatiques et reseaux d'assainissement. Quelles adaptations pour demain?

    Energy Technology Data Exchange (ETDEWEB)

    Laplace, D. [Seram, 13 - Marseille (France); Guignard, J.Y. [Astee, 75 - Paris (France); Planton, S. [Meteo France, Centre de Recherches Meteorologiques, 31 - Toulouse (France); Guivarch, J.Y. [DEA Cumpm, 13 - Marseille (France)

    2008-07-01

    The authors propose to evaluate the consequences of the climatic change on the design and the management of drainage networks, more specially in the framework of the revision of the technical instruction of 1977, by the Astee. In concrete terms the main effects will occurs on H{sub 2}S formation, sensitivity of receptors areas, and for coastal towns on the sea-spillways level and the swimming water quality. The impacts of the rains evolutions are also discussed. (A.L.B.)

  7. Sur l'integration de mecanismes d'ordonnancement et de communication dans la sous-couche mac de reseaux locaux temps-reel

    OpenAIRE

    Carvalho, Francisco Vasques de

    1996-01-01

    Dissertation présentée au Laboratoire d'Analyse et d'Architecture des Systèmes du CNRS en vue de l'obtention du titre de Docteur de l'Université Paul Sabatier de Toulouse, spécialité: Informatique Industrielle

  8. Networks of power: historical power annals, No 2; L'electricite en reseaux - networks of power: annales historiques de l'electricite, No 2

    Energy Technology Data Exchange (ETDEWEB)

    Caron, F.

    2004-07-01

    In DEcember 2003, the Electricite de France (EdF) foundation and the house of human sciences of Aquitaine organized a colloquium to celebrate the 20. anniversary of the publication from Thomas P. Hughes entitled: 'networks of power: electrification in western society 1880-1930'. This book, which has become a major reference, represents a fundamental step in the historiography devoted to electric power history. About 15 specialists from the US and Europe have made a link between their researches and Hughes' theories. The choice of the topics has been made according to the subjects tackled in 'Networks of power' but the entire freedom has been given to each participant in the way to treat them. The concepts used by the US searcher have retained the attention, in particular those of 'system', 'technological momentum' and 'reverse salient'. At the same time, and in order to not limit the analysis of the electric power industry to its technical aspects, several participants have considered also the human, managerial and financial networks aspect. Some others have reexamined Hughes' theories using the present day regulation and deregulation notions. Finally, the same theories have been analyzed considering the complex links between electricity and culture. The publication of the articles of this colloquium is not only a tribute to the great US historian Thomas P. Hughes, but also the opportunity to propose an overview of the richness of the works carried out both in Europe and in the US about the 'networks' notion. (J.S.)

  9. Parallelization of learning problems by artificial neural networks. Application in external radiotherapy; Parallelisation de problemes d'apprentissage par des reseaux neuronaux artificiels. Application en radiotherapie externe

    Energy Technology Data Exchange (ETDEWEB)

    Sauget, M

    2007-12-15

    This research is about the application of neural networks used in the external radiotherapy domain. The goal is to elaborate a new evaluating system for the radiation dose distributions in heterogeneous environments. The al objective of this work is to build a complete tool kit to evaluate the optimal treatment planning. My st research point is about the conception of an incremental learning algorithm. The interest of my work is to combine different optimizations specialized in the function interpolation and to propose a new algorithm allowing to change the neural network architecture during the learning phase. This algorithm allows to minimise the al size of the neural network while keeping a good accuracy. The second part of my research is to parallelize the previous incremental learning algorithm. The goal of that work is to increase the speed of the learning step as well as the size of the learned dataset needed in a clinical case. For that, our incremental learning algorithm presents an original data decomposition with overlapping, together with a fault tolerance mechanism. My last research point is about a fast and accurate algorithm computing the radiation dose deposit in any heterogeneous environment. At the present time, the existing solutions used are not optimal. The fast solution are not accurate and do not give an optimal treatment planning. On the other hand, the accurate solutions are far too slow to be used in a clinical context. Our algorithm answers to this problem by bringing rapidity and accuracy. The concept is to use a neural network adequately learned together with a mechanism taking into account the environment changes. The advantages of this algorithm is to avoid the use of a complex physical code while keeping a good accuracy and reasonable computation times. (author)

  10. Information Services: Their Organization, Control and Use.

    Science.gov (United States)

    1981-01-01

    terminal d’ordinoteur connoct6 par los reseaux de t6l~itransmission do donnees ot utilis6, on un premier temps par un inginieur puis par un ing~nieur...penmis d’itro presents aupr~s des profossionnels du batimont pour r~pondre 6 leurs pr~ocupations. L’UTILISATION DES RESEAUX DE TELETRANSMISSIOk4 DE D OW...sur cos diffents reseaux . Serveur, qu’est-co quo ceo veut dire ? Cola veut dire quo natro ordinatour est raccord6 au reau TRANSPAC et au rdseau

  11. The role of electric grids in the European energy policy. Grids development is necessary to supply cleaner and securer electric power; Le role des reseaux electriques dans la politique energetique europeenne. Une evolution des reseaux est indispensable a la fourniture d'une electricite plus propre et plus sure

    Energy Technology Data Exchange (ETDEWEB)

    Merlin, A.

    2009-07-01

    The world is actually entering a new energy era where CO{sub 2} emissions must be reduced. Consequently, the European Union policy includes three goals: a) to reduce greenhouse gas emissions and fossil energy consumption; b) to improve the security of energy supply; c) to improve interconnection between regions. In this context, electrical grids play a strategic role. While the overall energy consumption in Europe will decrease, the electricity demand will increase by more than 1% per year. A large part of this increase will be covered by renewable energy sources, especially wind energy. In 2020 the total wind power installed in Europe should be {approx}1000 GW, leading to a mean power production of 200-250 GW. This makes necessary an adaptation of electrical grids in order to be able to integrate into the system large power sources of intermittent character, and also to improve the solidarity of the different countries. The interconnection of the grids must be improved in order to balance electricity supply and demand. For the transport of electricity over large distances, developments will take place in three different areas; a) high voltage alternative current for most of the grids; b) high voltage direct current where it is necessary to overpass obstacles (mountains, sounds); c) gaseous insulation technology for underground transport. Local (mostly low voltage) grids must also be adapted: so far, they only carry electricity in one direction, to the customers. With the distributed power production, electricity transport in the reverse direction must also be considered.

  12. Financing of networks extension since the 'urbanization and dwelling' law from July 2, 2003. Status of the participation to roads and networks financing; Le financement des extensions de reseaux depuis la loi urbanisme et habitat du 2 juillet 2003. Le point sur la participation pour le financement de la voirie et des reseaux (PVR)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-10-01

    This document aims at giving to readers a general analysis of the new system of financial participation for roads and networks construction (in particular water, sewage and energy networks). About the invoicing of extension costs for power and natural gas networks, an inter-ministry by-law must precise the general principles of the calculation of the contribution given by extension demanders to power distribution network managers when those are the project owners. (J.S.)

  13. The local-regional networks of radiation protection experts: a necessary tool to strengthen; Les reseaux de PCR: Les reseaux loco-regionaux de PCR: un outil necessaire a renforcer - La vie d'un reseau de PCR: l'APCRAP - Sud-Ouest

    Energy Technology Data Exchange (ETDEWEB)

    Barbey, P. [IMOGERE IBFA, Service de Radioprotection, Universite de Caen Basse-Normandie, 14 - Caen (France); Boirie, G. [Hopital Beaujon, 92 - Clichy (France); Barret, Ch. [GH Pitie-Salpetriere, Sevice Competent en Radioprotection, 75 - Paris (France); Barrey, N. [CHU de Bordeaux, 33 (France)

    2008-07-01

    After having recalled the evolution of the legal framework concerning radioprotection and the origin, role and training of the radiation protection experts (PCR in French for Personne Competente en Radioprotection), the author describes the difficulties faced by a PCR on a daily basis. Then, he outlines the interest of a development of local-regional networks between these professionals to promote information transmission and exchange, knowledge updating and so on, and even also to break the isolation of the PCR. He indicates the main objectives of these networks and evokes perspectives, notably after the professional meetings which have been and still are organized twice a year. Two additional and short papers briefly describe the life of one of these networks (the APCRAP, Association des personnes competentes en radioprotection de l'Assistance Publique, association of radiation protection experts belonging to public care services) and briefly present the objectives of the south-western network

  14. Performance Evaluation of Decisionmaking Organizations,

    Science.gov (United States)

    1987-07-01

    8217 Lecture Notes in Decision Systems, MIT, Cambridge, MA. Computer Science, No. 52, Springer-Verlag, Berlin, pp. 302-310. [9] BraMs, G.V. (1983). Reseaux ...theory and lea Reseaux de Petri,’ Technique et Science the modeling of systems, Prentice-Hall, Informatiques, Vol. 4, No. 1, Dunod, France, Englewood Cliffs. NJ. pp. 103-112. . . . I I’ y I F p

  15. Economic assessment group on power transmission and distribution networks tariffs; Groupe d'expertise economique sur la tarification des reseaux de transport et de distribution de l'electricite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-06-01

    Facing the new law on the electric power market liberalization, the french government created an experts group to analyze solutions and assessment methods of the electrical networks costs and tariffs and to control their efficiency. This report presents the analysis and the conclusions of the group. It concerns the three main subjects: the regulation context, the tariffing of the electric power transmission and distribution (the cost and efficiency of the various options) and the tariffing of the electric power supply to the eligible consumers. The authors provide a guideline for a tariffing policy. (A.L.B.)

  16. SEE electric systems. The electricity market opens up. New challenges in metering; SEE reseaux electriques. L'ouverture du marche de l'electricite. Un nouveau defi pour le comptage

    Energy Technology Data Exchange (ETDEWEB)

    Bergerot, J.L. [Electricite de France (EDF), 75 - Paris (France); Doulet, A.; Delorme, G. [EDF-GDF Services, 33 - Bordeaux (France). Groupe d' appui et d' assistance gaz] [and others

    2001-07-01

    The application of the European Directive on the opening up of the energy market redefines the role of companies involved in the production, transmission and distribution of electricity so that eligible customers can henceforth take advantage of the opportunities presented by a genuine market. During this conference managers of transmission and distribution networks will explain the actions they intend to put into place to fulfill their mission. Eligible customers will express their expectations in terms of the market transparency, real prices and contract periods as well as explaining their requirements relating to the quality of electricity and service. Electricity suppliers will indicate the fields in which they aim to differentiate their offer, starting with a product which until now seemed banal. A foreign network manager will share his recent experiences, as regards all of these points. Finally, the constructors will show how traditional metering will evolve to become the management tool to monitor the complex relationships between all the players in the electricity market. (authors)

  17. The strategic role of power grids in the implementation of a European energy policy; Le role strategique des reseaux electriques dans la mise en oeuvre d'une politique energetique europeenne

    Energy Technology Data Exchange (ETDEWEB)

    Merlin, A. [Conseil International des Grands Reseaux Electriques (CIGRE), 75 - Paris (France)

    2010-02-15

    With the development of low carbon and renewable energies, the World is living a third energy revolution. In this new context, the European Union has adopted an ambitious energy policy with a triple objective: reducing the volume of carbon dioxide emissions in the atmosphere in order to fight against a possible disastrous climatic change, increasing the security of its energy supplies by limiting its fossil fuels dependence and by reinforcing the solidarity between member states in particular during crisis situation, and completing the building up of domestic electricity and gas markets by a better integration of these markets at the European scale and in relation with neighboring areas (Mediterranean region, Russia). This article explains the key of success of such a policy: a prominent part of electricity in the European energy mix, with a strategic role given to power grids.

  18. Performance of natural gas distribution networks during the Kocaeli earthquake - 17 august 1999; Comportement des reseaux de distributions de gaz naturel lors du tremblement de terre de Kocaeli 17 aout 1999

    Energy Technology Data Exchange (ETDEWEB)

    Zarea, M.; Adrien, M. [Gaz de France (GDF), 75 - Paris (France)

    2000-07-01

    The Kocaeli (Izmit) earthquake struck recently, on August 17, 1999, a well developed area of Turkey. This earthquake, of a magnitude 7.4 on the open Richter scale, severely damaged numerous buildings, industrial infrastructure, and made a lot of victims. In this context, most attention is given to issues like: seismology (why and how did it happen, what will happen next, etc.), seismic design and construction (why buildings collapsed and how to avoid this in the future). Some other subjects get less attention, because their direct influence in the overall damage is smaller. The behaviour of 'lifelines', designating all the networks which contribute to 'modern' lifestyle: water, energy, communications, etc., belong to this category. Nevertheless, the performance of lifelines during such strong earthquakes is also important, because they can contribute to minimise its impact. This impact has its usual two aspects: integrity and operability. For instance, the integrity requirement means that failures of the considered lifeline due to the earthquake should not directly affect property and life. The operability requirement means that a given subset of the lifeline remains operational, in order to fulfill vital tasks. We propose here a brief analysis of the performance of two relatively recently commissioned gas distribution systems: IZGAZ in Izmit, close the epicenter, and IDGAS in Istanbul. They have the advantage of representing a large sample of a recent implementation of the PE (polyethylene) technique, which has reached maturity. Both are cases of the Gaz de France 4 bar PE technology transferred to a Turkish operator, who completely managed the crisis. The first part describes the two networks, both their high medium pressure steel network, regulators, and the intermediate PE network, finishing with service lines and boxes. Then, the damage reported by the operational teams and their very important shut-down and blowdown actions are summarised. The rapid personnel mobilization in critical conditions played an important role in keeping the community harmless. No evidence of fire due to gas leaks and only a very limited damage to the network was registered. The good overall performance of these gas distribution systems showed the importance of managing the whole chain: from design to components, construction, commissioning, operation, maintenance and crisis management and communication. Some crisis management and communications issues are touched, pin-pointing the vital role played by a reliable and autonomous communications system. The procedures to return to service and the customers' reactions are also dealt with. The involvement of the municipal gas operators in humanitarian aid to people left homeless by the earthquake is also part of these operators' commitment. Finally, a lot of lessons could be learnt from this event, although the overall performance was very satisfactory. They are the proof that there is always room for improving a good technique and good operational standards, in order to give customers even more confidence in gas distribution for the future. (authors)

  19. Artificial neural networks (ANN's) characterisation of soil pollution: the polycyclic hydrocarbons (PAHs) case study; Contribution des reseaux de neurones artificiels (RNA) a la caracterisation des pollutions de sol. Exemples des pollutions en hydrocarbures aromatiques polycycliques (HAP)

    Energy Technology Data Exchange (ETDEWEB)

    Dan, A.; Oosterbaan, J.; Jamet, Ph. [Ecole Nationale Superieure des Mines, 77 - Fontainebleau (France). Centre d' Information Geologique

    2002-10-01

    We develop the ANNs (Artificial Neural Networks) method to explore contaminant concentration profiles observed in soils of polluted sites. ANNs are particularly efficient in simultaneous analysis of numerous parameters and in identification of complex relations involving field data. Applying the ANN models on a PAH (Polycyclic Aromatic Hydrocarbon) database, we extracted the most characteristic components of known contaminations and applied it to identify the source type of similar polluted sites. The performed tests prove the generalisation capability of the selected ANN model. (authors)

  20. Numerical modeling of the thermomechanical behavior of networks of underground galleries for the storage of the radioactive waste: approach by homogenization; Modelisation numerique du comportement thermomecanique de reseaux de galeries souterraines pour le stockage des dechets radioactifs: Approche par homogeneisation

    Energy Technology Data Exchange (ETDEWEB)

    Zokimila, P

    2005-10-15

    Deep geological disposal is one of the privileged options for the storage of High Level radioactive waste. A good knowledge of the behavior and properties of the potential geological formations as well as theirs evolution in time under the effect of the stress change induced by a possible installation of storage is required. The geological formation host will be subjected to mechanical and thermal solicitations due respectively to the excavation of the disposal tunnels and the release of heat of the canisters of radioactive waste. These thermomechanical solicitations will generate a stress relief in the host layer and disposal tunnels deformations as well as the extension of the damaged zones (EDZ) could cause local and global instabilities. This work aims to develop calculation methods to optimize numerical modeling of the thermoelastic behavior of the disposal at a large scale and to evaluate thermomechanical disturbance induced by storage on the geological formation host. Accordingly, after a presentation of the state of knowledge on the thermomechanical aspects of the rocks related to deep storage, of numerical modeling 2D and 3D of the thermoelastic behavior of individual disposal tunnel and a network of tunnels were carried out by a discrete approach. However, this classical approach is penalizing to study the global behavior of disposal storage. To mitigate that, an approach of numerical modeling, based on homogenization of periodic structures, was proposed. Formulations as numerical procedures were worked out to calculate the effective thermoelastic behavior of an equivalent heterogeneous structure. The model, obtained by this method, was validated with existing methods of homogenization such as the self-consistent model, as well as the Hashin-Shtrikman bounds. The comparison between the effective thermoelastic behavior and current thermoelastic behavior of reference showed a good coherence of the results. For an application to deep geological storage, the effective thermoelastic properties of a network of circular tunnels could be given in 2D for various dimensions of the distance between galleries. (author)

  1. Numerical simulations of flows through fixed networks of monodispersed and bi-dispersed spheres, for moderate Reynolds numbers; Simulations numeriques d'ecoulements a travers des reseaux fixes de spheres monodisperses et bidisperses, pour des nombres de Reynolds moderes

    Energy Technology Data Exchange (ETDEWEB)

    Massol, A.

