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Sample records for materiaux des composants

  1. Preface: Materiaux 2010

    NASA Astrophysics Data System (ADS)

    Cheikhrouhou, Abdelwaheb

    2012-02-01

    The national conference 'MATERIAUX 2010', which took place in Mahdia (Tunisia), from 4-7 November 2010 was organized by The 'Tunisian Materials Research Society: Tu-MRS' in collaboration with the Materials Physics Laboratory of Sfax 'LPM', Faculty of Sciences, Sfax University and the Research Unit ' Physique, Informatique et Mathématiques ', Faculty of Sciences, Gafsa University The First National Conference on Materials 'MATERIAUX 2006' was organized in Douz (Tunisia) in December 2006. This was followed by 'MATERIAUX 2007' held in Hammamet (Tunisia) in April 2007 and the National Conference 'MATERIAUX 2009' organized jointly with the Second 'Journées Internationales de la Physique des Matériaux et Applications: JIPMA 2009' in Gafsa (Tunisia) from 20-24 December 2009. 'MATERIAUX 2010' is intended to provide an excellent opportunity for National, Maghreb and International researchers to make their own work on materials known to a wider audience and to have discussions with other participants. This conference will also be an opportunity to exchange experiences, create and consolidate cooperation between different research structures in the Maghreb countries and also the countries around the Mediterranean. This conference will equally promote research development, contribution to collaboration between universities and the socio-economical milieu. More than 300 senior researchers, Professors, PhD and Masters students attended this conference from Tunisia, Algeria, Morocco, France, Spain and Canada. Several researchers, engineers and managers from industrial firms also attended. The conference consisted of plenary talks (8), oral contributions (40) and poster presentations (250). The topics of the Conference were: Nano-materials, nano-systems, thin films, surfaces and interfaces, applications Multifunctionnal materials, magnetic materials, dielectric materials, superconducting materials, applications,... Materials for electronics, informatics and communication

  2. Etude theorique des fluctuations structurales dans les composes organiques a dimensionnalite reduite

    NASA Astrophysics Data System (ADS)

    Dumoulin, Benoit

    Les systemes a dimensionnalite reduite constituent maintenant une branche entiere de la physique de la matiere condensee. Cette derniere s'est developpee rapidement au cours des dernieres annees, avec la decouverte des materiaux organiques qui presentent, justement, des proprietes physiques fortement anisotropes. Cette these presente une etude en trois parties de plusieurs composes organiques qui, bien que tres differents du point de vue de leurs compositions chimiques et de leurs proprietes physiques a haute temperature, subissent tous une instabilite structurale a tres basse temperature. De plus, dans chacun des cas, l'instabilite structurale est precedee d'un important regime fluctuatif a partir duquel les proprietes physiques changent de maniere significative. Notre etude suit un ordre chronologique inverse puisque nous nous attardons en premier lieu au cas de composes recemment decouverts: les composes de la famille des (BCPTTF)2X (X = PF6 , AsF6). Ces derniers sont des isolants magnetiques a la temperature ambiante et subissent une instabilite structurale de type spin-Peierls a une temperature appelee TSP. En particulier, nous nous interessons a l'etude des proprietes physiques de ces systemes dans le regime fluctuatif, qui precede cette instabilite. Notre etude theorique nous permet de comprendre en detail comment ces systemes s'approchent de l'instabilite struturale. Dans la seconde partie de cette these, nous etudions le regime fluctuatif (pre-transitionnel) observe experimentalement dans le compose de (TMTTF)2PF6. Ce compose organique, dont la structure s'apparente aux sels de Bechgaard, subit une instabilite de type spin-Peierls a une temperature T SP = 19K. Bien que ce compose possede la particularite d'etre un bon conducteur a la temperature ambiante, il subit une transition de type Mott-Hubbard a une temperature Trho ≈ 220K et devient alors un isolant magnetique, analogue aux composes de la famille des (BCPTTF)2X. Le regime fluctuatif precedant l

  3. Etudes optiques de nouveaux materiaux laser: Des orthosilicates dopes a l'ytterbium: Le yttrium (lutetium,scandium) pentoxide de silicium

    NASA Astrophysics Data System (ADS)

    Denoyer, Aurelie

    La decouverte et l'elaboration de nouveaux materiaux laser solides suscitent beaucoup d'interet parmi la communaute scientifique. En particulier les lasers dans la gamme de frequence du micron debouchent sur beaucoup d'applications, en telecommunication, en medecine, dans le domaine militaire, pour la, decoupe des metaux (lasers de puissance), en optique non lineaire (doublage de frequence, bistabilite optique). Le plus couramment utilise actuellement est le Nd:YAG dans cette famille de laser, mais des remplacants plus performants sont toujours recherches. Les lasers a base d'Yb3+ possedent beaucoup d'avantages compares aux lasers Nd3+ du fait de leur structure electronique simple et de leur deterioration moins rapide. Parmi les matrices cristallines pouvant accueillir l'ytterbium, les orthosilicates Yb:Y 2SiO5, Yb:Lu2SiO5 et Yb:Sc2SiO 5 se positionnent tres bien, du fait de leur bonne conductivite thermique et du fort eclatement de leur champ cristallin necessaire a l'elaboration de lasers quasi-3 niveaux. De plus l'etude fine et systematique des proprietes microscopiques de nouveaux materiaux s'avere toujours tres interessante du point de vue de la recherche fondamentale, c'est ainsi que de nouveaux modeles sont concus (par exemple pour le champ cristallin) ou que de nouvelles proprietes inhabituelles sont decouvertes, menant a de nouvelles applications. Ainsi d'autres materiaux dopes a l'ytterbium sont connus pour leurs proprietes de couplage electron-phonon, de couplage magnetique, d'emission cooperative ou encore de bistabilite optique, mais ces proprietes n'ont encore jamais ete mises en evidence dans Yb:Y 2SiO5, Yb:Lu2SiO5 et Yb:Sc2SiO 5. Ainsi, cette these a pour but l'etude des proprietes optiques et des interactions microscopiques dans Yb:Y2SiO 5, Yb:Lu2SiO5 et Yb:Sc2SiO5. Nous utilisons principalement les techniques d'absorption IR et de spectroscopie Raman pour determiner les excitations du champ cristallin et les modes de vibration dans le materiau

  4. Materiaux composites supraconducteurs

    NASA Astrophysics Data System (ADS)

    Kerjouan, Philippe; Boterel, Florence; Lostec, Jean; Bertot, Jean-Paul; Haussonne, Jean-Marie

    1991-11-01

    The new superconductor materials with a high critical current own a large importance as well in the electronic components or in the electrotechnical devices fields. The deposit of such materials with the thick films technology is to be more and more developped in the years to come. Therefore, we tried to realize such thick films screen printed on alumina, and composed mainly of the YBa2CU3O{7-δ} material. We first realized a composite material glass/YBa2CU3O{7-δ}, by analogy with the classical screen-printed inks where the glass ensures the bonding with the substrate. We thus realized different materials by using some different classes of glass. These materials owned a superconducting transition close to the one of the pure YBa2CU3O{7-δ} material. We made a slurry with the most significant composite materials and binders, and screen-printed them on an alumina substrate preliminary or not coated with a diffusion barrier layer. After firing, we studied the thick films adhesion, the alumina/glass/composite material interfaces, and their superconducting properties. Les nouveaux matériaux supraconducteurs à haute température critique ont potentiellement un rôle important à jouer dans le domaine de l'électronique et de l'électrotechnique. En particulier, le dépôt d'oxydes supraconducteurs sur divers types de substrats est une technologie amenée à se développer. Nous avons donc entrepris une étude dont l'objet est la réalisation de conducteurs sérigraphiés sur alumine et composés essentiellement du matériau YBa2CU3O{7-δ}. Nous avons tout d'abord cherché à réaliser un composite verre/YBa2CU3O{7-δ}, par analogie au principe de réalisation de couches conductrices sérigraphiées, le verre permettant d'obtenir une liaison physico-chimique avec le substrat. Une étude préliminaire a permis de réaliser divers matériaux composites massifs, utilisant différentes familles de verres. Ces matériaux massifs, se présentant sous la forme de barreaux de

  5. Evaluation experimentale et theorique du comportement a la flexion de nouveaux poteaux en materiaux composites

    NASA Astrophysics Data System (ADS)

    Metiche, Slimane

    La demande croissante en poteaux pour les differents reseaux d'electricite et de telecommunications a rendu necessaire l'utilisation de materiaux innovants, qui preservent l'environnement. La majorite des poteaux electriques existants au Canada ainsi qu'a travers le monde, sont fabriques a partir de materiaux traditionnels tel que le bois, le beton ou l'acier. Les motivations des industriels et des chercheurs a penser a d'autres solutions sont diverses, citons entre autre: La limitation en longueur des poteaux en bois ainsi que la vulnerabilite des poteaux fabriques en beton ou en acier aux agressions climatiques. Les nouveaux poteaux en materiaux composites se presentent comme de bons candidats a cet effet, cependant; leur comportement structural n'est pas connu et des etudes theoriques et experimentales approfondies sont necessaires avant leur mise en marche a grande echelle. Un programme de recherche intensif comportant plusieurs projets experimentaux, analytiques et numeriques est en cours a l'Universite de Sherbrooke afin d'evaluer le comportement a court et a long termes de ces nouveaux poteaux en Polymeres Renforces de Fibres (PRF). C'est dans ce contexte que s'inscrit la presente these, et notre recherche vise a evaluer le comportement a la flexion de nouveaux poteaux tubulaires coniques fabriques en materiaux composites par enroulement filamentaire et ce, a travers une etude theorique, ainsi qu'a travers une serie d'essais de flexion en "grandeur reelle" afin de comprendre le comportement structural de ces poteaux, d'optimiser la conception et de proposer une procedure de dimensionnement pour les utilisateurs. Les poteaux en Polymeres Renforces de Fibres (PRF) etudies dans cette these sont fabriques avec une resine epoxyde renforcee de fibres de verre type E. Chaque type poteaux est constitue principalement de trois zones ou les proprietes geometriques (epaisseur, diametre) et les proprietes mecaniques sont differentes d'une zone a l'autre. La difference

  6. Des proprietes de l'etat normal du modele de Hubbard bidimensionnel

    NASA Astrophysics Data System (ADS)

    Lemay, Francois

    Depuis leur decouverte, les etudes experimentales ont demontre que les supra-conducteurs a haute temperature ont une phase normale tres etrange. Les proprietes de ces materiaux ne sont pas bien decrites par la theorie du liquide de Fermi. Le modele de Hubbard bidimensionnel, bien qu'il ne soit pas encore resolu, est toujours considere comme un candidat pour expliquer la physique de ces composes. Dans cet ouvrage, nous mettons en evidence plusieurs proprietes electroniques du modele qui sont incompatibles avec l'existence de quasi-particules. Nous montrons notamment que la susceptibilite des electrons libres sur reseau contient des singularites logarithmiques qui influencent de facon determinante les proprietes de la self-energie a basse frequence. Ces singularites sont responsables de la destruction des quasi-particules. En l'absence de fluctuations antiferromagnetiques, elles sont aussi responsables de l'existence d'un petit pseudogap dans le poids spectral au niveau de Fermi. Les proprietes du modele sont egalement etudiees pour une surface de Fermi similaire a celle des supraconducteurs a haute temperature. Un parallele est etabli entre certaines caracteristiques du modele et celles de ces materiaux.

  7. Qualification sous irradiation du crayon cea: de la conception des composants a l'irradiation d'assemblages en reacteur de puissance

    NASA Astrophysics Data System (ADS)

    Marin, Jean-François; Pillet, Claude; François, Bernard; Morize, Pierre; Petitgrand, Sylvie; Atabek, Rose-Marie; Houdaille, Brigitte

    1982-04-01

    Cet article résume les principaux résultats obtenus au CEA au cours des dix dernières années dans la conception, la qualification et la fabrication des différents éléments originaux constitutifs d'un assemblage de réacteur à eau pressurisée, notamment: l'oxyde UO 2 obtenu par le procédé du Double Cycle Inverse, la gaine en zircaloy 4 recris talllsée, la grille à ressort papillon, la structure à grilles coulissantes. Les etudes et essais hors-pile de comportement thermomécanique du crayon et thermohydraulique des composants de l'assemblage, les irradiations paramétriques de crayons jusqu'à une combustion massique élevée, la validation à partir d'examens aprés irradiation des principaux modèles introduits dans les calculs de conception, enfin l'introduction en réacteur prototype, puis en réacteur de puissance d'assemblages comportant ces différents éléments, constituent les principales étapes de ce développement.

  8. Etude des phenomenes de penetration des especes chimiques dans les revetements cathodiques des cuves d'electrolyse de l'aluminium

    NASA Astrophysics Data System (ADS)

    Brisson, Pierre-Yves

    Cette these decrit l'etude effectuee sur les phenomenes d'insertion du sodium et de penetration du bain electrolytique dans les revetements cathodiques des cuves d'electrolyse de l'aluminium. L'etude fut effectuee a l'aide d'un montage permettant d'effectuer l'electrolyse en laboratoire. Trois types de revetement cathodiques furent etudies : des blocs semi-graphitique, des blocs graphitiques et des blocs graphitises. L'insertion du sodium dans les trois differents types de blocs fut etudiee a l'aide de la spectrometrie des photoelectrons X (XPS). L'analyse a permis de mettre en evidence deux formes de sodium dans l'anthracite et la phase liante des materiaux semi-graphitiques et graphitiques, indiquant qu'une fraction du sodium se retrouve sous forme adsorbee dans les micropores des materiaux alors que l'autre fraction est inseree dans la structure cristalline du carbone. Dans les phases graphitiques (materiaux graphitises et graphitiques), seuls les micropores sont occupes par le sodium Ce resultat explique la tendance observee selon laquelle l'ajout de graphite dans les blocs permet d'abaisser le gonflement sodique. Les mecanismes de penetration du bain dans le reseau poreux des materiaux furent etudies en microscopie electronique et en diffraction des rayons X sur des echantillons apres differents temps d'electrolyses et en variant l'atmosphere (soit sous argon ou sous azote). Ces analyses ont permis d'identifier le mecanisme conduisant a la mouillabilite du bain sur le carbone en fonction de l'atmosphere entourant l'electrolyse. Ainsi, sous azote, la formation de NaCN dans les pores des materiaux par reactions entre le sodium et l'azote permet une mouillabilite accrue du bain alors qu'en absence d'azote (sous argon), le carbure d'aluminium, formes a la surface des pores, joue un role similaire. Dans ce dernier cas, la penetration du bain est moins rapide etant donnee la necessite de toujours amener des especes contenant de l'aluminium en tete du front de

  9. Etude de la resistance en fatigue des materiaux bitumineux

    NASA Astrophysics Data System (ADS)

    Touhara, Radouen

    The goal of this research program is to evaluate and characterize the fatigue behaviour of two GB20 hot mix asphalt made with two different bitumen. One of them is made in laboratory with a straight-run PG58-28 bitumen, while the second mix was made in an asphalt plant with a PG64-28 bitumen. Two characterization tests, in homogeneous conditions, done in traction/compression on cylindrical specimens are used in this study. First, a complex modulus test performed in the linear viscoelasticity (LVE) domain is used to characterize the mixes and second, a fatigue test is done to evaluate the mixes performances. The fatigue tests were done in strain controlled at different amplitude. All fatigue tests were performed at 10Hz, but at different temperatures (10, 20 and 30°C) in order to evaluate the effect of the temperature on the fatigue behaviour of those mixes. In this document, the results are presented, and the analysis of the results as a function of the grade of bitumen, the tests’ temperature and the dispersion of the results is performed. Also, the DGCB method is applied to the fatigue results to calculate the rate of damage per cycle followed by a study of the different failure criteria (Nf) to predict the fatigue life of asphalt mixes. Keywords: bituminous materials, fatigue, complex modulus, Damage.

  10. Incertitude dans les mesures de courant : un obstacle dans la caractérisation des composants en électronique de puissance

    NASA Astrophysics Data System (ADS)

    Farjah, E.; Barbaroux, J.; Perret, R.

    1993-07-01

    The aim of this paper is to clarify the need for the most accurate current measurement applied to the characterization of the power electronic components. The focus is on the behaviour of the normally used high quality high bandwidth current transformers and other sensors to a fast varying high di/dt test current furnished by a new developed test current generator. In this paper after explaining the new strategy of the test generator, different current transformers are tested and characterized and a detailed comparative experimental study is carried out using a non-inductive shunt as the reference. Finally some general remarks and the necessary precautions and different measurement problems are listed and discussed. Le but de cet article est d'essayer de lever les obstacles rencontrés lors des mesures de courant servant à la caractérisation des composants en électronique de puissance. Nous nous sommes penchés sur les différences entre les réponses de quelques capteurs de haute qualité. Après une brève explication du principe d'un générateur de courant de test spécialement conçu pour cette étude, nous comparons les réponses de plusieurs transformateurs de courant par rapport à un shunt aselfique pris pour référence. Enfin nous abordons les différents aspects concernant les précautions qu'il est nécessaire de prendre pour réaliser ce type de mesure.

  11. Recorder Composer

    ERIC Educational Resources Information Center

    Stephenson, Kimberly

    2012-01-01

    The best moments happen when students begin to realize how much power they have and use that power to create. Composing as they master different instrumental stages helps students make composition and performance a natural step in learning. A step-by-step process (rhythm notation, add pitches, copy to a five-line staff, check work, and play) keeps…

  12. Adsorption de gaz sur les materiaux microporeux modelisation, thermodynamique et applications

    NASA Astrophysics Data System (ADS)

    Richard, Marc-Andre

    2009-12-01

    Nos travaux sur l'adsorption de gaz dans les materiaux microporeux s'inscrivent dans le cadre des recherches visant a augmenter l'efficacite du stockage de l'hydrogene a bord des vehicules. Notre objectif etait d'etudier la possibilite d'utiliser l'adsorption afin d'ameliorer l'efficacite de la liquefaction de l'hydrogene des systemes a petite echelle. Nous avons egalement evalue les performances d'un systeme de stockage cryogenique de l'hydrogene base sur la physisorption. Comme nous avons affaire a des plages de temperatures particulierement etendues et a de hautes pressions dans la region supercritique du gaz, nous avons du commencer par travailler sur la modelisation et la thermodynamique de l'adsorption. La representation de la quantite de gaz adsorbee en fonction de la temperature et de la pression par un modele semi-empirique est un outil utile pour determiner la masse de gaz adsorbee dans un systeme mais egalement pour calculer les effets thermiques lies a l'adsorption. Nous avons adapte le modele Dubinin-Astakhov (D-A) pour modeliser des isothermes d'adsorption d'hydrogene, d'azote et de methane sur du charbon actif a haute pression et sur une grande plage de temperatures supercritiques en considerant un volume d'adsorption invariant. Avec cinq parametres de regression (incluant le volume d'adsorption Va), le modele que nous avons developpe permet de tres bien representer des isothermes experimentales d'adsorption d'hydrogene (de 30 a 293 K, jusqu'a 6 MPa), d'azote (de 93 a 298 K, jusqu'a 6 MPa) et de methane (de 243 a 333 K, jusqu'a 9 MPa) sur le charbon actif. Nous avons calcule l'energie interne de la phase adsorbee a partir du modele en nous servant de la thermodynamique des solutions sans negliger le volume d'adsorption. Par la suite, nous avons presente les equations de conservation de la niasse et de l'energie pour un systeme d'adsorption et valide notre demarche en comparant des simulations et des tests d'adsorption et de desorption. En plus de l

  13. Comportement des materiaux cimentaires: Actions des sulfates et de la temperature

    NASA Astrophysics Data System (ADS)

    Barbarulo, Remi

    The research work presented in this Ph.D. thesis is related to the nuclear waste underground repository concept. Concrete could be used in such a repository, and would be subjected to variations of temperature in presence of sulfate, a situation that could induce expansion of concrete. The research was lead in three parts: an experimental study of the possibility of an internal sulfate attack on mortars; an experimental study and modeling of the chemical equilibriums of the CaO-SiO2-Al2O 3-SO-H2O system; and a modeling of the mechanisms of internal and external sulfate attacks, and the effect of temperature. The results show that mortars can develop expansions after a steam-cure during hydration, but also when a long steam-cure is applied to one-year-old mortars, which is a new point. Ettringite precipitation can be considered as responsible for these expansions. The experimental study of the CaO-SiO2-Al2O 3-SO3-H2O system clarified the role of Calcium Silicate Hydrates (C-S-H) on chemical equilibriums of cementitious materials. Sulfate sorption on C-S-H has been studied in detail. The quantity of sulfate bound to the C-S-H mainly depends on the sulfate concentration in solution, on the Ca/Si ratio of the C-S-H and is not significantly influenced by temperature. Aluminium inclusion in the C-S-H seems to be a significant phenomenon. Temperature increases the calcium sulfoaluminate solubilities and thus increases sulfates concentration in solution. A modeling of the chemical system is proposed. Simulations of external sulfate attack (15 mmol/L of Na2SO 4) predict ettringite precipitation at 20 and 85°C. Simulation of internal sulfate attack was performed at a local scale (a hydrated cement grain). An initial inhomogeneity can lead, after a thermal curing at 85°C, to ettringite precipitation in zones originally free from ettringite. This new-formed ettringite could be the origin of the expansions.

  14. Composing and Arranging Careers

    ERIC Educational Resources Information Center

    Schwartz, Elliott; And Others

    1977-01-01

    With the inspiration, the originality, the skill and craftsmanship, the business acumen, the patience, and the luck, it's possible to become a classical composer, pop/rock/country composer, jingle composer, or educational composer. Describes these careers. (Editor/RK)

  15. Contribution a l'etude des mecanismes de l'adhesion de la glace a differents materiaux et application a l'evaluation des materiaux glaciophobes

    NASA Astrophysics Data System (ADS)

    Ghalmi, Zahira

    Several Nordic countries with cold climates like Canada are often subjected to ice storms causing major economic and social losses. Ice or sticky snow adhesion on power network equipment can be a significant issue in transmission and distribution of electrical energy for companies operating in these regions. The costs of such events can be substantial, particularly due to the cessation of economic activities, equipment failures, deicing techniques (active methods), and population safety. Because of such events, power companies have understood the need to develop so-called superhydrophobic and/or icephobic surfaces, which can significantly reduce ice adhesion (passive methods). Several studies have led to the development of a variety of new nanostructured surfaces using various strategies. These studies have led to the design of superhydrophobic surfaces with contact angles greater than 150 and low ice adhesion strength. In order to optimally reduce the ice adhesion strength on different substrates, better understanding of the various mechanisms involved in the icing process is essential. It is in this context and within the framework of Canada's research chair on atmospheric icing of power networks (INGIVRE) that this thesis was carried out, aiming to improve the knowledge of atmospheric icing, and explain the forces involved at the ice/substrate interface. Furthermore, the effect of contact angle, surface roughness and porosity on icing and ice/substrate interface was investigated. This study clearly showed that the electrostatic, van der Waals and hydrogen bond forces are the main contributors to ice adhesion to a surface at the molecular level. The electrostatic energy, based on the principle of image charge, depends on the type of material in contact with the ice, the distance between the ice and the material, and the types of ice surface defects. The van der Waals energy depends on the material type, the thickness of the liquid water layer, and the temperature. For its part, the energy associated with hydrogen bonds depends on the material type, temperature, droplet mass, as well as on the static and sliding contact angles. Among these three forces, the electrostatic energy is the largest. Whereas the hydrogen bond energy is larger than the van der Waals energy. However, the latter is always present as long as ice is in contact with a solid surface. The experimental study showed that ice adhesion strength depends on the surface roughness of the substrate. In the case of metals with a thin natural protective oxide layer, higher roughness leads to higher ice adhesion strength. In other words, polished metallic surfaces exhibit lower ice adhesion strengths. However, in the case of anodized aluminum surfaces coated with PTFE, the roughened needle-like structure resulted in lower ice adhesion. The experimental results showed that PTFE coatings remain resistant to icing/deicing cycles. Even after 15 icing/deicing cycles, surfaces remain hydrophobic with a static contact angle greater than 130°.

