Download or read book CONTRIBUTION A L ETUDE DE LA FIABILITE MECANIQUE DES FIBRES OPTIQUES written by NOELLA.. EVANNO and published by . This book was released on 1999 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'UTILISATION DE LA FIBRE OPTIQUE JUSQUE CHEZ L'ABONNE NECESSITE UN ALLEGEMENT DE LA STRUCTURE DU CABLE. CELUI-CI SE TRADUIT EN PRATIQUE PAR UNE EXPOSITION BEAUCOUP PLUS SEVERE DE LA FIBRE AUX CONTRAINTES EXTERIEURES. CE TRAVAIL CONSISTE A ETUDIER L'INFLUENCE DE L'ENVIRONNEMENT SUR LES PROPRIETES MECANIQUES DE LA FIBRE AFIN DE PROPOSER UN MODELE PERMETTANT D'EVALUER LA DUREE DE VIE D'UNE FIBRE SOUMISE A DES CONDITIONS SEVERES D'UTILISATION. LE MODELE OPTIMISE DE MITSUNAGA ETAIT JUSQU'A PRESENT LE MODELE LE PLUS ADEQUAT POUR L'EVALUATION DE LA DUREE DE VIE DES FIBRES. MAIS DANS LE CAS D'UNE SOLLICITATION SEVERE DE LA FIBRE CE MODELE PRESENTE DES LIMITES, CAR IL NE TIENT PAS COMPTE DE L'ENVIRONNEMENT. LES ESSAIS DE FATIGUE REALISES DANS DIVERS MILIEUX AGRESSIFS MONTRENT QUE LES PARAMETRES DE FATIGUE DE LA FIBRE SONT TRES SENSIBLES A L'ENVIRONNEMENT, EN PARTICULIER A LA TEMPERATURE ET A L'HUMIDITE. LES RESULTATS OBTENUS ONT PERMIS DE DETERMINER L'EVOLUTION DE CES PARAMETRES AVEC LES FACTEURS ENVIRONNEMENTAUX. L'INTRODUCTION DE CES LOIS D'EVOLUTION DANS LE MODELE OPTIMISE DE CALCUL DE LA DUREE DE VIE PERMET DE PRENDRE EN COMPTE L'INFLUENCE DE L'ENVIRONNEMENT DANS L'EVALUATION DE LA FIABILITE DE LA FIBRE. LE TEMPS D'UTILISATION EST EGALEMENT UN FACTEUR DETERMINANT DANS L'EVALUATION DE LA FIABILITE A LONG TERME DE LA FIBRE. LES ESSAIS DE VIEILLISSEMENT MONTRENT UNE DEGRADATION DE SA RESISTANCE AVEC LE TEMPS, QUI EST LE RESULTAT DE LA PROPAGATION DES DEFAUTS PRESENTS A LA SURFACE DE LA SILICE ET DE L'INITIATION DE NOUVEAUX DEFAUTS. LA PRISE EN COMPTE DE CETTE DEGRADATION DANS LE MODELE OPTIMISE DE CALCUL DE LA DUREE DE VIE PERMET MAINTENANT D'EVALUER LA FIABILITE DE LA FIBRE AU COURS DE SON EXPLOITATION EN FONCTION DE LA CONTRAINTE ET DE L'ENVIRONNEMENT. L'UTILISATION DE CE MODELE DEVRAIT PERMETTRE DE DIMINUER LES COUTS D'INFRASTRUCTURE PAR UNE CONNAISSANCE PLUS FINE DE LA FIABILITE DES LIAISONS PAR CABLES OPTIQUES AINSI QUE LES COUTS DE MAINTENANCE DES RESEAUX DE TELECOMMUNICATION PAR UNE OPTIMISATION DU RENOUVELLEMENT DES LIGNES DE TRANSMISSION.