    2004-02-15

    The application of statistically averaged two-fluid models for the simulation of complex indus- trial two-phase flows requires the development of adequate models for the drag force exerted on the inclusions and the interfacial heat exchange. This task becomes problematic at high volume fractions of the dispersed phase. The quality of the simulation strongly depends upon the inter- facial exchange terms, starting with the steady drag force. For example, an accurate modelling of the drag force is therefore a crucial point to simulate the expansion of dense fluidized beds. Most models used to study the exchange terms between particles and fluids are based on the interaction between an isolated particle and a surrounding gas. Those models are clearly not adequate in cases where the volume fraction of particles increases and particle-particle interactions become important. Studying such cases is a complex task because of the multiple possible configurations. While the interaction between an isolated sphere and a gas depends only on the particle size and the slip velocity between gas and particles, the interaction between a cloud of particles and a gas depends on many more parameters: size and velocity distribution of particles, relative position of particles. Even if the particles keep relative fixed positions, there is an infinite number of combinations to construct such an array. The objective of the present work is to perform steady and unsteady simulations of the flow in regular arrays of fixed particles in order to analyze the influence of the size and distributions of spheres on drag force and heat transfer (the array of spheres can be either monodispersed, either bi-dispersed). Several authors have studied the drag exerted on the spheres, but only for low Reynolds numbers and/or solid volume fractions close to the packed limit. Moreover some discrepancies are observed between the different studies. On top of that, all existing studies are limited to steady flows, and do not deal with heat transfer and poly-dispersion. First of all, the steady viscous drag exerted on the spheres of face-centered cubic, simple cubic and tetragonal arrays is evaluated. This allows to analyze the influence of the spheres distribution and solid volume fraction on drag coefficient. Next, the influence of Reynolds number and solid volume fraction on heat transfer from spheres to the surrounding fluid in face-centered cubic arrays is studied. Finally, the history effects on the total force exerted on the inclusions and on the heat transfer between the inclusions and the surrounding fluid are studied. (author)

  2. Modeling by artificial neural networks. Application to the management of fuel in a nuclear power plant; Modelisation par reseaux de neurones. Application a la gestion du combustible dans un reacteur

    Energy Technology Data Exchange (ETDEWEB)

    Gaudier, F

    1999-07-01

    The determination of the family of optimum core loading patterns for Pressurized Water Reactors (PWRs) involves the assessment of the core attributes, such as the power peaking factor for thousands of candidate loading patterns. Despite the rapid advances in computer architecture, the direct calculation of these attributes by a neutronic code needs a lot of of time and memory. With the goal of reducing the calculation time and optimizing the loading pattern, we propose in this thesis a method based on ideas of neural and statistical learning to provide a feed forward neural network capable of calculating the power peaking corresponding to an eighth core PWR. We use statistical methods to deduct judicious inputs (reduction of the input space dimension) and neural methods to train the model (learning capabilities). Indeed, on one hand, a principal component analysis allows us to characterize more efficiently the fuel assemblies (neural model inputs) and the other hand, the introduction of the a priori knowledge allows us to reducing the number of freedom parameters in the neural network. The model was built using a multi layered perceptron trained with the standard back propagation algorithm. We introduced our neural network in the automatic optimization code FORMOSA, and on EDF real problems we showed an important saving in time. Finally, we propose an hybrid method which combining the best characteristics of the linear local approximator GPT (Generalized Perturbation Theory) and the artificial neural network. (author)

  3. Distributed power generation impact on power distribution networks - Current status and recommended proposals; Impact de la production decentralisee sur les reseaux de distribution. Analyse de la situation et proposition de solutions

    Energy Technology Data Exchange (ETDEWEB)

    Nibbio, N.; Chollet, Ph. [Romande Energie, Morges (Switzerland); Kneuss, A.; Sauvain, H. [EIA-FR, Fribourg (Switzerland)

    2010-07-01

    This article takes a look at the new situation created in the power distribution network of a Swiss electricity utility by increasing numbers of distributed power generators, especially from renewable energy sources. To limit energy losses and maintain the grid stability, in particular the voltage within the required range, data have to be continuously collected from remote locations in the network and transmitted to a control centre that take actions. One main possible action is the injection of reactive power by means of large capacitors. The article describes a case study considering one particular section of the company's network and a 5 MW wind park.

  4. Less power outages thanks to shunt circuit breakers - Basic principle and experience gained in medium voltage networks with isolated neutral; Reduction des interruptions de fourniture grace au disjoncteur shunt. Principe et experimentation dans les reseaux moyenne tension a neutre isole

    Energy Technology Data Exchange (ETDEWEB)

    Raemy, E. de; Dutoit, J.

    2009-07-01

    The article presents the basic principle of the operation of shunt circuit breakers and reports on two years experience with such devices in the medium voltage (20 kV) distribution networks with isolated neutral of the 'Groupe E' electric utility in Western Switzerland. Shunt circuit breakers are devices that absorb the current of a phase for a few seconds in case this phase conductor encounters an insulation failure to the ground. In this way, electric arcs may be interrupted before they cause short circuits and, consequently, power outages. This is particularly useful in cable distribution networks. The article reports on the sophisticated criteria used to identify the default phase, since a simple criterion based on the voltage difference to the ground may be misleading. The experiments made in the networks under operation are reported in detail. They included all possible types of insulation failures that may occur in the practice. The statistics of the real failures encountered in the following two years of operation and the experience gained are also discussed. The authors conclude that shunt circuit breakers effectively avoid most power outages. The 'Groupe E' utility decided to immediately install such devices in its networks.

  5. Local-regional networks of persons with abilities in radioprotection and other actors in radioprotection. Audit report; Les reseaux loco-regionaux de personnes competentes en radioprotection et autres acteurs de la radioprotection. Rapport d'audit

    Energy Technology Data Exchange (ETDEWEB)

    Lefaure, Ch.

    2009-03-15

    As the regulation requires the existence of persons with abilities in radioprotection (PCR, personnes competentes en radioprotection) in many industrial, medical or research activities where ionizing radiations are present, in order to improve worker protection, these professionals who are much less acknowledged in these sectors than in the nuclear sector, felt the need to gather in regional and sector-based networks. This report proposes a presentation of three existing networks (the APCRAP, the Grand-Ouest network, and the Aquitaine-Sud-Ouest network). For each of them, the report addresses the following aspects: creation, objectives, statutes, members, activities, human, technical and financial resources, role. Then answers to a survey and to interviews are analyzed with respect to the professional sector and to the region, in terms of expectations towards the networks, and in terms of network operation and services. Interviews of institutional actors and union and management representatives are also analysed

  6. Distribution power system reliability assessment using Monte Carlo simulation: optimal maintenance strategy application; Evaluation de la surete de fonctionnement des reseaux de distribution par la simulation Monte Carlo: application a des strategies de maintenance optimales

    Energy Technology Data Exchange (ETDEWEB)

    Ocnasu, A.B.

    2008-10-15

    Today, the electricity sector is confronted with new challenges imposed by the deregulation of the electricity market, the international desire to reduce the greenhouse gases emissions, the development of new technologies. There is an increasing need to assess the reliability of the distribution systems. We can see a migration of methods specially used at transmission level to the distribution level. In a previous PhD, a method based on a sequential Monte Carlo simulation has been developed. The first part of this thesis deals with the study of acceleration methods. Two methods were tested, Antithetic Variates and Stratification. The best acceleration was achieved by a combination of these two methods. Then, we discussed the feasibility study of an optimization method based on reliability criteria. The chosen application was the preventive maintenance strategies optimization. We looked for the optimal number of preventive maintenance and the maximum value of failure rate when maintenance is carried out, minimising the total cost (cost of preventive maintenance, corrective maintenance and the cost of interruptions). In the end, a series of reflections related to the future development of a reliability analysis tool were presented. A modular structure of the tool is proposed to facilitate its use, and the possibility of parallel calculations for a better efficiency. (author)

  7. Large-scale management of electric grids - Power flux control in an electric network; Gestion des reseaux electriques a grande echelle. Controle des flux de puissance d'un reseau electrique

    Energy Technology Data Exchange (ETDEWEB)

    Lalou, M. J. [EIA-FR, Fribourg (Switzerland); Affolter, J.-F. [HEIG-VD, Yverdon-les-Bains (Switzerland)

    2010-07-01

    Security of supply in electricity networks is a major industrial challenge for the future. It involves power generation, transmission and distribution altogether. Networks gradually approach saturation. This article presents an optimal real-time management method of power flux in an electricity network equipped with FACTS and phase measuring devices. FACTS have to be gradually introduced, however not earlier than in 10 years time, as the reliability of data transmission for their control is currently not high enough, considering the order of magnitude of the involved electric power.

  8. Network inter-connectivity and capacity reservation behaviour: an investigation of the Belgian gas transmission network; Interconnexion des reseaux et comportement de capacite de reservation: une etude du reseau Belge de transport de gaz

    Energy Technology Data Exchange (ETDEWEB)

    Cuijpers, Ch.; Woitrin, D. [Commission for Electricity and Gas Regulation (CREG) (Belgium)

    2009-01-15

    Lack of cross-border integration explains largely why natural gas markets remain basically national in scope, with levels of concentration similarly high as when the liberalization process commenced. This paper presents the results of an assessment of the upstream/downstream capacity of the Belgian natural gas transmission network which is highly interconnected with adjacent networks and fosters important transit activities. It is shown that the tendency to a better market coupling still suffers from important mismatches of capacity provisions on both sides of cross-border interconnections. Moreover, shippers use gas transmission networks more and more from a commercial portfolio perspective which goes beyond the traditional security of supply purpose of network designs. Capacity booking rates appear to be significantly higher than the underlying physical gas flows. From these findings, the paper contributes to a better understanding of the market barrier created by contractual congestion at cross-border interconnection points. The paper argues that contractual congestion is a symptom of suboptimal cooperation of adjacent network operators and lack of effective mechanisms to bring booked but non-used capacity back to the market, rather than an indicator for an overall need to increase investment budgets. (authors)

  9. The radioactivity measurement in the Loire catchment basin. Actors, networks, data inventory; La mesure de la radioactivite dans le bassin versant de la Loire. Acteurs, reseaux, inventaire des donnees

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    The objective of this report on the Loire watershed was to broaden at all the nuclear installations of the watershed the method of synthesis made for Saint-Laurent-des-Eaux nuclear power plant, by resting on the whole of actors doing the radioactivity measurements in environment. This report shows that these actors are numerous. The measurement plans implemented have for objective to establish the radiological situation of environment, near or not the nuclear facilities, to detect the abnormal increase of radioactivity, to evaluate the exposure of populations to the ambient radioactivity, or to check the conformity of practices (nuclear activities) and products. This assessment enlightens the lack of a real global strategy in the organisation of the radioactivity measurement at the level of the watershed. The inventory of available data for the Loire watershed allowed to show the diversity of measurements realised. The I.R.S.N. is face to a complex situation of data return in the frame of the implementation of an information system of the national network of radioactivity measurement in environment. (N.C.)

  10. Application of neural networks to measurement methods based on radiation interactions with matter; Application des reseaux de neurones aux methodes de mesure basees sur l'interaction rayonnement matiere

    Energy Technology Data Exchange (ETDEWEB)

    Pilato, V

    1999-07-01

    The possibility of improving by neuronal techniques the preparation and interpretation of nuclear measurements was investigated. A general methodology was developed and applied to various problems in this field. Whatever the problem to be treated, to solve it comes to determine the relation which binds the inputs to the outputs. Neural networks based on supervised training, like the multilayer Perceptron, have the capability to calculate any relation between a set of input and output data. On the other hand, the training phase is often a long and delicate operation whose difficulties grow with the size of the network:it is thus interesting to reduce it by introducing knowledge a priori and/or by reducing the number of inputs in order to extract the relevant information. If the correlations between the inputs are linear, the Principal Components Analysis (PCA) and its neuronal equivalents make it possible to obtain by orthogonal projection a reduced number of input components while preserving the maximum of initial information. If the correlations are nonlinear, the Curvilinear Components Analysis (CCA) allows, by a unsupervised training, to carry out a nonlinear projection of the inputs in a space of reduced size. Besides, it is noticed that when the dimension of the input space is equal to the intrinsic dimension of the problem, this last is practically solved by CCA. We propose a general method which consists in characterizing as well as possible the problem by its inputs and then to extract and classify the information contained in those by projection in a space of reduced size. Association between the projected data and the problem outputs is then carried out by a supervised training network. Certain results having to be provided with their associated uncertainty, a statistical method based on the bootstrap algorithm is proposed. Potential applications other that those treated are considered. (author)

  11. Information manual for the experimentation of the deployment of optical fibers on public power distribution networks; Notice d'information pour l'experimentation du deploiement de fibres optiques sur les reseaux publics d'electricite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    During the French inter-ministry committee for the national development (CIADT) of July 9, 2001, the government decided to launch a feasibility study about the deployment of telecommunication optical fibers over the whole territory using the electricity transportation grid. The aim is to give access to high-speed Internet to everyone and at a reasonable cost. This manual summarizes the technical, legal and economical results of the study carried out by the working group: 1 - the actors in concern (managers of power transportation and distribution networks, country authorities, managers and users of telecommunication infrastructures, regulatory agencies, financial organizations); 2 - the telecommunication networks on power lines; 3 - the feasibility of the experimentation (relations between the different partners, conditions); 4 - the implementation of the experimentation (useful contacts, contracts); 5 - the experimentation areas. Appendixes. (J.S.)

  12. Awareness of Emerging Wireless Technologies: Ad-hoc and Personal Area Networks Standards and Emerging Technologies (Sensibilisation a l'emergence des technologies sans fil: technologies emergeantes et normes de reseaux personnels et ad-hoc)

    National Research Council Canada - National Science Library

    Stassinopoulos, George; Boucher, L; Churavy, M; Plesse, T; Marquart, D; Kyriazakos, S; Papaoulakis, N; Nikitopoulos, D; Maseng, T

    2007-01-01

    .... The report starts with ad-hoc networking concepts and maturing technological solutions. Ad-hoc networking is a necessary companion to wireless communication, due to the inherent lack of reliability of any wireless based link level protocol...

  13. The tariffs of use of liquefied natural gas transportation networks and facilities; Les tarifs d'utilisation des reseaux de transport et des installations de gaz naturel liquefie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    The new tariff proposals for the use of natural gas transportation networks were transmitted to the French Ministry of economy, finances and industry on October 27, 2004 by the commission of energy regulation. These proposals have been adopted and are the object of three legislative texts: the decree no. 2005-607 from May 27 2005 relative to the tariffing rules, the by-law from May 27, 2005 relative to the definition of balancing areas, and the advice from May 27, 2005 relative to the tariffs of use of natural gas transportation networks. In application of article 7 of the law from January 3, 2003, the implementation of the first tariffs of use of natural gas transportation networks and of liquefied natural gas (LNG) facilities is defined in the decree no. 2004-994 from September 21, 2004. On the main transportation network, the tariffing is of 'input-output' type and does not depend on the distance, while at the regional network scale, the tariffing is linked with the distance. The tariff of use of LNG facilities is the sum of 4 terms: a fixed term applied to each batch unloaded at the methane terminal, a term proportional to the unloaded LNG quantities, a term depending on the duration of use of LNG storage facilities and a term covering the gas consumptions of LNG facilities. This document gathers these different legislative texts with their appendixes. (J.S.)