  16. My Career: Composer

    ERIC Educational Resources Information Center

    Morganelli, Patrick

    2013-01-01

    In this article, the author talks about his career as a composer and offers some advice for aspiring composers. The author works as a composer in the movie industry, creating music that supports a film's story. Other composers work on television shows, and some do both television and film. The composer uses music to tell the audience what kind of…

  17. Conception axiomatique des joints hybrides a recouvrement simple en materiaux composites

    NASA Astrophysics Data System (ADS)

    Ouellet, Marc

    Minimizing weight is a primary objective in every system design in the aerospace and automotive industry. Therefore, the use of composite materials has become an integral part of the design of mechanical components. However, in composite structure design, their complexity normally makes it impossible to design them as a single part. This leads to the necessity of using joints. Sadly, these joints introduce discontinuities in the stress distribution within the components and are often the sites of stress concentration. Therefore, they may limit the performance of a structure, in addition to increasing the overall mass significantly due to the use of mechanical fasteners such as bolts and rivets. This is why bonded joints are increasingly popular. They are much lighter than bolted or riveted joints and are often more rigid. Unfortunately, it is very difficult to inspect a bonded joint for defects since the presence of cracks in the adhesive cannot be observed with the naked eye. The main objective of this work is to propose a new design methodology for hybrid joints. To accomplish this, it is necessary to establish reliable analysis tools to improve our understanding of the behavior of these joints when subjected to an external force. A better understanding of the interactions between the parameters is also required. To improve our knowledge on the subject, a literature review was conducted. This review was structured as to emphasize on the behavior of hybrid single lap joints when subjected to an external force in tension. Following this literature review, an analysis of the stress distribution within the joint was carried out using a finite element model. The model and the results were compared with those from two papers in order to validate the quality of representation. Subsequently, a modification was made to an existing analytical model in order to add the bolts' preload as a parameter. These two models, namely the finite element model and the analytical model, were then used for a sensitivity study using a design of experiments. To perform this analysis, a kriging model was used to reduce the computing time. Finally, the hybrid single lap joint was analyzed using axiomatic design in order to propose new approach to design these joints. The results of this work can be divided into three parts. First, an analytical model identified in the literature review has been improved to take into account the bolts' preload. The results are satisfactory within the limitations of the original model. It must be pointed out that this model does not consider the non-linear behavior of materials used in the joint, which can lead to poor reliability when highly non-linear materials are used. The sensitivity analysis carried out using the analytical model and the finite element model identified the influence of the parameters on the mechanical performances of the joint. It should be noted that the width of the joint is one of the most important parameter, as well as the thickness of the adherents. The sensitivity analysis also identified the notable effect of the radial clearance of the bolt shank. This parameter should be minimized in order to maximize performances. Finally, the geometry obtained with the axiomatic design and through physical integration reduced the maximum peel stress considerably. The use of washers based on Belleville springs allowed to significantly increase the area affected by the bolts' preload. Therefore, this final geometry should significantly increase the maximum external load that can be supported by the joint and increase its fatigue life. Finally, an improved geometry was proposed using the theory of axiomatic design. The use of chamfers at the ends of the adherents, the addition of modified washers and the use of a stiffer adhesive between the two bolts have significantly reduced the maximum peel stress in the adhesive layer. These changes have also increased the rigidity of the joint. However, analyzes have not demonstrated a decrease in the maximum shear stress inside the adhesive. Therefore, further

  18. Caracterisation des proprietes dielectriques de materiaux composites a base de polyethylene terephtalate recycle

    NASA Astrophysics Data System (ADS)

    Mebarki, Fouzia

    The aim of this study is to examine the possibility of using thermoplastic composite materials for electrical applications such as supports of automotive engine ignition systems. We are particularly interested in composites based on recycled polyethylene terephtalate (PET). Conventional isolations like PET cannot meet the new prescriptive requirements. The introduction of reinforcement materials, such as glass fibers and mica can improve the mechanical characteristics of these materials. However, this enhancement may also reduce electrical properties especially since these composites have to be used under severe thermal and electric stresses. In order to estimate PET composite insulation lifetimes, accelerated aging tests were carried out at temperatures ranging from room temperature to 140°C and at a frequency of 300Hz. Studies at high temperature will help to identify the service temperature of candidate materials. Dielectric breakdown tests have been made on a large number of samples according to the standard of dielectric strength tests of solid insulating ASTM D-149. These tests have to identify the problematic samples and to check solid insulation quality. The different knowledge gained from this analysis was used to predict material performance. This will give the company the possibility to improve existing formulations and subsequently develop a material having electrical and thermal properties suitable for this application.

  19. Application de la technologie des materiaux sol-gel et polymere a l'optique integree

    NASA Astrophysics Data System (ADS)

    Saddiki, Zakaria

    2002-01-01

    With the advancement of optical telecommunication systems, "integrated optics" and "optical interconnect" technology are becoming more and more important. The major components of these two technologies are photonic integrated circuits (PICs), optoelectronic integrated circuits (OEICs), and optoelectronic multichip modules ( OE-MCMs). Optical signals are transmitted through optical waveguides that interconnect such components. The principle of optical transmission in waveguides is the same as that in optical fibres. To implement these technologies, both passive and active optical devices are needed. A wide variety of optical materials has been studied, e.g., glasses, lithium niobate, III-V semiconductors, sol-gel and polymers. In particular, passive optical components have been fabricated using glass optical waveguides by ion-exchange, or by flame hydrolysis deposition and reactive ion etching (FHD and RIE ). When using FHD and RIE, a very high temperatures (up to 1300°C) are needed to consolidate silica. This work reports on the fabrication and characterization of a new photo-patternable hybrid organic-inorganic glass sol-gel and polymer materials for the realisation of integrated optic and opto-electronic devices. They exhibit low losses in the NIR range, especially at the most important wavelengths windows for optical communications (1320 nm and 1550 nm). The sol-gel and polymer process is based on photo polymerization and thermo polymerization effects to create the wave-guide. The single-layer film is at low temperature and deep UV-light is employed to make the wave-guide by means of the well-known photolithography process. Like any photo-imaging process, the UV energy should exceed the threshold energy of chemical bonds in the photoactive component of hybrid glass material to form the expected integrated optic pattern with excellent line width control and vertical sidewalls. To achieve optical wave-guide, a refractive index difference Delta n occurred between the isolated (guiding layer) and the surrounding region (buffer and cladding). Accordingly, the refractive index emerges as a fundamental device performance material parameter and it is investigated using slab wave-guide. (Abstract shortened by UMI.)

  20. Unskilled Writers as Composers.

    ERIC Educational Resources Information Center

    Perl, Sondra

    1979-01-01

    Composition is not a straightforward, linear process; it involves a creative search for meaning that becomes clear only as the writer engages in the composing process. This suggests that teaching not dwell on the correctness of the finished product. (Author/SJL)

  1. Decomposing Composing Conventions.

    ERIC Educational Resources Information Center

    Beers, Terry

    Recent research has invited critiques of the authoritative descriptions of composing found in many rhetoric textbooks. The concept of "convention" may be especially useful in rethinking the teleological basis of these textbook descriptions. Conventions found in composition textbooks need to be unmasked as arbitrary concepts which serve to…

  2. Composing a Research Life

    ERIC Educational Resources Information Center

    Cochran-Smith, Marilyn

    2012-01-01

    In this article about her early career development and the experiences that shaped her life as a scholar and researcher, the author describes the work lives of university-based teacher educators and what it means to compose a research life in this field. This article draws on the author's 30 years as a university-based teacher educator. In it, she…

  3. Les effets des interfaces sur les proprietes magnetiques et de transport des multicouches nickel/iron et cobalt/silver

    NASA Astrophysics Data System (ADS)

    Veres, Teodor

    Cette these est consacree a l'etude de l'evolution structurale des proprietes magnetiques et de transport des multicouches Ni/Fe et nanostructures a base de Co et de l'Ag. Dans une premiere partie, essentiellement bibliographique, nous introduisons quelques concepts de base relies aux proprietes magnetiques et de transport des multicouches metalliques. Ensuite, nous presentons une breve description des methodes d'analyse des resultats. La deuxieme partie est consacree a l'etude des proprietes magnetiques et de transport des multicouches ferromagnetiques/ferromagnetiques Ni/Fe. Nous montrerons qu'une interpretation coherente de ces proprietes necessite la prise en consideration des effets des interfaces. Nous nous attacherons a mettre en evidence, a evaluer et a etudier les effets de ces interfaces ainsi que leur evolution, et ce, suite a des traitements thermiques tel que le depot a temperature elevee et l'irradiation ionique. Les analyses correlees de la structure et de la magnetoresistance nous permettront d'emettre des conclusions sur l'influence des couches tampons entre l'interface et le substrat ainsi qu'entre les couches elles-memes sur le comportement magnetique des couches F/F. La troisieme partie est consacree aux systemes a Magneto-Resistance Geante (MRG) a base de Co et Ag. Nous allons etudier l'evolution de la microstructure suite a l'irradiation avec des ions Si+ ayant une energie de 1 MeV, ainsi que les effets de ces changements sur le comportement magnetique. Cette partie debutera par l'analyse des proprietes d'une multicouche hybride, intermediaire entre les multicouches et les materiaux granulaires. Nous analyserons a l'aide des mesures de diffraction, de relaxation superparamagnetique et de magnetoresistance, les evolutions structurales produites par l'irradiation ionique. Nous etablirons des modeles qui nous aideront a interpreter les resultats pour une serie des multicouches qui couvrent un large eventail de differents comportements magnetiques

  4. Process of timbral composing

    NASA Astrophysics Data System (ADS)

    Withrow, Sam

    In this paper, I discuss the techniques and processes of timbral organization I developed while writing my chamber work, Afterimage. I compare my techniques with illustrative examples by other composers to place my work in historical context. I examine three elements of my composition process. The first is the process of indexing and cataloging basic sonic materials. The second consists of the techniques and mechanics of manipulating and assembling these collections into larger scale phrases, textures, and overall form in a musical work. The third element is the more elusive, and often extra-musical, source of inspiration and motivation. The evocative power of tone color is both immediately evident yet difficult to explain. What is timbre? This question cannot be answered solely in scientific terms; subjective factors affect our perception of it.

  5. Teaching Composing with an Identity as a Teacher-Composer

    ERIC Educational Resources Information Center

    Francis, Jennie

    2012-01-01

    I enjoy composing and feel able to write songs that I like and which feel significant to me. This has not always been the case and the change had nothing to do with my school education or my degree. Composing at secondary school did not move beyond Bach and Handel pastiche. I did not take any composing courses during my degree. What did influence…

  6. Composing the Curriculum: Teacher Identity

    ERIC Educational Resources Information Center

    Lewis, Rebecca

    2012-01-01

    What is composing and how is it valued? What does a good education in composing look like; what constraints hinder it and is it possible to overcome such constraints? Can composing be a personal, creative and valuable activity for the school student? What role does the teacher play in all of this? These are questions that I discuss in this…

  7. How Composers Compose: In Search of the Questions

    ERIC Educational Resources Information Center

    Andrews, Bernard W.

    2004-01-01

    The Genesis Project is a multi-phase research project designed for the purpose of developing an in-depth understanding of the nature of musical creativity by investigating how composers compose. In this first phase of the project, an understanding of the four dimensions of musical creativity: (1) the "person", (2) the compositional "process", (3)…

  8. Recuperation d'energie issue des deformations de structures aeronautiques a l'aide de materiaux piezoelectriques

    NASA Astrophysics Data System (ADS)

    Debeaux, Sebastien

    Aerospace structural maintenance (fuselage, wings) is a major component of operational costs which requires aircraft to be grounded and some of its parts to be dismantled in order to proceed to inspection. In order to allow in situ monitoring, Structural Health Monitoring (SHM) has been proposed where sensors and actuators are integrated on the structure. To avoid extensive wiring of the nodes, wireless sensors and actuators are attractive but should be self powered to fully benefit from them. One idea is to convert the mechanical energy (vibrations) available all over an aircraft into electricity using piezoelectric materials. This work investigates the potential of strain-based energy harvesters (as opposed to inertial harvesters) to supply wireless nodes on typical aircraft structures. A simple model is used to describe typical dynamic behavior of aircraft components: a beam representing the whole wing subjected to aerodynamic loading and a plate representing a fuselage panel subjected to pressure fields (jet noise and turbulent boundary layer). Various configurations of piezoelectric materials are tested such as bulk PZT, PZT fiber composite and Polyvinylidene Fluoride (PVDF) in order to evaluate the influence of their characteristics (size, polarization, electrodes' shape, capacitance...) on the harvested power. The results show that for a typical aerospace excitation of the beam (10 Hz and 56 μdef), the energy produced is up to 40 mJ with bulk PZT for a 7 minutes loading time. From the literature, this appears sufficient for RF transmission (25 μJ). For other excitation sources (for instance jet noise), the energy produced is up to only 1 mJ with bulk PZT for a 25 minutes loading time. The drawback is that we should wait for several seconds in order to charge the harvester's battery. And, considering that many other components than the RF transceiver will require energy in the meantime, the time laps between two' measures could increase to several minutes. Therefore, strain-based energy harvester could be used for supplying wireless sensor nodes but they would not allow real time measurement. However this approach is a simple and convenient way to scavenge energy compared to other kinds of harvesters (inertial, solar...) since it amounts to bonding a piezoelectric material on a flexible surface. Some design advices are eventually proposed for this kind of harvesters. They could be used for designing a harvester able to produce desired power from a known excitation. Keywords: Power harvesting, piezoelectric, piezoelectric fiber composite, vibration energy, structural health monitoring.

  9. Etude de la performance de piles a combustible microbiennes et l'effet des materiaux d'electrodes

    NASA Astrophysics Data System (ADS)

    Martin, Edith

    Recent climate change has brought a whole new dimension to the energy field since now we must change our primary source, fossil fuels. The microbial fuel cell (MFC) technology emerged as a result of recent efforts in the development of alternative sources of energy. This project aims to improve the performance maximization of such celsl. It is assumed that the microbial fuel cells' functioning is influenced by the operation conditions as well as the biofilm development and other limitations. It is also appropriate to suppose that the electrode materials also have consequences on either the microorganisms' activity or the electrochemical reaction reactivity. Thus, various operating conditions and configurations are tested to identify the specific effects of these changes on cell performance. Also, the development of the biofilm is extensively studied under various conditions to improve the electrons transfer between the active biofilm and the anode. These experiments and analyses permitted to identify various effects that can improve the microbial fuel cell performance. Thus, the influence of organic load (of glucose and acetate), pH and operating temperature of the fuel cell has been shown and optimal values were determined, leading to a significant increase in the anodic biofilm activity and a decrease of the methanogens activity, the latter reducing the coulombic efficiency by diverting a non-negligible substrate amount for their benefit. Hence, organic loading of 2 to 4 g L-1 day-1, pH between 6,25 and 6,5 as well as high cathode temperature (62 °C) but moderate anode temperature (30 °C) caused a maximum power generation increase to 19,2 W m -3. During the experiments with acetate as substrate, distance between electrodes and fuel cell volume have been reduced, leading to a power density of 92,4 W m-3. All these observations are the subject of the first article presented in this thesis. Since the microbial fuel cell power generation depends on the number of anode-reducing microorganisms populating the biofilm, this relationship was deepened in the second manuscript. This article, which intended to monitor the biofilm development, highlights the influence of external load changing rate during the active biofilm growth. Thus, when the external load is adjusted rapidly to approach the cell internal resistance, electrons exchange is enhanced as well as the proliferation of microorganisms responsible of these electrons generation. By promoting faster anode-reducing microorganisms growth, other species are somewhat disadvantaged and substrate consumption is primarily involved in the electricity production rather than any other unwanted products (eg.: methane). This article also demonstrates the influence of the biofilm development level on the diffusion limitation of the anodic reaction, a limitation that becomes more pronounced as the biofilm grows. The third article clarifies the diffusion limitation of the charge transfer at the anode. Therefore, the organic load variation of acetate in microbial fuel cells with carbon felt (3D) and carbon paper (2D) anodes as well as the electrolyte conductivity decrease has targeted protons diffusion out of the biofilm as the current generation limitation. In addition, a secondary electrochemical reaction has been identified at the anode, creating an electrode resistance increase and thereby a slight power output decrease. Finally, multiple electrochemical analyses helped to establish with certainty that the electron transfer mechanism carried out by anode-reducing microorganisms is by direct contact with the anode via microorganisms themselves or the conductive biofilm matrix, cytochromes being responsible for the electrons transport in both cases. The last manuscript deals with new cathode materials (carbon, Mn 2O3 and Fe2O3) evaluation in comparison to a platinum cathode. These materials were chosen for their potential to stimulate the proliferation of microorganisms capable of influencing cathode activity in order to obtain a biocathode; however, this phenomenon has not been verified. (Abstract shortened by UMI.)

  10. Tropes of the Composing Process.

    ERIC Educational Resources Information Center

    Arrington, Phillip K.

    1986-01-01

    Offers a montage of the most important revisions of the four master tropes--metaphor, metonymy, synecdoche, and irony--for the composing process itself. Discusses the capacity of tropes to prefigure ideological stances toward language and writing. (EL)

  11. Guidelines for Coaching Student Composers.

    ERIC Educational Resources Information Center

    Wilson, Dana

    2001-01-01

    Focuses on teaching students how to compose music. Addresses issues, such as how to get the students started and types of questions to ask students about their compositions. Discusses the musical elements involved in composition, such as melody, harmony, rhythm and meter, timbre, texture, and formal design. (CMK)

  12. Multicolor well-composed pictures

    NASA Astrophysics Data System (ADS)

    Latecki, Longin J.

    1995-01-01

    As was noted early in the history of computer vision, using the same adjacency relation for the entire digital picture leads to so-called `paradoxes' related to the Jordan Curve Theorem. The most popular idea to avoid these paradoxes in binary images was using different adjacency relations for the foreground and the background: 8-adjacency for black points and 4-adjacency for white points, or vice versa. This idea cannot be extended in a straightforward way to multicolor pictures. In this paper a solution is presented which guarantees avoidance of the connectivity paradoxes related to the Jordan Curve Theorem for all multicolor pictures. Only one connectedness relation is used for the entire digital picture, i.e., for every component of every color. The idea is not to allow a certain `critical configuration' which can be detected locally to occur in digital pictures; such pictures are called `well-composed.' Well-composed pictures have very nice topological properties. For example, the Jordan Curve Theorem holds and the Euler characteristic is locally computable. This implies that properties of algorithms used in computer vision can be stated and proved in a clear way, and that the algorithms themselves become simpler and faster. Moreover, if a digitization process is guaranteed to preserve topology, then the obtained digital pictures must be well-composed.

  13. De la caracterisation des materiaux et simulation du procede a l'optimisation de la fabrication des composites par injection sur renfort

    NASA Astrophysics Data System (ADS)

    Ruiz, Eduardo

    The Liquid Composite Molding techniques (LCM) have become widely used composite manufacturing methods for medium to small production volumes. The objectives of this thesis consist of developing characteristic equations that describe the thermo-mechanical behaviour and phase changes of thermosetting matrix composites, create and implement new numerical models for process simulation and finally, propose a new and comprehensive optimization methodology based on genetic algorithms for the curing and cooling of LCM parts. In these processes, the fibrous reinforcement is progressively saturated by the liquid resin. Once the mold cavity is filled, the thermosetting resin polymerizes and solidifies. From the point of view of the numerical simulation, the process can be divided into three principal stages: (1) filling, (2) curing and (3) cooling and demolding. The material characterisation, numerical simulation and optimization of these three stages are included in the scope of works of this thesis. The first part of this study concerns the characterization of the cure kinetics and the viscoelastic behaviour of a glass/polyester composite. A semi-empirical model was developed to take into account the effects of inhibitor decomposition and glass transition on cure kinetics. Two models are proposed to describe the chemical and thermal effects on the mechanical properties of the composite. The first one is a thermo-chemical elastic non-linear model that considers total matrix relaxation in the rubbery state above the glass transition temperature. The second one is a viscoelastic model based on the stress relaxation and the time/temperature superposition principle. A one-dimensional solution of the heat equation coupled with stress analysis has been developed to simulate thermal, chemical and mechanical effects during cure. The calculation of residual stresses and the elastic model have been experimentally verified by molding thin composite plates. A study has been carried out on the evolution of internal stresses during the curing and cooling of thick parts. The optimization of the pre-heating, curing and cooling stages in the manufacturing of composite parts by LCM is finally treated. This comprehensive approach incorporates several objectives in the same optimization procedure: minimization of cycle time, improvement of mechanical properties and reduction of laminate residual stresses. An evolutionary algorithm based on genetic algorithms, the code called LeCoq (Logical Evolutionary Curing Optimization and Quenching), has been developed to optimize the mold temperature transient profile. Finally, the curing of a thick composite part has been optimized with this algorithm. (Abstract shortened by UMI.)

  14. Organists and organ music composers.

    PubMed

    Foerch, Christian; Hennerici, Michael G

    2015-01-01

    Clinical case reports of patients with exceptional musical talent and education provide clues as to how the brain processes musical ability and aptitude. In this chapter, selected examples from famous and unknown organ players/composers are presented to demonstrate the complexity of modified musical performances as well as the capacities of the brain to preserve artistic abilities: both authors are active organists and academic neurologists with strong clinical experience, practice, and knowledge about the challenges to play such an outstanding instrument and share their interest to explore potentially instrument-related phenomena of brain modulation in specific transient or permanent impairments. We concentrate on the sites of lesions, suggested pathophysiology, separate positive (e.g., seizures, visual or auditory hallucinations, or synesthesia [an involuntary perception produced by stimulation of another sense]) and negative phenomena (e.g., amusia, aphasia, neglect, or sensory-motor deficits) and particularly address aspects of recent concepts of temporary and permanent network disorders. PMID:25684298

  15. Etude des effets du martelage repetitif sur les contraintes residuelles

    NASA Astrophysics Data System (ADS)

    Hacini, Lyes

    L'assemblage par soudage peut engendrer des contraintes residuelles. Ces contraintes provoquent des fissurations prematurees et un raccourcissement de la duree de vie des composants. Dans ce contexte, le martelage robotise est utilise pour relaxer ces contraintes residuelles. Trois volets sont presentes: le premier est l'evaluation des effets des impacts unitaires repetes sur le champ de contraintes developpe dans des plaques d'acier inoxydable austenitique 304L vierges ou contenant des contraintes residuelles initiales. Dans la deuxieme partie de ce projet, le martelage est applique grace au robot SCOMPI. Les contraintes residuelles induites et relaxees par martelage sont ensuite mesurees par la methode des contours, qui a ete adaptee a cet effet. Dans la troisieme partie, le martelage est modelise par la methode des elements finis. Un modele axisymetrique developpe grace au logiciel ANSYS permet de simuler des impacts repetes d'un marteau elastique sur une plaque ayant un comportement elastoplastique.

  16. Nurturing the Careers of Australia's Future Composers

    ERIC Educational Resources Information Center

    Watson, Amanda; Forrest, David

    2008-01-01

    In 1994, the Australian Society for Music Education (ASME) initiated two related projects supporting and acknowledging composition in schools and offering the opportunity for secondary school-aged students to work with prominent Australian composers. These were the Young Composers' Project and the Composer-in-Residence Project. Both projects were…

  17. Composers and Children: A Future Creative Force?

    ERIC Educational Resources Information Center

    Colgrass, Michael

    2004-01-01

    In this article, a professional composer shares his experiences writing music for a middle school band. Michael Colgrass was commissioned, along with fourteen other composers, by the American Composers Forum BandQuest project to write a short piece for eighth-grade band. They were asked to pay a couple of visits to a nearby school to work with…

  18. Analyse de L'ancrage des Vortex Intergrains pour le Yttrium BARYUM(2) CUIVRE(3) OXYGENE(7) Polycristallin

    NASA Astrophysics Data System (ADS)

    Fournier, Patrick

    Le Modele de l'Etat Critique Generalise (MECG) est utilise pour decrire les proprietes magnetiques et de transport du YBa_2Cu_3O _7 polycristallin. Ce modele empirique permet de relier la densite de courant critique a la densite de lignes de flux penetrant dans la region intergrain. Deux techniques de mesures sont utilisees pour caracteriser nos materiaux. La premiere consiste a mesurer le champ au centre d'un cylindre creux en fonction du champ magnetique applique pour des temperatures comprises entre 20 et 85K. En variant l'epaisseur de la paroi du cylindre creux, il est possible de suivre l'evolution des cycles d'hysteresis et de determiner des champs caracteristiques qui varient en fonction de cette dimension. En utilisant un lissage des resultats experimentaux, nous determinons J _{co}, H_ {o} et n, les parametres du MECG. La forme des cylindres, avec une longueur comparable au diametre externe, entrai ne la presence d'un champ demagnetisant qui peut etre inclus dans le modele theorique. Ceci nous permet d'evaluer la fraction du volume ecrante, f _{g}, ainsi que le facteur demagnetisant N. Nous trouvons que J_{ co}, H_{o} et f_{g} dependent de la temperature, tandis que n et N (pour une epaisseur de paroi fixe) n'en dependent pas. La deuxieme technique consiste a mesurer le courant critique de lames minces en fonction du champ applique pour differentes temperatures. Nous utilisons un montage que nous avons developpe permettant d'effectuer ces mesures en contact direct avec le liquide refrigerant, i.e. dans l'azote liquide. Nous varions la temperature du liquide en variant la pression du gaz au-dessus du bain d'azote. Cette methode nous permet de balayer des temperatures entre 65K et la temperature critique du materiau ({~ }92K). Nous effectuons le lissage des courbes de courant critique en fonction du champ applique encore a l'aide du MECG, pour a nouveau obtenir ses parametres. Pour trois echantillons avec des traitements thermiques differents, les parametres

  19. Modelisation de materiaux composites adaptatifs munis d'actionneurs en alliage a memoire de forme

    NASA Astrophysics Data System (ADS)

    Simoneau, Charles

    Technological development of structures having the capabilities to adapt themselves to different operating conditions is increasing in many areas of research such as aerospace. In fact, numerous works are now oriented toward the design of adaptive aircraft wings where the goal is to enhance the aerodynamic properties of the wing. Following this approach, the work realised in the framework of this master thesis presents the steps leading to the creation of a numerical model that can be used to predict the behavior of an adaptive panel, and therefore, eventually of an adaptive aircraft wing. Foremost, the adaptive panel of this project has been designed from a carbon-epoxy composite, acting as host structure, where shape memory alloy (SMA) wires, acting as actuators, have been inserted in it. SMA actuators have also been embedded asymmetrically along the direction of the panel thickness in order to generate a bending moment when the SMA wires are activated. To achieve the modeling of such structure it has been firstly shown that a numerical model composed of only solid finite elements could be used to represent the panel. However, a second numerical model composed of shell, beam and link finite elements showed that identical results can be obtained with much less nodes (the first model was composed of more than 300 000 nodes compared with 1 000 nodes for the second). The combination of shell-beam-link elements has then been chosen. Secondly, a constitutive relation had to be used for modeling the particular behavior of SMA. For the present work, a uniaxial version of the Likhachev's model is used. Due to its fairly straightforward mathematical formulation, this material law is able to model the main functional properties of SMA including the two-way shape memory effect (TWSME) at zero stress obtained after a thermomechanical education treatment. The last step was to compare the results of the numerical simulations with those obtained with a prototype where 19

  20. The composing process in technical communication

    NASA Technical Reports Server (NTRS)

    Masse, R. E.