Download or read book FIABILITE MECANIQUE DES FIBRES OPTIQUES written by CYRIL.. COCQ and published by . This book was released on 1999 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: POUR GARANTIR UNE BONNE FIABILITE DU RESEAU, IL EST NECESSAIRE DE PREVOIR LA DUREE DE VIE DES FIBRES OPTIQUES ET DONC D'AVOIR DES LOIS CONNUES ET UTILISABLES. LA FIABILITE DES FIBRES OPTIQUES DEPEND, EN GRANDE PARTIE, DE LA TENUE MECANIQUE DES FIBRES. CELLES-CI DOIVENT RESISTER A DES CONTRAINTES TRES DIVERSES, LORS DE LEUR CABLAGE, INSTALLATION ET EXPLOITATION. DE PLUS, LA CORROSION SOUS CONTRAINTE, DUE A L'HUMIDITE, ENTRAINE UNE DEGRADATION DE LA RESISTANCE MECANIQUE EN FONCTION DU TEMPS ET PEUT RACCOURCIR CONSIDERABLEMENT LA DUREE DE VIE DES FIBRES. NOUS AVONS APPLIQUE LA MECANIQUE DE LA RUPTURE AU CAS DES FIBRES OPTIQUES ET NOUS AVONS INTRODUIT LE CONCEPT DE DEFAUT QUI PERMET D'ETUDIER ET MODELISER LA DUREE DE VIE DE LA FIBRE. LES CONTRAINTES RESIDUELLES PRESENTES DANS LA FIBRE ONT FAIT L'OBJET D'UNE ETUDE BIBLIOGRAPHIQUE. DIFFERENTS ESSAIS EXPERIMENTAUX SONT EFFECTUES SUR LA FIBRE OPTIQUE. NOUS AVONS COMPARE CES RESULTATS ENTRE LA FIBRE MONOCOEUR ET LA FIBRE MULTICOEUR ET SUIVANT LE TYPE D'ESSAIS EFFECTUE. LA SILICE EST UN MATERIAU FRAGILE ET LES RESULTATS MONTRENT UN CARACTERE PROBABILISTE. NOUS INTRODUISONS DONC LA THEORIE DU MAILLON LE PLUS FAIBLE QUI REGIT LA RESISTANCE MECANIQUE DE LA FIBRE OPTIQUE. LES LOIS DE DUREE DE VIE UTILISEES SONT PRESENTEES AINSI QU'UNE METHODOLOGIE POUR CALCULER TOUS LES PARAMETRES DE LA LOI D'EVANS/WIEDERHORN AINSI QUE LES PARAMETRES DE WEIBULL EN MILIEU INERTE. LES MODELES DE DUREE DE VIE UTILISES SUIVANT DES SOLLICITATIONS DE TRACTION ET DE COURBURE ONT PERMIS D'OBTENIR UNE LOI NOUS PERMETTANT D'ETUDIER LA FIABILITE DES FIBRES OPTIQUES MONOCOEUR ET MULTICOEUR.