  14. Awareness of Emerging Wireless Technologies: Ad-hoc and Personal Area Networks Standards and Emerging Technologies (Sensibilisation a l’emergence des technologies sans fil: technologies emergeantes et normes de reseaux personnels et ad-hoc)

    Science.gov (United States)

    2007-04-01

    rubrique PAN (réseaux personnels). Ces technologies, avec un accent sur une faible alimentation , doivent être également vues dans le contexte d’une...the smart healthy home, the professional environment and the fancy futuristic multimedia traveler. Corresponding environment for military

  15. Conference Proceedings of International High Speed Networks for Scientific and Technical Information, Held at Ottawa, Canada on 6-7 October 1993 (Les Reseaux Internationaux Rapides D’Echange D’Information Scientifique et Technique)

    Science.gov (United States)

    1994-02-01

    y "Cb Dr Maria Cruz Gutierref Cwid Div. de Materiales y Estructuras NASA Sciadailc and Technical INTA Jatormadan Pmgram Crta. Torrejon a Ajalvir, Km...not for authors. Superior de Investigaciones Cientificas (CSIC) in And it was emphasized that the copyright problem Madrid, examined some of these... INVESTIGACIONES CIENTIFICAS (CSIC) Centro T’cnico de InformAtica Pinar 19 28006 Madrid Spain E-mail: castelo@cti.csic.es 1. ABSTRACT This paper

  16. Multi-criteria choices in risk and multi-dimensional variables: method proposal and application to energy transportation networks; Choix multicriteres dans le risque et variables multidimensionnelles: proposition de methode et application aux reseaux de transport d'energie

    Energy Technology Data Exchange (ETDEWEB)

    Munier, B. [Ecole Normale Superieure, Groupe de Recherche sur le Risque, l' Information et la Decision (GRID), 94 - Cachan (France); Taverdet-Popiolek, N. [Ecole Superieure de Commerce de Rouen, 76 - Mont-Saint-Aignan (France); Institut Universitaire de Technologie, 92 - Sceaux (France)

    1999-07-01

    This paper presents an application of Multiple attribute utility theory on strategic choices concerning energy transformation. The environmental assessment of a network reinforcement strategy is emphasized. Our assessment brings about to consider multidimensional variables in MCDM. However, Multi-Attributed Utility Theory (MAUT) cannot, as a practical matter, manage such variables. We therefore work out a methodology to transform multidimensional variables into unidimensional ones. We apply it then to a practical case. From the application, we draw some conclusions on Multi-Attributed Utility Theory and out its interest for strategic choices dealing with environmental consequences. (authors)

  17. Materials and Process Specifications and Standards

    Science.gov (United States)

    1977-11-01

    factors involved in setting standards of this type are social (which usually predominates), legal, political, and then, to a lesser extent, economic, and...regulatory agencies. Material and process specifications are obviously affected by these relatively new social forces and, in turn, may...Welding Society Basic Standardization Agreement Conference Internationale des Grands Reseaux Internationale (International Conference on Large High

  18. Eestis loodi CIGRE rahvuslik komitee / Raine Pajo

    Index Scriptorium Estoniae

    Pajo, Raine, 1976-

    2005-01-01

    Rahvusvaheline Suurte Elektrisüsteemide Nõukogu (Conseil International des Grandes Reseaux Electriques) võttis 2005. a. septembris oma 54. liikmeks CIGRE Eesti Rahvusliku Komitee, mis koosneb kümnest kõrgepingealaga seotud asutusest ja ettevõttest. CIGRE eesmärk on arendada ning levitada elektrotehnilist kõrgepingealast oskusteavet

  19. L'interdisciplinarite en sciences sociales pour l'etude du contact des langues (Interdisciplinarity in Social Sciences of the Study of the Relationships of Languages). Proceedings of a Colloquium of the International Center for Research on Bilingualism and the Institute for Interethnic and Intercultural Studies and Research (2nd, Quebec City, Quebec, Canada, October 1-5, 1984).

    Science.gov (United States)

    Prujiner, Alain, Ed.

    Papers given at an international conference applying the social sciences to the study of the relationships of languages include the following: "Reseaux sociaux et comportements langagiers en milieu de contact des langues" ("Social Networks and Language Behaviors in a Language Contact Setting") by M. Blanc and J. Hamers, with…

  20. Structure of extracellular polysaccharide produced by lignin-degrading fungus Phlebia radiata in liquid culture

    Czech Academy of Sciences Publication Activity Database

    Krčmář, P.; Novotný, Čeněk; Marais, M. F.; Joseleau, J. P.

    1999-01-01

    Roč. 24, - (1999), s. 1 ISSN 0141-8130 R&D Projects: GA AV ČR IAA6301501 Grant - others: Reseaux Formation Recherche(FR) 94R0073 Subject RIV: EH - Ecology, Behaviour Impact factor: 1.514, year: 1999

  1. Author Details

    African Journals Online (AJOL)

    Ajavon, SA. Vol 14, No 1 (2012): Series E - Articles Planification optimisee des reseaux electriques par la methode des algorithmes genetiques avec prise en compte uniquement de l'insertion des sources d'energies electriques renouvelables (eolien, solaire photovoltaïque et hydroelectrique) Abstract. ISSN: 2413-354X.

  2. The problem of scattering in fibre-fed VPH spectrographs and possible solutions

    Science.gov (United States)

    Ellis, S. C.; Saunders, Will; Betters, Chris; Croom, Scott

    2014-07-01

    All spectrographs unavoidably scatter light. Scattering in the spectral direction is problematic for sky subtraction, since atmospheric spectral lines are blurred. Scattering in the spatial direction is problematic for fibre fed spectrographs, since it limits how closely fibres can be packed together. We investigate the nature of this scattering and show that the scattering wings have both a Lorentzian component, and a shallower (1/r) component. We investigate the causes of this from a theoretical perspective, and argue that for the spectral PSF the Lorentzian wings are in part due to the profile of the illumination of the pupil of the spectrograph onto the diffraction grating, whereas the shallower component is from bulk scattering. We then investigate ways to mitigate the diffractive scattering by apodising the pupil. In the ideal case of a Gaussian apodised pupil, the scattering can be significantly improved. Finally we look at realistic models of the spectrograph pupils of fibre fed spectrographs with a centrally obstructed telescope, and show that it is possible to apodise the pupil through non-telecentric injection into the fibre.

  3. Initiation and growth of thermal fatigue crack networks in an AISI 304 L type austenitic stainless steel (X2 CrNi18-09); Amorcage et propagation de reseaux de fissures de fatigue thermique dans un acier inoxydable austenitique de type X2 CrNi18-09 (AISI 304 L)

    Energy Technology Data Exchange (ETDEWEB)

    Maillot, V

    2004-07-01

    We studied the behaviour of a 304 L type austenitic stainless steel submitted to thermal fatigue. Using the SPLASH equipment of CEA/SRMA we tested parallelepipedal specimens on two sides: the specimens are continuously heated by Joule effect, while two opposites faces are cyclically. cooled by a mixed spray of distilled water and compressed air. This device allows the reproduction and the study of crack networks similar to those observed in nuclear power plants, on the inner side of circuits fatigued by mixed pressurized water flows at different temperatures. The crack initiation and the network constitution at the surface were observed under different thermal conditions (Tmax = 320 deg C, {delta}T between 125 and 200 deg C). The experiment produced a stress gradient in the specimen, and due to this gradient, the in-depth growth of the cracks finally stopped. The obtained crack networks were studied quantitatively by image analysis, and different parameters were studied: at the surface during the cycling, and post mortem by step-by-step layer removal by grinding. The maximal depth obtained experimentally, 2.5 mm, is relatively coherent with the finite element modelling of the SPLASH test, in which compressive stresses appear at a depth of 2 mm. Some of the crack networks obtained by thermal fatigue were also tested in isothermal fatigue crack growth under 4-point bending, at imposed load. The mechanisms of the crack selection, and the appearance of the dominating crack are described. Compared to the propagation of a single crack, the crack networks delay the propagation, depending on the severity of the crack competition for domination. The dominating crack can be at the network periphery, in that case it is not as shielded by its neighbours as a crack located in the center of the network. It can also be a straight crack surrounded by more sinuous neighbours. Indeed, on sinuous cracks, the loading is not the same all along the crack path, leading to some morphological effect instead of shielding effect. A 2-D finite element modelling of multiple crack propagation has been performed: when the morphological effects are not dominant, there is a good agreement between modelling and experimental results. (author)

  4. Notice no.02-A-05 of the 18 april 2002 relative to the tariffs of the electric power transport and distribution public networks utilization; Avis no.02-A-05 du 18 avril 2002 relatif aux tarifs d'utilisation des reseaux publics de transport et de distribution d'electricite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This notice gives the juridical framework of the future decree concerning the access to the public network of electric power transport and distribution, the principles of the regulation and the project description. It gives also opinions on the competition analysis and its consequences. (A.L.B.)

  5. Assessment of the bioavailability and the transfer of organic and metallic pollutants in 'soil - plant - invertebrate' food webs; Evaluation de la biodisponibilite et des transferts de polluants metalliques et organiques dans les reseaux trophiques ''sols-plantes-invertebres''

    Energy Technology Data Exchange (ETDEWEB)

    Scheifler, R.

    2002-06-15

    Pollution of ecosystems by metallic trace elements (MTEs) and organic compounds may lead to pollutant transfer in food webs. The aim of this work was to improve the assessment of bioavailability, transfer and effects of various MTEs (mainly cadmium (Cd) but also copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn)) and an organic pollutant, the herbicide Isoproturon. The food webs studied in this work were made up of 2 or 3 compartments among the following: soil - primary producer (lettuce Lactuca sativa, colza Brassica napus and maize Zea mays) - primary consumer (snail Helix aspersa) - secondary consumer (carabid beetle Chrysocarabus splendens). Three complementary approaches using food webs of increasing complexity were exploited. The first approach allowed studying pollutant bioavailability and transfers between 2 links of a food chain under controlled conditions. The isotopic dilution technique, until now only used to characterise the phyto-availability of major elements and MTEs in soils, was adjusted for the first time to an animal organism, the snail H. aspersa (assessment of zoo-availability) This work showed that snails, contrarily to plants, accessed the non-isotopically exchangeable Cd pool in soils, considered as non-bio-available by current risk assessment procedures. The study of Cd transfer from plants (B. napus contaminated by surface deposition) to the snail H. aspersa showed a high bioaccumulation of Cd in snail tissues and effects on snail growth and consumption at high concentrations. The bioaccumulation factor (BAF, herein defined as the ratio of the concentration of a pollutant in the tissues of an organism divided by the concentration of this pollutant in its food) was higher than 2. These results suggest that snails inhabiting polluted environments could represent a risk for their predators. To test this hypothesis, the transfer of Cd from contaminated snails to one of their predators, the carabid beetle C. splendens, was studied. Exposure of beetles to the most highly contaminated preys led to a significant increase in mortality (during metamorphosis). Cd concentrations in beetles were very low and much lower than those measured in snail tissues. These results confirmed previous studies, which showed that bio-magnification (increase of a pollutant concentration from one level in a food chain to the upper link) is not a general rule for pollutant transfers in contaminated ecosystems. In a second approach, microcosms were developed to study the transfers in at least three links of a food web. In a first experiment, the transfer of 5 ETMs was studied in the system 'soil (2 agricultural soils: one contaminated and one non-polluted) - plant (lettuce L. sativa) - invertebrate (snail H. aspersa)'. After 4 weeks of exposure, Cd, Zn and Pb concentrations were much higher in the tissues of snails exposed to the polluted soil. Cu concentrations were not different between snails exposed to the polluted soil and those exposed to the non-contaminated one, suggesting MTE regulation by snails. Ni concentrations were higher in snails exposed to the non-polluted soil. The transfer kinetic, which was studied for 2 months in the snails exposed to the polluted soil, showed a regular increase of Cd and Zn concentrations, a rapid increase then a stabilization of Pb concentrations and a regulation of Cu and Ni concentrations. In a second experiment, microcosms were used to study the transfers 'soil - snails', 'maize (Z. mays) - snails' and 'soil - maize - snails' of a {sup 14}C-labelled herbicide, the Isoproturon. The transfer 'soil - snails' was much higher than the transfer 'maize - snails'. Metabolites of Isoproturon were determined in snail tissues. Very small quantities of native Isoproturon were found in snail tissues and the metabolites were mainly unknown residues (i.e. different from those obtained during Isoproturon degradation in soils, plants and microorganisms). The herbicide did not exert toxic effects on snail growth. Finally, a third approach using the microcosms (previously described), allowed the in situ study of the transfer of 5 ETMs from soils amended by sewage sludge to the snail H. aspersa. Amendments did not exert either lethal or sublethal effects on snails. In contrast, a rapid (5 and 7 weeks of exposure) and significant increase of Zn concentrations in snail tissues was showed. In conclusion, the successful adaptation of the isotopic dilution technique to H. aspersa snails should improve the assessment of ETM bioavailability to soil invertebrates (zoo-availability). The transfer experiments made in this work contribute to a better knowledge of pollutant transfer routes in a 'soil - plant - primary consumer - predator' food web. In addition, the microcosms developed in this work constitute a new tool for evaluating the risk of pollutant transfer in food webs. (author)

  6. Study, design and realization of a fault-tolerant and predictable synchronous communication protocol on off-the-shelf components; Etude, conception et mise en oeuvre d'un protocole de communication synchrone tolerant aux fautes et predictible sur des composants reseaux standards

    Energy Technology Data Exchange (ETDEWEB)

    Chabrol, D

    2006-06-15

    This PhD thesis contributes to the design and realization of safety-critical real-time systems on multiprocessor architectures with distributed memory. They are essential to compute systems that have to ensure complex and critical functions. This PhD thesis deals with communication media management. The communication management conditions strongly the capability of the system to fulfill the timeliness property and the dependability requirements. Our contribution includes: - The design of predictable and fault-tolerant synchronous communication protocol; - The study and the definition of the execution model to have a efficient and safe communications management; - The proposal of a method to generate automatically the communications scheduling. Our approach is based on a communication model that allows the analysis of the feasibility, before execution, of a distributed safe-critical real-time system with timeliness and safety requirements. This leads to the definition of an execution model based on a time-triggered and parallel communication management. A set of linear constraints system is generated automatically to compute the network scheduling and the network load with timeliness fulfillment. Then, the proposed communication interface is based on an advanced version of TDMA protocol which allows to use proprietary components (TTP, FlexRay) as well as standard components (Ethernet). The concepts presented in this thesis lead to the realisation and evaluation of a prototype within the framework of the OASIS project done at the CEA/List. (author)

  7. Intelligent networks: evolution or revolution? Source of energy efficiency or economical optimisation? For who's benefit?; Reseaux intelligents: evolution ou revolution? Source d'efficacite energetique et/ou d'optimisation economique? Au benefice de qui?

    Energy Technology Data Exchange (ETDEWEB)

    Fontaine, Christian

    2010-09-15

    The electricity sector has experienced a slow evolution. Renewable production developments and telecommunications and computers usage will bring major changes with hard to predict effects. Computerized management of production and local storage combined to a certain mastering of the allowed consumption by home automation could improve reliability and the final price for consumers. This change offers great opportunities but also risks of failures, both financial and technical. The regulators have a major role to play in order to understand the concrete gains of the technological propositions and to regulate the investment costs involved. [French] Le secteur de l'electricite a connu une evolution lente. Le developpements des productions renouvelables, l'utilisation des telecommunications et de l'informatique provoquera un bouleversement majeur dont il est difficile de prevoir l'ampleur. La gestion automatisee des productions et stockages locaux combinee a une certaine maitrise de la consommation permise par la domotique pourrait ameliorer la fiabilite et le prix final pour les consommateurs. Ce changement presente de grandes opportunites mais aussi des risques d'echecs, tant financiers que techniques. Les regulateurs ont un role majeur a jouer pour comprendre les gains concrets des propositions technologiques et reguler les couts d'investissement qu'elles impliquent.