    1981-01-01

    The theory and application of the composing process in technical communications is addressed. The composing process of engineers, some implications for composing research for the teaching and research of technical communication, and an interpretation of the processes as creative experience are also discussed. Two areas of technical communications summarized concern: the rhetorical features of technical communications, and the theoretical background for a process-based view, a problem-solving approach to technical writing.

  1. The Composing Processes of Unskilled College Writers.

    ERIC Educational Resources Information Center

    Perl, Sondra

    The findings from a study of five students undertaken to determine how unskilled college writers compose, whether their writing processes can be analyzed in a systematic manner, and what an increased understanding of those processes suggests about the nature of composing and about the manner in which writing is taught are presented in this paper.…

  2. A Virtual Composer in Every Classroom

    ERIC Educational Resources Information Center

    Hoffman, Adria R.; Carter, Bruce A.

    2013-01-01

    Previous generations applauded grant-funded programs that brought living composers into the lives of K-12 music students. The current economic climate, however, limits opportunities similar to those enjoyed in the past. We designed a virtual composer-in-residence experience that uses technology to overcome the barriers of funding limitations and…

  3. America's Women Composers: Up from the Footnotes.

    ERIC Educational Resources Information Center

    Pool, Jeannie G.

    1979-01-01

    This article presents an overview on women composers in the United States from the eighteenth century to the present. It also lists women's musical organizations, selected references on women in music, and available recordings of works by American women composers. (SJL)

  4. Films Composed Of Diamond And Diamondlike Carbon

    NASA Technical Reports Server (NTRS)

    Shing, Yuh-Han

    1995-01-01

    Proposed films composed of diamond and diamondlike carbon useful as wear-resistant and self-lubricating protective and tribological coats at extreme temperatures and in corrosive and oxidizing environments. Films have wide variety of industrial applications.

  5. Evaluation de l'effet de la temperature de cure sur le comportement des materiaux bitumineux de type mr-5 traites a la mousse de bitume

    NASA Astrophysics Data System (ADS)

    Cardenas, Jose Alberto

    Cold recycling mixes and cold mixes with RAP are used in Quebec since 1991. However, this practice is not recommended at temperatures below 10 ° C. Very little research on this subject and the effects of low temperatures on the behavior of early mixes are being done. The present study compares the behavior of a MR-5 mix under different cure temperature, 0 ° C, 5 ° C, 10 ° C, and 23 ° C as the reference temperature. The cold curing conditions are explained in details. The research is based on two main aspects: the effect of curing temperature on the cold recycling materials with foamed asphalt and the comparison between two methods of testing the mechanical properties, there are the Marshall stability and the Indirect Tensile Strenght ITS. The study is divided into three stages. The first stage is the optimization of the foam properties and the mix design of test. The second stage is to prepare the specimens of MR-5 MB and the storage on the predefined cure conditions. Finally, the third stage consists of mechanical strength testing of briquettes at the curing time appointed. Meanwhile, at each stage, we evaluate the associated parameters, which are little known and highly useful in road construction. Firstly, we assess the foam index and the surface of contraction, which is used for formulating and optimization of the foam bitumen mixes. Secondly, we evaluate the index of fracture (IF) and the ductility index (ID) associated with the mechanical strength. At the end of the project, we compare the resistance of the MR-5 foamed bitumen used in this research with the MR-5 bitumen emulsion. The latter is more used in the road industry in Quebec and serves as a reference for the comparison. Both tests show that there is an increase in the resistance of the materials with time, even at temperature below 10 ° C. We notice that the percentage of increase in the resistance of the materials is significantly different in both tests. However, the ITS is highly effective in cold mixes characterization and gives more details on the behavior of the MR-5 materials in different temperature.

  6. Optimisation structurale de dalles de chaussees en beton jointees avec des goujons en materiaux composites en Polymeres Renforces de Fibres de Verre (PRFV)

    NASA Astrophysics Data System (ADS)

    Bricola, Julien

    In Quebec, the majority of the road network was built in the 60's - 70's and show obvious signs of ageing. Moreover, the increase of road traffic and the rigorous weather conditions, render the maintenance and the exploitation of roads in this Northern American part quite difficult. Indeed, these environmental conditions cause severe damages for roads, especially in winter. The degradation factor of the jointed rigid pavement is intensified by the highway salt. So, the phenomena of deteriorations appears mainly by the corrosion of the steel at the joints (structural elements) guaranteeing the durability of roads. The jointed rigid pavements or "short jointed pavements" are still mainly sized with steel dowels placed at the lining of joints. One of the main functions of these structures is to control the formation of cracking due to the thermal and environmental conditions. In order to reduce these , disorders, the Ministry of Transport of Quebec (MTQ) turned towards new techniques and innovative materials to ensure the longevity of roads. With the rapid evolution of specific methods and knowledge in roads design, joined with technologies and new products, the MTQ emphasizes the research and development. That way, advanced techniques and diverse technologies in the Quebecois context are settled. As a matter of fact, one of the axes of these development researches concerns the composite materials which have recently been given good results in the civil engineering area. That is why Glass Fibre-Reinforced Polymer (GFRP) dowels bars appear as a solution to the steel corrosion. In fact, they provide better durability with lower costs: the increase of service life as well as the decrease of maintenance persons and traffics impac. Thus, this project proposes an optimization of structural design of GFRP dowels for transverse jointed highway pavement slabs, also keeping in mind their use in new projects. The GFRP dowels which are given in this essay are made by the Pultrall Inc. Company from Thetford Mines (Quebec, Canada). The resin used for the polymer materials is only vinylester resin and the dowels have diameters going from 28.6 mm to 34.9 mm. Finally, only a stiff base is used for the road, its particularity is the modulus of subgrade reaction. Keywords: concrete pavement, dowelled slab, jointed concrete pavement, GFRP dowels, optimization, structural, design .

  7. Interdiffusion de puits quantiques controlee par irradiation laser excimere pour l'integration de composants photoniques

    NASA Astrophysics Data System (ADS)

    Genest, Jonathan

    L'integration de composants discrets sur un systeme unique, tel une puce electronique, augmente les performances totales du systeme, fait apparaitre de nouvelles fonctionnalites et diminue les couts associes a la fabrication des dispositifs. Ces ameliorations, appliquees au secteur de la microelectronique, sont grandement responsables des avancements importants qu'ont connus les technologies de l'information et des communications au cours des dernieres annees. Puisque la fabrication de circuits photoniques integres necessite l'integration de structures ayant des bandes interdites differentes a partir d'une meme puce semiconductrice, leur niveau d'integration est bien inferieur que celui atteint pour un microprocesseur standard. Parmi les techniques ayant le potentiel de fabriquer des circuits photoniques integres monolithiquement, l'interdiffusion de puits quantique post-expitaxial controlee spatialement augmente la bande interdite d'une heterostructure semiconductrice a l'interieur de regions definies. Le processus d'interdiffusion, active thermiquement, est accelere par la diffusion d'impuretes et de defauts ponctuels tels que les lacunes et les interstitiels. L'hypothese de depart de mes travaux de doctorat suppose que la radiation laser ultra-violette module la diffusion et la generation de defauts ponctuels dans les heterostructures reposant sur les technologies a base de GaAs et d'InP et, consequemment, controle spatialement l'interdiffusion de puits quantiques. Nous avons demontre que lorsque appliquee sur des heterostructures a base de GaAs, l'irradiation laser excimere l'interdiffusion en favorisant la croissance d'un stresseur de surface qui empeche la diffusion des defauts ponctuels vers les puits quantiques. Nous avons souligne l'influence de la vapeur d'eau physisorbee sur la croissance du stresseur et avons determine la resolution spatiale de la technique. Dans les heterostructures basees sur les technologies InP, meme sous le seuil d'ablation, l

  8. Music and emotion—a composer's perspective

    PubMed Central

    Douek, Joel

    2013-01-01

    This article takes an experiential and anecdotal look at the daily lives and work of film composers as creators of music. It endeavors to work backwards from what practitioners of the art and craft of music do instinctively or unconsciously, and try to shine a light on it as a conscious process. It examines the role of the film composer in his task to convey an often complex set of emotions, and communicate with an immediacy and universality that often sit outside of common language. Through the experiences of the author, as well as interviews with composer colleagues, this explores both concrete and abstract ways in which music can bring meaning and magic to words and images, and as an underscore to our daily lives. PMID:24348344

  9. Rectenna composed of a circular microstrip antenna

    SciTech Connect

    Itoh, K.; Ohgane, T.; Ogawa, Y.

    1986-01-01

    One of the big problems in the SPS system is reradiation of the harmonic waves generated by the rectifying diode. The authors proposed the use of a circular microstrip antenna (CMSA), since the CMSA has no higher resonance-harmonic of integer multiple of the dominant resonance frequency. However, characteristics of a large rectenna array of CMSA's have not been clarified. This paper is concerned with the absorption efficiency of the rectenna composed of the CMSA. The efficiency is estimated explicitly using an infinite array model. The results show that the absorption efficiency of the infinite rectenna array composed of the CMSA is 100%. Also, this paper considers the effect of the losses of the composed of the CMSA is 100%. Also, this paper considers the effect of the losses of the CMSA. 4 references, 4 figures.

  10. Des Moines.

    ERIC Educational Resources Information Center

    Gore, Deborah, Ed.

    1988-01-01

    This document, intended for elementary students, contains articles and activities designed to acquaint young people with the history of Des Moines, Iowa. The articles are short, and new or difficult words are highlighted and defined for young readers. "The Raccoon River Indian Agency" discusses the archeological exploration of the indian…

  11. Solar cells composed of semiconductive materials

    SciTech Connect

    Hezel, R.

    1981-03-03

    A solar cell is composed of a semiconductive material having an active zone in which charge carriers are produced by photons which strike and penetrate into the solar cell. The cell is comprised of a semiconductive body having an electrically insulating laminate with metal contacts therein positioned on the semiconductor body in the active zone thereof. The insulating laminate is composed of a double layer of insulating material, with the layer in direct contact with the semiconductive surface being composed of SiO2 which is either natural or is produced at temperatures below 800/sup 0/ C. And the layer superimposed above the SiO2 layer being composed of a different insulating material, such as plasma-produced Si3N4. In certain embodiments of the invention, a whole-area pn-junction is provided parallel to the semiconductive surface. The solar cells of the invention exhibit a higher degree of efficiency due to a higher fixed interface charged density, and low surface recombination velocity, an increased UV sensitivity, improved surface protection and passivation and improved anti-reflection characteristics relative to prior art solar cell devices.

  12. Take a Change with Aleatory Composing.

    ERIC Educational Resources Information Center

    Stambaugh, Laura

    2003-01-01

    Discusses how teachers can incorporate musical composition into their classrooms by teaching students about aleatory, or chance, music. Provides a definition of aleatory music and provides various composing techniques, focusing on aleatory music. Includes lesson plans using aleatory music, such as the "Mozart Model" for grades 4-12. (CMK)

  13. The Composer in the Liberal Arts College

    ERIC Educational Resources Information Center

    Schwartz, Elliott

    2011-01-01

    This essay explores the role of music composition within the curriculum of a typical small liberal arts college and the faculty composer's role(s) in facilitating the study of composition. The relationship between composition and campus performance is discussed, particularly in light of the increased emphasis on performance in formerly all-male…

  14. Composing for Digital Publication: Rhetoric, Design, Code

    ERIC Educational Resources Information Center

    Eyman, Douglas; Ball, Cheryl E.

    2014-01-01

    The authors discuss the state of digital publication with the claim that, at this historical moment, nearly all composition is digital composition. But, as a field, composition studies has not yet made that shift completely explicit in the discussions of composing processes and writing pedagogies. A deeper engagement with this very rapid shift in…

  15. Mathematical Approaches to the Composing Process.

    ERIC Educational Resources Information Center

    Hall, Dennis R.

    Rhetoric and mathematics have much in common that can help explain the composing process. Common elements of rhetoric and mathematics important to the teaching of writing are (1) relationships between syntax and semantics, (2) practices of representation, and (3) focus on problem solving. Recent emphasis on "repair processes" in mathematics is…

  16. The Composer's Blueprint: A Teacher's Guide.

    ERIC Educational Resources Information Center

    Trzcinski, Louis C.; Nelhybel, Vaclav

    This teacher's guide is designed to accompany two 15-minute color television programs dealing with the creative process involved in conceiving a composition. The programs are appropriate for junior high school string students and instrumental students in string methods courses at teacher training institutions. In the program, the composer explains…

  17. Prospects for composability of models and simulations

    NASA Astrophysics Data System (ADS)

    Davis, Paul K.; Anderson, Robert B.

    2004-08-01

    This paper is the summary of a recent RAND study done at the request of the U.S. Defense Modeling and Simulation Office (DMSO). Commissioned in recognition that the last decade's efforts by DoD to achieve model "composability" have had only limited success (e.g., HLA-mediated exercises), and that fundamental problems remain, the study surveyed the underlying problems that make composability difficult. It then went on to recommend a series of improvement measures for DMSO and other DoD offices to consider. One strong recommendation was that DoD back away from an earlier tendency toward overselling composability, moving instead to a more particularized approach in which composability is sought within domains where it makes most sense substantively. Another recommendation was that DoD needs to recognize the shortcomings of standard software-engineering paradigms when dealing with "models" rather than pure software. Beyond this, the study had concrete recommendations dealing with science and technology, the base of human capital, management, and infrastructure. Many recommendations involved the need to align more closely with cutting edge technology and emerging standards in the private sector.

  18. Is the Higgs boson composed of neutrinos?

    DOE PAGESBeta

    Krog, Jens; Hill, Christopher T.

    2015-11-09

    We show that conventional Higgs compositeness conditions can be achieved by the running of large Higgs-Yukawa couplings involving right-handed neutrinos that become active at ~1013–1014 GeV. Together with a somewhat enhanced quartic coupling arising by a Higgs portal interaction to a dark matter sector, we can obtain a Higgs boson composed of neutrinos. Furthermore, this is a “next-to-minimal” dynamical electroweak symmetry breaking scheme.

  19. Is the Higgs boson composed of neutrinos?

    SciTech Connect

    Krog, Jens; Hill, Christopher T.

    2015-11-09

    We show that conventional Higgs compositeness conditions can be achieved by the running of large Higgs-Yukawa couplings involving right-handed neutrinos that become active at ~1013–1014 GeV. Together with a somewhat enhanced quartic coupling arising by a Higgs portal interaction to a dark matter sector, we can obtain a Higgs boson composed of neutrinos. Furthermore, this is a “next-to-minimal” dynamical electroweak symmetry breaking scheme.

  20. Alexia without agraphia in a composer.

    PubMed

    Judd, T; Gardner, H; Geschwind, N

    1983-06-01

    A 77-year-old composer had a left occipital lobe haemorrhagic infarct giving a severe reading disturbance with well-preserved writing and without appreciable aphasia. He continued to read music and to compose. His text- and music-reading performance under different conditions suggests that this unusual dissociation was primarily due to four factors. (1) He was unusually talented musically and inferred a great deal about the music he was reading. (2) The symbols of staff music notation are more visually distinctive than the symbols of phonetic language writing systems. (3) In staff music notation, pitch is represented ordinally, and other symbols are also distinguishable by their relative positions and sizes. (4) Music notation can be usefully read by interpreting it acoustically, kinaesthetically or in terms of formal musical concepts; in contrast to written language, it need not be interpreted referentially or in terms of auditory-verbal images. His disorder fits the classic visual-verbal disconnection account of alexia without agraphia and the contemporary view that music involves a family of related but distinct skills probably involving many brain areas in both hemispheres, although different cortical areas make characteristic contributions to different musical behaviours. PMID:6850277

  1. [Mental disease in two classical music composers].

    PubMed

    Rempelakos, L; Poulakou-Rebelakou, E; Ploumpidis, D

    2012-01-01

    A study οn two neglected classical music composers suffering a not syphilitic mental disease, is attempted here, syphilis of the central nervous system being frequent in that time. A brief overview on the psychiatric ailments of many great composers reveals suicide attempts and more or less severe depression following external events. The issue of a possible relationship between mental disease and (musical) creativity can be discussed, as mood swings and a certain tendency to melancholia are frequent features of a talented brain (a fact that can also be detected in their works). The first case presented here is Hans Rott from Austria, the beloved student of Anton Bruckner, who was considered to be at least equal to his famous classmate Gustav Mahler. The great expectations of his teacher and his friends suddenly came to an end, when he suffered a crisis of schizophrenia and was hospitalized in an insane asylum in Lower Austria. The tragic psychiatric adventure of the young musician lasted almost four years. He was diagnosed as a case of "hallucinatory insanity" and "persecution mania" by the medical staff, before dying of tuberculosis, aged only 26, and having completed only one symphony and several smaller works. His name came again on surface only a century after his death, when in 1989 his Symphony in E Major was discovered and premiered with great success, permitting to its creator a posthumous recognition, among Bruckner and Mahler. The second case of mental illness is that of the Armenian Komitas Vardapet. He was an orphan who grew up in theological schools and became a monk and later a priest, though he spent some years in Berlin in order to develop his musical skills. He is considered to be an authority of Armenian ecclesiastic music, introducing polyphony in the Armenian Church's music and collecting numerous traditional songs from all parts of Armenia. In 1915, during the Armenian genocide he was deported, tortured but finally saved, due to interventions

  2. Joint Composable Object Model and LVC Methodology

    NASA Technical Reports Server (NTRS)

    Rheinsmith, Richard; Wallace, Jeffrey; Bizub, Warren; Ceranowicz, Andy; Cutts, Dannie; Powell, Edward T.; Gustavson, Paul; Lutz, Robert; McCloud, Terrell

    2010-01-01

    Within the Department of Defense, multiple architectures are created to serve and fulfill one or several specific service or mission related LVC training goals. Multiple Object Models exist across and within those architectures and it is there that those disparate object models are a major source of interoperability problems when developing and constructing the training scenarios. The two most commonly used architectures are; HLA and TENA, with DIS and CTIA following close behind in terms of the number of users. Although these multiple architectures can share and exchange data the underlying meta-models for runtime data exchange are quite different, requiring gateways/translators to bridge between the different object model representations; while the Department of Defense's use of gateways are generally effective in performing these functions, as the LVC environment increases so too does the cost and complexity of these gateways. Coupled with the wide range of different object models across the various user communities we increase the propensity for run time errors, increased programmer stop gap measures during coordinated exercises, or failure of the system as a whole due to unknown or unforeseen incompatibilities. The Joint Composable Object Model (JCOM) project was established under an M&S Steering Committee (MSSC)-sponsored effort with oversight and control placed under the Joint Forces Command J7 Advanced Concepts Program Directorate. The purpose of this paper is to address the initial and the current progress that has been made in the following areas; the Conceptual Model Development Format, the Common Object Model, the Architecture Neutral Data Exchange Model (ANDEM), and the association methodology to allow the re-use of multiple architecture object models and the development of the prototype persistent reusable library.

  3. Les fluctuations supraconductrices dans le compose praseodyme-cerium-oxyde de cuivre

    NASA Astrophysics Data System (ADS)

    Renaud, Jacques

    Ce travail etudie les fluctuations supraconductrices dans le compose supraconducteur a haute temperature critique dope aux electrons Pr2-xCe xCuO4+delta. La technique utilisee pour sonder ces fluctuations est le transport electrique DC dans le plan ab. Il s'agit, a notre connaissance, de la premiere etude de ce type dans la classe generale des supraconducteurs a haute temperature critique dopes aux electrons et, plus particulierement, dans Pr2-xCe xCuO4+delta. De plus, l'etude est effectuee pour trois regimes de dopage, soit sous-dope x = 0.135, dopage optimal x = 0.15 et surdope x = 0.17. Les echantillons etudies sont des couches minces d'epaisseur plus grande que 100 nm crues par ablation laser. Les mesures electriques DC effectuees dans ce travail sont la resistance en reponse lineaire et les courbes IV en reponse non lineaire en fonction de la temperature. La mise en oeuvre experimentale de ces mesures a necessite une grande attention au filtrage et aux effets de chauffage a haut courant. Nous montrons que, sans cette attention, les donnees experimentales sont toujours erronees dans le regime pertinent pour nos echantillons. Les resultats pour le dopage optimal x = 0.15 sont expliques de facon tres convaincante dans le cadre de fluctuations purement 2D. D'abord, le regime des fluctuations gaussiennes est tres bien decrit par le modele d'Aslamazov-Larkin en deux dimensions. Ensuite, le regime de fluctuations critiques, se trouvant a plus basse temperature que le regime gaussien, est tres bien decrit par la physique 2D de Kosterlitz-Thouless. Dans cette analyse, les deux regimes ont des temperatures critiques coherentes entre elles, ce qui semble confirmer ce scenario 2D. Une analyse des donnees dans le cadre de fluctuations 3D est exploree mais donne des conclusions incoherentes. Les resultats pour les autres dopages sont qualitativement equivalents avec le dopage optimal et permettent donc une explication purement 2D. Par contre, contrairement au dopage optimal

  4. Sequoias, Mavericks, Open Doors...Composing Joan Tower

    ERIC Educational Resources Information Center

    Allsup, Randall Everett

    2011-01-01

    This essay interview with Joan Tower is a meditation on the importance of composing, understood as a process larger than the making of new sound combinations or musical scores, suggesting that the compositional act is self-educative and self-forming. Tower's musical life, one of teaching and learning, one of composing and self-composing, is an…

  5. Annuaire du bureau des Longitudes : guide de données astronomiques 2011 pour l'observation du ciel

    NASA Astrophysics Data System (ADS)

    Institut de Mécanique Céleste Et de Calcul Des Ephémérides (Imcce); Bureau Des Longitudes (Bdl)

    2010-07-01

    Destiné aux astronomes, professionnels ou amateurs, cet ouvrage se décompose de la façon suivante : Les trois premiers chapitres de cet ouvrage contiennent : les données sur les différents calendriers et leur concordance, les fêtes légales en France, les différentes échelles de temps, les dates de décrets sur les heures légales en France métropolitaine parues au Journal Officiel depuis 1916 ; des notions nécessaires à la compréhension et à l'emploi des éphémérides contenues dans l'ouvrage. Les chapitres suivant fournissent des éphémérides astronomiques : les positions du Soleil et de la Lune ; les positions des planètes et de leurs satellites ; les positions des astéroïdes et des comètes ; les explications et des données pour l'observation de la surface du Soleil, de la Lune et des planètes ; des cartes du ciel, une liste de constellations et les positions et occultations des étoiles ; des données sur les éclipses de Soleil et de Lune et sur les phénomènes astronomiques ; la liste des observatoires astronomiques les plus connus.

  6. Annuaire du bureau des Longitudes : guide de données astronomiques 2012 pour l'observation du ciel

    NASA Astrophysics Data System (ADS)

    Institut de Mécanique Céleste Et de Calcul Des Ephémérides (Imcce); Bureau Des Longitudes (Bdl)

    2011-07-01

    Destiné aux astronomes, professionnels ou amateurs, cet ouvrage se décompose de la façon suivante : Les trois premiers chapitres de cet ouvrage contiennent : les données sur les différents calendriers et leur concordance, les fêtes légales en France, les différentes échelles de temps, les dates de décrets sur les heures légales en France métropolitaine parues au Journal Officiel depuis 1916 ; des notions nécessaires à la compréhension et à l'emploi des éphémérides contenues dans l'ouvrage. Les chapitres suivant fournissent des éphémérides astronomiques : les positions du Soleil et de la Lune ; les positions des planètes et de leurs satellites ; les positions des astéroïdes et des comètes ; les explications et des données pour l'observation de la surface du Soleil, de la Lune et des planètes ; des cartes du ciel, une liste de constellations et les positions et occultations des étoiles ; des données sur les éclipses de Soleil et de Lune et sur les phénomènes astronomiques ; la liste des observatoires astronomiques les plus connus.

  7. Teaching Composing in Secondary School: A Case Study Analysis

    ERIC Educational Resources Information Center

    Bolden, Benjamin

    2009-01-01

    This article reports a case study of an experienced teacher of composing working with secondary school students in a large urban centre in Ontario, Canada. Results suggest authentic assignments connect student composing to the "real world", and so have meaning and life beyond the music classroom. Teachers can facilitate the development of…

  8. 16 CFR 301.20 - Fur products composed of pieces.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Fur products composed of pieces. 301.20 Section 301.20 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULES AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.20 Fur products composed...

  9. 16 CFR 301.20 - Fur products composed of pieces.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Fur products composed of pieces. 301.20 Section 301.20 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULES AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.20 Fur products composed of pieces. (a) Where fur products, or fur mats...

  10. 16 CFR 301.20 - Fur products composed of pieces.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Fur products composed of pieces. 301.20 Section 301.20 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULES AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.20 Fur products composed of pieces. (a) Where fur products, or fur mats...

  11. 16 CFR 301.20 - Fur products composed of pieces.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Fur products composed of pieces. 301.20 Section 301.20 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULES AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.20 Fur products composed...