Download or read book CONTRIBUTION A L EVOLUTION DES TECHNIQUES DES COMMUNICATIONS OPTIQUES written by ALCIBIADE.. ZAGANIARIS and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: LES DEUX VOLETS DE CETTE THESE SONT LA MISE AU POINT DE METHODES DE CARACTERISATION DES MATERIAUX POUR FIBRES OPTIQUES ET L'ETUDE TECHNICO-ECONOMIQUE DES SYSTEMES OPERATIONNELS... ON DEBUT PAR UNE DESCRIPTION D'UN ENSEMBLE DE METHODES THERMIQUES POUR MESURER LES DEUX COMPOSANTES D'ATTENUATION DE LA LUMIERE DANS LES MATERIAUX MASSIFS DE DEPART ET DANS LES FIBRES: L'ABSORPTION ET LA DIFFUSION. POUR CELA ON EXPLOITE LA THERMOCINETIQUE DIFFERENTE DE CES PHENOMENES. ENSUITE ON EXAMINE LES FACTEURS QUI LIMITENT LA DUREE DE VIE D'UNE FIBRE EN EXPLOITATION ET ON PROPOSE DES METHODES DE MESURE DES DIFFERENTS PARAMETRES DE LA FIBRE. L'ENSEMBLE DE CES ETUDES DE FIABILITE FOURNIT LA BASE THEORIQUE ET PRATIQUE NECESSAIRE A UNE BONNE CONNAISSANCE DU COMPORTEMENT MECANIQUE DES FIBRES. LES TESTS MIS AU POINT ONT PERMIS D'EXPRIMER LA DUREE DE VIE DES FIBRES EN FONCTION DE LA CONTRAINTE PERMANENTE EN SERVICE ET DE CONSTANTES CARACTERISTIQUES DU MATERIAU. ENFIN, ON EXAMINE LE RESEAU LOCAL DANS SON ENSEMBLE SOUS L'ASPECT TECHNICO-ECONOMIQUE. ON COMPARE LE COUT ACTUALISE DES DIFFERENTES SOLUTIONS TECHNIQUES PENDANT TOUTE LA VIE DU RESEAU. ON ETABLIT AINSI DES SCENARIOS REALISTES D'INTRODUCTION DE RESEAUX OPTIQUES. CES RESULTATS SONT COMPLETES PAR UNE ANALYSE DE SENSIBILITE DU COUT GLOBAL AUX PRINCIPAUX PARAMETRES D'INSTALLATION

Download or read book Etude et r alisation d un microscope de champ proche optique avec asservissement de type shear force written by Lotfi Berguiga and published by . This book was released on 2001 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dans le cadre d'utilisation des fibres optiques dans les réseaux FTTH (Fiber To The Home) et FTTB (Fiber To The Building), celles-ci subissent des contraintes et un environnement plus sévères que les fibres placées dans les réseaux actuels, c'est à dire les réseaux sous-marins et les réseaux enterrés. La fibre optique subit au cours du temps une modification de ses propriétés mécaniques, dûe à la diffusion d'eau à travers le revêtement polymère qui protège la fibre. Cette présence d'eau à l'interface silice-revêtement entraîne une modification de l'état de surface de la fibre optique. A cet effet dans ce travail de thèse nous avons développé un dispositif expérimental permettant l'étude à l'échelle nanométrique de la surface de silice des fibres optiques. Il s'agit d'un microscope de champ proche optique avec une régulation de type " shear force ". Cette technique fournit une information double, une information topographique et une information de nature optique. Dans un premier temps, nous présentons les notions concernant les propriétés mécaniques des fibres et les techniques de caractérisation s habituelles dans le domaine de la fiabilité. Ensuite, le dispositif de champ proche optique mis au point est détaillé, en particulier la partie concernant la boucle de rétroaction utilisant la force de cisaillement...

Download or read book Power Electronic Packaging written by Yong Liu and published by Springer Science & Business Media. This book was released on 2012-02-15 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt: Power Electronic Packaging presents an in-depth overview of power electronic packaging design, assembly,reliability and modeling. Since there is a drastic difference between IC fabrication and power electronic packaging, the book systematically introduces typical power electronic packaging design, assembly, reliability and failure analysis and material selection so readers can clearly understand each task's unique characteristics. Power electronic packaging is one of the fastest growing segments in the power electronic industry, due to the rapid growth of power integrated circuit (IC) fabrication, especially for applications like portable, consumer, home, computing and automotive electronics. This book also covers how advances in both semiconductor content and power advanced package design have helped cause advances in power device capability in recent years. The author extrapolates the most recent trends in the book's areas of focus to highlight where further improvement in materials and techniques can drive continued advancements, particularly in thermal management, usability, efficiency, reliability and overall cost of power semiconductor solutions.