  8. Photoemission and photo-field-emission from photocathodes with arrays of silicon tips under continuous and pulsed lasers action; Photoemission et photoemission de champ a partir de photocathodes a reseaux de pointes de silicium sous l`action de lasers continus et pulses

    Energy Technology Data Exchange (ETDEWEB)

    Laguna, M.

    1995-11-01

    The electron machines`s development and improvement go through the discovery of new electron sources of high brightness. After reminding the interests in studying silicon cathodes with array of tips as electron sources, I describe, in the three steps model, the main phenomenological features related to photoemission and photoemission and photo-field-emission from a semi-conductor. the experimental set-ups used for the measurements reported in chapter four, five and six are described in chapter three. In chapter three. In chapter four several aspects of photo-field-emission in continuous and nanosecond regimes, studied on the Clermont-Ferrand`s test bench are tackled. We have measured quantum efficacies of 0.4 percent in the red (1.96 eV). Temporal responses in the nanoseconds range (10 ns) were observed with the Nd: YLF laser. With the laser impinging at an oblique angle we obtained ratios of photocurrent to dark current of the order of twenty. The issue of the high energy extracted photocurrent saturation is addressed and I give a preliminary explanation. In collaboration with the L.A.L. (Laboratoire de l`Accelerateur Lineaire) some tests with shortened pulsed laser beam (Nd: YAG laser 35 ps) were performed. Satisfactory response times have been obtained within the limitation of the scope (400 ps). (authors). 101 refs. 93 figs., 27 tabs., 3 photos., 1 append.

  9. Report of the experts group on the taxation of the access to gas transport and distribution network; Rapport du groupe d'experts sur la tarification de l'acces aux reseaux de transport et de distribution de gaz

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-04-01

    In the framework of a new french gas industry organization (directive of the 22 june 1998), a concerting mission has been realized on prices taxation for the transport and distribution facilities. The following topics have been debated: the integration and competition of the european gas market, the gas market liberalization consistency and the taxation of transport and distribution network access. (A.L.B.)

  10. On tariffs of the transport and electricity distribution network. Stage report of the economic analysis group; Groupe d'expertise economique sur la tarification des reseaux de transport et de distribution de l'electricite. Rapport d'etape

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-08-17

    This report contains an Introduction, seven Sections, Conclusions and Summary of Recommendations, a Glossary and three Appendices. In the Introduction the work of the group is presented, the question of the access to the network is outlined and the approach adopted by the group is explained. The Section 1 is titled 'The electricity market and the questions raised by the access to network. The following issues are exposed: - Institutional and regulation context; - Transposition of the directive 96/92/CE within member states; - The effects of offer expected by France; - Expected effects for electricity consumers; - Abroad experience in organizing the access; - The role of the Electricity Regulation Commission and the objectives of tariffing and rules of access to transport network. The second section presents the characteristics of the Management of Distribution Network (GRT) and identification of the costs. The following items are treated: - Definition and description of the transport network; - Network development; - European interconnections; - Technical constraint; - Organization of GRT; - Calculation of transport; - Remuneration of capital; - Distribution, the transport's end-of-the-road; - Costs to recover: definition, problems of measurement and verification; - Transitory tariffs. The third section is titled 'Introduction to an economic approach' and it presents the nodal tariffing and an outlook of practical solutions. The forth section tackles with the main options in tariffing. Six issues are exposed: - The main choices to do; - Choosing between postal stamp and distant tariffing; - Sharing between producer and consumers; - Economic relevance of the postal stamp type formulas; - Sharing between energy and power; - A proposal of tariff structure. The Section 5 is devoted to tariffs for international transports. The following issues are exposed: - Specific questions posed by transfrontier contracts; - European Union frame; - Connection with the tariffs of domestic contracts; - Proposals for tariffing the international transports. The sixth section presents the efficiency of the short and medium term access. The following issues are tackled: - Regulation of access and transmission; - Short term treating of the bottlenecks; - De-congestion investments; - Tariffs for lead-in and reinforcement operations; - the case of proximity production, direct lines and self-production. Finally, the last section titled 'Inciting the GRT internal efficiency and tariffing evolution, displays the subject matters: - The GRT behaviour guide; - Evolution of tariffing; - Benchmarking possibilities. In the concluding section the basic ideas of the report i.e., improving the market functioning, developing the network management and inciting the grow in the internal efficiency of GRT are elaborated and entailing recommendations are set down.

  11. Concept for urban heating systems using co-generation; Conception de systemes de chauffage urbain pour la cogeneration. Phase I: application au quartier des Morasses (Martigny) de la methode de conception des reseaux de chauffage urbain developpe au LENI. Rapport final

    Energy Technology Data Exchange (ETDEWEB)

    Cherix, G. [Centre de competence en urbistique CREM, Martigny (Switzerland); Weber, C. [Swiss Federal Institute of Technology (EPFL), Laboratoire d' energetique industrielle (LENI), Lausanne (Switzerland)

    2006-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) reviews the work done in the first phase of a project concerning the concept for a district heating system in Martigny, Switzerland. This work was carried out by the Centre for Municipal and Energy Research CREM in Martigny, Switzerland, and the Laboratory for Industrial Energy LENI at the Swiss Federal Institute of Technology in Lausanne. Software developed at the LENI is introduced and its use for the determination of the necessary configuration and modes of operation of a district heating system in Martigny is discussed. The situation in the Morasses district of Martigny and the promising results obtained are looked at. These can lead to the optimisation of heating supply in other such areas.

  12. Cold distribution networks. Cold distribution by two-phase refrigerant fluid. Case of ice slurries; Reseaux de distribution de froid. Distribution de froid par fluide frigoporteur diphasique. Cas du coulis de glace stabilisee (2002 - 2004). Rapport final (1er juillet 2004). Programme energie. PRI 9.1

    Energy Technology Data Exchange (ETDEWEB)

    Lallemand, A. [Institut National des Sciences Appliquees (INSA), Centre de Thermique de Lyon (CETHIL), UMR 5008, 69 - Villeurbanne (France); Mercier, P. [CEA Grenoble, Groupement pour la Recherche sur les Echangeurs Thermiques (GRETH), 38 (France); Royon, L. [Paris-1 Univ., Lab. de Biorheologie et d' Hydrodynamique Physico-Chimique, 75 (France); Dumas, J.P. [L' Ecole Nationale Superieure en Genie des Technologies Industrielles, Lab. de Thermique Energetique et Procedes, 64 - Pau (France); Guilpart, J. [URGPAN/CEMAGRE, 33 - Bordeaux (France)

    2004-07-01

    This PRI aims to participate to the development of alternate solutions for refrigerant fluids, for the cold transport and more specially a two phase refrigerant fluid: the stabilized ice slurry. The research program presented three main axis: design, realization and characterization of stabilized ice slurry, experimental studies of transport and transfer properties, study of online measurement process of the solid content. A simulation has been realized to evaluate the energy efficiency of this refrigerant use. (A.L.B.)

  13. Contribution to the asymptotic estimation of the global error of single step numerical integration methods. Application to the simulation of electric power networks; Contribution a l'estimation asymptotique de l'erreur globale des methodes d'integration numerique a un pas. Application a la simulation des reseaux electriques

    Energy Technology Data Exchange (ETDEWEB)

    Aid, R.

    1998-01-07

    This work comes from an industrial problem of validating numerical solutions of ordinary differential equations modeling power systems. This problem is solved using asymptotic estimators of the global error. Four techniques are studied: Richardson estimator (RS), Zadunaisky's techniques (ZD), integration of the variational equation (EV), and Solving for the correction (SC). We give some precisions on the relative order of SC w.r.t. the order of the numerical method. A new variant of ZD is proposed that uses the Modified Equation. In the case of variable step-size, it is shown that under suitable restriction, on the hypothesis of the step-size selection, ZD and SC are still valid. Moreover, some Runge-Kutta methods are shown to need less hypothesis on the step-sizes to exhibit a valid order of convergence for ZD and SC. Numerical tests conclude this analysis. Industrial cases are given. Finally, an algorithm to avoid the a priori specification of the integration path for complex time differential equations is proposed. (author)

  14. The redefinition of the american and british gas industries: the regulation of the access load to the gas pipelines networks; La restructuration des industries gazieres americaine et britannique: la reglementation de la charge d'acces aux reseaux de gazoducs

    Energy Technology Data Exchange (ETDEWEB)

    David, L

    2000-10-01

    The transport and distribution networks regulation is the main stakes of the regulation reform of the gas industries. This thesis analyzes the models applied in The Usa and in the United Kingdom. The first part deals with the gas industries deregulation in these two countries, the impacts on the economy and the organization of the gas industries. The second part presents a theoretical approach of the regulation applied to the prices of the natural ags transport by gas pipelines. Regulation by the service cost price and by price cap are compared. (A.L.B.)

  15. Assessment of the radiological status of the French environment in 2008: synthesis of the results of the IRSN's watch networks; Bilan de l'etat radiologique de l'environnement francais en 2008. Synthese des resultats des reseaux de surveillance de l'IRSN

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This report presents the data obtained in 2008 within the frame of the follow-up by the IRSN of the levels of radioactivity on the French national territory. After having recalled the objectives of this radiological watch of the environment and its organization, the report describes the methodology adopted for the choice of the watch stations, the choice of the environmental matrices, the analysis plans, the sample preparation and packing. It presents the various radionuclides which are naturally or artificially present in the French environment. Then, it presents the results obtained by the different station networks by watching the atmosphere, rivers and soils, or coasts. The report recalls and comments the different radiological events which occurred in 2008, i.e. the detection of different radionuclides in different environments: nuclear plants, nuclear research centres, nuclear sites, nuclear industries, nuclear waste storage sites, nuclear marine bases, rivers.

  16. Distributed intelligent systems for substation automation - New methodology to manage the distribution networks in the presence of decentralized generation; Intelligence decentralisee appliquee a l'automatisation de sous-stations. Nouvelle methodologie pour gerer les reseaux de distribution en presence de production decentralisee

    Energy Technology Data Exchange (ETDEWEB)

    Yuen, Ch. [ABB Switzerland Ltd., Baden-Daettwil (Switzerland)

    2010-07-01

    This article describes a new concept for electric network management, developed by ABB Ltd. in co-operation with seven universities and two electric network utilities. This is a British project the aim of which is the distributed management of regional sub-networks by means of distributed control and intelligence. These network parts include intelligent devices, demand management, storage units and sub-stations and are widely autonomous. Such a new concept is required in particular due to increasing share of renewable energy sources in power generation. Moreover, most of these new generators deliver power in a stochastic way. The article explains the basic principles of the concept and describes the status of the project.

  17. Energy harvesting as power supply for personal wireless networks - Enhanced autonomy, lower cost, ecological advantage; Recolte d'energie pour alimentation des reseaux personnels sans fil. Plus d'autonomie, plus d'economies, plus d'ecologie

    Energy Technology Data Exchange (ETDEWEB)

    Meli, M.

    2009-07-01

    This comprehensive article gives an overview of the current status of energy harvesting technology development for applications in personal wireless networks. Energy harvesting is a generic term designating energy conversion from the surrounding of an electronic device in order to generate the power it needs for its operation. The energy source can be a mechanical vibration (piezo-electric generators), a temperature difference (Peltier elements), radiofrequency electromagnetic radiation, a magnetic field (Faraday induction law), light (photovoltaic cells), etc. Depending on the energy source, converters are needed to increase or decrease the output voltage. Storage elements like condensers or batteries may be necessary as well. Energy harvesting devices are particularly useful in wireless networks when power supply batteries of sensors or detectors cannot be replaced easily or only at high cost. The article describes the criteria to be considered in the selection of the adequate energy harvesting technology. The data transmission protocol to be used is also of great importance, as the quantity of data to be transmitted is. Both have a considerable impact on the energy consumption of the device to be supplied by energy harvesting. Finally, examples of applications currently in development at the Institute of Embedded Systems at the Zurich University of Applied Sciences in Winterthur, Switzerland are reported on.

  18. Evaluation of the radiological situation of the French environment in 2007. Synthesis of the I.R.S.N. surveillance networks; Bilan de l'etat radiologique de l'environnement francais en 2007. Synthese des resultats des reseaux de surveillance de l'IRSN

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    After a reminder of the objectives and the organisation of the radiological surveillance, the radiological events detected in 2007 are given: high tritium activity in a water sampling (Saclay), detection of alpha emitters in aerosols sampling (Pierrelatte), detection of cobalt 60 in an aerosol sampling (Somanu Areva), increase of a global beta activity in aerosols (north-east and center of France), detection of uranium in water (Pithiviers). We find then the results of the surveillance of fuel cycle sites, the results of the surveillance of the research centers and naval base, the results of the surveillance of radioactive release of nuclear medicine services, the results of the general surveillance of the territory (and the different Internet sites that give these data). This report ends with notions about radioactivity and ionizing radiations as well as radiation protection basic knowledge. (N.C.)

  19. Towards the prediction of the growth of crack networks: influence of microstructural parameters on scattering at initiation; Vers la prediction de l'apparition de reseaux de fissures: influence des parametres microtructuraux sur la dispersion a l'amorcage

    Energy Technology Data Exchange (ETDEWEB)

    Osterstock, St

    2008-10-15

    This research thesis aims at understanding the importance of microstructure in the scattering of mechanical fields and of its potential influence on fatigue crack initiation, at studying the grains in which equi-biaxial fatigue cracks are appearing, and at proposing a coalescence model based on the discrete dislocation dynamics (DDD). After an overview of fatigue, the author describes the tests developed by EDF or the CEA to study thermal fatigue. Then, he presents the equi-biaxial fatigue test which allows the first stages of initiation of thermal fatigue cracks to be studied. Maps of cracked areas are obtained by Electron Back Scattered Diffraction, and results are discussed with respect to results obtained in dislocation dynamics. Polycrystalline computations are implemented. They allow a better understanding of the importance of the material microstructure for the scattering of the surface grain mechanical fields. Finally, a coalescence model is presented, based on experimental results obtained during the equi-biaxial fatigue testing. Coalescence criteria are proposed.