  12. 16 CFR 301.20 - Fur products composed of pieces.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Fur products composed of pieces. 301.20 Section 301.20 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULES AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.20 Fur products composed...

  13. Syllabus for a Women Studies Course on Women Composers.

    ERIC Educational Resources Information Center

    Hayes, Deborah

    An upper division college-level course dealing with women composers for both music majors and nonmusic majors is outlined. The course provides an historical and analytical survey of western music through works composed by women, with emphasis on the 19th and 20th centuries. Students listen to music, participate in class discussions, and listen to…

  14. Coding the Composing Process: A Guide for Teachers and Researchers.

    ERIC Educational Resources Information Center

    Perl, Sondra

    Designed for teachers and researchers interested in the study of the composing process, this guide introduces a method of analysis that can be applied to data from a range of different cases. Specifically, the guide offers a simple, direct coding scheme for describing the movements occurring during composing that involves four procedures: teaching…

  15. Composing in Public: The Ambient Audiences of a Writing Lab

    ERIC Educational Resources Information Center

    Hall, Matthew

    2015-01-01

    Although scholars have investigated the ways youths individually enact composing practices and the impact of audience on these practices, this study examines the impact of an audience physically present while composing in a shared, public space--an ambient audience. Blurring the line between traditional notions of audience and collaborator through…

  16. The Links between Handwriting and Composing for Y6 Children

    ERIC Educational Resources Information Center

    Medwell, Jane; Strand, Steve; Wray, David

    2009-01-01

    Although handwriting is often considered a matter of presentation, a substantial body of international research suggests that the role of handwriting in children's composing has been neglected. Automaticity in handwriting is now seen as of key importance in composing but this proposition is relatively untested in the UK and the assumption has been…

  17. How Composers Approach Teaching Composition: Strategies for Music Teachers

    ERIC Educational Resources Information Center

    Randles, Clint; Sullivan, Mark

    2013-01-01

    Composition pedagogy is explored from the perspective of a composer and a music teacher educator in this article. The primary goal is to help practicing music teachers develop strategies that will encourage students to create original music. The authors provide reflection about the process of helping students compose on the basis of personal…

  18. Collaborative Composing in High School String Chamber Music Ensembles

    ERIC Educational Resources Information Center

    Hopkins, Michael T.

    2015-01-01

    The purpose of this study was to examine collaborative composing in high school string chamber music ensembles. Research questions included the following: (a) How do high school string instrumentalists in chamber music ensembles use verbal and musical forms of communication to collaboratively compose a piece of music? (b) How do selected variables…

  19. Hypermedia Composing: Questions Arising from Writing in Three Dimensions.

    ERIC Educational Resources Information Center

    Garthwait, Abigail

    2001-01-01

    Observes four sixth graders composing nonfiction projects for an integrated unit on Canadian studies, using hypermedia. Ponders issues raised when students compose in hypermedia including evaluating nontraditional projects, developing a sense of audience, conventions of the medium, use of visuals to convey information, engaged students, and…

  20. The composing process of technical writers: A preliminary study

    NASA Technical Reports Server (NTRS)

    Mair, D.; Roundy, N.

    1981-01-01

    The assumption that technical writers compose as do other writers is tested. The literature on the composing process, not limited to the pure or applied sciences, was reviewed, yielding three areas of general agreement. The composing process (1) consists of several stages, (2) is reflexive, and (3) may be mastered by means of strategies. Data on the ways technical writers compose were collected, and findings were related to the three areas of agreement. Questionnaires and interviews surveying 70 writers were used. The disciplines represented by these writers included civil, chemical, agricultural, geological, mechanical, electrical, and petroleum engineering, chemistry, hydrology, geology, and biology. Those providing consulting services, or performing research. No technical editors or professional writers were surveyed, only technicians, engineers, and researchers whose jobs involved composing reports. Three pedagogical implications are included.

  1. Fabrication of PbS thin films composed of highly (200)-oriented nano-/micro-rods in deep eutectic solvent

    NASA Astrophysics Data System (ADS)

    Chen, Jun; Zhang, Jianjun; Xu, Huifang; Ouyang, Yan; Zhan, Funan; Li, Qiang

    2015-08-01

    PbS thin films composed of highly (200)-oriented shuttle-like nano-/micro-rods were successfully fabricated on glass substrates by the environment friendly ionothermal method at 140 °C in deep eutectic solvent (DES). The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), ultraviolet-visible (UV-vis) and photoluminescence (PL) spectra, respectively. The possible mechanism of the oriented growth of PbS nano-/micro-rods was discussed. The PbS thin films composed of shuttle-like nano-/micro-rods exhibited a large absorbance property in the wavelength range of 350-1100 nm, and moreover, the PL spectrum had a broad emission band centered at 490 nm. The shuttle-like PbS nano-/micro-rods-based thin films might have potential application in solar cells.

  2. Stroke, music, and creative output: Alfred Schnittke and other composers.

    PubMed

    Zagvazdin, Yuri

    2015-01-01

    Alfred Schnittke (1934-1998), a celebrated Russian composer of the twentieth century, suffered from several strokes which affected his left cerebral hemisphere. The disease, however, did not diminish his musical talent. Moreover, he stated that his illness in a way facilitated his work. The composer showed amazingly high productivity after his first and second injuries of the central nervous system. The main topic of this chapter is the effect of strokes on Schnittke's output, creativity, and style of music. A brief biography of the composer with the chronology of his brain hemorrhages is included. In addition, the influence of cerebrovascular lesions on creative potential of other prominent composers such as Benjamin Britten, Jean Langlais, Vissarion Shebalin, Igor Stravinsky, and Ira Randall Thompson is discussed. PMID:25684289

  3. Des ballons pour demain

    NASA Astrophysics Data System (ADS)

    Régipa, R.

    A partir d'une théorie sur la détermination des formes et des contraintes globales d'un ballon de révolution, ou s'en rapprochant, une nouvelle famille de ballons a été définie. Les ballons actuels, dits de ``forme naturelle'', sont calculés en général pour une tension circonférencielle nulle. Ainsi, pour une mission donnée, la tension longitudinale et la forme de l'enveloppe sont strictement imposées. Les ballons de la nouvelle génération sont globalement cylindriques et leurs pôles sont réunis par un câble axial, chargé de transmettre une partie des efforts depuis le crochet (pôle inférieur), directement au pôle supérieur. De plus, la zone latérale cylindrique est soumise à un faible champ de tensions circonférencielles. Ainsi, deux paramètres permettent de faire évoluer la distribution des tensions et la forme de l'enveloppe: - la tension du câble de liaison entre pôles (ou la longueur de ce câble) - la tension circonférencielle moyenne désirée (ou le rayon du ballon). On peut donc calculer et réaliser: - soit des ballons de forme adaptée, comme les ballons à fond plat pour le bon fonctionnement des montgolfières infrarouge (projet MIR); - soit des ballons optimisés pour une bonne répartition des contraintes et une meilleure utilisation des matériaux d'enveloppe, pour l'ensemble des programmes stratosphériques. Il s'ensuit une économie sensible des coûts de fabrication, une fiabilité accrue du fonctionnement de ces ballons et une rendement opérationnel bien supérieur, permettant entre autres, d'envisager des vols à très haute altitude en matériaux très légers.

  4. Amputation des quatre membres

    PubMed Central

    Feruzi, Maruis Kitembo; Milindi, Cédrick Sangwa; Zabibu, Mireille Kakinga; Mulefu, Jules Panda; Katombe, Francois Tshilombo

    2014-01-01

    Les auteurs présentent les cas d'amputation des quatre membres réalisée chez trois patients différents. Ce sont des amputations réalisées pour chaque patient au cours d'une seule hospitalisation et en un seul temps opératoire. Deux patients pour gangrène sèche infectée et un pour amputation traumatique des quatre membres. L'amputation d'urgence a été pratiquée en premier temps suivie de remodelage des moignons d'amputation en second temps. L’évolution de tous les patients a été bonne. PMID:25469177

  5. A membrane page composer - Further developments. [for holographic memory system

    NASA Technical Reports Server (NTRS)

    Cosentino, L. S.; Stewart, W. C.

    1974-01-01

    Membrane page composers were made and were evaluated in a simulated holographic optical memory system. Calculated and experimentally determined electromechanical and optical characteristics of the circular membrane light valves used on the arrays are shown to be in close agreement. Several operating prototypes of 8 x 8 and 16 x 16 elements were produced. Measurements were made of switching time, optical contrast, and dynamic storage time of many cells on the devices. Digital patterns were stored in the arrays. The performance required of the page composer as a component of an optical memory system is considered. The fabrication techniques used can be easily extended to larger arrays.

  6. Composing with New Technology: Teacher Reflections on Learning Digital Video

    ERIC Educational Resources Information Center

    Bruce, David L.; Chiu, Ming Ming

    2015-01-01

    This study explores teachers' reflections on their learning to compose with new technologies in the context of teacher education and/or teacher professional development. English language arts (ELA) teachers (n = 240) in 15 courses learned to use digital video (DV), completed at least one DV group project, and responded to open-ended survey…

  7. "Convince Me!" Valuing Multimodal Literacies and Composing Public Service Announcements

    ERIC Educational Resources Information Center

    Selfe, Richard J.; Selfe, Cynthia L.

    2008-01-01

    For some teachers, the increasing attention to digital and multimodal composing in English and Language Arts classrooms has brought into sharp relief the profession's investment in print as the primary means of expression. Although new forms of communication that combine words, still and moving images, and animation have begun to dominate digital…

  8. How One Class with One Computer Composed Music

    ERIC Educational Resources Information Center

    Siegel, Jack

    2004-01-01

    Music composition is a rewarding activity for students. Through composition, teachers not only address National Standard 4 (composing and arranging music within specified guidelines), but also cover other areas of the music curriculum such as singing, notation, improvisation, form, style, tempo, dynamics, music vocabulary, and assessment. During…

  9. When Did Classic Composers Make Their Best Work?

    ERIC Educational Resources Information Center

    Franses, Philip Hans

    2016-01-01

    This Research Note shows that classic composers created their best works when they were at a similar age when creators in other domains did their best work, namely when they were at an age that represented around 60% of their life span. This finding is very similar to earlier results for painters and authors.

  10. The Poetics of Computers: Composing Relationships with Technology.

    ERIC Educational Resources Information Center

    Longo, Bernadette; Reiss, Donna; Selfe, Cynthia L.; Young, Art

    2003-01-01

    Describes a course with three primary goals: to help students reflect on the complex relationship between humans and technology; to reflect on students' responsibility for shaping this relationship in contemporary contexts; and to provide opportunities within which to practice composing this relationship in personal terms. Concludes that in such…

  11. Quiet Grove in a Savage Garden: A Composer's Bicameral Reality

    ERIC Educational Resources Information Center

    Bohlen, Donald

    2004-01-01

    This author, a composer, states that music has been the primal generator of his existence and the definition of living creatively; and that understanding the bicameral reality of creativity through a study of the nature of consciousness involves a symbiotic host of disciplines. In the study of the occurrence of "creativity," consciousness as well…

  12. Composing Songs for Teaching Science to College Students

    ERIC Educational Resources Information Center

    Yee Pinn Tsin, Isabel

    2015-01-01

    Recent studies have shown that songs may enhance learning as they function as mnemonic devices to increase memorability. In this research, songs based on the more difficult subtopics in Chemistry were composed, encompassing many formulas, equations and facts to be remembered. This technique of song composition can be used in any subject, any point…

  13. The Composing Processes of Unskilled Writers at the College Level.

    ERIC Educational Resources Information Center

    Perl, Sondra

    This paper uses five case studies of unskilled writers at the college level to provide insights into the composing process. Each student's writing process was tape-recorded and observed by the instructor in four sessions. The tapes and written observations were charted and analyzed for exhibited behavior patterns in comparison to the written…

  14. To Compose: Teaching Writing in the High School.

    ERIC Educational Resources Information Center

    Newkirk, Thomas, Ed.

    The twelve essays in this collection, selected by leading teacher educators, explore the composition process and composition instruction. The first essay, "Toward Righting Writing" by Arthur Diagon, serves as a prologue while the second section, "getting started," consists of "A Way of Writing" by William Stafford, "Understanding Composing" by…

  15. The Composing Process: A Critical Review of Some Recent Studies.

    ERIC Educational Resources Information Center

    Crismore, Avon

    Six of the 10 existing research studies that attempt to characterize the composing process by examining certain components and behaviors are critically reviewed in this paper. For each study, the aims and data gathering and sampling procedures are described, and the findings, interpretations, design, and rationale of the research are critically…

  16. Teaching Effective Communication Skills with ACE: Analyzing, Composing, & Evaluating

    ERIC Educational Resources Information Center

    Snyder, Lisa Gueldenzoph; Shwom, Barbara

    2011-01-01

    Most business communication classes teach students to use a writing process to compose effective documents. Students practice the process by applying it to various types of writing with various purposes-reports, presentations, bad news letters, persuasive memos, etc. However, unless students practice that process in other contexts outside of the…

  17. Circularly polarized printed arrays composed of strip dipoles and slots

    NASA Astrophysics Data System (ADS)

    Ito, Koichi

    1987-04-01

    This paper presents circularly polarized printed arrays composed of strip dipoles and slots (CP-PASS). A design method for CP-PASS is described on the basis of its equivalent circuit model. A linear array with a Chebyshev pattern and a middle-gain planar array are designed and measured at S band.

  18. Beyond the Enthymeme: Sorites, Critical Thinking, and the Composing Process.

    ERIC Educational Resources Information Center

    Hill, Carolyn

    A teacher presents a writing exercise designed to facilitate audience-directed, critical thinking during the process of composing, that starts students thinking in terms of sorites and enthymemes. Students first read a CIA manual, "Psychological Operations in Guerrilla Warfare," that instructs the Contra guerrillas in illegal acts and then free…

  19. Performing Stenographic Activities. Compose Correspondence. Student's Manual and Instructor's Manual.

    ERIC Educational Resources Information Center

    Harrison, Pam

    Supporting performance objective 71 of the V-TECS (Vocational-Technical Education Consortium of States) Secretarial Catalog, both a set of student materials and an instructor's manual on composing correspondence are included in this packet. (The packet is the fourth in a set of four on performing stenographic activities--CE 016 973-976.) The…

  20. Readers as Writers Composing from Sources. Technical Report No. 18.

    ERIC Educational Resources Information Center

    Spivey, Nancy Nelson; King, James R.

    A study of discourse synthesis (readers/writers composing new texts by selecting, organizing, and connecting content from source texts) examined the performance of accomplished and less accomplished readers in the 6th, 8th, and 10th grades on a report-writing task. Over a 3-day period 60 English/language arts students wrote informational reports…

  1. Conversations with American Composers: Ev Grimes Interviews William Schuman.

    ERIC Educational Resources Information Center

    Grimes, Ev

    1986-01-01

    Born in 1910, composer William Schuman has been deeply involved with music education, first as a college professor and later a president of the Julliard School of Music. In this interview, Schuman talks about what music means to him, his teaching career, and music in general education. (RM)

  2. Conversations with American Composers: Ev Grimes Interviews Otto Luening.

    ERIC Educational Resources Information Center

    Grimes, Ev

    1986-01-01

    Otto Luening, one of the pioneers in the development of tape composition, talks about a variety of topics, including the education of musicians, the relationship between composer and teacher, his class for non-music majors, the musical training a teacher should have, and changes needed in music education. (RM)

  3. Etude des phenomenes dynamiques ultrarapides et des caracteristiques impulsionnelles d'emission terahertz du supraconducteur YBCO

    NASA Astrophysics Data System (ADS)

    Savard, Stephane

    Les premieres etudes d'antennes a base de supraconducteurs a haute temperature critique emettant une impulsion electromagnetique dont le contenu en frequence se situe dans le domaine terahertz remontent a 1996. Une antenne supraconductrice est formee d'un micro-pont d'une couche mince supraconductrice sur lequel un courant continu est applique. Un faisceau laser dans le visible est focalise sur le micro-pont et place le supraconducteur dans un etat hors-equilibre ou des paires sont brisees. Grace a la relaxation des quasiparticules en surplus et eventuellement de la reformation des paires supraconductrices, nous pouvons etudier la nature de la supraconductivite. L'analyse de la cinetique temporelle du champ electromagnetique emis par une telle antenne terahertz supraconductrice s'est averee utile pour decrire qualitativement les caracteristiques de celle-ci en fonction des parametres d'operation tels que le courant applique, la temperature et la puissance d'excitation. La comprehension de l'etat hors-equilibre est la cle pour comprendre le fonctionnement des antennes terahertz supraconductrices a haute temperature critique. Dans le but de comprendre ultimement cet etat hors-equilibre, nous avions besoin d'une methode et d'un modele pour extraire de facon plus systematique les proprietes intrinseques du materiau qui compose l'antenne terahertz a partir des caracteristiques d'emission de celle-ci. Nous avons developpe une procedure pour calibrer le spectrometre dans le domaine temporel en utilisant des antennes terahertz de GaAs bombarde aux protons H+ comme emetteur et detecteur. Une fois le montage calibre, nous y avons insere une antenne emettrice dipolaire de YBa 2Cu3O7-delta . Un modele avec des fonctions exponentielles de montee et de descente du signal est utilise pour lisser le spectre du champ electromagnetique de l'antenne de YBa 2Cu3O7-delta, ce qui nous permet d'extraire les proprietes intrinseques de ce dernier. Pour confirmer la validite du modele

  4. Composing Texts, Composing Lives.

    ERIC Educational Resources Information Center

    Perl, Sondra

    1994-01-01

    Using composition, reader response, critical, and feminist theories, a teacher demonstrates how adult students respond critically to literary texts and how teachers must critically analyze the texts of their teaching practice. Both students and teachers can use writing to bring their experiences to interpretation. (SK)

  5. Modeling and Composing Scenario-Based Requirements with Aspects

    NASA Technical Reports Server (NTRS)

    Araujo, Joao; Whittle, Jon; Ki, Dae-Kyoo

    2004-01-01

    There has been significant recent interest, within the Aspect-Oriented Software Development (AOSD) community, in representing crosscutting concerns at various stages of the software lifecycle. However, most of these efforts have concentrated on the design and implementation phases. We focus in this paper on representing aspects during use case modeling. In particular, we focus on scenario-based requirements and show how to compose aspectual and non-aspectual scenarios so that they can be simulated as a whole. Non-aspectual scenarios are modeled as UML sequence diagram. Aspectual scenarios are modeled as Interaction Pattern Specifications (IPS). In order to simulate them, the scenarios are transformed into a set of executable state machines using an existing state machine synthesis algorithm. Previous work composed aspectual and non-aspectual scenarios at the sequence diagram level. In this paper, the composition is done at the state machine level.

  6. A Design for Composing and Extending Vehicle Models

    NASA Technical Reports Server (NTRS)

    Madden, Michael M.; Neuhaus, Jason R.

    2003-01-01

    The Systems Development Branch (SDB) at NASA Langley Research Center (LaRC) creates simulation software products for research. Each product consists of an aircraft model with experiment extensions. SDB treats its aircraft models as reusable components, upon which experiments can be built. SDB has evolved aircraft model design with the following goals: 1. Avoid polluting the aircraft model with experiment code. 2. Discourage the copy and tailor method of reuse. The current evolution of that architecture accomplishes these goals by reducing experiment creation to extend and compose. The architecture mechanizes the operational concerns of the model's subsystems and encapsulates them in an interface inherited by all subsystems. Generic operational code exercises the subsystems through the shared interface. An experiment is thus defined by the collection of subsystems that it creates ("compose"). Teams can modify the aircraft subsystems for the experiment using inheritance and polymorphism to create variants ("extend").

  7. Measuring image quality in overlapping areas of panoramic composed images

    NASA Astrophysics Data System (ADS)

    Mitjà, Carles; Bover, Toni; Escofet, Jaume

    2012-06-01

    Several professional photographic applications uses the merging of consecutive overlapping images in order to obtain bigger files by means of stitching techniques or extended field of view (FOV) for panoramic images. All of those applications share the fact that the final composed image is obtained by overlapping the neighboring areas of consecutive individual images taken as a mosaic or a series of tiles over the scene, from the same point of view. Any individual image taken with a given lens can carry residual aberrations and several of them will affect more probably the borders of the image frame. Furthermore, the amount of distortion aberration present in the images of a given lens will be reversed in position for the two overlapping areas of a pair of consecutive takings. Finally, the different images used in composing the final one have corresponding overlapping areas taken with different perspective. From all the previously stated can be derived that the software employed must remap all the pixel information in order to resize and match image features in those overlapping areas, providing a final composed image with the desired perspective projection. The work presented analyse two panoramic format images taken with a pair of lenses and composed by means of a state of the art stitching software. Then, a series of images are taken to cover an FOV three times the original lens FOV, the images are merged by means of a software of common use in professional panoramic photography and the final image quality is evaluated through a series of targets positioned in strategic locations over the whole taking field of view. That allows measuring the resulting Resolution and Modulation Transfer Function (MTF). The results are shown compared with the previous measures on the original individual images.

  8. Soft elasticity in solids composed of ellipse-shaped particles

    NASA Astrophysics Data System (ADS)

    Mkhonta, Simiso K.; Vernon, Daniel; Elder, K. R.; Grant, Martin

    2013-03-01

    We present a method for studying the influence of internal rotational degrees of freedom on the elastic properties of crystals composed of ellipsoidal particles. We derive the conditions under which a stretched-triangular lattice of ellipsoidal particles can exhibit a vanishing shear modulus. Analytical predictions are confirmed with numerical calculations. Numerical results also show that internal rotational modes can delay the proliferation of dislocations in the plastic regime.

  9. 1. General view, outbuildings. The seed house composed of the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. General view, outbuildings. The seed house composed of the greenhouse, a storeroom (shed), a classroom (over a former ice pit), and a kitchen (over a cellar)-stands on the right. The barn roof is visible at center and the gift shop (former stable) stands on the left (Note the carved stone posts framing the gateway). - John Bartram House & Garden, Greenhouse, 54th Street & LIndbergh Boulevard, Philadelphia, Philadelphia County, PA

  10. A design study of a photorefractive page composer

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A laboratory demonstration and preliminary system analysis of a page composer designed to have the dual advantages of low optical loss and small size, were reported. The current page composer is optically addressed and functions by virtue of optically induced refractive index changes in the active material. Laboratory demonstrations of the device were successfully performed using 10 x 10 bit and 128 x 128 bit data arrays. It was established that the only significant obstacle to the construction of a brass-board model working at megabit data rates is the lack of sensitivity of the photorefractive materials which were considered during the course of this study. Possible materials for future consideration are the photoplastics. While they have more than the required sensitivity, their stability and suitability for double exposure holography was not investigated. If a sufficiently sensitive material is found, then the photorefractive page composer could be built to perform in a highly efficient fashion which would result in a overall reduction of the size of the memory system and an easing of the requirements upon the sensitivity of the holographic recording material.

  11. Des Vents et des Jets Astrophysiques

    NASA Astrophysics Data System (ADS)

    Sauty, C.

    well expected result from the theory. Although, collimation may be conical, paraboloidal or cylindrical (Part 4), cylindrical collimation is the more likely to occur. The shape of outflows may then be used as a tool to predict physical conditions on the flows or on their source. L'éjection continue de plasma autour d'objets massifs est un phénomène largement répandu en astrophysique, que ce soit sous la forme du vent solaire, de vents stellaires, de jets d'étoiles en formation, de jets stellaires autour d'objets compacts ou de jets extra-galactiques. Cette zoologie diversifiée fait pourtant l'objet d'un commun effort de modélisation. Le but de cette revue est d'abord de présenter qualitativement le développement, depuis leur origine, des diverses théories de vents (Partie 1) et l'inter disciplinarité dans ce domaine. Il s'agit d'une énumération, plus ou moins exhaustive, des idées proposées pour expliquer l'accélération et la morphologie des vents et des jets, accompagnée d'une présentation sommaire des aspects observationnels. Cette partie s'abstient de tout aspect faisant appel au formalisme mathématique. Ces écoulements peuvent être décrits, au moins partiellement, en résolvant les équations magnétohydrodynamiques, axisymétriques et stationnaires. Ce formalisme, à la base de la plupart des théories, est exposé dans la Partie 2. Il permet d'introduire quantitativement les intégrales premières qu'un tel système possède. Ces dernières sont amenées à jouer un rôle important dans la compréhension des phénomènes d'accélération ou de collimation, en particulier le taux de perte de masse, le taux de perte de moment angulaire ou l'énergie du rotateur magnétique. La difficulté de modélisation réside dans l'existence de points critiques, propres aux équations non linéaires, qu'il faut franchir. La nature physique et la localisation de ces points critiques fait l'objet d'un débat important car ils sont la clef de voute de la r

  12. Theory, fabrication and applications of metamaterials composed of cylinders

    NASA Astrophysics Data System (ADS)

    Strickland, Diana

    In this work we design a new type of hyperlens composed of nanowires, and numerically demonstrate its ability to resolve closely spaced and otherwise indistinguishable features of an imaged object in the far field. Conversely, we demonstrate the ability of a concentrator to focus incident radiation into an area much smaller than a wave length. To overcome limitations in fabricating materials such as the nanowire composites used in the applications above as well as other materials composed of cylindrical structures, we propose the newly patented method, #US2015/0017466A1, that features initial masked patterning and partial self-assembly, resulting in a relatively simple, inexpensive process with a flexible flow and many constituent material options, capable of forming composites with diverse functionalities. Although modeling the effective properties of cylinder-based media has been the focus of considerable research in the field of Metamaterials, surprisingly enough, no complete and fully dynamic model of such cylinders' response to incident radiation existed. Based on Mie scattering theory, we derive the complete dynamic polarizability tensor for circular, azimuthally symmetric cylinders excited by an arbitrary field distribution, and provide compact expressions for all of its elements. Interestingly, magnetoelectric effects are shown to arise at oblique incidence, even in the case of centrosymmetric achiral thin cylinders, associated with a weak form of spatial dispersion. We expect the polarizabilities to find applications in antenna design, in metamaterial design, and to improve the physical understanding of the wave interaction and spatial dispersion in artificial materials composed of elongated inclusions such as wire media.