Download or read book MILCOM 2005 written by Institute of Electrical and Electronics Engineers and published by . This book was released on 2005 with total page 674 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dictionary of Building and Civil Engineering written by Don Montague and published by Taylor & Francis. This book was released on 1996 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dual-language dictionary lists over 20,000 specialist terms in both French and English, covering architecture, building, engineering and property terms. It meets the needs of all building professionals working on projects overseas. It has been comprehensively researched and compiled to provide an invaluable reference source in an increasingly European marketplace.

Download or read book Faecal Sludge Management written by Linda Strande and published by IWA Publishing. This book was released on 2014-08-15 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is estimated that literally billions of residents in urban and peri-urban areas of Africa, Asia, and Latin America are served by onsite sanitation systems (e.g. various types of latrines and septic tanks). Until recently, the management of faecal sludge from these onsite systems has been grossly neglected, partially as a result of them being considered temporary solutions until sewer-based systems could be implemented. However, the perception of onsite or decentralized sanitation technologies for urban areas is gradually changing, and is increasingly being considered as long-term, sustainable options in urban areas, especially in low- and middle-income countries that lack sewer infrastructures. This is the first book dedicated to faecal sludge management. It compiles the current state of knowledge of the rapidly evolving field of faecal sludge management, and presents an integrated approach that includes technology, management, and planning based on Sandecs 20 years of experience in the field. Faecal Sludge Management: Systems Approach for Implementation and Operation addresses the organization of the entire faecal sludge management service chain, from the collection and transport of sludge, and the current state of knowledge of treatment options, to the final end use or disposal of treated sludge. The book also presents important factors to consider when evaluating and upscaling new treatment technology options. The book is designed for undergraduate and graduate students, and engineers and practitioners in the field who have some basic knowledge of environmental and/or wastewater engineering.

Download or read book Adhesion Between Polymers and Concrete Adh sion Entre Polym res Et B ton written by H. R. Sasse and published by Springer. This book was released on 1986 with total page 792 pages. Available in PDF, EPUB and Kindle. Book excerpt: Preface Adhesion is a phenomenon architects and civil engineers are not very familiar with. In other disciplines knowledge about surface properties and the background of bonding energies is also far from satisfactory; nevertheless there are many important· applications in concrete engineering, where adhesion is necessary for success and durability. These include: - coating and painting - repair of concrete surfaces - bonding of fresh to old concrete - crack injection - glueing of precast elements - glueing of steel to concrete, etc. In 1981 RILEM established the technical committee 52-RAC 'Resin Adherence to Concrete'. The main aims of the committee's work were - to collect research results and practical experiences - to initiate and coordinate research programs - to develop, on a scientific base, test methods for field and for laboratory purposes. One of the results of the committee's work is a state-of-the-art report, which will be presented orally as a General Report at the International Symposium ISAP '86, and will be printed either in the RILEM journal Materials and Structures or separately. Several test recommendations have been elaborated and will be prepared as drafts for the participants ofISAP '86. These are: - direct tensile test - pull-off test - direct shear test - slant shear test - four-point bending test - dynamic loading test - thermal compatibility test (two versions) - injectibility test.

Download or read book UNESCO General History of Africa Vol I Abridged Edition written by Jacqueline Ki-Zerbo and published by Univ of California Press. This book was released on 1990 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This volume covers the period from the end of the Neolithic era to the beginning of the seventh century of our era. This lengthy period includes the civilization of Ancient Egypt, the history of Nubia, Ethiopia, North Africa and the Sahara, as well as of the other regions of the continent and its islands."--Publisher's description