  20. Information report on electricity distribution network security and financing; Rapport d'information depose en application de l'article 145 du reglement par la Commission des Affaires Economiques sur la securite et le financement des reseaux de distribution d'electricite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This report first outlines the degradation of electricity quality, and identifies the lack of investment as the main reason of the network weakness. It notices that the French network is much extended, and that the medium and low voltage networks need to be secured, and outlines that some legal measures have already been implemented to correct these problems. In its second part, the report comments the network manager's point of view, and denies his critics of the conceding authorities. It also discusses the network manager's investments, and finally formulates six propositions for a better future of the distribution network

  1. Medgrid: a major industrial initiative for Mediterranean power grids - Opening new electricity paths for a sustainable energy development of the Union for the Mediterranean area countries; Medgrid: Une initiative industrielle majeure pour les reseaux electriques mediterraneens - Ouvrir de nouvelles voies a l'electricite pour un developpement energetique durable des pays de l'Union pour la Mediterranee

    Energy Technology Data Exchange (ETDEWEB)

    Merlin, Andre [MEDGRID, 38, avenue Hoche, 75008 Paris (France); Reseau de Transport d' Electricite - RTE, Conseil De Surveillance, 1 terrasse Bellini, TSA 41000, 92919 La Defense Cedex (France); Electricite Reseau Distribution France - ERDF, Conseil De Surveillance, Tour Winterthur, 102 terrasse Boieldieu, 92085 Paris La Defense (France); CIGRE, 21, Rue D' Artois 75008 Paris (France); Pouliquen, Herve [MEDGRID, 38, avenue Hoche, 75008 Paris (France)

    2011-07-01

    The development of new electricity networks in the Mediterranean region has given rise to a lot of new hope. Electricity is truly at the heart of economic and social development, but also represents an appropriate solution for improving the energy efficiency of many end use applications and for increasing the environmental protection where it is produced from renewable forms of energy. Launched under the framework of Union for the Mediterranean, a key project of the Mediterranean Solar Plan, Medgrid was set up at the instigation of the French government; it now gathers twenty industrial shareholders from different economic sectors: power generation, transmission, distribution and supply, financing and the sustainable development service industry, who are joining together to study the feasibility of a large transmission grid between the south and north rims of the Mediterranean Sea. Medgrid forms part of a new dynamic - set in motion over ten years ago - in Euro-Mediterranean relations, in environmental initiatives and in energy infrastructure development policies. It is important to be reminded of the main features of these initiatives and of their results in order to fully understand the huge diversity of the context in which Medgrid is going to operate, be it in the political, institutional, economic, industrial and technological spheres. (authors)

  2. Radiological assessment of the French environment in 2008. Synthesis of the IRSN's surveillance networks; Bilan de l'etat radiologique de l'environnement francais en 2008. Synthese des resultats des reseaux de surveillance de l'IRSN

    Energy Technology Data Exchange (ETDEWEB)

    Chaptal-Gradoz, N.; Chevreuil, M.; D' amico, D.; Debayle, Ch.; Leprieur, F.; Manificat, G.; Peres, J.M.; Pierrard, O.; Tournieux, D.; Veran-Viguie, M.P.; Renaud, Ph.; Roussel-Debet, S.; Masson, O.; Pourcelot, L.; Fayolle, C.; Loyen, J.; Robe, M.Ch.; Picolo, J.L.; Gallerand, M.O

    2009-07-01

    While providing many maps, graphs and tables, this report presents and comments the very large amount of data acquired in 2008 within the frame of the control by the IRSN of radioactivity levels on the French national territory by means of its different surveillance networks. After a presentation of these networks (objectives, organization, sample collection, analysis, and preparation methodologies) and of the different radionuclides present in the French environment, results are presented by installation type (electricity production nuclear centres, nuclear fuel reprocessing centres, nuclear medicine centres, nuclear waste storage centres, research centres, nuclear naval bases, etc.) and environment component (air, water ways, rain waters, continental or coastal environment, biological media, etc.)

  3. Report related to the mitigation of the impact of major climate events on the operation of electricity distribution networks; Rapport relatif a la limitation de l'impact des evenements climatiques majeurs sur le fonctionnement des reseaux de distribution d'electricite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    After a presentation of the main characteristics of the French electricity distribution network, this report discusses the lessons learnt from recent tempests which occurred in 1999, 2008, 2009 and 2010. It identifies measures and technologies to be implemented to improve the network security. Then, it shows that the present institutional context does not lend itself to an optimisation of investment choices in terms of security. The last part discusses the security plan sizing which needs a better assessment of tempest-related risks

  4. Smart grids, demand-side management and decentralised electricity production: Mounting a national R and D programme; Reseaux intelligents, maitrise de la demande et production decentralisee d'electricite: Initiative de montage d'un programme national de R and D

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    This report summarises the results of a collective enquiry conducted between May and December 2007 and coordinated by TECHNOFI. This study had four goals: 1) analyse the role of actors in French research, in terms of new knowledge to be acquired regarding electricity networks, in order to optimise operations in the future and bring electricity generation, transmission and distribution to play their full role in policies designed to reduce greenhouse gas emissions, 2) propose a new conceptual framework for national R and D on electricity networks, complementing work currently pursued by researchers in France, in order to explore in greater detail other possible futures for electricity networks, 3) set up organisational and financial modes for this additional research, based on a list of projects that clearly distinguishes between European and national public funding, 4) link these proposed directions for research, organisation and funding to an industrial vision ensuring that national manufacturers and parts makers will continue to rank among the top global competitors. This analysis objectively demonstrates that France holds a unique position in the European landscape of power-grid research and development. France is one of the EU countries where operators, accompanied by public authorities, continue to invest heavily in the grid, compared to other countries with equivalent GDP (Germany, Italy, Spain, Great Britain). Annual R and D expenditures are on the order of euros 65 M, when those of RTE, ERDF (including EDF-R and D), the CNRS and ADEME are added up. Research subsidies from the CEC obtained competitively by French researchers add another {approx}5 M annually to the total. These R and D investments do not include the contribution of industrial groups such as AREVA, SCHNEIDER and NEXANS and other national equipment suppliers who operate world-wide, Europe being only a small part of their activity due to the economic growth of emerging countries. With this high level of investment RTE, ERDF and EDF-R and D dispose of teams that can identify future R and D needs, pilot and conduct research, and integrate the results, often obtained in collaboration with other parties, in innovative demonstration projects set up by operators. This is no longer the case for many of their European counterparts where research teams have shrunk to a minimum, following cost-cutting decisions and 'rationalisation' of grid activities (decisions made on the basis of short-term business policies, often encouraged by regulators 3). These encouraging observations notwithstanding, transmission and distribution grid operators in France consider that they must acquire further knowledge pertaining to the sizing and operation of electricity networks. Five policy options underlie this vision extending to 2020, a vision aimed at validating new directions for the evolution of these networks: 1 - Strengthen the capacity of the transmission grid to integrate an energy bouquet that complies with European commitments for de-carbonising electricity generation, via the development of renewable energy, 2 - Make the distribution grid flexible and reliable enough to meet the consumer demand and the requirements of energy service vendors, 3 - Coordinate interaction between transmission operators and distributors so as to reinforce the reliability of the grid in France, optimise its energy performance and contribute to building the single electricity market in Europe, 4 - Encourage electricity demand management as an additional source of supply and economic competitiveness, 5 - Expand decentralised generation, particularly to help further reduce energy demand in commercial and residential buildings

  5. Tariff proposal of the Commission of energy regulation from February 28, 2008 for the use of public natural gas distribution networks; Proposition tarifaire de la Commission de regulation de l'energie du 28 fevrier 2008 pour l'utilisation des reseaux publics de distribution de gaz naturel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    With the complete opening of natural gas markets to competition and the legal separation of distribution networks, Gaz de France Reseau Distribution requested the implementation of a new tariff of use of gas distribution networks to the Commission of energy regulation (CRE). A new tariff of networks utilisation has thus been proposed by CRE after a public consultation and the audition of gas suppliers. This tariff foresees a 5.6% increase of the present day tariff by July 1, 2008. The impact on the end-users' gas retail price will be a 1.5% rise of the regulated tariff. (J.S.)

  6. Translations on Telecommunications Policy, Research and Development, Number 19

    Science.gov (United States)

    1977-11-09

    TELECOMMUNICATIONS, Sep 77) 54 PTT’s Social Action Policy Detailed (MESSAGES DES POSTES ET TELECOMMUNICATIONS, Sep 77) 58 GREECE Briefs...undertaken that are counter to state and social requirements for order and security. (5) If amateur radio stations of the GST are operated for...telephone (1)-567-70-97. 52 Reseaux eommutea Dibit (bHt/i) Liaisons specialities telex telephone Caducee TRANSPAC 50 200 1200 2400

  7. Technical Programme 1993 (Le Programme Technique, 1993)

    Science.gov (United States)

    1992-09-01

    Specialistes sur "Les Reseaux Internationaux a Grande Vitesse pour les Programmes d’Information Scientifique et Technique" 11-15 USA GCP Panel Meeting/Symposium...automation - Objectives Expectation of air traffic grcwth (to meet) Increase use of available capacity Meeting future social mandate Need of machine...capacity... Decision supports - Future role of the man-in-the-control-loop . Social aspects - Onboard - on the ground - Current practice - critical

  8. 6TH Saint Petersburg International Conference on Integrated Navigation Systems.

    Science.gov (United States)

    1999-10-01

    originale de la technique des filtres federes a ete faite par analogie avec les reseaux electriques. Cette approche apporte un eclairage interessant sur la...will come out to the reader on the boundary of the XXI century as a direct result of the radical social reformation which has been under way in...Russia since perestroika began in the former Soviet Union and the socialist countries. The new social processes have destroyed nearly an age-long

  9. Multi-Sensor Systems and Data Fusion for Telecommunications, Remote Sensing and Radar (les Systemes multi-senseurs et le fusionnement des donnees pour les telecommunications, la teledetection et les radars)

    Science.gov (United States)

    1998-04-01

    polarization component in the confinement direction, i.e. normal incidence absorption is forbidden by the dipole selection rules.[3] Therefore, n...Photodetector and Light Emitting Diode", Electron. Lett. 31, 832 (1995). 3. L. C. West and S. J. Eglash, "First Observation of an Extremely Large- Dipole ...theorie des graphes. II a une importance vitale pour 1’elaboration des reseaux electriques , telephoniques. Dans le contexte des systemes multi-senseurs

  10. Une clinique de l'accueil et de l'accompagnement. La prise en charge d'une famille demandeur d'asile politique réfugiée en France

    OpenAIRE

    Mouchenik, Y.; Shehadeh, S.; Sicard, S.; Montclos, M.O. Pérouse De; Moro, M.R.

    2010-01-01

    Resume Les consequences psychologiques et psychiatriques des traumatismes vecus par les populations refugiees sont considerables et constituent un probleme de sante publique. A cela va s?ajouter dans le pays d?accueil, l?isolement, les pertes de contenants culturels, la remise en jeu du sentiment d?identite, la perte des reseaux familiaux et sociaux, les difficultes d?adaptations sociales, economiques, linguistiques, les discriminations et une longue et menacante incertitude quant ...

  11. Study of heterogeneous multiplying and non-multiplying media by the neutron pulsed source technique; Etude des milieux heterogenes multiplicateurs et non-multiplicateurs par la technique de la source pulsee de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Deniz, V. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-06-01

    The pulsed neutron technique consists essentially in sending in the medium to be studied a short neutron pulse and in determining the asymptotic decay constant of the generated population. The variation of the decay constant as a function of the size of the medium allows the medium characteristics to be defined. This technique has been largely developed these last years and has been applied as well to moderator as to multiplying media, in most cases homogeneous ones. We considered of interest of apply this technique to lattices, to see if useful informations could be collected for lattice calculations. We present here a general theoretical study of the problem, and results and interpretation of a series of experiments made on graphite lattices. There is a good agreement for non-multiplying media. In the case of multiplying media, it is shown that the age value used until now in graphite lattices calculations is over-estimated by about 10 per cent. [French] La technique de la pulsation neutronique consiste essentiellement a envoyer dans le milieu a etudier une courte bouffee de neutrons et a determiner la constante de decroissance asymptotique de la population engendree. La variation de cette constante de decroissance en fonction des dimensions du milieu permet de determiner ses caracteristiques. Cette technique a connu ces dernieres annees un grand essor et a ete appliquee a des moderateurs et des milieux multiplicateurs. Il s'agissait dans la plupart des cas de milieux homogenes. Il nous a semble interessant de l'utiliser dans le cas des reseaux, afin de voir si ces experiences peuvent fournir des renseignements utiles aux calculs. Nous presentons ici une etude theorique generale du probleme, ainsi que les resultats et l'interpretation d'une serie d'experiences faites sur des reseaux a graphite. L'accord est bon dans le cas des reseaux non-multiplicateurs. Dans le cas des reseaux multiplicateurs, on montre que la valeur de l

  12. Melange a Six Ondes Degenere dans les Absorbants Saturables

    Science.gov (United States)

    Blouin, Alain

    Issus d'une generalisation du melange a quatre ondes degenere, les melanges a n ondes degeneres sont utiles pour la mesure des divers ordres de la susceptibilite nonlineaire. Nous avons procede a l'etude theorique et experimentale du melange a six ondes degenere dans des absorbants isotropes et anisotropes. Pour l'analyse theorique, nous avons developpe une methode de calcul basee sur une approche holographique. Cette methode fut utilisee pour l'etude du melange a six ondes en regimes stationnaire et transitoire sous des conditions de faibles et de fortes saturations. Des experiences realisees a l'aide d'impulsions excitatrices de courte duree, soit 33 picosecondes, dans des verres dopes aux semi-conducteurs et dans la Rhodamine 6G en solution ont permis de verifier la validite de notre modele theorique. Nous avons aussi etudie les oscillateurs auto-pompes par melange a six ondes degenere.

  13. Cinétique de photodéposition aux temps longs et réalisation de réseaux permanents modulables

    Science.gov (United States)

    Hugonnot, E.; Delville, J. P.

    2002-06-01

    La cinétique de photodéposition aux temps longs est étudiée expérimentalement dans une solution à base de chromate et théoriquement en utilisant un modèle thermodynamique de croissance de goutte. Un comportement universel de la croissance aux temps longs est alors trouvé. L'application de la photodéposition à la réalisation de réseaux holographiques est montrée et l'ajustement du modèle à partir de la figure de diffraction expérimentale permet de remonter à l'évolution temporelle de la morphologie induite par le champ laser.

  14. La Vie Politique sous la Restauration a Travers ’Le Rouge et le Noir’ de Stendahl (The Political Life during the Restauration as Depicted in Le Rouge et le Noir by Stendahl)

    Science.gov (United States)

    1989-01-01

    reSeauX du pouvoir est celul des societes secretes. Le vicaire se trouve A la tete de la congregation bisontine. la congregation etant le nom general pour...I’odieux sur l’autorite& legItime. Pauvre France !" (p.138) Pour conserver leur distinction sociale , les nobles utilisent des signes de stature. M. de la...une depense necessaire pour soutenir notre rang." (p.13) Pourtant, ce recours reussit! M. de Renal retablit ainsi sa sup~riorit6 sociale pr~tendue

  15. Adaptation des Temps de Retournement et Silence des Agents (MICROFIP) sur ceux du MANAGER (FULLFIP)

    CERN Document Server

    Brun, R

    2005-01-01

    Suite a des defauts de lecture entre le module FIPDIAG (MICROFIP) et le MANAGER (FULLFIP) lors de la qualification des reseaux du LHC, l'equipe du WorldFIP Support, avec l'aide d'Alstom, s'est rendu compte que le Temps de Retournement (Tr) des Agents MICROFIP ne devait pas etre minimal mais ajuste sur le mode operationnel du MANAGER (FULLFIP) qui est variable suivant la configuration du BA. Pour le Temps de silence (Ts) les precautions a prendre sont les memes.

  16. Controle optique de qubits lies a des centres isoelectroniques d'azote dans le GaAs

    Science.gov (United States)

    Ethier-Majcher, Gabriel

    Le traitement de l'information quantique est un domaine de recherche actuellement en pleine effervescence car il laisse entrevoir une revolution dans notre facon de traiter et d'echanger de l'information. D'une part, l'ordinateur quantique promet de resoudre des problemes comme la factorisation d'un polynome de facon beaucoup plus efficace qu'un ordinateur classique. D'autre part, les communications quantiques promettent l'echange d'information de facon fondamentalement inviolable. Afin de tirer pleinement profit de ces nouvelles technologies, il sera avantageux de construire des reseaux quantiques. Dans un tel reseau, des processeurs quantiques, les noeuds, seront connectes par des photons voyageant dans des fibres optiques. Les reseaux quantiques permettront de deployer les communications quantiques a grande echelle et de creer des super-ordinateurs quantiques. La realisation de reseaux quantiques necessitera des interfaces optiques pouvant echanger l'information de facon coherente entre un qubit (bit d'information quantique) et un photon. L'implementation de telles interfaces dans un systeme physique s'avere un important defi scientifique et technologique. Or, les systemes actuellement envisages a cette fin souffrent d'un faible couplage avec la lumiere ou encore de grandes inhomogeneites, constituant des obstacles a la realisation de reseaux a grande echelle. Dans cette these, le potentiel des centres isoelectroniques pour realiser des interfaces optiques est evalue. Deux types de qubits lies a des paires d'azote dans le GaAs sont consideres : les qubits excitoniques et les qubits de spin electronique, controlables par l'intermediaire d'excitons charges. Le controle optique complet des qubits excitoniques est demontre, ce qui constitue la premiere realisation du genre dans les centres isoelectroniques. L'observation d'excitons charges dans ce systeme, liant a la fois des trous lourds et des trous legers, laisse entrevoir de nouvelles possibilites afin de

  17. Technology, environmental protection and economic efficiency. Cables at the Cigre 2010 in Paris; Technik, Umwelt und Wirtschaftlichkeit. Kabeltechnik auf der Cigre 2010 in Paris

    Energy Technology Data Exchange (ETDEWEB)

    Wiznerowicz, Fred [Fachhochschule Hannover (Germany)

    2010-12-13

    Cigre (Conseil International des Grands Reseaux Electriques), founded in 1921, today has about 6,000 members in 90 countries. Their work is reflected in international standards. In consequence, the work of the Cigre is very important for the electric power industry and the public utilities. The 43th Cigre was held in Paris in late August 2010, with an attendance of more than 3,000. The German delegation consisted of more than 220 experts. The conference provided an opportunity to exchange knowledge between the various sectors of power transmission, e.g. cables, overhead transmission lines, switching stations, and environmental aspects. (orig.)