  13. System Composer: Technology for rapid system integration and remote collaboration

    SciTech Connect

    Davies, B.R.; Palmquist, R.D.

    1996-03-01

    Sandia National Laboratories has developed an approach to the design, evaluation, deployment and operation of intelligent systems which is called System Composer. This toolkit provides an infrastructure and architecture for robot and automation system users to readily integrate system components and share mechatronic, sensor, and information resources over networks. The technology described in this paper provides a framework for real-time collaboration between researchers, manufacturing entities, design entities, and others without regard to relative location. An overview of the toolkit including its elements and architecture is provided along with examples of its use.

  14. Liquid Crystalline Networks Composed of Pentagonal, Square, and Triangular Cylinders

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Zeng, Xiangbing; Baumeister, Ute; Ungar, Goran; Tschierske, Carsten

    2005-01-01

    T-shaped molecules are designed in such a way that they self-organize into nanoscale liquid crystalline honeycombs based on polygons with any chosen number of sides. One of the phases reported here is a periodic organization of identical pentagonal cylinders; the other one is a structure composed of square-shaped and triangular cylinders in the ratio 2:1. These two different packing motifs represent duals of the same topological class. The generalization of the concept applied here allows the prediction of a whole range of unusual complex liquid crystalline phases.

  15. Fluctuations quantiques et instabilites structurales dans les conducteurs a basse dimensionalite

    NASA Astrophysics Data System (ADS)

    Dikande, Alain Moise

    Un engouement particulier s'est manifeste ces dernieres annees pour les systemes electroniques fortement correles, ce en rapport avec l'immense richesse de leurs proprietes physiques. En general, ces proprietes sont induites par la presence d'interactions entre electrons qui, combinees a la structure du reseau moleculaire, donnent parfois lieu a une tres grande variete de phases electroniques et structurales ayant des incidences directes sur les phenomenes de transport dans ces materiaux. Les systemes electroniques couples a un reseau moleculaire et designes systemes electron-phonon font partie de cette classe de materiaux qui ont recemment capte l'attention, en raison notamment de la competition entre plusieurs echelles d'energie dans un environnement caracterise par une forte anisotropie cristalline et une dynamique moleculaire assez importante. En effet, en plus des proprietes electroniques et structurales particulieres la dimensionalite de ces systemes contribue egalement a leur richesse. Ainsi, une tres forte anisotropie structurale peut rehausser de facon considerable l'importance des interactions entre electrons et entre molecules constituant le reseau au point ou la physique du systeme soit regie par de tres fortes fluctuations. Ce dernier contexte est devenu un domaine a part de la physique des systemes fortement correles, a savoir celui des les phenomenes critiques quantiques . Parmi les systemes electron-phonon, on retrouve les composes inorganique KCP et organique TTF-TCNQ decouverts durant les annees 70, et explores en profondeur a cause de leur tendance vers une instabilite du type onde de densite de charge a basse temperature. Ces composes, en general designes systemes de Peierls en reference a l'instabilite de leurs structures electroniques regie par le reseau moleculaire, ont recemment connu un regain d'interet a la lumiere des nouveaux developpements dans les techniques de caracterisation des structures electroniques ainsi que sur le plan de

  16. Amyloid fibrils composed of hexameric peptides attenuate neuroinflammation.

    PubMed

    Kurnellas, Michael P; Adams, Chris M; Sobel, Raymond A; Steinman, Lawrence; Rothbard, Jonathan B

    2013-04-01

    The amyloid-forming proteins tau, αB crystallin, and amyloid P protein are all found in lesions of multiple sclerosis (MS). Our previous work established that amyloidogenic peptides from the small heat shock protein αB crystallin (HspB5) and from amyloid β fibrils, characteristic of Alzheimer's disease, were therapeutic in experimental autoimmune encephalomyelitis (EAE), reflecting aspects of the pathology of MS. To understand the molecular basis for the therapeutic effect, we showed a set of amyloidogenic peptides composed of six amino acids, including those from tau, amyloid β A4, major prion protein (PrP), HspB5, amylin, serum amyloid P, and insulin B chain, to be anti-inflammatory and capable of reducing serological levels of interleukin-6 and attenuating paralysis in EAE. The chaperone function of the fibrils correlates with the therapeutic outcome. Fibrils composed of tau 623-628 precipitated 49 plasma proteins, including apolipoprotein B-100, clusterin, transthyretin, and complement C3, supporting the hypothesis that the fibrils are active biological agents. Amyloid fibrils thus may provide benefit in MS and other neuroinflammatory disorders. PMID:23552370

  17. Surgical operation using lighting goggle composed of white LED arrays

    NASA Astrophysics Data System (ADS)

    Shimada, Junichi; Kawakami, Yoichi; Fujita, Shigeo

    2001-12-01

    Everywhere in the world, the highest quality and quantity of lighting is required during the surgical operations. However, the surgical approach has had many types and various angles, common ceiling surgical halogen lighting system cannot provide an adequate amount of beams because the surgeons' heads hinder the illuminations from reaching the operation field. Here, we newly design surgical lighting system composed of white LEDs equipped on both sides of goggles, which controls the lighting beams to the gazing point. With this system, it is just needed for surgeons to wear light plastic goggles with high quality LEDs made by Nichia. In fact, we have succeeded in the first internal shunt operation in the left forearm using the surgical LED lighting system on 11th Sept 2000. The electrical power for the system was supplied from lithium-ion battery for 2 hours. Since the white LEDs used were composed of InGaN-blue-emitters and YAG-yellow-phosphors, the color rendering property was not sufficient in the reddish colors. Therefore, in the next approach, it is very important to develop the spectral distribution of white LED to render inherent color of raw flesh such as skin, blood, fat tissue and internal organs. To improve the color rendering in red colors, some adjustments should be given in the fluorescents layers. Design of goggle is also very important for cutting into the real practical market of white LEDs.

  18. Medical lighting composed of LED arrays for surgical operation

    NASA Astrophysics Data System (ADS)

    Shimada, Junichi; Kawakami, Yoichi; Fujita, Shigeo

    2001-05-01

    Everywhere in the world, the highest quality and quantity of lighting is required during the surgical operations. However, the surgical approach has had many types and various angles, common ceiling surgical halogen lighting system cannot provide an adequate amount of beams because the surgeons' heads hinder the illuminations from reaching the operation field. Here, we newly design surgical lighting system composed of white LEDs equipped on both sides of goggles, which controls the lighting beams to the gazing point. With this system, it is just needed for surgeons to wear light plastic goggles with high quality LEDs made by Nichia. In fact, we have succeeded in the first internal shunt operation in the left forearm using the surgical LED lighting system on 11th Sept 2000. The electrical power for the system was supplied from lithium-ion battery for 2 hours. Since the white LEDs used were composed of InGaN- blue-emitters and YAG-yellow-phosphors, the color rendering property was not sufficient in the reddish colors. Therefore, in the next approach, it is very important to develop the spectral distribution of white LED to render inherent color of raw flesh such as skin, blood, fat tissue and internal organs.

  19. Amyloid Fibrils Composed of Hexameric Peptides Attenuate Neuroinflammation

    PubMed Central

    Kurnellas, Michael P.; Adams, Chris M.; Sobel, Raymond A.; Steinman, Lawrence; Rothbard, Jonathan B.

    2013-01-01

    Amyloid forming proteins Tau, alpha B crystallin, and amyloid P protein are all found in lesions of multiple sclerosis (MS). Our previous work established that amyloidogenic peptides from the small heat shock protein, alpha B crystallin(HspB5), and from amyloid β fibrils, characteristic of Alzheimer’s disease, were therapeutic in experimental autoimmune encephalomyelitis (EAE), reflecting aspects of the pathology of MS. To understand the molecular basis for the therapeutic effect, a set of amyloidogenic peptides composed of six amino acids, including those from tau, amyloid β A4, major prion protein (PrP), HspB5, amylin, serum amyloid P (SAP), and insulin B chain were shown to be anti-inflammatory, capable of reducing serological levels of IL-6, and attenuating paralysis in EAE. The chaperone function of the fibrils correlates with the therapeutic outcome. Fibrils composed of Tau 623–628 precipitated 49 plasma proteins, including apolipoprotein B-100, clusterin, transthyretin, and complement C3, supporting the hypothesis that the fibrils are active biological agents. Amyloid fibrils thus may provide benefit in MS and other neuroinflammatory disorders. PMID:23552370

  20. Domain-Specific Languages for Composing Signature Discovery Workflows

    SciTech Connect

    Jacob, Ferosh; Gray, Jeff; Wynne, Adam S.; Liu, Yan; Baker, Nathan A.

    2012-10-23

    Domain-agnostic signature discovery entails investigation across multiple scientific disciplines. The breadth and cross-disciplinary nature of this work requires that existing executables be integrated with new capabilities into workflows, representing a wide range of user tasks. An algorithm may be written in multiple programming languages for various hardware platforms, and so workflow composition requires integrating executables from any number of remote hosts. This raises an engineering issue on how to generate web service wrappers for these heterogeneous executables and to compose them into a scientific workflow environment (e.g., Taverna). In this paper, we introduce two simple Domain-Specific Languages (DSLs) to automate these processes. Our Service Description Language (SDL) describes key elements of a signature discovery service and automatically generates its implementation code. The Workflow Description Language (WDL) describes the pipeline of services and generates deployable artifacts for the Taverna workflow management system. We demonstrate our approach with a real-world workflow composed of services wrapping remote executables.

  1. Ecological interaction and phylogeny, studying functionality on composed networks

    NASA Astrophysics Data System (ADS)

    Cruz, Claudia P. T.; Fonseca, Carlos Roberto; Corso, Gilberto

    2012-02-01

    We study a class of composed networks that are formed by two tree networks, TP and TA, whose end points touch each other through a bipartite network BPA. We explore this network using a functional approach. We are interested in how much the topology, or the structure, of TX (X=A or P) determines the links of BPA. This composed structure is a useful model in evolutionary biology, where TP and TA are the phylogenetic trees of plants and animals that interact in an ecological community. We make use of ecological networks of dispersion of fruits, which are formed by frugivorous animals and plants with fruits; the animals, usually birds, eat fruits and disperse their seeds. We analyse how the phylogeny of TX determines or is correlated with BPA using a Monte Carlo approach. We use the phylogenetic distance among elements that interact with a given species to construct an index κ that quantifies the influence of TX over BPA. The algorithm is based on the assumption that interaction matrices that follows a phylogeny of TX have a total phylogenetic distance smaller than the average distance of an ensemble of Monte Carlo realisations. We find that the effect of phylogeny of animal species is more pronounced in the ecological matrix than plant phylogeny.

  2. Music and the Nature: Input of the Czech Composers

    NASA Astrophysics Data System (ADS)

    Nemec, Vaclav; Nemcova, Lidmila

    2014-05-01

    Extraordinary occasions for art of any kind - music, creative graphic and plastic arts, literature (classic, modern incl. science fiction), theatre, cinema, etc. - exist to harmonise individual personal interests with those of the humanity well-being and of the Nature and also to cultivate individual spirituality and the appropriate values. Arts can be applied as irreplaceable means for making any human being better, for improving his sense for solidarity and for increasing his ethical sensibility. An interest for the art should be cultivated already since the childhood. - How much of inspiration for numerous composers all over the world has been given by the Nature, how much of inspiration for people who by listening to such a music are increasing nobility of their behaviour as well as their friendly approach to the Nature. - Many classical music works have been written with a strong inspiration by the Nature itself from the past until today. The actual Year of the Czech Music gives the possibility to present the most famous Czech composers inspired by the Nature (selected examples only): Bedřich Smetana (1824 - 1884): At the sea shore - a concert etude for piano inspired by his stay in Göteborg (Sweden); Vltava (Moldau) - a symphonic poem from the cycle "My country" inspired by the river crossing Bohemia from the South to Prague; From the Bohemian woods and meadows - another symphonic poem from the same cycle. Antonín Dvořák (1841 - 1904): V přírodě (In the Nature) - a work for orchestra Leoš Janáček (1854 - 1928): Příhody li\\vsky Bystrou\\vsky (The Cunning Little Vixen) - an opera situated mostly in a forest. Josef Bohuslav Foerster (1859-1951): Velké širé rodné lány (Big large native fields) - a choir for men singers inspired by the nature in the region where the composer as a boy from Prague was visiting his grand-father. Vítězslav Novák (1870 - 1949): In Tatra mountains - a symphonic poem expressing the author's passion for the famous

  3. COMPOSE-HPC: A Transformational Approach to Exascale

    SciTech Connect

    Bernholdt, David E; Allan, Benjamin A.; Armstrong, Robert C.; Chavarria-Miranda, Daniel; Dahlgren, Tamara L.; Elwasif, Wael R; Epperly, Tom; Foley, Samantha S; Hulette, Geoffrey C.; Krishnamoorthy, Sriram; Prantl, Adrian; Panyala, Ajay; Sottile, Matthew

    2012-04-01

    The goal of the COMPOSE-HPC project is to 'democratize' tools for automatic transformation of program source code so that it becomes tractable for the developers of scientific applications to create and use their own transformations reliably and safely. This paper describes our approach to this challenge, the creation of the KNOT tool chain, which includes tools for the creation of annotation languages to control the transformations (PAUL), to perform the transformations (ROTE), and optimization and code generation (BRAID), which can be used individually and in combination. We also provide examples of current and future uses of the KNOT tools, which include transforming code to use different programming models and environments, providing tests that can be used to detect errors in software or its execution, as well as composition of software written in different programming languages, or with different threading patterns.

  4. Exocytotic fusion pores are composed of both lipids and proteins

    PubMed Central

    Bao, Huan; Goldschen-Ohm, Marcel; Jeggle, Pia; Chanda, Baron; Edwardson, J Michael; Chapman, Edwin R

    2016-01-01

    During exocytosis, fusion pores form the first aqueous connection that allows escape of neurotransmitters and hormones from secretory vesicles. Although it is well established that SNARE proteins catalyze fusion, the structure and composition of fusion pores remain unknown. Here, we exploited the rigid framework and defined size of nanodiscs to interrogate the properties of reconstituted fusion pores, using the neurotransmitter glutamate as a content-mixing marker. Efficient Ca2+-stimulated bilayer fusion, and glutamate release, occurred with approximately two molecules of mouse synaptobrevin 2 reconstituted into ~6-nm nanodiscs. The transmembrane domains of SNARE proteins assumed distinct roles in lipid mixing versus content release and were exposed to polar solvent during fusion. Additionally, tryptophan substitutions at specific positions in these transmembrane domains decreased glutamate flux. Together, these findings indicate that the fusion pore is a hybrid structure composed of both lipids and proteins. PMID:26656855

  5. Nucleation of polyaniline nano-/macrotubes from anilinium composed micelles.

    PubMed

    Wang, Ruijuan; Wang, Chensen; Liu, Kong; Bei, Fengli; Lu, Lude; Han, Qiaofeng; Wu, Xiaodong

    2014-03-01

    A mechanistic study on the nucleation of polyaniline nanotubes (PANI-NT) through template-free method is explored by in situ solution-state (1)H NMR experiments via a careful analysis of the spectral evolution of the major species in the course of the reaction. Before polymerization, aniline and salicylic acid have assembled into loosely packed micelles due to electrostatic interactions and the proton exchange reaction between aniline and anilinium. A three-stage polymerization with a formation, accumulation of aniline dimers, as well as a generation of phenazine-like oligomers is observed, which can be attributed to the monomer transformation from neutral aniline molecules to anilinium cations and the significantly lowered pH in the reaction. Strong π-π stacking interactions from the phenazine-like oligomers facilitate the intermolecular aggregation which initiates the formation of PANI-NT. At first, such aggregates, locating at the outermost layer of anilinium composed micelles, shield in situ formed protons from releasing into the aqueous bulk but into the micelle instead. Due to the continuously increased charge in the micelle, a sphere-to-rod structural transition occurs which leads the oligomer aggregates to be sheathed at the exterior of the rod. Further consumption of anilinium in the micelle leaves the internal cavity while the fusion between the micelles elongates the length of the tubes. Our work demonstrates that (i) loosely packed anilinium composed micelles, highly mobile monomers within the micelle, and efficient blockage of the proton-releasing to the aqueous bulk are three key factors for the generation of tubular structures; and (ii) dynamic NMR line shape analysis provides a new perspective for resolving the formation profile of nanostructured polymers. PMID:24568544

  6. Reticulation des fibres lignocellulosiques

    NASA Astrophysics Data System (ADS)

    Landrevy, Christel

    Pour faire face à la crise économique la conception de papier à valeur ajoutée est développée par les industries papetières. Le but de se projet est l'amélioration des techniques actuelles de réticulation des fibres lignocellulosiques de la pâte à papier visant à produire un papier plus résistant. En effet, lors des réactions de réticulation traditionnelles, de nombreuses liaisons intra-fibres se forment ce qui affecte négativement l'amélioration anticipée des propriétés physiques du papier ou du matériau produit. Pour éviter la formation de ces liaisons intra-fibres, un greffage sur les fibres de groupements ne pouvant pas réagir entre eux est nécessaire. La réticulation des fibres par une réaction de « click chemistry » appelée cycloaddition de Huisgen entre un azide et un alcyne vrai, catalysée par du cuivre (CuAAC) a été l'une des solutions trouvée pour remédier à ce problème. De plus, une adaptation de cette réaction en milieux aqueux pourrait favoriser son utilisation en milieu industriel. L'étude que nous désirons entreprendre lors de ce projet vise à optimiser la réaction de CuAAC et les réactions intermédiaires (propargylation, tosylation et azidation) sur la pâte kraft, en milieu aqueux. Pour cela, les réactions ont été adaptées en milieu aqueux sur la cellulose microcristalline afin de vérifier sa faisabilité, puis transférée à la pâte kraft et l'influence de différents paramètres comme le temps de réaction ou la quantité de réactifs utilisée a été étudiée. Dans un second temps, une étude des différentes propriétés conférées au papier par les réactions a été réalisée à partir d'une série de tests papetiers optiques et physiques. Mots Clés Click chemistry, Huisgen, CuAAC, propargylation, tosylation, azidation, cellulose, pâte kraft, milieu aqueux, papier.

  7. Régimes transitoires des photopiles: durée de vie des porteurs et vitesse de recombinaison

    NASA Astrophysics Data System (ADS)

    Mialhe, P.; Sissoko, G.; Pelanchon, F.; Salagnon, J. M.

    1992-12-01

    A detailed analysis of a new experimental practice of the open circuit voltage decay method and of the short circuit current decay method for determining the base minority carrier lifetime and the back surface recombination velocity in solar cells has been performed. The measurements have been made by using the monitoring of a single transient of an operating cell at any level of injection; no power supply is required and a constant illumination level imposes the carrier injection level for normal operating conditions. The theory considers the complete continuity equation including generation and recombination rates of carriers. Precision and sensitivity of the method have been compared. The necessity of a precise knowledge of cell structural parameters have been shown to impose a limitation of the practical use of short-circuit current decay method, to low illumination levels. Cette étude développe une nouvelle méthode expérimentale pour mesurer la durée de vie des porteurs minoritaires dans la base d'une photopile ainsi que la vitesse de recombinaison à son interface arrière. Au cours de la mesure, la photopile est maintenue sous un éclairement constant qui impose le niveau d'injection souhaité. Cette méthode permet d'éliminer les effets néfastes à la mesure, provenant des impédances, propres au composant. Un régime transitoire, provoqué par une variation d'impédance, est étudié au cours de fonctionnements dans des conditions de court-circuit ou de circuit ouvert. L'étude théorique souligne la prise en compte de l'ensemble des phénomènes de recombinaison. L'obtention d'une bonne précision des mesures nécessite, avec une expérimentation rigoureuse, une connaissance précise des paramètres de structure de la photopile étudié. Pour la mesure de la durée de vie des porteurs, la plus grande sensibilité de la méthode en régime transitoire de court-circuit, comparée au régime de circuit ouvert, impose des mesures sous faible

  8. Coaxial nanocable composed by imogolite and carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Ramírez, M.; González, R. I.; Munoz, F.; Valdivia, J. A.; Rogan, J.; Kiwi, M.

    2015-12-01

    The discovery and development of Carbon Nanotubes (CNTs) at the beginning of the 1990s has driven a major part of solid state research. The electronic properties of the CNTs have generated a large number of ideas, as building coaxial nanocables. In this work we propose a possible type of such nanocables, which is formed by three nanostructures: two conducting CNTs, where one of them is covered by an insulator (an inorganic oxide nanotube: the imogolite aluminosilicate). The theoretical calculations were carried out using the density functional tight-binding formalism, by means of the DFTB+ code. This formalism allows to calculate the band structure, which compares favorably with DFT calculations, but with a significantly lower computational cost. As a first step, we reproduce the calculations of already published results, where the formation of a nanocable composed by one CNT and the imogolite as an insulator. Afterwards, we simulate the band structure for the proposed structure to study the feasibility of the coaxial nanocable. Finally, using classical MD simulations, we study the possible mechanisms of formation of these nanocables.

  9. Percolation in networks composed of connectivity and dependency links

    NASA Astrophysics Data System (ADS)

    Bashan, Amir; Parshani, Roni; Havlin, Shlomo

    2011-05-01

    Networks composed from both connectivity and dependency links were found to be more vulnerable compared to classical networks with only connectivity links. Their percolation transition is usually of a first order compared to the second-order transition found in classical networks. We analytically analyze the effect of different distributions of dependencies links on the robustness of networks. For a random Erdös-Rényi (ER) network with average degree k that is divided into dependency clusters of size s, the fraction of nodes that belong to the giant component P∞ is given by P∞=ps-1[1-exp(-kpP∞)]s, where 1-p is the initial fraction of removed nodes. Our general result coincides with the known Erdös-Rényi equation for random networks for s=1. For networks with Poissonian distribution of dependency links we find that P∞ is given by P∞=fk,p(P∞)e(-1)[pfk,p(P∞)-1], where fk,p(P∞)≡1-exp(-kpP∞) and is the mean value of the size of dependency clusters. For networks with Gaussian distribution of dependency links we show how the average and width of the distribution affect the robustness of the networks.

  10. [Alexander Borodin--physician, chemist, scientist, teacher and composer].

    PubMed

    Vik, T

    1998-12-10

    Concert programmes and CD covers suggest that the Russian composer Alexander Borodin (1833-87) was also a great scientist. In this article we examine this proposition. Borodin was born in St. Petersburg as the illegitimate son of a Russian nobleman. As a boy his talents ranged from music to chemistry and languages. Borodin studied medicine at the Medico-Surgical Academy in St. Petersburg from 1850 to 1855 and defended his doctoral thesis on the similarity between arsenic and phosphoric acid in 1858. He did not, however, feel comfortable in his role as a doctor, and soon started to work as a chemist. In 1864 he was appointed professor of chemistry at the Medico-Surgical Academy. In 1861, Borodin attended the first international congress of chemistry in Karlsruhe, and he was among the founders of the Russian Chemical Society in 1868. He published 42 articles and was a friend of Dmitri Mendeleev, the scientist who described the periodic system. In 1872, Borodin started the first medical courses for women in Russia. It seems warranted to conclude that Alexander Borodin was indeed a great scientist and university teacher, though his immortality was earned by his leisure time activities. PMID:9914755

  11. Hierarchical spatial heterogeneity in liquid crystals composed of graphene oxides.

    PubMed

    Shundo, Atsuomi; Hori, Koichiro; Penaloza, David P; Matsumoto, Yuji; Okumura, Yasushi; Kikuchi, Hirotsugu; Lee, Kyung Eun; Kim, Sang Ouk; Tanaka, Keiji

    2016-08-10

    Graphene oxide (GO) is a class of two-dimensional materials with a thickness of about 1 nm and a broad distribution of lateral dimension commonly approaching several micrometers. A dispersion of GOs in water often forms a liquid crystal, which is expected to be a promising precursor for the fabrication of carbon-based materials with well-ordered structures. To accelerate the application of GO-based liquid crystals, their structures and physical properties at various sizes must be well understood. To that end, we examined the local rheological properties of GO-based liquid crystals in the nematic phase using a particle tracking technique, where local properties can be accessed by observing the thermal motion of embedded probe particles. Particle diffusion was spatially heterogeneous, and depended on the size of the particles. Such a size-dependent heterogeneity can be associated with a hierarchical local environment, which is time-dependent for this system. The anisotropic particle diffusion originated from particles trapped in between the GO layers and in isotropic-like regions. The aggregation states of the GO dispersion composed of nematic and isotropic-like regions were observed using confocal laser scanning microscopy. PMID:27464002

  12. FIA: An Open Forensic Integration Architecture for Composing Digital Evidence

    NASA Astrophysics Data System (ADS)

    Raghavan, Sriram; Clark, Andrew; Mohay, George

    The analysis and value of digital evidence in an investigation has been the domain of discourse in the digital forensic community for several years. While many works have considered different approaches to model digital evidence, a comprehensive understanding of the process of merging different evidence items recovered during a forensic analysis is still a distant dream. With the advent of modern technologies, pro-active measures are integral to keeping abreast of all forms of cyber crimes and attacks. This paper motivates the need to formalize the process of analyzing digital evidence from multiple sources simultaneously. In this paper, we present the forensic integration architecture (FIA) which provides a framework for abstracting the evidence source and storage format information from digital evidence and explores the concept of integrating evidence information from multiple sources. The FIA architecture identifies evidence information from multiple sources that enables an investigator to build theories to reconstruct the past. FIA is hierarchically composed of multiple layers and adopts a technology independent approach. FIA is also open and extensible making it simple to adapt to technological changes. We present a case study using a hypothetical car theft case to demonstrate the concepts and illustrate the value it brings into the field.