Download or read book AGARD Conference Proceedings written by North Atlantic Treaty Organization. Advisory Group for Aerospace Research and Development and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Gas cooled Nuclear Reactors written by France. Commissariat à l'énergie atomique and published by . This book was released on 2006 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Research Into Spinal Deformities 7 written by Carl-Eric Aubin and published by IOS Press. This book was released on 2010 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: In choosing Montreal for its 8th biennial meeting, the International Research Society of Spinal Deformities (IRSSD), is returning to an auspicious and important venue: their 1992 meeting in Montreal marked the turning point from a focus on the morphological aspects of spinal deformity, towards three-dimensional evaluation and interpretation of scoliotic deformities and their biomechanics. Since then, the IRSSD meetings have had an instrumental role in the advancement of scientific research on problems affecting the spine. This book contains the proceedings of the 2010 conference in the form of peer-reviewed, short papers and abstracts, summarizing the 140 papers and posters presented at the Montreal meeting. With contributions from scientific and clinical experts from around the world, it covers all aspects of spinal deformity research including: etiology, genetics, biology, metabolism, biomechanics, imaging technologies, innovations in treatment and treatment outcomes. It explores current research developments, the underlying mechanisms that cause scoliosis and the clinical effectiveness of a wide range of treatments. Of interest to all those involved in the research into and treatment of spinal deformities, the book provides an opportunity to learn more about the latest developments in this field.

Download or read book Urban Water Supply and Sanitation written by and published by Allied Publishers. This book was released on 1999 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: South Asia Rural Development Series. India's economic policies are aimed at increasing economic growth, improving market efficiency and competitiveness, and integrating the Indian economy with global markets. Much of the population and industrial growth is expected to occur in urban centers. Consequently, the demands on the Urban Water Supply and Sanitation sector (UWSS), will be great. Urban Water Supply and Sanitation states the UWSS sector needs urgent attention both to meet these new demands and to ensure that all city-dwellers have access to basic services at reasonable costs. This book outlines the way forward which includes a discussion on institutional reform and financial reform as well an action plan.

Download or read book Soft Matter Physics written by Mohamed Daoud and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 335 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a liquid crystal watch, the molecules contained within a thin film of the screen are reorientated each second by extremely weak electrical signals. Here is a fine example of soft matter: molecular systems giving a strong response to a very weak command signal. They can be found almost everywhere. Soft magnetic materials used in transformers exhibit a strong magnetic moment under the action of a weak magnetic field. Take a completely different domain: gelatin, formed from col lagen fibres dissolved in hot water. When we cool below 37°C, gelation occurs, the chains joining up at various points to form a loose and highly deformable network. This is a natural example of soft matter. Going further, rather than consider a whole network, we could take a single chain of flexible polymer, such as polyoxyethylene [POE = (CH CH O)N, 2 2 5 where N rv 10 ], for example, in water. Such a chain is fragile and may break under flow. Even though hydrodynamic forces are very weak on the molecular scale, their cumulated effect may be significant. Think of a rope pulled from both ends by two groups of children. Even if each girl and boy cannot pull very hard, the rope can be broken when there are enough children pulling.

Download or read book Market Assessment Study of New Media Learning Materials written by Canada. Industry Canada and published by . This book was released on 1996 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Polymer Processing and Characterization written by Sabu Thomas and published by CRC Press. This book was released on 2012-07-23 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with the polymers, different methods of synthesis, and synthesis of composites, as well as the different techniques used for polymer characterization. Most of the world’s industries extract the anomalous properties of polymers to make excellent cost-effective materials. Because of this, the types of polymers, their processing, and the analysis of their various properties are very significant. Readers will gain a thorough knowledge about the processing of different types of polymers and composites made from them, as well as their various applications. Suitable for classroom use but especially important for researchers, this book addresses: Adhesion of amorphous polymers with vitrified bulk and surface glass transition Functionalized biopolymers and their applications A new synthesis of p-Cresol-Adipamide-Formaldehyde copolymer resin and its applications as an ion-changer Correlating performance of commercial viscosity modifiers for formulating shear stable industrial lubricants Synthesis of phthalonitrile polymers in ionic liquid and microwave media Studies on nanocomposite polymer electrolytes doped with Ca3(PO4)2 for lithium batteries