  18. Extracting spatial information from large aperture exposures of diffuse sources

    Science.gov (United States)

    Clarke, J. T.; Moos, H. W.

    1981-01-01

    The spatial properties of large aperture exposures of diffuse emission can be used both to investigate spatial variations in the emission and to filter out camera noise in exposures of weak emission sources. Spatial imaging can be accomplished both parallel and perpendicular to dispersion with a resolution of 5-6 arc sec, and a narrow median filter running perpendicular to dispersion across a diffuse image selectively filters out point source features, such as reseaux marks and fast particle hits. Spatial information derived from observations of solar system objects is presented.

  19. Photosensibilite et ecriture de guides d'ondes dans les couches minces de verre de chalcogenures

    Science.gov (United States)

    Ho, Nicolas

    Les travaux presentes portent sur le developpement de dispositifs plans a base de verre de chalcogenures. Les verres de la famille As-S-Se sont utilises, et en particulier l'As2S 3. Les verres de chalcogenures sont des semiconducteurs amorphes qui sont tres interessants du point de vue de l'optique dans le proche infrarouge. La formation de guides auto-inscrits dans des couches minces d'As2S3 est etudiee experimentalement et numeriquement. La grande photosensibilite de ce verre mene a de nouveaux comportements de formation qui sont demontres. L'auto-inscription est aussi utilisee pour caracteriser la photosensibilite des couches minces de verre de chalcogenures dans le proche infrarouge, ce qui est un probleme majeur pour le developpement de dispositifs d'optique non lineaire a base de ces materiaux. Differentes caracteristiques de cette photosensibilite sont mises en evidences, comme la presence d'un seuil en intensite, entre autres. Finalement, une application des verres de chalcogenures est presentee: la fabrication de matrices de guides d'ondes (waveguide arrays) a l'aide d'une technique holographique novatrice.

  20. Melange a Quatre Ondes Degenere dans les Absorbants Saturables EN Milieu Mince

    Science.gov (United States)

    O'Neill, Claire

    1995-01-01

    Le melange a quatre ondes est utilise notamment pour determiner la duree des temps de reorientation moleculaire et mesurer la grandeur des susceptibilites nonlineaires du troisieme ordre. Nous avons mis en evidence les particularites du melange a quatre ondes degenere en milieu absorbant mince a l'aide du formalisme de l'optique nonlineaire et de l'approche holographique. Des experiences realisees avec des impulsions de 33 ps ont permis de caracteriser la cinetique de la nonlinearite en regime transitoire des molecules de rhodamine 6G incorporees dans des matrices d'alcool polyvinylique; un milieu aussi compose d'absorbants anisotropes, les molecules de rhodamine 6G en solution aqueuse et un autre forme d'absorbants isotropes, les films minces de cristaux de semiconducteur CdS_ {x}Se_{1-x} ont ete etudies. Nous avons observe pour ces trois milieux les signaux generes aux ordres superieurs par melange a quatre ondes degenere en milieu mince pour differentes conditions de polarisation.

  1. Compréhension des processus magmatiques et localisation de source sismo-volcanique avec des antennes sismiques multicomposantes

    OpenAIRE

    INZA CALLUPE, Lamberto Adolfo

    2013-01-01

    Dans cette thèse, nous étudions le problème de la localisation de sources sismo-volcanique, à partir des données enregistrées par des r'{e}seaux de capteurs composés de nouveaux sismomètres à trois composantes (3C). Nous nous concentrerons sur le volcan Ubinas, l'un des plus actifs au Pérou. Nous développons une nouvelle approche (MUSIC-3C) basée sur la méthode MUSIC permettant de retourner les 3 paramètres utiles (lenteur, azimut et incidence). Pour valider notre méthodologie, nous analysons...

  2. Effects of temperature fluctuations of IUE data quality

    Science.gov (United States)

    Thompson, R. W.; Turnrose, B. E.; Bohlin, R. C.

    1981-01-01

    Analysis of IUE calibration lamp images shows that variation in the temperature of the scientific instrument causes shifts in the location of the spectral format with respect to the reseau grid on the detector and in the location of the reseaux themselves. In high dispersion, a camera head amplifier temperature difference of 6C corresponds to a shift of 4 pixels in the spectral format for LWR and 2 pixels for SWP along the dispersion direction. Shifts perpendicular to the disperson (for the same temperature difference) are less than one pixel for both cameras. In low dispersion spectra, the shifts are similar but orthogonal to those described above with the larger motion lying in the direction perpendicular to the dispersion. In both dispersion modes, the observed shifts are apparently independent of wavelength. In high dispersion, the constant pixel shift mimics a constant velocity error.

  3. Proceedings of the 2010 CIGRE Canada conference on power systems : power system solutions for a cleaner, greener world

    Energy Technology Data Exchange (ETDEWEB)

    Pataky, J.; Zucker, R.; Ramsay, H.; La Rose, J.; Garbe, S. [BC Hydro, Burnaby, BC (Canada)] (comps.)

    2010-07-01

    The Conseil International des Grands Reseaux Electriques (CIGRE) is the International Council on Large Electric Systems which promotes technical, economic and environmental developments in electricity transmission and generation. CIGRE Canada, the Canadian National Committee, hosted this fifth annual conference on power systems to advance power system solutions and the capabilities of power systems. The participants from Canada, United States, Germany, Sweden, China, India, Thailand, Iran and Sudan included practicing engineers, managers, professors, university students and other professionals. The sessions at this conference were entitled: smart grids; asset management; modeling and methods; IT communication and data; system planning and reliability; new technologies; control and protection; and challenging issues. CIGRE study committee representatives presented their committees' annual reports and keynote speakers discussed important issues in the electric power industry during plenary sessions. All 54 presentations from this conference have been catalogued separately for inclusion in this database. refs., tabs., figs.

  4. Restoration of HST images with missing data

    Science.gov (United States)

    Adorf, Hans-Martin

    1992-01-01

    Missing data are a fairly common problem when restoring Hubble Space Telescope observations of extended sources. On Wide Field and Planetary Camera images cosmic ray hits and CCD hot spots are the prevalent causes of data losses, whereas on Faint Object Camera images data are lossed due to reseaux marks, blemishes, areas of saturation and the omnipresent frame edges. This contribution discusses a technique for 'filling in' missing data by statistical inference using information from the surrounding pixels. The major gain consists in minimizing adverse spill-over effects to the restoration in areas neighboring those where data are missing. When the mask delineating the support of 'missing data' is made dynamic, cosmic ray hits, etc. can be detected on the fly during restoration.

  5. A Kepler study of starspot lifetimes with respect to light-curve amplitude and spectral type

    Science.gov (United States)

    Giles, Helen A. C.; Collier Cameron, Andrew; Haywood, Raphaëlle D.

    2017-12-01

    Wide-field high-precision photometric surveys such as Kepler have produced reams of data suitable for investigating stellar magnetic activity of cooler stars. Starspot activity produces quasi-sinusoidal light curves whose phase and amplitude vary as active regions grow and decay over time. Here we investigate, first, whether there is a correlation between the size of starspots - assumed to be related to the amplitude of the sinusoid - and their decay time-scale and, secondly, whether any such correlation depends on the stellar effective temperature. To determine this, we computed the auto-correlation functions of the light curves of samples of stars from Kepler and fitted them with apodised periodic functions. The light-curve amplitudes, representing spot size, were measured from the root-mean-squared scatter of the normalized light curves. We used a Monte Carlo Markov Chain to measure the periods and decay time-scales of the light curves. The results show a correlation between the decay time of starspots and their inferred size. The decay time also depends strongly on the temperature of the star. Cooler stars have spots that last much longer, in particular for stars with longer rotational periods. This is consistent with current theories of diffusive mechanisms causing starspot decay. We also find that the Sun is not unusually quiet for its spectral type - stars with solar-type rotation periods and temperatures tend to have (comparatively) smaller starspots than stars with mid-G or later spectral types.

  6. Fine tuning of optical signals in nanoporous anodic alumina photonic crystals by apodized sinusoidal pulse anodisation.

    Science.gov (United States)

    Santos, Abel; Law, Cheryl Suwen; Chin Lei, Dominique Wong; Pereira, Taj; Losic, Dusan

    2016-11-03

    In this study, we present an advanced nanofabrication approach to produce gradient-index photonic crystal structures based on nanoporous anodic alumina. An apodization strategy is for the first time applied to a sinusoidal pulse anodisation process in order to engineer the photonic stop band of nanoporous anodic alumina (NAA) in depth. Four apodization functions are explored, including linear positive, linear negative, logarithmic positive and logarithmic negative, with the aim of finely tuning the characteristic photonic stop band of these photonic crystal structures. We systematically analyse the effect of the amplitude difference (from 0.105 to 0.840 mA cm -2 ), the pore widening time (from 0 to 6 min), the anodisation period (from 650 to 950 s) and the anodisation time (from 15 to 30 h) on the quality and the position of the characteristic photonic stop band and the interferometric colour of these photonic crystal structures using the aforementioned apodization functions. Our results reveal that a logarithmic negative apodisation function is the most optimal approach to obtain unprecedented well-resolved and narrow photonic stop bands across the UV-visible-NIR spectrum of NAA-based gradient-index photonic crystals. Our study establishes a fully comprehensive rationale towards the development of unique NAA-based photonic crystal structures with finely engineered optical properties for advanced photonic devices such as ultra-sensitive optical sensors, selective optical filters and all-optical platforms for quantum computing.

  7. Notice of the Electric Power Control Commission at the 1 february 2001 on the decree concerning the information confidentiality held by the public networks of transportation or electric power distribution, taking into account for the application of the 16 and 20 sections of the law number 2000-108 of the 20 february 2000 related to the modernization and the development of the electrical utilities; Avis de la Commission de regulation de l'electricite en date du 1 fevrier 2001 sur le decret relatif a la confidentialite des informations detenues par les gestionnaires de reseaux publics de transport ou de distribution d'electricite pris pour l'application des articles 16 et 20 de la loi no 2000-108 du 20 fevrier 2000 relative a la modernisation et au developpement du service public de l'electricite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This document presents the decree concerning the information confidentiality held by the public networks of transportation or electric power distribution, taking into account for the application of the 16 and 20 sections of the law number 2000-108 of the 20 february 2000 related to the modernization and the development of the electrical utilities and a comment of this decree by J. Syrota. (A.L.B.)

  8. Kinetics of heterogeneous systems; La cinetique des milieux heterogenes

    Energy Technology Data Exchange (ETDEWEB)

    Deniz, V. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    In this report, a general transport theory treatment is presented for the kinetics study as applied to finite heterogeneous systems. The theory is applicable to experiments near the critical point as well as to pulsed neutron experiments on multiplying or non-multiplying lattices. The general method is also applied to exponential experiments on infinite non-diverging lattices. The particularity of the present study is the explicit introduction of heterogeneity in the formulation and the search for the dependence of the parameters on the buckling of the finite medium. As a result of this, the finite medium parameters are in the first place expressed in terms of the corresponding infinite medium ones through the buckling and the anisotropic migration areas, and in the second place all the parameters are expressed as integrals only over an unit cell instead of over the whole pile. A preliminary less detailed study is first made in order to distinguish clearly between what are called 'dynamic parameters' and 'static parameters', and to define the meanings given in this report to these two terms. In the appendices are given approximate one-group treatments for the study of the dynamic fine structure, the time constant in infinite lattices, and the anisotropic diffusion coefficients in non-multiplying lattices. (author) [French] On presente dans ce rapport une methode generale, utilisant la theorie du transport pour l'etude de la cinetique des milieux finis heterogenes. La theorie est applicable aussi bien aux experiences pres de la criticite qu'aux experiences par sources pulsees de neutrons sur des reseaux multiplicateurs ou non-multiplicateurs. La methode generale est aussi appliquee aux experiences exponentielles sur des reseaux infinis non-divergents. La particularite de l'etude est l'introduction explicite de l'heterogeneite dans la formulation et la recherche de la dependance des parametres par rapport au laplacien du

  9. Prediction du profil de durete de l'acier AISI 4340 traite thermiquement au laser

    Science.gov (United States)

    Maamri, Ilyes

    Les traitements thermiques de surfaces sont des procedes qui visent a conferer au coeur et a la surface des pieces mecaniques des proprietes differentes. Ils permettent d'ameliorer la resistance a l'usure et a la fatigue en durcissant les zones critiques superficielles par des apports thermiques courts et localises. Parmi les procedes qui se distinguent par leur capacite en terme de puissance surfacique, le traitement thermique de surface au laser offre des cycles thermiques rapides, localises et precis tout en limitant les risques de deformations indesirables. Les proprietes mecaniques de la zone durcie obtenue par ce procede dependent des proprietes physicochimiques du materiau a traiter et de plusieurs parametres du procede. Pour etre en mesure d'exploiter adequatement les ressources qu'offre ce procede, il est necessaire de developper des strategies permettant de controler et regler les parametres de maniere a produire avec precision les caracteristiques desirees pour la surface durcie sans recourir au classique long et couteux processus essai-erreur. L'objectif du projet consiste donc a developper des modeles pour predire le profil de durete dans le cas de traitement thermique de pieces en acier AISI 4340. Pour comprendre le comportement du procede et evaluer les effets des differents parametres sur la qualite du traitement, une etude de sensibilite a ete menee en se basant sur une planification experimentale structuree combinee a des techniques d'analyse statistiques eprouvees. Les resultats de cette etude ont permis l'identification des variables les plus pertinentes a exploiter pour la modelisation. Suite a cette analyse et dans le but d'elaborer un premier modele, deux techniques de modelisation ont ete considerees, soient la regression multiple et les reseaux de neurones. Les deux techniques ont conduit a des modeles de qualite acceptable avec une precision d'environ 90%. Pour ameliorer les performances des modeles a base de reseaux de neurones, deux

  10. L Modele de Hubbard a Faible Densite et a Proximite du Demi-Remplissage quelques Aspects

    Science.gov (United States)

    Dare, Anne-Marie

    Ce travail, qui concerne quelques aspects du modele de Hubbard, se divise en deux volets. Dans une premiere partie, nous etudions une approximation simple basee sur l'idee de renormalisation de l'interaction par les effets a courte portee. Elle se justifie a basse densite et possede la propriete de satisfaire les relations de croisement fermioniques. Des comparaisons detaillees aux resultats de simulations Monte Carlo pour les fonctions de correlation de spin, de charge et de paire de diverses symetries, nous permettent d'identifier les effets essentiels dans ce regime d'interaction moderee, et de preciser les regions ou les effets non triviaux se manifestent. Cette approximation est egalement reliee a la theorie des liquides de Fermi, et nous permet d'interpreter les resultats a faible remplissage de bande, et sur petits reseaux, d'un point de vue liquide de Fermi faiblement correle. Dans une deuxieme partie, nous nous placerons a proximite du demi-remplissage de bande, pour uel une approche recemment developpee est particulierement adequate: elle predit conformement au theoreme de Mermin-Wagner, l'absence de transition magnetique a temperature finie en 2D. Cette theorie satisfait quelques exigences des relations de croisement. Nous nous interesserons a l'apparition et a la caracterisation d'une transition de phase antiferromagnetique par l'inclusion d'un faible effet tridimensionnel. Quelques comparaisons aux resultats experimentaux sur le compose de La_2CuO_4 sont discutees.