  13. Rheology of granular materials composed of nonconvex particles

    NASA Astrophysics Data System (ADS)

    Saint-Cyr, B.; Delenne, J.-Y.; Voivret, C.; Radjai, F.; Sornay, P.

    2011-10-01

    By means of contact dynamics simulations, we investigate the shear strength and internal structure of granular materials composed of two-dimensional nonconvex aggregates. We find that the packing fraction first grows as the nonconvexity is increased but declines at higher nonconvexity. This unmonotonic dependence reflects the competing effects of pore size reduction between convex borders of aggregates and gain in porosity at the nonconvex borders that are captured in a simple model fitting nicely the simulation data both in the isotropic and sheared packings. On the other hand, the internal angle of friction increases linearly with nonconvexity and saturates to a value independent of nonconvexity. We show that fabric anisotropy, force anisotropy, and friction mobilization, all enhanced by multiple contacts between aggregates, govern the observed increase of shear strength and its saturation with increasing nonconvexity. The main effect of interlocking is to dislocate frictional dissipation from the locked double and triple contacts between aggregates to the simple contacts between clusters of aggregates. This self-organization of particle motions allows the packing to keep a constant shear strength at high nonconvexity.

  14. Composable Analytic Systems for next-generation intelligence analysis

    NASA Astrophysics Data System (ADS)

    DiBona, Phil; Llinas, James; Barry, Kevin

    2015-05-01

    Lockheed Martin Advanced Technology Laboratories (LM ATL) is collaborating with Professor James Llinas, Ph.D., of the Center for Multisource Information Fusion at the University at Buffalo (State of NY), researching concepts for a mixed-initiative associate system for intelligence analysts to facilitate reduced analysis and decision times while proactively discovering and presenting relevant information based on the analyst's needs, current tasks and cognitive state. Today's exploitation and analysis systems have largely been designed for a specific sensor, data type, and operational context, leading to difficulty in directly supporting the analyst's evolving tasking and work product development preferences across complex Operational Environments. Our interactions with analysts illuminate the need to impact the information fusion, exploitation, and analysis capabilities in a variety of ways, including understanding data options, algorithm composition, hypothesis validation, and work product development. Composable Analytic Systems, an analyst-driven system that increases flexibility and capability to effectively utilize Multi-INT fusion and analytics tailored to the analyst's mission needs, holds promise to addresses the current and future intelligence analysis needs, as US forces engage threats in contested and denied environments.

  15. Coaxial nanocable composed by imogolite and carbon nanotubes

    SciTech Connect

    Ramírez, M.; González, R. I.; Munoz, F.; Valdivia, J. A.; Rogan, J.; Kiwi, M.

    2015-12-31

    The discovery and development of Carbon Nanotubes (CNTs) at the beginning of the 1990s has driven a major part of solid state research. The electronic properties of the CNTs have generated a large number of ideas, as building coaxial nanocables. In this work we propose a possible type of such nanocables, which is formed by three nanostructures: two conducting CNTs, where one of them is covered by an insulator (an inorganic oxide nanotube: the imogolite aluminosilicate). The theoretical calculations were carried out using the density functional tight-binding formalism, by means of the DFTB+ code. This formalism allows to calculate the band structure, which compares favorably with DFT calculations, but with a significantly lower computational cost. As a first step, we reproduce the calculations of already published results, where the formation of a nanocable composed by one CNT and the imogolite as an insulator. Afterwards, we simulate the band structure for the proposed structure to study the feasibility of the coaxial nanocable. Finally, using classical MD simulations, we study the possible mechanisms of formation of these nanocables.

  16. Chondroinductive Hydrogel Pastes Composed of Naturally Derived Devitalized Cartilage.

    PubMed

    Beck, Emily C; Barragan, Marilyn; Tadros, Madeleine H; Kiyotake, Emi A; Acosta, Francisca M; Kieweg, Sarah L; Detamore, Michael S

    2016-06-01

    Hydrogel precursors are liquid solutions that are prone to leaking from the defect site once implanted in vivo. Therefore, the objective of the current study was to create a hydrogel precursor that exhibited a yield stress. Additionally, devitalized cartilage extracellular matrix (DVC) was mixed with DVC that had been solubilized and methacrylated (MeSDVC) to create hydrogels that were chondroinductive. Precursors composed of 10% MeSDVC or 10% MeSDVC with 10% DVC were first evaluated rheologically, where non-Newtonian behavior was observed in all hydrogel precursors. Rat bone marrow stem cells (rBMSCs) were mixed in the precursor solutions, and the solutions were then crosslinked and cultured in vitro for 6 weeks with and without exposure to human transforming growth factor β3 (TGF-β3). The compressive modulus, gene expression, biochemical content, swelling, and histology of the gels were analyzed. The DVC-containing gels consistently outperformed the MeSDVC-only group in chondrogenic gene expression, especially at 6 weeks, where the relative collagen II expression of the DVC-containing groups with and without TGF-β3 exposure was 40- and 78-fold higher, respectively, than that of MeSDVC alone. Future work will test for chondrogenesis in vivo and overall, these two cartilage-derived components are promising materials for cartilage tissue engineering applications. PMID:26744243

  17. Composable languages for bioinformatics: the NYoSh experiment.

    PubMed

    Simi, Manuele; Campagne, Fabien

    2014-01-01

    Language WorkBenches (LWBs) are software engineering tools that help domain experts develop solutions to various classes of problems. Some of these tools focus on non-technical users and provide languages to help organize knowledge while other workbenches provide means to create new programming languages. A key advantage of language workbenches is that they support the seamless composition of independently developed languages. This capability is useful when developing programs that can benefit from different levels of abstraction. We reasoned that language workbenches could be useful to develop bioinformatics software solutions. In order to evaluate the potential of language workbenches in bioinformatics, we tested a prominent workbench by developing an alternative to shell scripting. To illustrate what LWBs and Language Composition can bring to bioinformatics, we report on our design and development of NYoSh (Not Your ordinary Shell). NYoSh was implemented as a collection of languages that can be composed to write programs as expressive and concise as shell scripts. This manuscript offers a concrete illustration of the advantages and current minor drawbacks of using the MPS LWB. For instance, we found that we could implement an environment-aware editor for NYoSh that can assist the programmers when developing scripts for specific execution environments. This editor further provides semantic error detection and can be compiled interactively with an automatic build and deployment system. In contrast to shell scripts, NYoSh scripts can be written in a modern development environment, supporting context dependent intentions and can be extended seamlessly by end-users with new abstractions and language constructs. We further illustrate language extension and composition with LWBs by presenting a tight integration of NYoSh scripts with the GobyWeb system. The NYoSh Workbench prototype, which implements a fully featured integrated development environment for NYoSh is

  18. Composable languages for bioinformatics: the NYoSh experiment

    PubMed Central

    Simi, Manuele

    2014-01-01

    Language WorkBenches (LWBs) are software engineering tools that help domain experts develop solutions to various classes of problems. Some of these tools focus on non-technical users and provide languages to help organize knowledge while other workbenches provide means to create new programming languages. A key advantage of language workbenches is that they support the seamless composition of independently developed languages. This capability is useful when developing programs that can benefit from different levels of abstraction. We reasoned that language workbenches could be useful to develop bioinformatics software solutions. In order to evaluate the potential of language workbenches in bioinformatics, we tested a prominent workbench by developing an alternative to shell scripting. To illustrate what LWBs and Language Composition can bring to bioinformatics, we report on our design and development of NYoSh (Not Your ordinary Shell). NYoSh was implemented as a collection of languages that can be composed to write programs as expressive and concise as shell scripts. This manuscript offers a concrete illustration of the advantages and current minor drawbacks of using the MPS LWB. For instance, we found that we could implement an environment-aware editor for NYoSh that can assist the programmers when developing scripts for specific execution environments. This editor further provides semantic error detection and can be compiled interactively with an automatic build and deployment system. In contrast to shell scripts, NYoSh scripts can be written in a modern development environment, supporting context dependent intentions and can be extended seamlessly by end-users with new abstractions and language constructs. We further illustrate language extension and composition with LWBs by presenting a tight integration of NYoSh scripts with the GobyWeb system. The NYoSh Workbench prototype, which implements a fully featured integrated development environment for NYoSh is

  19. Electrochemical machining analysis on grid cathode composed of square cells

    NASA Astrophysics Data System (ADS)

    Lu, Yonghua; Liu, Kai; Zhao, Dongbiao

    2013-07-01

    During the electrochemical machining (ECM), the cathodes designed by the existing methods are mainly unitary cathodes, which can be only used to produce the workpieces with the same shapes. However, there are few researches on designing cathodes for machining the different workpieces with the different surfaces. This paper presents the grid cathode composed of the square cells to produce the workpieces with different shapes. Three types of the square cells, 2.5 mm×2.5 mm, 3 mm×3 mm, and 4 mm×4 mm, are utilized to construct the plane, the slant, and the blade cathode. The material of the cathode and the anode is CrNi18Ti9, and the ingredient of electrolyte is 15% NaCl and 15% NaNO3. The machining equilibrium machining current and time are acquired and analyzed, the machining process and the workpiece quality are compared between using the grid cathode and the unitary cathode. Moreover, the machining errors on the workpiece surface are measured and analyzed, and the error reasons are traced and discussed to obtain the better surface quality of the workpiece. The experiment and analysis results show that the grid cathode can be used to manufacture the workpieces with complex shapes in certain range of the error. The workpiece quality improves with the size of the square cell being reduced, and if the square element is small enough, the workpiece quality is almost equal to the one machined by the unitary cathode. The proposed research realizes a single cathode machining the different workpieces with the different surfaces.

  20. Médecine des voyages

    PubMed Central

    Aw, Brian; Boraston, Suni; Botten, David; Cherniwchan, Darin; Fazal, Hyder; Kelton, Timothy; Libman, Michael; Saldanha, Colin; Scappatura, Philip; Stowe, Brian

    2014-01-01

    Résumé Objectif Définir la pratique de la médecine des voyages, présenter les éléments fondamentaux d’une consultation complète préalable aux voyages à des voyageurs internationaux et aider à identifier les patients qu’il vaudrait mieux envoyer en consultation auprès de professionnels de la médecine des voyages. Sources des données Les lignes directrices et les recommandations sur la médecine des voyages et les maladies liées aux voyages publiées par les autorités sanitaires nationales et internationales ont fait l’objet d’un examen. Une recension des ouvrages connexes dans MEDLINE et EMBASE a aussi été effectuée. Message principal La médecine des voyages est une spécialité très dynamique qui se concentre sur les soins préventifs avant un voyage. Une évaluation exhaustive du risque pour chaque voyageur est essentielle pour mesurer avec exactitude les risques particuliers au voyageur, à son itinéraire et à sa destination et pour offrir des conseils sur les interventions les plus appropriées en gestion du risque afin de promouvoir la santé et prévenir les problèmes médicaux indésirables durant le voyage. Des vaccins peuvent aussi être nécessaires et doivent être personnalisés en fonction des antécédents d’immunisation du voyageur, de son itinéraire et du temps qu’il reste avant son départ. Conclusion La santé et la sécurité d’un voyageur dépendent du degré d’expertise du médecin qui offre le counseling préalable à son voyage et les vaccins, au besoin. On recommande à ceux qui donnent des conseils aux voyageurs d’être conscients de l’ampleur de cette responsabilité et de demander si possible une consultation auprès de professionnels de la médecine des voyages pour tous les voyageurs à risque élevé.

  1. NERIES: Seismic Data Gateways and User Composed Datasets Metadata Management

    NASA Astrophysics Data System (ADS)

    Spinuso, Alessandro; Trani, Luca; Kamb, Linus; Frobert, Laurent

    2010-05-01

    One of the NERIES EC project main objectives is to establish and improve the networking of seismic waveform data exchange and access among four main data centers in Europe: INGV, GFZ, ORFEUS and IPGP. Besides the implementation of the data backbone, several investigations and developments have been conducted in order to offer to the users the data available from this network, either programmatically or interactively. One of the challenges is to understand how to enable users` activities such as discovering, aggregating, describing and sharing datasets to obtain a decrease in the replication of similar data queries towards the network, exempting the data centers to guess and create useful pre-packed products. We`ve started to transfer this task more and more towards the users community, where the users` composed data products could be extensively re-used. The main link to the data is represented by a centralized webservice (SeismoLink) acting like a single access point to the whole data network. Users can download either waveform data or seismic station inventories directly from their own software routines by connecting to this webservice, which routes the request to the data centers. The provenance of the data is maintained and transferred to the users in the form of URIs, that identify the dataset and implicitly refer to the data provider. SeismoLink, combined with other webservices (eg EMSC-QuakeML earthquakes catalog service), is used from a community gateway such as the NERIES web portal (http://www.seismicportal.eu). Here the user interacts with a map based portlet which allows the dynamic composition of a data product, binding seismic event`s parameters with a set of seismic stations. The requested data is collected by the back-end processes of the portal, preserved and offered to the user in a personal data cart, where metadata can be generated interactively on-demand. The metadata, expressed in RDF, can also be remotely ingested. They offer rating

  2. Towards a Dynamic DES model

    NASA Astrophysics Data System (ADS)

    Subbareddy, Pramod; Candler, Graham

    2009-11-01

    Hybrid RANS/LES methods are being increasingly used for turbulent flow simulations in complex geometries. Spalart's detached eddy simulation (DES) model is one of the more popular ones. We are interested in examining the behavior of the Spalart-Allmaras (S-A) Detached Eddy Simulation (DES) model in its ``LES mode.'' The role of the near-wall functions present in the equations is analyzed and an explicit analogy between the S-A and a one-equation LES model based on the sub-grid kinetic energy is presented. A dynamic version of the S-A DES model is proposed based on this connection. Validation studies and results from DES and LES applications will be presented and the effect of the proposed modification will be discussed.

  3. Principles of moment distribution applied to stability of structures composed of bars or plates

    NASA Technical Reports Server (NTRS)

    Lundquist, Eugene E; Stowell, Elbridge Z; Schuette, Evan H

    1943-01-01

    Principles of the cross method of moment distribution, which have previously been applied to the stability of structures composed of bars under axial load, are applied to the stability of structures composed of long plates under longitudinal load.

  4. Vecteurs Singuliers des Theories des Champs Conformes Minimales

    NASA Astrophysics Data System (ADS)

    Benoit, Louis

    En 1984 Belavin, Polyakov et Zamolodchikov revolutionnent la theorie des champs en explicitant une nouvelle gamme de theories, les theories quantiques des champs bidimensionnelles invariantes sous les transformations conformes. L'algebre des transformations conformes de l'espace-temps presente une caracteristique remarquable: en deux dimensions elle possede un nombre infini de generateurs. Cette propriete impose de telles conditions aux fonctions de correlations qu'il est possible de les evaluer sans aucune approximation. Les champs des theories conformes appartiennent a des representations de plus haut poids de l'algebre de Virasoro, une extension centrale de l'algebre conforme du plan. Ces representations sont etiquetees par h, le poids conforme de leur vecteur de plus haut poids, et par la charge centrale c, le facteur de l'extension centrale, commune a toutes les representations d'une meme theorie. Les theories conformes minimales sont constituees d'un nombre fini de representations. Parmi celles-ci se trouvent des theories unitaires dont les representation forment la serie discrete de l'algebre de Virasoro; leur poids h a la forme h_{p,q}(m)=[ (p(m+1) -qm)^2-1] (4m(m+1)), ou p,q et m sont des entiers positifs et p+q<= m+1. L'entier m parametrise la charge centrale: c(m)=1 -{6over m(m+1)} avec n>= 2. Ces representations possedent un sous-espace invariant engendre par deux sous-representations avec h_1=h_{p,q} + pq et h_2=h_{p,q} + (m-p)(m+1-q) dont chacun des vecteurs de plus haut poids portent le nom de vecteur singulier et sont notes respectivement |Psi _{p,q}> et |Psi_{m-p,m+1-q}>. . Les theories super-conformes sont une version super-symetrique des theories conformes. Leurs champs appartiennent a des representation de plus haut poids de l'algebre de Neveu-Schwarz, une des deux extensions super -symetriques de l'algebre de Virasoro. Les theories super -conformes minimales possedent la meme structure que les theories conformes minimales. Les representations

  5. The Movement of Air, the Breath of Meaning: Aurality and Multimodal Composing

    ERIC Educational Resources Information Center

    Selfe, Cynthia L.

    2009-01-01

    Rhetoric and composition's increasing attention to multimodal composing involves challenges that go beyond issues of access to digital technologies and electronic composing environments. As a specific case study, this article explores the history of aural composing modalities (speech, music, sound) and examines how they have been understood and…

  6. Writing in an Electronic Age: A Case Study of L2 Composing Processes

    ERIC Educational Resources Information Center

    Stapleton, Paul

    2010-01-01

    Studies on second language (L2) learners writing in English have found that composing is a recursive process requiring planning, formulating and revising. Of particular note among the many studies that have explored the composing processes of L2 writers are two characteristics: 1) They examine the composing processes of writers in real-time while…

  7. Rethinking Joseph Janangelo's "Joseph Cornell and the Artistry of Composing Persuasive Hypertexts"

    ERIC Educational Resources Information Center

    College Composition and Communication, 2007

    2007-01-01

    This article presents several excerpts from an article written by Joseph Janangelo titled "Joseph Cornell and the Artistry of Composing Persuasive Hypertexts." In his article, Janangelo suggested that Cornell's work and ideas about composing model intelligent ways to composing persuasive nonsequential text. Janangelo also wondered if the use of…

  8. Caractérisation électrique des interfaces P^+ - Si - poly/N-c-Si réalisées par dépôt LPCVD de films fortement dopés in situ au bore

    NASA Astrophysics Data System (ADS)

    Akani, M.; Benouis, C. E.; Benzohra, M.

    1993-11-01

    La liste des auteurs (et leur adresse) concernant cet article sont à corriger comme suit: The list of authors (and the address) for this article are to be corrected as follows: M. Idrissi-Benzohra, M. Akani, C. E. Benouis, M. Benzohra Laboratoire d'Analyse des Composants au Silcium, Université des Sciences et de la Technologie d'Oran, Oran El-Mnaouer 31000, Algérie.

  9. Sheet music by mind: Towards a brain-computer interface for composing.

    PubMed

    Pinegger, Andreas; Wriessnegger, Selina C; Muller-Putz, Gernot R

    2015-08-01

    Providing brain-computer interface (BCI) users engaging applications should be one of the main targets in BCI research. A painting application, a web browser and other applications can already be controlled via BCI. Another engaging application would be a music composer for self-expression. In this work, we describe Brain Composing: A BCI controlled music composing software. We tested and evaluated the implemented brain composing system with five volunteers. Using a tap water-based electrode biosignal amplifier further improved the usability of the system. Three participants reached accuracies above 77% and were able to copy-compose a given melody. Results of questionnaires support that our brain composing system is an attractive and easy way to compose music via a BCI. PMID:26736446

  10. Peste des petits ruminants

    PubMed Central

    Parida, S.; Muniraju, M.; Mahapatra, M.; Muthuchelvan, D.; Buczkowski, H.; Banyard, A.C.

    2015-01-01

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants. PMID:26443889

  11. The Brain Functional State of Music Creation: an fMRI Study of Composers.

    PubMed

    Lu, Jing; Yang, Hua; Zhang, Xingxing; He, Hui; Luo, Cheng; Yao, Dezhong

    2015-01-01

    In this study, we used functional magnetic resonance imaging (fMRI) to explore the functional networks in professional composers during the creation of music. We compared the composing state and resting state imagery of 17 composers and found that the functional connectivity of primary networks in the bilateral occipital lobe and bilateral postcentral cortex decreased during the composing period. However, significantly stronger functional connectivity appeared between the anterior cingulate cortex (ACC), the right angular gyrus and the bilateral superior frontal gyrus during composition. These findings indicate that a specific brain state of musical creation is formed when professional composers are composing, in which the integration of the primary visual and motor areas is not necessary. Instead, the neurons of these areas are recruited to enhance the functional connectivity between the ACC and the default mode network (DMN) to plan the integration of musical notes with emotion. PMID:26203921

  12. The Brain Functional State of Music Creation: an fMRI Study of Composers

    PubMed Central

    Lu, Jing; Yang, Hua; Zhang, Xingxing; He, Hui; Luo, Cheng; Yao, Dezhong

    2015-01-01

    In this study, we used functional magnetic resonance imaging (fMRI) to explore the functional networks in professional composers during the creation of music. We compared the composing state and resting state imagery of 17 composers and found that the functional connectivity of primary networks in the bilateral occipital lobe and bilateral postcentral cortex decreased during the composing period. However, significantly stronger functional connectivity appeared between the anterior cingulate cortex (ACC), the right angular gyrus and the bilateral superior frontal gyrus during composition. These findings indicate that a specific brain state of musical creation is formed when professional composers are composing, in which the integration of the primary visual and motor areas is not necessary. Instead, the neurons of these areas are recruited to enhance the functional connectivity between the ACC and the default mode network (DMN) to plan the integration of musical notes with emotion. PMID:26203921

  13. Classification of 20 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Davis, T. M.; Kim, A. G.; Macualay, E.; Lidman, C.; Sharp, R.; Tucker, B. E.; Yuan, F.; Zhang, B.; Lewis, G. F.; Sommer, N. E.; Martini, P.; Mould, J.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  14. Classification of 15 DES supernovae by OzDES

    NASA Astrophysics Data System (ADS)

    Yuan, F.; Tucker, B. E.; Lidman, C.; Martini, P.; Gshwend, Julia; Moller, A.; Zhang, B.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  15. Classification of 3 DES Supernovae with OzDES

    NASA Astrophysics Data System (ADS)

    Moller, A.; Tucker, B. E.; Yuan, F.; Lewis, G.; Lidman, C.; Macaulay, E.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.

    2016-02-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  16. Classification of 4 DES supernovae by OzDES

    NASA Astrophysics Data System (ADS)

    Glazebrook, K.; Amon, A.; Lidman, C.; Martini, P.; Tucker, B. E.; Yuan, F.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  17. Classification of 6 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Lewis, G. F.; Mould, J.; Lidman, C.; Tucker, B. E.; Sharp, R.; Yuan, F.; Martini, P.; Kessler, R.; Scolnic, D.; Covarrubias, R. A.; Brout, D. J.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Smith, M.; Sullivan, M.; Childress, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.

    2015-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  18. Classification of 14 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Tucker, B. E.; Sharp, R.; Yuan, F.; Zhang, B.; Lidman, C.; Davis, T. M.; Hinton, S.; Mould, J.; Smith, R. C.; Schubnell, M.; Kessler, R.; Scolnic, D.; Covarrubias, R. A.; Brout, D. J.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Smith, M.; Sullivan, M.; Childress, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Castander, F. J.; Desai, S.; Paech, K.

    2015-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey. The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  19. Composing Science

    NASA Astrophysics Data System (ADS)

    Atkins, Leslie

    2015-03-01

    The course Scientific Inquiry at California State University was developed by faculty in biology, physics and English to meet ``writing proficiency'' requirements for non-science majors. Drawing from previous work in composition studies, the position that we take in this course is that we should be engaging students in writing that replicates the work that writing does in science, rather than replicating the particular structural conventions characteristic of scientific writing. That is, scientists use writing to have, remember, share, vet, challenge, and stabilize ideas, and our course requires students use writing to achieve those aims, rather than produce writing that obeys particular conventions of scientific writing. This talk will describe how we have integrated findings from composition studies with a course on scientific inquiry, and provide examples of how scientific communication has resulted from this dialogue. Funding by NSF #1140860.

  20. 16 CFR 300.29 - Garments or products composed of or containing miscellaneous cloth scraps.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .... (2) Where the product contains chiefly rayon as well as woolen fibers in the minimum percentage designated for recycled wool: Made of Miscellaneous Cloth Scraps Composed Chiefly of Rayon With Minimum of __% Recycled Wool. (3) Where the product is composed chiefly of a mixture of cotton and rayon as well as...

  1. 16 CFR 300.29 - Garments or products composed of or containing miscellaneous cloth scraps.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... (2) Where the product contains chiefly rayon as well as woolen fibers in the minimum percentage designated for recycled wool: Made of Miscellaneous Cloth Scraps Composed Chiefly of Rayon With Minimum of __% Recycled Wool. (3) Where the product is composed chiefly of a mixture of cotton and rayon as well as...

  2. 16 CFR 300.29 - Garments or products composed of or containing miscellaneous cloth scraps.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    .... (2) Where the product contains chiefly rayon as well as woolen fibers in the minimum percentage designated for recycled wool: Made of Miscellaneous Cloth Scraps Composed Chiefly of Rayon With Minimum of __% Recycled Wool. (3) Where the product is composed chiefly of a mixture of cotton and rayon as well as...