  11. Proceedings of the 2009 CIGRE Canada conference on power systems : innovation and renewal : building the new power system

    International Nuclear Information System (INIS)

    2009-01-01

    The Conseil International des Grands Reseaux Electriques (CIGRE) is the International Council on Large Electric Systems. It promotes technical, economic and environmental developments in electricity transmission and generation. CIGRE Canada is the Canadian National Committee which fosters the participation of Canadian members in CIGRE activities. CIGRE Canada organizes an annual conference that provides a forum for power system engineers, decision makers,economists, and academics to discuss technological developments in electrical power systems. The presentations at this conference addressed issues regarding the use of renewable energy sources in power transmission and distribution systems, with particular reference to control and protection; HVDC and MVDC; modelling tools; interface technologies; and reduced carbon generation and sustainability. The use of active distribution systems was also discussed in terms of future trends; the role of information technology and communications; and the role of energy storage. The session on smart grids addressed issues such as power utility perspectives; sensing, measurements and controls; advanced interfaces and decision support systems; open-architecture; distributed energy resources; and regulatory issues. Issues concerning the interconnection of non traditional energy sources to the power systems were also discussed along with recent research initiatives related to renewable energy source development. The sessions were entitled: smart grids; distributed energy resources; wind and solar PV; AC systems and HV lines; wide area measurements; power system operation and control; modelling and analysis; substation automation; and HVDC and facts. The conference featured 66 presentations, of which 35 have been catalogued separately for inclusion in this database

  12. Proceedings of the 2009 CIGRE Canada conference on power systems : innovation and renewal : building the new power system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    The Conseil International des Grands Reseaux Electriques (CIGRE) is the International Council on Large Electric Systems. It promotes technical, economic and environmental developments in electricity transmission and generation. CIGRE Canada is the Canadian National Committee which fosters the participation of Canadian members in CIGRE activities. CIGRE Canada organizes an annual conference that provides a forum for power system engineers, decision makers,economists, and academics to discuss technological developments in electrical power systems. The presentations at this conference addressed issues regarding the use of renewable energy sources in power transmission and distribution systems, with particular reference to control and protection; HVDC and MVDC; modelling tools; interface technologies; and reduced carbon generation and sustainability. The use of active distribution systems was also discussed in terms of future trends; the role of information technology and communications; and the role of energy storage. The session on smart grids addressed issues such as power utility perspectives; sensing, measurements and controls; advanced interfaces and decision support systems; open-architecture; distributed energy resources; and regulatory issues. Issues concerning the interconnection of non traditional energy sources to the power systems were also discussed along with recent research initiatives related to renewable energy source development. The sessions were entitled: smart grids; distributed energy resources; wind and solar PV; AC systems and HV lines; wide area measurements; power system operation and control; modelling and analysis; substation automation; and HVDC and facts. The conference featured 66 presentations, of which 35 have been catalogued separately for inclusion in this database. tabs., figs.

  13. The future of substation automation (protection, control, system)

    Energy Technology Data Exchange (ETDEWEB)

    Tholomier, D. [Areva T and D Automation Canada Inc., Monteal, PQ (Canada); Hossenlopp, L. [Areva T and D Automation Inc., Paris (France); Apostolov, A. [Omicron Electronics, Houston, TX (United States)

    2008-07-01

    This paper described a high-level plan for implementing wide-area control in an energy management system (EMS) designed to improve power system grid security and protect the electrical interconnection from a widespread collapse. The appropriate action in some cases would be islanding and blacking out a portion of the grid in order to prevent widespread collapse. The use of new automation solutions can address costly shortcomings in capacity, reliability, power quality and security. International organizations such as the Institute of Electrical and Electronics Engineers (IEEE), International Electrotechnical Commission (IEC) and the Conseil International des Grands Reseaux Electriques (CIGRE) launched several working groups to analyze the context of major blackouts and develop concepts for the use of new technologies and coordinated investment strategies to modernize the power system infrastructure. The main benefits of such smart grid systems would be: no wide-area blackouts, far fewer localized disruptions, and faster recovery when disruptions do occur; greater security from self-healing technologies and better real-time monitoring and response; high-quality power needed for sensitive electronics and computer applications; and new options for consumers to manage their electricity use and costs. The authors noted that in order to gain the full advantages of the new IEC 61850 standard there is a need to change project execution processes and prioritize various changes. This paper demonstrated the importance of system design and outlined some system engineering and interoperability tests aspects. 17 figs.

  14. Proceedings of the 2008 CIGRE Canada conference on power systems : technology and innovation for the Canadian power grids of the future

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    The Conseil International des Grands Reseaux Electriques (CIGRE) promotes technical, economic and environmental developments in electricity transmission and generation. CIGRE Canada is one of 53 national committees of CIGRE. This conference showcased Canadian contributions to the electric power industry and how technology and innovation in the future will influence North American power grids. It provided a forum to discuss technological developments in the electric power industry and present products and services for electrical power systems. Issues concerning the interconnection of non traditional energy sources to the power systems were also discussed along with recent research initiatives related to renewable energy source development. The sessions of the conference were entitled: wind reliability and forecasting; substation automation and communication; human resources and long range planning; power system protection and control; distributed generation; electric vehicles and renewable energy; HVDC and facts; modeling and simulation; markets; overhead transmission lines; and new sensor and de-icing technologies and data management systems. All 68 presentations featured at this conference have been catalogued separately for inclusion in this database. refs., tabs., figs.

  15. Towards the development of a regional electricity market in Central Africa: Issues and Challenges; Vers la realisation d'un marche regional de l'electricite en Afrique Centrale: Enjeux et defies

    Energy Technology Data Exchange (ETDEWEB)

    Veilleux, Rheaume; Mbadinga, David; Kitoko Senghi, Laurent

    2010-09-15

    This article gives a short description of the African continent. It then describes the 5 energy pools covering 54 countries: COMELEC, SAPP, WAPP, PEAC, EAPP. More specifically, the article looks at the main strategies and methods to be put in place in order to implement the electricity market, in particular the regional market of Central Africa. The current interconnecting projects and studies between different African countries, made by RSW international in collaboration with different partners, are presented, and in a more comprehensive way, the one related to the Interconnexion of the electrical networks of the member countries of the ECCAS. [French] Cet article presente une courte description du continent africain. Par la suite, on decrit les 5 pools energetiques couvrant les 54 pays : COMELEC, SAPP, WAPP, PEAC, EAPP. Plus specifiquement, on aborde les principales strategies et moyens a mettre en place pour implanter et developper le marche de l'electricite, plus particulierement le marche regional de l'Afrique centrale. Les projets ou etudes d'interconnexion en cours entre differents pays de l'Afrique, realises par RSW International de concert avec differents partenaires, sont presentes et, de facon plus exhaustive, celle relative au projet de l'Interconnexion des Reseaux Electriques des Pays Membres de la CEEAC.

  16. Proceedings of the 2008 CIGRE Canada conference on power systems : technology and innovation for the Canadian power grids of the future

    International Nuclear Information System (INIS)

    2008-01-01

    The Conseil International des Grands Reseaux Electriques (CIGRE) promotes technical, economic and environmental developments in electricity transmission and generation. CIGRE Canada is one of 53 national committees of CIGRE. This conference showcased Canadian contributions to the electric power industry and how technology and innovation in the future will influence North American power grids. It provided a forum to discuss technological developments in the electric power industry and present products and services for electrical power systems. Issues concerning the interconnection of non traditional energy sources to the power systems were also discussed along with recent research initiatives related to renewable energy source development. The sessions of the conference were entitled: wind reliability and forecasting; substation automation and communication; human resources and long range planning; power system protection and control; distributed generation; electric vehicles and renewable energy; HVDC and facts; modeling and simulation; markets; overhead transmission lines; and new sensor and de-icing technologies and data management systems. All 68 presentations featured at this conference have been catalogued separately for inclusion in this database. refs., tabs., figs

  17. Absorption by water vapour in the 1 to 2 μm region

    International Nuclear Information System (INIS)

    Smith, K.M.; Ptashnik, I.; Newnham, D.A.; Shine, K.P.

    2004-01-01

    The near-IR (in the range 5000-10 000 cm -1 , 1-2 μm) bands of water vapour have been measured in absorption in the laboratory at sub-Doppler spectral resolution (up to 0.0054 cm -1 after numerical apodisation) by Fourier transform spectroscopy. Measurements have been made at 296 K on pure water vapour (at pressures between 2 and 20 hPa) and mixtures of water and air (at total pressures of 100 and 1000 hPa), at optical path lengths in the range 0.26-9.75 m. Measured absorption intensities have been compared with values calculated using the HITRAN 2000 molecular database. These comparisons indicate that the intensities of the 2ν(1.4 μm) and 2ν+δ(1.14 μm) bands are underestimated in HITRAN 2000 by approximately 15% and 20%, respectively, for pure water vapour measurements, and 12% for both bands in the case of water-air mixtures. The ν+δ (1.86 μm) band is in good agreement (0.4% for pure water vapour and less than 6% for mixtures with air) with HITRAN 2000. For typical atmospheric conditions, these absorption bands are sufficiently strong that radiation is fully absorbed at wavelengths in the region of the band centres. Hence the extra absorption that has been identified has only a modest impact (0.16 W m -2 or about 0.2%) on the global-mean clear-sky absorption of solar radiation. The impact in the upper troposphere is several times larger

  18. Efficient injection from large telescopes into single-mode fibres: Enabling the era of ultra-precision astronomy

    Science.gov (United States)

    Jovanovic, N.; Schwab, C.; Guyon, O.; Lozi, J.; Cvetojevic, N.; Martinache, F.; Leon-Saval, S.; Norris, B.; Gross, S.; Doughty, D.; Currie, T.; Takato, N.

    2017-08-01

    Photonic technologies offer numerous advantages for astronomical instruments such as spectrographs and interferometers owing to their small footprints and diverse range of functionalities. Operating at the diffraction-limit, it is notoriously difficult to efficiently couple such devices directly with large telescopes. We demonstrate that with careful control of both the non-ideal pupil geometry of a telescope and residual wavefront errors, efficient coupling with single-mode devices can indeed be realised. A fibre injection was built within the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument. Light was coupled into a single-mode fibre operating in the near-IR (J - H bands) which was downstream of the extreme adaptive optics system and the pupil apodising optics. A coupling efficiency of 86% of the theoretical maximum limit was achieved at 1550 nm for a diffraction-limited beam in the laboratory, and was linearly correlated with Strehl ratio. The coupling efficiency was constant to within 40% for 84% of the time and >50% for 41% of the time. The laboratory results allow us to forecast that extreme adaptive optics levels of correction (Strehl ratio >90% in H-band) would allow coupling of >67% (of the order of coupling to multimode fibres currently) while standard levels of wavefront correction (Strehl ratio >20% in H-band) would allow coupling of >18%. For Strehl ratios <20%, few-port photonic lanterns become a superior choice but the signal-to-noise, and pixel availability must be considered. These results illustrate a clear path to efficient on-sky coupling into a single-mode fibre, which could be used to realise modal-noise-free radial velocity machines, very-long-baseline optical/near-IR interferometers and/or simply exploit photonic technologies in future instrument design.

  19. Formação de professores: licenciaturas, currículos e políticas

    Directory of Open Access Journals (Sweden)

    Bernardete Gatti

    2015-08-01

    Full Text Available O artigo associa questões humanas emergentes na contemporaneidade com aimportância dos processos educacionais. Nos anos vindouros, cada vez mais oacesso e o domínio de conhecimentos relevantes socialmente associam-se adomínio de linguagens, ciências, tecnologias, e à construção moral e ética. Aimportância da escola e dos professores nesse processo é ressaltada. Um olharcrítico sobre a realidade educacional brasileira, através de seus dados e realizações,conduz à discussão da demanda de professores nas redes de ensino e dasdemandas que lhes são postas, no confronto com a formação que lhes é propiciadanos cursos de licenciatura. Palavras-chave: Formação de professores; Políticas educacionais; Currículos;Licenciatura. L’article associe les conditions qui émergent dans la situation humainecontemporaine avec l’importance des processus educationelles. Dans les années àvenir, chaque foi plus, le domaine de connaissances importants pour la viequotidienne et des citoyens seront associés à la compréhension des langages, dessciences, des technologies, et à la formation morale et éthique. Alors, l’importancede l’école et des maîtres dans ce processus est decelé. Um coup d’oeil critique estlancé sur la réalité de l’éducation scolaire au Brésil conduisant à la discussion sur lademande de maîtres dans les reseaux d’enseignement e sur sa formation dans descours universitaires. Mots-clés: Formation de maîtres; Politiques éducacionelles; Curriculum scolaire;Licence.

  20. Magnetic properties of Kramers rare earth ions in aluminium and gallium garnets; Proprietes magnetiques des ions de kramers des terres rares dans les grenats de terres rares et d'aluminium et les grenats de terres rares et de gallium

    Energy Technology Data Exchange (ETDEWEB)

    Capel, H. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    The magnetic properties of Kramers rare earth ions in aluminium and gallium garnets (MAlG and MGaG) are discussed by means of a molecular field treatment. The symmetry properties of the space group permit to establish a parametrization for the magnetic dipolar and exchange couplings. The magnetic properties of the system can be expressed in terms of these parameters and the g factors of the rare earth ions. We have calculated the transition temperatures, the sub-lattice magnetizations, the susceptibility in the paramagnetic region and the antiferromagnetic susceptibility for a special type of magnetic ordering. The influence of the excited Kramers doublets is described by means of a generalization of the usual g tensor. (authors) [French] Les proprietes magnetiques des ions de Kramers des terres rares dans les grenats de terre rare et d'aluminium et les grenats de terre rare et de gallium sont discutees a l'aide d'un traitement du champ moleculaire. Les proprietes de symmetrie du groupe d'espace permettent d'exprimer les couplages dipolaires et les interactions d'echange en fonction de quelques parametres. Les proprietes magnetiques peuvent etre exprimees en fonction de ces parametres et les facteurs g des ions de terre rare. Nous avons calcule les temperatures de transition, les aimantations des sous-reseaux pour 0

  1. Instrumental concept and preliminary performances of SIFTI: static infrared fourier transform interferometer

    Science.gov (United States)

    Hébert, Philippe-Jean; Cansot, E.; Pierangelo, C.; Buil, C.; Bernard, F.; Loesel, J.; Trémas, T.; Perrin, L.; Courau, E.; Casteras, C.; Maussang, I.; Simeoni, D.

    2017-11-01

    The SIFTI (Static Infrared Fourier Transform Interferometer) instrument aims at supporting an important part in a mission for atmospheric pollution sounding from space, by providing high spectral resolution and high Signal to Noise Ratio spectra of the atmosphere. They will allow to resolve tropospheric profiles of ozone (03) and carbon monoxide (C0), especially down to the planetary boundary layer (PBL), an altitude region of very high interest, though poorly monitored to date, for air quality and pollution monitoring. The retrieved profile of ozone, resp. C0, will contain 5 to 7, resp. 2.5 to 4, independent pieces of information. The French space agency CNES (Centre National d'Etudes Spatiales) has proposed and is studying an instrument concept for SIFTI based on a static interferometer, where the needed optical path are generated by a pair of crossed staircase fixed mirrors (replacing the moving reflector of dynamic Fourier transform interferometers like IASI or MIPAS). With the SIFTI design, a very high spectral resolution ( 0.1 cm-1 apodised) is achieved in a very compact optical setup, allowing a large throughput, hence a high SNR. The measurements are performed in the 9.5 μm band for 03 and in the 4.6 μm band for C0. The science return of the sounder can be further increased if an "intelligent pointing" process is implemented. This consists in combining the TIR sounder with a companion TIR imager, providing information on the cloud coverage in the next observed scene. 0nboard, real-time analysis of the IR image is used to command the sounder staring mirror to cloud free areas, which will maximize the probability for probing down to the surface. After the first part of the phase A, the architecture of SIFTI was studied as a trade-off between performance and resource budget. We review the main architecture and functional choices, and their advantages. The preliminary instrument concept is then presented in its main aspects and in terms of main subsystem

  2. Foreword

    Science.gov (United States)

    Carbillet, M.; Ferrari, A.; Aime, C.

    This book reports the proceedings of the third Journées d'Imagerie à Très Haute Dynamique et Détection d'Exoplanètes (Days on High Contrast Imaging and Exoplanets Detection) that were held in Nice and Fréjus in May, 16th 19th, 2005, with the joint efforts of the CNRS (Centre National de la Recherche Scientifique), the Observatoire de la Côte d'Azur, the Collège de France, and the Laboratoire Universitaire d'Astrophysique de Nice of the University of Nice Sophia Antipolis. The first and second Journées led to the publications of Volumes 8 and 12 of EAS Publications Series sharing the common title “Astronomy with High Contrast Imaging”. Volume 8, subtitled “From Planetary Systems to Active Galactic Nuclei” collected 33 papers covering the very large domain of applications of High Contrast Imaging, from protoplanetary disks to AGNs. Volume 12, subtitled “Instrumentation for Coronagraphy and Nulling Interferometry” collected 29 papers dealing with technical aspects of the various experiments (apodisation, coronagraphy, nulling) that can lead to exoplanetographs, i.e. instruments able to directly record the light coming from planets orbitings stars other than the Sun. The present edition, third of these series on High Contrast Imaging, focuses on the aspects of image processing related to coronagraphy and nulling. Technologies in competition are numerous, either from the point-of-view of the methods (coronagraphy, nulling, traditional interferometry, interferometry with densified pupils, etc.), the spectral domain (observations from the visible to 10 μm), or the instrumentation (ground-based with the support of adaptive optics vs. space-born). Which techniques and instruments are the most efficient for a given astronomical objective? The answer to this question must definitely also take into account the data processing retained for each instrument and a precise analysis of the related signal-to-noise ratio. This school gathered basic lessons on

  3. Foreword

    Science.gov (United States)

    Aime, C.; Soummer, R.

    This book reports the proceedings of the second Journées d'Imagerie grave{a} Très Haute Dynamique et Détection d'Exoplanètes (Days on High Contrast Imaging and Exoplanets Detection) that were held in Nice in October, 6-10, 2003 with the joint efforts of the Collège de France, the Observatoire de la Côte d'Azur, the CNRS (Centre National de la Recherche Scientifique) and the Laboratoire Universitaire d'Astrophysique de Nice which organized the meeting. The first Journées led to the publication of Volume 8, 2003 EAS Publications Series: Astronomy with High Contrast Imaging: From Planetary Systems to Active Galactic Nuclei that collected 33 papers presented during the session of May, 13-16, 2002. It covered a very large domain of research in high contrast imaging for exoplanet detection: astrophysical science (from protoplanetary disks to AGNs), instruments and techniques (from coronagraphy to nulling), data processing. These Journées took place because of the need of a working session giving enough time to the participants to explain their work and understand that of their colleagues. The second Journées took the form of an École thématique du CNRS. The courses were held in French, but the reports are in English. The present edition reports 29 courses and short presentations given at this occasion. The texts correspond to original presentations, and a few communications, too similar to those of 2002, were not reported here to avoid duplication. This makes the two books complementary. The general theme of the school was similar to that of the former meeting, with a marked teaching objective. The courses and presentations were also more centered in optics and instrumental techniques. The main idea was to study what we could call “exoplanetographs”, instruments using apodisation, coronagraphy, nulling or other techniques to directly record the light of an exoplanet. Fundamental aspects of signal processing were deferred to a third edition of the school. A

  4. ATES Contribution to the Housing Energy Balance: a Simple Assessment Methodology Contribution du stockage d’énergie thermique en aquifère au bilan énergétique lié à l’habitat : méthodologie d’évaluation rapide

    Directory of Open Access Journals (Sweden)

    Bourbiaux B.

    2011-02-01

    Full Text Available The reduction of Green-House Gas Emissions (GHGE goes through a sum of solutions that need to be tuned to the local context in terms of energy needs and resources, and also to the demand and offer variations with time. The housing heat consumption is particularly concerned as it is seasonal and rarely in phase with the deliverability of alternative or renewable energy sources. This paper studies heat storage in saline untapped aquifers as a solution to overcome the time lag between production and consumption. This process applies to heat networks that supply dense housing complexes. Firstly, a methodology is described to size an Aquifer Thermal Energy Storage (ATES project as a function of the heat production and consumption characteristics on the one hand, and of the recovery factor of the stored heat on the other hand. The major role played by this recovery factor leads to a review of thermal losses of various origins and to a sensitivity study of influent reservoir parameters such as the aquifer thickness, productivity and heterogeneity, for the purpose of aquifer selection and storage project management. La reduction des Gaz a Effet de Serre (GES passe par un ensemble de solutions qui doivent etre adaptees au contexte local des besoins et ressources en energie, ainsi qu’aux variations de l’offre et la demande au cours du temps. Ce constat concerne en particulier la consommation d’energie calorifique destinee a l’habitat. En effet, cette consommation de chaleur est saisonniere et rarement en phase avec la disponibilite des sources d’energie alternatives ou renouvelables. Cet article etudie le stockage de chaleur dans des aquiferes salins inexploites en tant que solution pour pallier ce dephasage entre production et consommation. Ce procede concerne les reseaux de chaleur desservant un habitat concentre. En premier lieu, une methodologie quantitative est decrite pour dimensionner le projet de stockage d’energie thermique en

  5. Le changement comme tradition dans la recherche et la formation a la recherche en biotechnologie et en peripherie Etude de cas en sciences de la sante, sciences naturelles et genie

    Science.gov (United States)

    Bourque, Claude Julie

    luttes universitaires que scientifiques, concentrees sur la negociation du capital scientifique, symbolique et economique en jeu dans la formation doctorale, dans les carrieres auxquelles elle mene, et dans les qualites du titre de Ph.D. Au final, la confusion entre des logiques opposees peut etre reduite en reinterpretant le changement comme tradition du champ scientifique. Mots-cles Sociologie, education, enseignement superieur, science et technologie, biotechnologie, formation doctorale, champ scientifique, reseaux sociaux

  6. Study of the crystallographic and magnetic properties of cubic manganite spinels NiMn{sub 2}O{sub 4}; Etude des proprietes cristallographiques et magnetiques des manganites spinelles cubiques NiMn{sub 2}O{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Boucher, B. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    We study the variation of the crystallographic properties (inversion degree, position parameters and short range order) of the cubic spinel Mn{sub {nu}}Ni{sub 1-{nu}}[Mn{sub 2{nu}}Ni{sub {nu}}]O{sub 4}, as a function of the thermal treatment applied to the sample. {nu} lies between 0. 74 and 0. 93; the slower the sample is cooled the more inverse it is. We show, in a molecular field theory, that a system of three magnetic sublattices can afford a 'star' configuration. We establish the conditions of stability of such a structure and its evolution as a function of temperature is foreseen. Neutron diffraction measurements show that the magnetic structure of NiMn{sub 2}O{sub 4} at 4.2 K is a 'star' configuration and that with increasing temperature it becomes a collinear structure in agreement with the theory. Furthermore, we find an anomaly in the value of specific heat at the transition temperature between 'star' and collinear structures. (author) [French] On etudie la variation des proprietes cristallographiques (inversion, parametre de position, ordre a courte distance) du spinelle cubique Mn{sub {nu}}Ni{sub 1-{nu}}[Mn{sub 2{nu}}Ni{sub {nu}}]O{sub 4}, en fonction du traitement thermique que subit l'echantillon, {nu} est compris entre 0,74 et 0,93; plus le corps est refroidi lentement, plus il est inverse. On montre, dans le cadre d'une theorie de champ moleculaire, qu'un systeme a trois sous-reseaux magnetiques peut presenter une configuration en ''etoile''. On etablit les conditions de stabilite d'une telle structure et on prevoit son evolution en fonction de la temperature. Les mesures de diffraction de neutrons montrent que la structure magnetique de NiMn{sub 2}O{sub 4} a 4,2 K est du type ''en etoile'' et qu'elle evolue en fonction de la temperature vers une structure colineaire comme le prevoit la theorie. De plus on observe une anomalie de chaleur specifique a la

  7. Application of the pulsed neutron technique on the reactors ALIZE - AQUILON (1963); Application de la methode des neutrons pulses sur les piles ALIZE et AQUILON (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Jacquemart, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    affectes par la sensibilite spectrale des absorbants. Une methode modifiee utilisant la technique des neutrons pulses a ete experimentee. Les experiences sous-critiques ont permis de definir avec une bonne precision des tailles critiques de reseaux uranium-eau lourde. (auteur)

  8. Contribution to the study of the role of diffusion in the growth of crystals from solution; Contribution a l'etude du role de la diffusion dans la croissance des cristaux a partir de solution

    Energy Technology Data Exchange (ETDEWEB)

    Quivy, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-12-01

    In the case of the two-dimensional growth of crystals from solution, the concentration distribution could be explained on the basis of Fick diffusion equation. The limiting conditions are defined in a satisfactory way, and the curves of equal concentration in the solution surrounding the crystal are calculated using a resistance network device. These curves are similar to the observed interference fringes. The limiting conditions are different according as to whether the type of crystal growth is regular or dendritic. In this work the growth rate of the crystal faces in solution has been measured for various substances. These direct measurements were carried out using a micrometric eye-piece and chrono-photographs. The interferential method using polarized light has been used for determining the concentration distribution in the neighbourhood of the crystal; it was thereby possible, knowing the diffusion coefficient, to calculate the growth rate and to observe the existence of a disagreement, of the order of two, with the direct measurements. This discrepancy can even attain a value of ten in the case of very soluble substances; these latter have been studied by R. ITTI. (author) [French] Dans le cas de la croissance a deux dimensions de cristaux a partir de solution, la distribution des concentrations pouvait etre expliquee a partir de l'equation de diffusion de FICK. En fixant les conditions aux limites de facon convenable, on calcule, au moyen d'un dispositif a reseaux resistifs, les courbes d'egale concentration de la solution entourant le cristal. On constate que ces courbes sont semblables aux franges d'interferences observees. Les conditions aux limites sont differentes suivant que le type de croissance du cristal est regulier ou dendritique. Dans ce travail, on a egalement mesure les vitesses de croissance des faces cristallines a partir de solutions, en employant differentes substances. Ces mesures directes ont ete effectuees au moyen d

  9. Diferenciación étnica y redes de larga distancia entre migrantes andinos: el caso de Sanka y Colcha

    Directory of Open Access Journals (Sweden)

    1991-01-01

    Full Text Available DIFFERENTIATION ETHNIQUE ET RESEAUX DE LONGUE DISTANCE CHEZ LES MIGRANTS ANDINS : LE CAS DE “SANKA” ET “COLCHA”. Les migrants andins ne limitent pas leurs réseaux sociaux d’interaction au milieu urbain. La réorientation spatiale des migrants devient notable au moment de l’aggravation de la crise nationale au Pérou qui affecte avec une particulière dureté la population liménienne. La formation de nouveaux réseaux de longue distance entre migrants est déterminée historiquement par l’espace géographique que couvre l’histoire de leur migration. De tels réseaux d’interaction impliquent un mécanisme spécifique de reproduction sociale des migrants andins et constituent un facteur important de changement social. Los migrantes andinos en Lima no limitan sus redes sociales de interacción al centro urbano. Sobre todo con la agudización de la crisis nacional en el Perú, que afecta con particular dureza a la población limeña, comienza una notable reorientación espacial de los migrantes. La formación de nuevas redes de larga distancia entre migrantes es históricamente determinada por el espacio geográfico que cubre su historia migracional. Tales redes de interacción significan un mecanismo específico de reproducción social de migrantes andinos y son factor importante del cambio social. ETHNIC DIFFERENTIATION AND LONG-DISTANCE-NETWORKS BETWEEN ANDEAN MIGRANTS: THE CASE OF “SANKA” AND “COLCHA”. The andean migrants in Lima do not limit their social networks of interaction on the urban center. Together with the aggravation of the national crisis in Peru, which affects the urban population of Lima particularly hard, is emerging a remarkable spatial reorientation of those migrants. The formation of long-distance-networks between migrants is historically determined by the geographical space, which covers their migration history. Such networks of interaction suggest a specific form of social reproduction of the andean migrants

  10. The Verrès Castle Access Project

    Directory of Open Access Journals (Sweden)

    Tito Berti Nulli

    2010-10-01

    Full Text Available The article describes the access project of the Verrès castle, located in Aosta Valley in Italy, underlining some urban and transport planning and design elements. This project constitute in fact an interesting example of integration between transport infrastructure planning and design with urban planning strategy for tourism development. The transport infrastructure (in this case a vertical lift for tourism use has furthermore a deep attention to the landscape and social contest and a good architectural design. The Verrès castle access project represents and interesting example of sustainable mobility and of touristic area accessibility which is strong integrated with urban renewal and territorial development. The feasibility study, financed by the Verrès municipality, is part of a the INTERREG IIIA ACOLTRA Project financed by Italy and France with the aim of creating a network of transnational tourist itineraries. Through this initiative Aosta Valley and Haute-Savoy are developing a common tourism strategy that intends to promote cultural heritage and tourism mobility through the RITT (Reseaux d’Itineraires Touristiques Transfrontalieres. In this contest of intervention the study for the accessibility of the Verrès castle is inserted, with the aim of designing a mobility infrastructure for the main attraction of the valley and at the same of strengthening the appeal of tourist attraction of the whole area. The project is located in the small city of Verrés, that lies at 390m, on the banks of the river Evançon. As many of the Valdostani municipalities is characterized by several small urban centers, which are located in a around 8kmq, in a territory where live 2.700 inhabitants. The feasibility study examines three different alternative for a lift that should connect the Verrès centre with the castle. In particular different transport technology (inclined and vertical lift and several path alternatives have been evaluated. The final

  11. Les cooperatives et l'electrification rurale du Quebec, 1945--1964

    Science.gov (United States)

    Dorion, Marie-Josee

    dans l'electrification, les organismes publics et les compagnies privees d'electricite. Cette periode de demarrage et d'organisation, traitee dans la deuxieme partie de la these, se termine en 1947-48, au moment ou l'OER et les cooperatives raffermissent leur maitrise du systeme cooperatif d'electrification rurale. Les annees 1948 a 1955 (troisieme partie de these) correspondent a une periode de croissance pour le mouvement cooperatif. Cette partie scrute ainsi le developpement des cooperatives, les vastes chantiers de construction et l'injection de millions de dollars dans l'electrification rurale. Cette troisieme partie prend egalement acte des premiers signes que quelque chose ne va pas si bien dans le monde cooperatif. Nous y verrons egalement les ruraux a l'oeuvre: comme membres, d'abord, mais aussi en tant que benevoles, puis a l'emploi des cooperatives. La quatrieme et derniere partie, les annees 1956 a 1964, aborde les changements majeurs qui ont cours dans l'univers cooperatif; il s'agit d'une ere nouvelle et difficile pour le mouvement cooperatif, dont les reseaux paraissent inadaptes aux changements de profil de la consommation d'electricite des usagers. L'OER sent alors le besoin de raffermir son controle des cooperatives, car il pressent les problemes et les defis auxquels elles auront a faire face. Notre etude se termine par l'acquisition des cooperatives par Hydro-Quebec, en 1963-64. Fondee sur des sources riches et variees, notre demarche propose un eclairage inedit sur une dimension importante de l'histoire de l'electricite au Quebec. Elle permet, ce faisant, de saisir les rouages et l'action de l'Etat sous un angle particulier, avant sa profonde transformation amorcee au cours des annees 1960. De meme, elle apporte quelques cles nouvelles pour une meilleure comprehension de la dynamique des milieux ruraux de cette periode.

  12. Restauration adaptative des contours par une approche inspiree de la prediction des performances

    Science.gov (United States)

    Rousseau, Kami

    effectuee et permet de mieux comprendre la contribution de chaque indicateur. L'efficacite de l'outil developpe est comparable a celle d'autres methodes de detection de contours et en fait un choix interessant pour la detection de contours. Les differences de qualite observees entre notre methode et celle de Canny semble etre dues a l'utilisation, ou non, de post-traitements. Grace au logiciel developpe, il est possible de reutiliser la methodologie; cette derniere a permis d'operationnaliser la methode proposee. La possibilite de reutiliser le filtre, sans reentrainement est interessante. La simplicite du parametrage lors de l'utilisation est aussi un avantage. Ces deux facteurs repondent a un besoin de reduire le temps d'utilisation du logiciel. Mots-cles: detection de signal adaptative, caracterisation des performances, reseaux de neurones, imagerie panchromatique, analyse de contours.