  3. 16 CFR 300.29 - Garments or products composed of or containing miscellaneous cloth scraps.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    .... (2) Where the product contains chiefly rayon as well as woolen fibers in the minimum percentage designated for recycled wool: Made of Miscellaneous Cloth Scraps Composed Chiefly of Rayon With Minimum of __% Recycled Wool. (3) Where the product is composed chiefly of a mixture of cotton and rayon as well as...

  4. 16 CFR 300.29 - Garments or products composed of or containing miscellaneous cloth scraps.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    .... (2) Where the product contains chiefly rayon as well as woolen fibers in the minimum percentage designated for recycled wool: Made of Miscellaneous Cloth Scraps Composed Chiefly of Rayon With Minimum of __% Recycled Wool. (3) Where the product is composed chiefly of a mixture of cotton and rayon as well as...

  5. Rethinking Composing in a Digital Age: Authoring Literate Identities through Multimodal Storytelling

    ERIC Educational Resources Information Center

    Vasudevan, Lalitha; Schultz, Katherine; Bateman, Jennifer

    2010-01-01

    In this article, the authors engage the theoretical lens of multimodality in rethinking the practices and processes of composing in classrooms. Specifically, they focus on how learning new composing practices led some fifth-grade students to author new literate identities--what they call authorial stances--in their classroom community. Their…

  6. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  7. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  8. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  9. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  10. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  11. Making Judgements: Investigating the Process of Composing and Receiving Peer Feedback

    ERIC Educational Resources Information Center

    McConlogue, Teresa

    2015-01-01

    Recent studies have argued that tutor feedback is failing to support students' progression. The potential for peer feedback, i.e. feedback composed by peer assessors, to support learning has been under researched. The aim of this paper was to explore a case study of a peer assessor composing and receiving peer feedback. The paper reports a case…

  12. Transforming Experience: Negotiations of Sexual Identity in the Composing Processes of Gay Men

    ERIC Educational Resources Information Center

    Berry, William F.

    2012-01-01

    Negotiating meaning, knowledge, and identity is fundamental to composing processes. These negotiations occur both individually and socially for writers. Sexual identity is an intrinsic part of these negotiations, but is often overlooked by researchers. This study explored the phenomenon of negotiating sexual identity in the composing processes of…

  13. Composing with an Eye to the Unexpected: An Interview with John Heiss.

    ERIC Educational Resources Information Center

    Jordan, Helen Bohn

    1984-01-01

    John Heiss, a teacher and composer, describes how he came to write "Songs of Nature," a song cycle with text by nineteenth-century American poets. Heiss believes that, though a composer must know his craft, there should be room for intuition and the emotions in the creative process. (CS)

  14. Multimodal Composing in Classrooms: Learning and Teaching for the Digital World

    ERIC Educational Resources Information Center

    Miller, Suzanne M., Ed.; McVee, Mary B., Ed.

    2012-01-01

    Taking a close look at multimodal composing as an essential new literacy in schools, this volume draws from contextualized case studies across educational contexts to provide detailed portraits of teachers and students at work in classrooms. Authors elaborate key issues in transforming classrooms with student multimodal composing, including…

  15. Annuaire du Bureau des longitudes - 2006

    NASA Astrophysics Data System (ADS)

    Imcce; Bureau Des Longitudes

    2005-07-01

    This annual publication provides ephemerides and data to the use of professionnal and amateur astronomers. Divided in 11 chapters it covers concordance of various calendars, explanation of fondamental astronomy and various time scales, explanation for the use of ephemerides; tables provide ephemerides (positions, rise/set/passage) of the Sun and the Moon, planets, planetary satellites, asteroids, comets, bright stars; data and explanation for the physical observation of the surface of the Sun, the Moon, and planets; chart of the sky and a list of constellations and galaxies; prediction and ephemerides for astronomical phenomenon: occultation by the moon, stellar occultations by asteroids and appulses, solar eclipses and lunar eclipses; and an additional review about a hot scientific topic, this year: "Legendre et le méridien terrestre, 200 ans après". Cette publication annuelle fournit des éphémérides et des données à l'usage des astronomes professionnels et des astronomes amateurs. Composée de 11 chapitres elle comprend les rubriques sur les différents calendriers et leurs concordance, les fêtes légales en France, les dates et décrets sur les heures légales en France métropolitaine ; une introduction à l'astronomie fondamentale et aux différentes échelles de temps, des explications sur l'utilisation des éphémérides ; des tables fournissent les éphémérides (positions, heures de lever/coucher/passage) du Soleil et de la Lune, de planètes, de satellites naturels, d'astéroïdes, de comètes, d'étoiles brillantes ; des données pour l'observation de la surface du Soleil, de la Lune, et des planètes ; des cartes du ciel ainsi qu'une liste de constellations et de galaxies ; des prédictions des phénomènes astronomiques : occultation par la Lune, occultation stellaires par des astéroïdes et appulses, éclipses de Soleil et de la Lune; la liste et les coordonnées des observatoires astronomiques les plus connus ; et enfin un cahier th

  16. Twenty-Five Years of Scholarship on Second Language Composing Processes: 1976-2000.

    ERIC Educational Resources Information Center

    Silva, Tony; Kapper, Jessie; Brice, Colleen; Matsuda, Paul Kei; Reichelt, Melinda

    2001-01-01

    This bibliography includes both an annotated and unannotated section on research conducted on second language composing processes in the last 25 years. It includes both published and unpublished material. (Author/VWL)

  17. Optimum Running Condition of Honeycomb Type Rotation Desiccant Device Composed of Polymer Sorbent

    NASA Astrophysics Data System (ADS)

    Kida, Takahisa; Inaba, Hideo; Horibe, Akihiko

    This paper deals with the optimum running conditions of honeycomb rotor composed of new polymer sorbent which was composed of the cross-linked polymer of sodium acrylate. At first, overall mass transfer coefficient of the honeycomb rotor for numerical computation was derived by the experimental results from the model experimental apparatus. Numerical simulations could predict the optimum running conditions of the honeycomb rotor such as the revolution number of the honeycomb rotor against the inflow air velocity and honeycomb length etc.

  18. In fatal pursuit of immortal fame: Peer competition and early mortality of music composers.

    PubMed

    Borowiecki, Karol Jan; Kavetsos, Georgios

    2015-06-01

    We investigate the impact of peer competition on longevity using a unique historical data set of 144 prominent music composers born in the 19th century. We approximate for peer competition measuring (a) the number or (b) the share of composers located in the same area and time, (c) the time spent in one of the main cities for classical music, and (d) the quality of fellow composers. These measures suggest that composers' longevity is reduced, if they located in agglomerations with a larger group of peers or of a higher quality. The point estimates imply that, all else equal, a one percent increase in the number of composers reduces composer longevity by ∼ 7.2 weeks. Our analysis showed that the utilized concentration measures are stronger than the personal factors in determining longevity, indicating that individuals' backgrounds have minimal impact on mitigating the effect of experienced peer pressure. The negative externality of peer competition is experienced in all cities, fairly independent of their population size. Our results are reaffirmed using an instrumental variable approach and are consistent throughout a range of robustness tests. In addition to the widely known economic benefits associated with competition, these findings suggest that significant negative welfare externalities exist as well. PMID:25880825

  19. Transport quantique dans des nanostructures

    NASA Astrophysics Data System (ADS)

    Naud, C.

    2002-09-01

    structure des oscillations de conductance en fonction du flux du champ magnétique de période h/e dont l'amplitude est beaucoup plus importante que celle mesurée sur un réseau carré de même dimension. Cette différence constitue une signature d'un effet de localisation induit par le champ magnétique sur la topologie mathcal{T}3. Pour des valeurs spécifiques du champ magnétique, du fait des interférences destructives Aharonov-Bohm, la propagation des fonctions d'ondes est limitée à un ensemble fini de cellule du réseau appelé cage. De la dépendance en température des oscillations de période h/e mesurées sur le réseau mathcal{T}3 nous avons tiré une longueur caractéristique qui peut être rattachée au périmètre des cages. Un phénomène inattendu fut l'observation, pour des champs magnétiques plus importants, d'un doublement de fréquence des oscillations. Ces oscillations de période h/2e pouvant avoir une amplitude supérieure aux oscillations de période h/e, une interprétation en terme d'harmonique n'est pas possible. Enfin, l'influence de la largeur électrique des fils constituant le réseau et donc celle du nombre de canaux par brin a été étudiée en réalisant des grilles électrostatique. Les variations de l'amplitude des signaux en h/e et h/2e en fonction de la tension de grille ont été mesurés.

  20. Transition de phase quantique de type verrouillage-deverrouillage dans les canaux lineaires coherents des phases en rayures dans les doubles puits quantiques sous champ magnetique perpendiculaire

    NASA Astrophysics Data System (ADS)

    Faribault, Alexandre

    On peut creer un gaz electronique bidimensionnel en utilisant le potentiel de confinement d'une couche mince d'un semiconducteur dans un substrat fait d'une autre semiconducteur de gap plus eleve. L'ajout d'un champ magnetique perpendiculaire au plan de confinement modifie de facon drastique les proprietes du gaz electronique. Pour des densites et des valeurs du champ magnetique adequatement choisies, on obtient un etat fondamental en onde de densite de charge. Dans un systeme compose de deux de ces gaz bidimensionnels suffisamment rapproches l'un de l'autre, on prevoit theoriquement l'existence d'un etat fondamental compose d'une onde de densite de charge dans chacun des puits et d'une serie de regions lineaires ou l'on a une delocalisation coherente des electrons entre les deux puits. Dans cette these, on etudie le comportement a temperature nulle de cet etat fondamental en rayures coherentes. L'etude numerique des modes collectifs de ces phases laisse croire qu'un deverrouillage des canaux coherents est envisageable dans ce systeme. Afin d'etudier cette possibilite, nous construisons d'abord un modele effectif de canaux quasi-unidimensionnels couples qui permettent de reproduire correctement les excitations collectives a basse energie de la phase en rayures coherentes du double puits quantique. Dans un systeme de coordonnees adequatement choisi, ces excitations peuvent etre decrites par des ondes de pseudospin. Les parametres de ce modele effectif simple peuvent etre extraits des calculs des fonctions de reponse realises dans l'approximation Hartree-Fock dependante du temps (appelee aussi Generalized Random Phase Approximation). On constate l'efficacite de ce modele a decrire la dynamique basse energie du systeme pour une certaine plage de distances inter-puits. En retirant de ce modele les contributions a l'hamiltonien provenant des couplages de type Josephson entre les canaux, on obtient alors un systeme ou les canaux sont deverrouilles. Un traitement en

  1. Combined protein construct and synthetic gene engineering for heterologous protein expression and crystallization using Gene Composer

    SciTech Connect

    Raymond, Amy; Lovell, Scott; Lorimer, Don; Walchli, John; Mixon, Mark; Wallace, Ellen; Thompkins, Kaitlin; Archer, Kimberly; Burgin, Alex; Stewart, Lance

    2009-12-01

    With the goal of improving yield and success rates of heterologous protein production for structural studies we have developed the database and algorithm software package Gene Composer. This freely available electronic tool facilitates the information-rich design of protein constructs and their engineered synthetic gene sequences, as detailed in the accompanying manuscript. In this report, we compare heterologous protein expression levels from native sequences to that of codon engineered synthetic gene constructs designed by Gene Composer. A test set of proteins including a human kinase (P38{alpha}), viral polymerase (HCV NS5B), and bacterial structural protein (FtsZ) were expressed in both E. coli and a cell-free wheat germ translation system. We also compare the protein expression levels in E. coli for a set of 11 different proteins with greatly varied G:C content and codon bias. The results consistently demonstrate that protein yields from codon engineered Gene Composer designs are as good as or better than those achieved from the synonymous native genes. Moreover, structure guided N- and C-terminal deletion constructs designed with the aid of Gene Composer can lead to greater success in gene to structure work as exemplified by the X-ray crystallographic structure determination of FtsZ from Bacillus subtilis. These results validate the Gene Composer algorithms, and suggest that using a combination of synthetic gene and protein construct engineering tools can improve the economics of gene to structure research.

  2. Potentiel des images satellitaires multibandes a haute resolution spatiale pour la cartographie des componsants de l'eau en milieu cotier marin

    NASA Astrophysics Data System (ADS)

    Lavoie, Andre

    L'objectif principal que que nous poursuivons est de developper un modele de simulation du transfert radiatif eau-atmosphere adapte aux observations faites par le capteur Thematic Mapper (TM) de Landsat. Les informations que nous cherchons ont trait au milieu cotier marin et concernent les elements qui sont en suspension dans l'eau. Les images multibandes du capteur TM dans la partie visible du spectre, sont surtout visees par nos travaux. A la base de la simulation, nous utilisons un programme de simulation atmospherique, le code 6S, auquel nous greffons un modele de simulation du transfert radiatif dans la masse d'eau. Ce dernier estime le signal en fonction de 4 composants: l'eau, les pigments chlorophylliens (chlorophylle et phaeopigments), les matieres minerales et les substances organiques dissoutes. La concentration des differents composants sert de parametre d'entree pour definir le comportement optique de la masse d'eau. Le modele permet egalement de simuler une masse d'eau stratifiee si l'on connai t les concentrations des composants dans les differentes couches. Il inclut aussi la contribution du fond, selon sa nature et sa composition, ainsi que celle du miroitement du soleil et du ciel a la surface de l'eau. Les informations d'un echantillonnage de la masse d' eau synchronise avec le passage du satellite, a la baie des Chaleurs, d'une cartographie du couvert d'algues et d'un modele bathymetrique ont ete utilisees pour fixer les parametres de simulation par le modele. La comparaison montrent que le modele se comporte relativement bien surtout dans la bande TM2. Une erreur systematique de 2 valeurs numeriques en moyenne subsiste dans les trois bandes spectrales. Les resultats nous montrent que la visibilite du fond aux faibles profondeurs est un element tres important a considerer. Par ailleurs, l'analyse de sensibilite montre que les images TM sont plus sensibles aux concentrations en matieres minerales qu'aux pigments chlorophylliens et aux substances

  3. MO-A-BRD-05: Evaluation of Composed Lung Ventilation with 4DCT and Image Registration

    SciTech Connect

    Du, K; Bayouth, J; Reinhardt, J; Christensen, G; Zhao, B; Ding, K

    2014-06-15

    Purpose: Regional pulmonary function can be derived using fourdimensional computed tomography (4DCT) combined with deformable image registration. However, only peak inhale and exhale phases have been used thus far while the lung ventilation during intermediate phases is not considered. In our previous work, we have investigated the spatiotemporal heterogeneity of lung ventilation and its dependence on respiration effort. In this study, composed ventilation is introduced using all inspiration phases and compared to direct ventilation. Both methods are evaluated against Xe-CT derived ventilation. Methods: Using an in-house tissue volume preserving deformable image registration, unlike the direct ventilation method, which computes from end expiration to end inspiration, Jacobian ventilation maps were computed from one inhale phase to the next and then composed from all inspiration steps. The two methods were compared in both patients prior to RT and mechanically ventilated sheep subjects. In addition, they wereassessed for the correlation with Xe-CT derived ventilation in sheep subjects. Annotated lung landmarks were used to evaluate the accuracy of original and composed deformation field. Results: After registration, the landmark distance for composed deformation field was always higher than that for direct deformation field (0IN to 100IN average in human: 1.03 vs 1.53, p=0.001, and in sheep: 0.80 vs0.94, p=0.009), and both increased with longer phase interval. Direct and composed ventilation maps were similar in both sheep (gamma pass rate 87.6) and human subjects (gamma pass rate 71.9),and showed consistent pattern from ventral to dorsal when compared to Xe-CT derived ventilation. Correlation coefficient between Xe-CT and composed ventilation was slightly better than the direct method but not significant (average 0.89 vs 0.85, p=0.135). Conclusion: More strict breathing control in sheep subjects may explain higher similarity between direct and composed ventilation

  4. Quantum teleportation through an entangled state composed of displaced vacuum and single-photon states

    SciTech Connect

    Podoshvedov, S. A.

    2008-03-15

    We study a teleportation protocol of an unknown macroscopic qubit by means of a quantum channel composed of the displaced vacuum and single-photon states. The scheme is based on linear optical devices such as a beam splitter and photon number resolving detectors. A method based on conditional measurement is used to generate both the macroscopic qubit and entangled state composed from displaced vacuum and single-photon states. We show that such a qubit has both macroscopic and microscopic properties. In particular, we investigate a quantum teleportation protocol from a macroscopic object to a microscopic state.

  5. Musical tradition, insurrection, and resurrection: the life and legacy of composer/bassist Charles Mingus.

    PubMed

    St Louis, E K

    1999-01-01

    Charles Mingus was perhaps the foremost straight-ahead jazz upright bassist and composer of his generation, blending the inspirational influences of gospel, jazz improvisation, and art music leanings into a unique style all his own. His demise from amyotrophic lateral sclerosis (ALS) in his fifth decade robbed the world of one of the great creative voices of American music. Aspects of Mingus' life, his career as a bassist, bandleader, and composer, and his neuromuscular illness are discussed, emphasizing his legacy for the disparate fields of jazz and neurology. PMID:10718524

  6. Beyond Clara Schumann: Integrating Women Composers and Performers into General Music Classes

    ERIC Educational Resources Information Center

    Artesani, Laura

    2012-01-01

    To provide a comprehensive and balanced curriculum, the accomplishments of women composers and performers must be included in general music classes. This article addresses obstacles that have challenged women musicians and provides an outline for a unit that highlights seven American women who have achieved significant "firsts" in the world of…

  7. Impairment and Distress Judgments of Symptoms Composing Childhood Externalizing and Internalizing Syndromes

    ERIC Educational Resources Information Center

    Howell, Andrew J.; Watson, David C.

    2009-01-01

    The pattern of perceived dysfunction associated with symptoms composing the externalizing childhood disorder syndrome was compared to the pattern characterizing the internalizing syndrome. In Study 1, undergraduate students (N = 205) judged the social impairment, academic/occupational impairment and personal distress associated with symptoms from…

  8. Improving Students' Memory for Musical Compositions and Their Composers: Mneme that Tune!

    ERIC Educational Resources Information Center

    Carney, Russell N.; Levin, Joel R.

    2007-01-01

    Students enrolled in music appreciation and music history courses may find it difficult to remember composers' names and the titles of their compositions--particularly when retrieval is prompted by corresponding classical music themes. We sought to develop and validate a mnemonic approach in which musical themes were first recoded as more concrete…

  9. Compositional Strategies and Musical Creativity When Composing with Staff Notations versus Graphic Notations among Korean Students.

    ERIC Educational Resources Information Center

    Auh, Myung-Sook; Walker, Robert

    1999-01-01

    Examines compositional strategies and musical creativity of 38 seventh-grade students in junior high schools in Seoul (Korea) when composing with staff notations (traditional group) versus graphic notations (non-traditional group). Finds that musical creativity levels were judged to be significantly higher in the non-traditional compositions. (CMK)

  10. Children Composing and Their Visual-Spatial Approach to the Keyboard

    ERIC Educational Resources Information Center

    Roels, Johanna Maria; Van Petegem, Peter

    2015-01-01

    This study aims to contribute to the already existing findings of children's compositional strategies and products. Despite the abundance of research provided regarding the manner in which children approach composing, little has been found about how children deal, specifically, with the structure of the keyboard. Therefore, from a context in which…

  11. The Charlotte Civic Orchestra's Composer-in-the-Schools Project: Teaching Artistry in the Middle School

    ERIC Educational Resources Information Center

    Franklin, Elda

    2007-01-01

    This article describes the Composer-in-the-Schools Project, which successfully launched the Charlotte Civic Orchestra's Education and Outreach Program in a meaningful way by providing a unique opportunity for many young middle school orchestra students. Students who participated in the project, their parents, school administrators, and Charlotte…

  12. Reading as Mediated and Mediating Action: Composing Meaning for Literature through Multimedia Interpretive Texts.

    ERIC Educational Resources Information Center

    Smagorinsky, Peter; O'Donnell-Allen, Cindy

    1998-01-01

    Analyzes the effort of a small group of high school seniors to interpret the character of Laertes in Shakespeare's "Hamlet" through a "body biography," a life-sized human outline they filled with images and words representing their understanding of the character. Examines their discussion as they composed their text. (PA)

  13. Influence Techniques in Dyads Composed of Interdependent Middle and Lower Class Preschool Children. Final Report

    ERIC Educational Resources Information Center

    Rosenfeld, Howard M.; Russell, Richard L.

    The procedures by which children from lower and middle class backgrounds attempt to obtain rewarding outcomes from each other were observed under semicontrolled conditions. Ten male and 9 female dyads, each composed of 1 middle class and 1 lower class preschool child, were required to complete 12 simple block puzzles in which each was given some…

  14. Teaching the Passe Compose and the Imparfait in French: Traditional versus Aspectual Methods.

    ERIC Educational Resources Information Center

    Garrott, C. L.

    A study compared the effectiveness of two methods of teaching the passe compose and imparfait of French verbs. Sixty community college students were randomly assigned to two treatment groups, one taught with the traditional method focusing on rules governing tense application, and the other taught by the aspectual method, which treats the…

  15. Real-time rendering method and performance evaluation of composable 3D lenses for interactive VR.

    PubMed

    Borst, Christoph W; Tiesel, Jan-Phillip; Best, Christopher M

    2010-01-01

    We present and evaluate a new approach for real-time rendering of composable 3D lenses for polygonal scenes. Such lenses, usually called "volumetric lenses," are an extension of 2D Magic Lenses to 3D volumes in which effects are applied to scene elements. Although the composition of 2D lenses is well known, 3D composition was long considered infeasible due to both geometric and semantic complexity. Nonetheless, for a scene with multiple interactive 3D lenses, the problem of intersecting lenses must be considered. Intersecting 3D lenses in meaningful ways supports new interfaces such as hierarchical 3D windows, 3D lenses for managing and composing visualization options, or interactive shader development by direct manipulation of lenses providing component effects. Our 3D volumetric lens approach differs from other approaches and is one of the first to address efficient composition of multiple lenses. It is well-suited to head-tracked VR environments because it requires no view-dependent generation of major data structures, allowing caching and reuse of full or partial results. A Composite Shader Factory module composes shader programs for rendering composite visual styles and geometry of intersection regions. Geometry is handled by Boolean combinations of region tests in fragment shaders, which allows both convex and nonconvex CSG volumes for lens shape. Efficiency is further addressed by a Region Analyzer module and by broad-phase culling. Finally, we consider the handling of order effects for composed 3D lenses. PMID:20224135

  16. Processes Involved in Composing a Narration in a First and a Second Language.

    ERIC Educational Resources Information Center

    Bowie, David G.; Schallert, Diane L.

    1988-01-01

    In a study of the processes used to compose a story, 12 Portuguese/English bilingual adults created narrations for 2 published, wordless picture stories and, while viewing a videotape of their narration, recalled aloud the processes they used in constructing the stories. One study was narrated in Portuguese and the other in English. The narrations…

  17. Spatial Stories with Nomadic Narrators: Affect, Snapchat, and Feeling Embodiment in Youth Mobile Composing

    ERIC Educational Resources Information Center

    Wargo, Jon M.

    2015-01-01

    While the vast majority of scholarship on mobile media, social semiotics, and multimodality highlights work done "behind" the screen, few studies have considered the embodied processes of youth composing "with" and "through" mobile technology. This study, drawn from a larger critical qualitative connective…

  18. Bending Elasticity Modulus of Giant Vesicles Composed of Aeropyrum Pernix K1 Archaeal Lipid

    PubMed Central

    Genova, Julia; Poklar Ulrih, Nataša; Kralj-Iglič, Veronika; Iglič, Aleš; Bivas, Isak

    2015-01-01

    Thermally induced shape fluctuations were used to study elastic properties of giant vesicles composed of archaeal lipids C25,25-archetidyl (glucosyl) inositol and C25,25-archetidylinositol isolated from lyophilised Aeropyrum pernix K1 cells. Giant vesicles were created by electroformation in pure water environment. Stroboscopic illumination using a xenon flash lamp was implemented to remove the blur effect due to the finite integration time of the camera and to obtain an instant picture of the fluctuating vesicle shape. The mean weighted value of the bending elasticity modulus kc of the archaeal membrane determined from the measurements meeting the entire set of qualification criteria was (1.89 ± 0.18) × 10−19 J, which is similar to the values obtained for a membrane composed of the eukaryotic phospholipids SOPC (1.88 ± 0.17) × 10−19 J and POPC (2.00 ± 0.21) × 10−19 J. We conclude that membranes composed of archaeal lipids isolated from Aeropyrum pernix K1 cells have similar elastic properties as membranes composed of eukaryotic lipids. This fact, together with the importance of the elastic properties for the normal circulation through blood system, provides further evidence in favor of expectations that archaeal lipids could be appropriate for the design of drug delivery systems. PMID:25821933

  19. Composing across Multiple Media: A Case Study of Digital Video Production in a Fifth Grade Classroom

    ERIC Educational Resources Information Center

    Ranker, Jason

    2008-01-01

    This is a qualitative case study of two students' composing processes as they developed a documentary video about the Dominican Republic in an urban, public middle school classroom. While using a digital video editing program, the students moved across multiple media (the Web, digital video, books, and writing), drawing semiotic resources from…

  20. Multimodality: An Illuminating Approach to Unravelling the Complexities of Composing with ICT?

    ERIC Educational Resources Information Center

    Breeze, Nick

    2011-01-01

    Having previously been employed to investigate science and English classrooms and listening in the music classroom, theories of multimodality would appear to have much to contribute to an examination of group composing using Information and Communications Technology (ICT), owing to the multimodal nature of music software and group discourse. This…

  1. Reading during Sentence Composing and Error Correction: A Multilevel Analysis of the Influences of Task Complexity

    ERIC Educational Resources Information Center

    Van Waes, Luuk; Leijten, Marielle; Quinlan, Thomas

    2010-01-01

    In this study we investigated the role of reading, how writers coordinate editing with other writing processes. In particular, the experiment examines how the cognitive demands of sentence composing and the type of error influence the reading and writing performance. We devised an experimental writing task in which participants corrected an…

  2. Composing: The Art of Letting Your Right Brain Recognize What Your Left Brain is Recalling.

    ERIC Educational Resources Information Center

    Gage, Thomas

    The purpose of this paper is to show teachers that composing is the conveying of "knowing" and that students' growth in writing is frequently stunted by teachers' stress on correct spelling, word choice, and syntax in student writing. Topics discussed in the paper include the following: the presence of "memories and experiences, cinemas, radio…

  3. Research as a Recursive Process: Reconsidering "The Composing Processes of Unskilled College Writers" 35 Years Later

    ERIC Educational Resources Information Center

    Perl, Sondra

    2014-01-01

    This article describes Sondra Perl's retrospective review of the composing processes of unskilled college writers and whether her assumptions and values in the designing of research projects have changed over her long teaching career. She uses her college dissertation "Five Writers Writing" as the basis to reflect on the authors and…

  4. Popular Periodicals and Rhetoric & Composition Textbooks in the Nineteenth Century: A Cultural Conversation on Composing Oneself.

    ERIC Educational Resources Information Center

    Welsch, Kathleen A.

    In 19th century America, talk of manners and morals as integral components of American character filled a significant space in public discourse. Lessons on how to compose oneself properly and models of appropriate behavior abounded in the form of essays, stories, poetry, editorials, and travel literature. This conversation on character influenced…

  5. Weighted Maximum-a-Posteriori Estimation in Tests Composed of Dichotomous and Polytomous Items

    ERIC Educational Resources Information Center

    Sun, Shan-Shan; Tao, Jian; Chang, Hua-Hua; Shi, Ning-Zhong

    2012-01-01

    For mixed-type tests composed of dichotomous and polytomous items, polytomous items often yield more information than dichotomous items. To reflect the difference between the two types of items and to improve the precision of ability estimation, an adaptive weighted maximum-a-posteriori (WMAP) estimation is proposed. To evaluate the performance of…

  6. Elicitation of the "Passe Compose" in French Preschoolers with and without Specific Language Impairment

    ERIC Educational Resources Information Center

    Royle, Phaedra; Thordardottir, Elin T.

    2008-01-01

    This study examines inflectional abilities in French-speaking children with specific language impairment (SLI) using a verb elicitation task. Eleven children with SLI and age-matched controls (37-52 months) participated in the experiment. We elicited the "passe compose" using eight regular and eight irregular high frequency verbs matched for age…

  7. Learning Design and Proscription: How Generative Activity Was Promoted in Music Composing

    ERIC Educational Resources Information Center

    Breeze, Nick

    2009-01-01

    This article reports on a particular aspect of a PhD study into pupil composing in music classrooms with information and communications technology (ICT). Two case studies based in England investigated the work of two groups of pupils in different phases of education, one aged 12-13 (secondary) and the other 10-11 (primary). A theoretical lens that…

  8. Estimating Conditional Standard Errors of Measurement for Tests Composed of Testlets.

    ERIC Educational Resources Information Center

    Lee, Guemin

    The primary purpose of this study was to investigate the appropriateness and implication of incorporating a testlet definition into the estimation of the conditional standard error of measurement (SEM) for tests composed of testlets. The five conditional SEM estimation methods used in this study were classified into two categories: item-based and…

  9. Tier 1 and Tier 2 Early Intervention for Handwriting and Composing

    ERIC Educational Resources Information Center

    Berninger, Virginia W.; Rutberg, Judith E.; Abbott, Robert D.; Garcia, Noelia; Anderson-Youngstrom, Marci; Brooks, Allison; Fulton, Cynthia

    2006-01-01

    Three studies evaluated Tier 1 early intervention for handwriting at a critical period for literacy development in first grade and one study evaluated Tier 2 early intervention in the critical period between third and fourth grades for composing on high stakes tests. The results contribute to knowledge of research-supported handwriting and…

  10. The Heart of the Matter: Composing Music with an Adolescent with Special Needs

    ERIC Educational Resources Information Center

    Bell, Adam Patrick

    2008-01-01

    As a support worker for adolescents with special needs, I have found that they have few opportunities to play music. While previous research emphasizes that students with special needs can enjoy music in multiple capacities, little has been written about their ability to play, improvise, or compose. I employed a qualitative approach for this case…

  11. The Organisation and Assessment of Composing at Key Stage 4 in English Secondary Schools

    ERIC Educational Resources Information Center

    Savage, Jonathan; Fautley, Martin

    2011-01-01

    This paper explores secondary school music teachers' current practice with regard to the organisation and assessment of composing at Key Stage 4. It draws on research undertaken on a nation-wide basis in England, via the use of two online surveys and face-to-face interviews. In terms of the organisation of classroom composition, the study found…

  12. Suggest-Choose-Plan-Compose: A Strategy to Help Students Learn to Write

    ERIC Educational Resources Information Center

    Wiesendanger, Katherine Davis; Perry, Jeannine Rajewski; Braun, Gretchen

    2011-01-01

    This article describes a strategy to support students' development of creative writing and construction of text in a sequential manner. The goal of the Suggest-Choose-Plan-Compose (SCPC) strategy is to improve students' ability to create a story by helping them clarify their thoughts as they generate and organize ideas and basic story elements.…

  13. Bending elasticity modulus of giant vesicles composed of aeropyrum pernix k1 archaeal lipid.

    PubMed

    Genova, Julia; Ulrih, Nataša Poklar; Kralj-Iglič, Veronika; Iglič, Aleš; Bivas, Isak

    2015-01-01

    Thermally induced shape fluctuations were used to study elastic properties of giant vesicles composed of archaeal lipids C25,25-archetidyl (glucosyl) inositol and C25,25-archetidylinositol isolated from lyophilised Aeropyrum pernix K1 cells. Giant vesicles were created by electroformation in pure water environment. Stroboscopic illumination using a xenon flash lamp was implemented to remove the blur effect due to the finite integration time of the camera and to obtain an instant picture of the fluctuating vesicle shape. The mean weighted value of the bending elasticity modulus kc of the archaeal membrane determined from the measurements meeting the entire set of qualification criteria was (1.89 ± 0.18) × 10-19 J, which is similar to the values obtained for a membrane composed of the eukaryotic phospholipids SOPC (1.88 ± 0.17) × 10-19 J and POPC (2.00 ± 0.21) ´ 10-19 J. We conclude that membranes composed of archaeal lipids isolated from Aeropyrum pernix K1 cells have similar elastic properties as membranes composed of eukaryotic lipids. This fact, together with the importance of the elastic properties for the normal circulation through blood system, provides further evidence in favor of expectations that archaeal lipids could be appropriate for the design of drug delivery systems. PMID:25821933

  14. Reading, Writing, and Knowing: The Role of Disciplinary Knowledge in Comprehension and Composing.

    ERIC Educational Resources Information Center

    Ackerman, John M.

    1991-01-01

    Analyzes synthesis essays of graduate students for the importance and origin of information and for the quality of key rhetorical moves. Confirms the interrelatedness of comprehension and composing processes and illustrates how writers, with varying levels of topic familiarity, use both their knowledge of disciplinary topics and their experience…

  15. Flipping the Composing Process: Collaborative Drafting and Résumé Writing

    ERIC Educational Resources Information Center

    Anders, Abram

    2016-01-01

    This article argues for a flipped learning approach to business and professional communication composing processes. Flipped learning sequences can scaffold more robust engagement with prewriting activities and support opportunities for in-class collaborative and facilitated drafting exercises. These types of learning experiences offer numerous…

  16. Writing as Embodied, College Football Plays as Embodied: Extracurricular Multimodal Composing

    ERIC Educational Resources Information Center

    Rifenburg, J. Michael

    2014-01-01

    Recent explorations position multimodality as a largely curricular practice wherein the body typically is not figured as a potential mode of meaning making. Such a projection not only fails to acknowledge extracurricular uses of such a rhetoric but also fails to acknowledge the role of the body in and especially for composing. In hopes of…

  17. Redesigning and Transforming: A Case Study of the Role of Semiotic Import in Early Composing Processes

    ERIC Educational Resources Information Center

    Ranker, Jason

    2009-01-01

    In this article, I explore the role of semiotic import (Van Leeuwen, 2005) in the composing processes of three bilingual students (six to seven years old) emerging as writers of English. Using social semiotic (Van Leeuwen, 2005) and design (New London Group, 2000) frameworks, I trace a qualitative "micro-history" of how the students imported…

  18. Let Cinderella and Luke Skywalker Help You Teach the Passe Compose and Imperfect.

    ERIC Educational Resources Information Center

    Terry, Robert M.

    Instructional materials for the passe compose and imperfect tenses in French use the technique of presenting familiar stories in the foreign language, written in the present tense, which students must place in the past by changing verb forms. The objective is to avoid the disadvantages of simply translating verb tenses and to allow the student to…

  19. Transdisciplinary Dimensions in the Composing Activities of Children: Transfer of Strategies and Transformation of Knowledge

    ERIC Educational Resources Information Center

    Roels, Johanna Maria; Van Petegem, Peter

    2016-01-01

    Existing studies show the value of using visual expression as a means of teaching children to understand and create music. This study aspires to point out an additional valuable aspect, namely, the influence composing via visual expression--whereby children transform their own drawings--may have on children's subsequent compositional processes.…

  20. A Particle Swarm Optimization Approach to Composing Serial Test Sheets for Multiple Assessment Criteria

    ERIC Educational Resources Information Center

    Yin, Peng-Yeng; Chang, Kuang-Cheng; Hwang, Gwo-Jen; Hwang, Gwo-Haur; Chan, Ying

    2006-01-01

    To accurately analyze the problems of students in learning, the composed test sheets must meet multiple assessment criteria, such as the ratio of relevant concepts to be evaluated, the average discrimination degree, difficulty degree and estimated testing time. Furthermore, to precisely evaluate the improvement of student's learning performance…

  1. Envisioning Collaborative Composing in Music Education: Learning and Negotiation of Meaning in "operabyyou.com"

    ERIC Educational Resources Information Center

    Partti, Heidi; Westerlund, Heidi

    2013-01-01

    This qualitative instrumental case study examines collaborative composing in the "operabyyou.com" online music community from the perspective of learning by utilising the concept of a "community of practice" as a heuristic frame. The article suggests that although informal music practices offer important opportunities for…

  2. Donkey Kong in Little Bear Country: A First Grader's Composing Development in the Media Spotlight.

    ERIC Educational Resources Information Center

    Dyson, Anne Haas

    2001-01-01

    Draws on data collected in an ethnographic project in an urban first grade to examine how media use informs child composing. Focuses on the influence of visual media involving animation. Concludes with a consideration of the teaching challenges posed, and opportunities offered, by the children's media use. (Author)

  3. Caracterisation pratique des systemes quantiques et memoires quantiques auto-correctrices 2D

    NASA Astrophysics Data System (ADS)

    Landon-Cardinal, Olivier

    Cette these s'attaque a deux problemes majeurs de l'information quantique: - Comment caracteriser efficacement un systeme quantique? - Comment stocker de l'information quantique? Elle se divise done en deux parties distinctes reliees par des elements techniques communs. Chacune est toutefois d'un interet propre et se suffit a elle-meme. Caracterisation pratique des systemes quantiques. Le calcul quantique exige un tres grand controle des systemes quantiques composes de plusieurs particules, par exemple des atomes confines dans un piege electromagnetique ou des electrons dans un dispositif semi-conducteur. Caracteriser un tel systeme quantique consiste a obtenir de l'information sur l'etat grace a des mesures experimentales. Or, chaque mesure sur le systeme quantique le perturbe et doit done etre effectuee apres avoir reprepare le systeme de facon identique. L'information recherchee est ensuite reconstruite numeriquement a partir de l'ensemble des donnees experimentales. Les experiences effectuees jusqu'a present visaient a reconstruire l'etat quantique complet du systeme, en particulier pour demontrer la capacite de preparer des etats intriques, dans lesquels les particules presentent des correlations non-locales. Or, la procedure de tomographie utilisee actuellement n'est envisageable que pour des systemes composes d'un petit nombre de particules. Il est donc urgent de trouver des methodes de caracterisation pour les systemes de grande taille. Dans cette these, nous proposons deux approches theoriques plus ciblees afin de caracteriser un systeme quantique en n'utilisant qu'un effort experimental et numerique raisonnable. - La premiere consiste a estimer la distance entre l'etat realise en laboratoire et l'etat cible que l'experimentateur voulait preparer. Nous presentons un protocole, dit de certification, demandant moins de ressources que la tomographie et tres efficace pour plusieurs classes d'etats importantes pour l'informatique quantique. - La seconde

  4. Une recension des écrits concernant la réalité psychoaffective des femmes ayant une vulvodynie : Difficultés rencontrées et stratégies développées

    PubMed Central

    Cantin-Drouin, Maude; Damant, Dominique; Turcotte, Daniel

    2008-01-01

    HISTORIQUE : Au cours des trois dernières décennies, une attention grandissante a été portée à l’étude du syndrome de vulvodynie, soit un inconfort vulvaire chronique inexpliqué, éprouvé en l’absence de pathologie précisée. En plus d’avoir des répercussions physiques, l’expérience de la vulvodynie comporte une dimension psychosociale. OBJECTIF : Cet article vise à faire une recension des écrits sur la réalité psychoaffective des femmes qui éprouvent une vulvodynie. MÉTHODE : Une recherche documentaire basée sur une exploration systématique de textes présentant des résultats de recherche et recensés dans les principales banques de données en sciences sociales, dont Dissertation Abstracts, Current Contents et PsycINFO, a été réalisée. RÉSULTATS : Cette recension des écrits révèle, malgré la présence de certains résultats divergents, que les femmes ayant une vulvodynie affrontent souvent des difficultés identitaires et psychologiques, qui sont influencées notamment par les normes sociales de sexualité et de féminité. Pour composer avec ces difficultés, les femmes développent différentes stratégies visant à diminuer le stress occasionné par la douleur et à améliorer leur bien-être psychologique. CONCLUSION : Les difficultés relationnelles et psychologiques vécues par les femmes ayant une vulvodynie ne découlent pas seulement de la douleur physique, mais aussi du sens qu’elles lui accordent, souvent influencé par les discours sociaux sur l’hétérosexualité et la féminité. Il importe donc d’intervenir auprès des femmes en tenant compte de l’influence du contexte social tout en poursuivant le développement des connaissances sur les aspects psychosociaux de cette expérience. PMID:18592063

  5. Peste des Petits Ruminants Virus.

    PubMed

    Baron, M D; Diallo, A; Lancelot, R; Libeau, G

    2016-01-01

    Peste des petits ruminants virus (PPRV) causes a severe contagious disease of sheep and goats and has spread extensively through the developing world. Because of its disproportionately large impact on the livelihoods of low-income livestock keepers, and the availability of effective vaccines and good diagnostics, the virus is being targeted for global control and eventual eradication. In this review we examine the origin of the virus and its current distribution, and the factors that have led international organizations to conclude that it is eradicable. We also review recent progress in the molecular and cellular biology of the virus and consider areas where further research is required to support the efforts being made by national, regional, and international bodies to tackle this growing threat. PMID:27112279

  6. The enhancement of existing DES Maplet interface

    NASA Astrophysics Data System (ADS)

    Abdullah, Nur Lina; Mutalip, Rasidah Abdull; Abdullah, Kamilah

    2014-07-01

    This study pertains to the process of Data Encryption Standard, DES. DES consists of encryption and decryption processes linked with mathematical elements such as algebra and number theory. Preliminary, studies revealed that most of mathematics students face a problem in understanding the complicated process of DES. In modern learning methods, learning environment becomes more interesting with the use of computer and a variety of mathematical software packages. Several mathematical softwares such as Maple, Mathematica, Mathlab and Sage were developed in order to fulfill the specific calculation requirements. Correspondingly, motivated from that, this study incorporated with Maple to enhance the existing DES Maplet interface to be more interactive and user-friendly compared to the original version.

  7. Copernic: la piste des influences arabes

    NASA Astrophysics Data System (ADS)

    Khalatbari, A.; Bonnet-Bidaud, J. M.

    2004-10-01

    Copernic a-t-il connu le travail des astronomes du Moyen-Orient ? S'en est-il inspiré pour élaborer sa théorie de l'héliocentrisme ? C'est l'hypothèse avancée par certains historiens des sciences pour comprendre le génie de celui qui, le premier, a placé le Soleil au centre du monde. Enquête.

  8. Etudes des Reactions de Transfert LITHIUM-7/LITHIUM -6

    NASA Astrophysics Data System (ADS)

    Baddou, Djafer

    Les reactions de transfert de deux nucleons ^7Li/^6Li(^3He, rm p)^8Be/^9Be ont ete effectuees a partir d'um faisceau d'^3He initialement polarise et d'energie incidente egale a 4.58 MeV au centre de la cible. Le faisceau d'^3He est simplement ionise et il est accelere par l'accelerateur Van de Graaff de l'Universite Laval. Ce faisceau d' ^3He est de polarisation egale a 40% et il est obtenu a partir d'une source d'^3He a l'etat metastable. Nous avons decrit la reaction depuis la production et le transport du faisceau initial de l'^3 He jusqu'a la chambre de reaction. Par la suite, nous avons obtenu les distributions angulaires de la section efficace differentielle et du pouvoir d'analyse de ces reactions. Elles ont ete comparees a la theorie DWBA a l'approximation zero. La theorie a montre qu'il s'agit d'un transfert de deux particules independants (neutron, proton) pour le cas de la reaction ^7Li( ^3He,rm p)^9Be et d'un transfert de "cluster" deuteron pour le cas de la reaction ^6Li(^3He, rm p)^8Be. Notons que pour cette reaction l'instabilite du ^8Be ne nous permet pas d'avoir une diffusion elastique permettant la determination des parametres du modele optique entre ce noyau et la particule diffusee. Afin de contourner cette difficulte, nous supposons que le ^8 Be est un noyau compose de deux particules alpha et nous avons teste cette hypothese avec les reactions ^6Li(^3He, rm p)^8Be et ^7Li( ^3He,rm d)^8Be. Nous mentionnons a la fin que nous avons observe que l'etat fondamental de la reaction ^6Li( ^3He,rm p)^8Be et l'etat excite 2.43 MeV de la reaction ^7Li(^3He,rm p)^9Be sont des reactions directes alors que le premier etat excite (2.96 MeV) de la reaction ^6Li(^3He,rm p)^8Be et l'etat fondamental de la reaction ^7Li(^3He,rm p)^9Be peuvent etre domines par une reaction a noyau compose.

  9. Modified Hyperspheres Algorithm to Trace Homotopy Curves of Nonlinear Circuits Composed by Piecewise Linear Modelled Devices

    PubMed Central

    Vazquez-Leal, H.; Jimenez-Fernandez, V. M.; Benhammouda, B.; Filobello-Nino, U.; Sarmiento-Reyes, A.; Ramirez-Pinero, A.; Marin-Hernandez, A.; Huerta-Chua, J.

    2014-01-01

    We present a homotopy continuation method (HCM) for finding multiple operating points of nonlinear circuits composed of devices modelled by using piecewise linear (PWL) representations. We propose an adaptation of the modified spheres path tracking algorithm to trace the homotopy trajectories of PWL circuits. In order to assess the benefits of this proposal, four nonlinear circuits composed of piecewise linear modelled devices are analysed to determine their multiple operating points. The results show that HCM can find multiple solutions within a single homotopy trajectory. Furthermore, we take advantage of the fact that homotopy trajectories are PWL curves meant to replace the multidimensional interpolation and fine tuning stages of the path tracking algorithm with a simple and highly accurate procedure based on the parametric straight line equation. PMID:25184157

  10. Absence of amusia and preserved naming of musical instruments in an aphasic composer.

    PubMed

    Tzortzis, C; Goldblum, M C; Dang, M; Forette, F; Boller, F

    2000-04-01

    M.M., a right-handed, 74 year old professional musician and composer, presented with a progressive aphasia with a severe anomia. His musical competence was apparently totally preserved, and he continued his activity as a composer. There was a striking discrepancy between his impaired naming of nonmusical stimuli and his normal naming of musical instruments' sounds. We suggest that the preservation of skills in the musical domain results from an expanded cortical representation of this function in the left hemisphere, secondary to his lifelong formal training, and to the high level of his professional competence. As for his preserved naming of musical instruments, we argue that the early age-of-acquisition and higher than "normal" frequency/familiarity for names of musical instruments facilitate the access to their lexical representation and/or their retrieval within the lexicon. PMID:10815708

  11. Particle alignment and clustering in sheared granular materials composed of platy particles.

    PubMed

    Boton, Mauricio; Estrada, Nicolas; Azéma, Emilien; Radjaï, Farhang

    2014-11-01

    By means of molecular dynamics simulations, we investigate the texture and local ordering in sheared packings composed of cohesionless platy particles. The morphology of large packings of platy particles in quasistatic equilibrium is complex due to the combined effects of local nematic ordering of the particles and anisotropic orientations of contacts between particles. We find that particle alignment is strongly enhanced by the degree of platyness and leads to the formation of face-connected clusters of exponentially decaying size. Interestingly, due to dynamics in continuous shearing, this ordering phenomenon emerges even in systems composed of particles of very low platyness differing only slightly from spherical shape. The number of clusters is an increasing function of platyness. However, at high platyness the proportion of face-face interactions is too low to allow for their percolation throughout the system. PMID:25412821

  12. Modified hyperspheres algorithm to trace homotopy curves of nonlinear circuits composed by piecewise linear modelled devices.

    PubMed

    Vazquez-Leal, H; Jimenez-Fernandez, V M; Benhammouda, B; Filobello-Nino, U; Sarmiento-Reyes, A; Ramirez-Pinero, A; Marin-Hernandez, A; Huerta-Chua, J

    2014-01-01

    We present a homotopy continuation method (HCM) for finding multiple operating points of nonlinear circuits composed of devices modelled by using piecewise linear (PWL) representations. We propose an adaptation of the modified spheres path tracking algorithm to trace the homotopy trajectories of PWL circuits. In order to assess the benefits of this proposal, four nonlinear circuits composed of piecewise linear modelled devices are analysed to determine their multiple operating points. The results show that HCM can find multiple solutions within a single homotopy trajectory. Furthermore, we take advantage of the fact that homotopy trajectories are PWL curves meant to replace the multidimensional interpolation and fine tuning stages of the path tracking algorithm with a simple and highly accurate procedure based on the parametric straight line equation. PMID:25184157

  13. Composable Security Proof for Continuous-Variable Quantum Key Distribution with Coherent States

    NASA Astrophysics Data System (ADS)

    Leverrier, Anthony

    2015-02-01

    We give the first composable security proof for continuous-variable quantum key distribution with coherent states against collective attacks. Crucially, in the limit of large blocks the secret key rate converges to the usual value computed from the Holevo bound. Combining our proof with either the de Finetti theorem or the postselection technique then shows the security of the protocol against general attacks, thereby confirming the long-standing conjecture that Gaussian attacks are optimal asymptotically in the composable security framework. We expect that our parameter estimation procedure, which does not rely on any assumption about the quantum state being measured, will find applications elsewhere, for instance, for the reliable quantification of continuous-variable entanglement in finite-size settings.

  14. Optical memory development. Volume 3: The membrane light value page composer

    NASA Technical Reports Server (NTRS)

    Cosentino, L. S.; Nagle, E. M.; Stewart, W. C.

    1972-01-01

    The feasibility of producing a page composer for optical memory systems using thin, deformable, membrane-mirror elements as light valves was investigated. The electromechanical and optical performances of such elements were determined both analytically and experimentally. It was found that fast switching (approximately 10 microseconds), high-contrast (10 or greater), fatigue-free operation over missions of cycles, and efficient utilization of input light could be obtained with membrane light valves. Several arrays of 64 elements were made on substrates with feedthroughs, allowing access to individual elements from the backside of the substrate. Single light valves on such arrays were successfully operated with the transistors designed and produced for selection and storage at each bit location. This simulated the operation of a prototype page composer with semiconductor chips beam-lead bonded to the back of the substrate.

  15. Towards Composing Data Aware Systems Biology Workflows on Cloud Platforms: A MeDICi-based Approach

    SciTech Connect

    Gorton, Ian; Liu, Yan; Yin, Jian; Kulkarni, Anand V.; Wynne, Adam S.

    2011-09-08

    Cloud computing is being increasingly adopted for deploying systems biology scientific workflows. Scientists developing these workflows use a wide variety of fragmented and competing data sets and computational tools of all scales to support their research. To this end, the synergy of client side workflow tools with cloud platforms is a promising approach to share and reuse data and workflows. In such systems, the location of data and computation is essential consideration in terms of quality of service for composing a scientific workflow across remote cloud platforms. In this paper, we describe a cloud-based workflow for genome annotation processing that is underpinned by MeDICi - a middleware designed for data intensive scientific applications. The workflow implementation incorporates an execution layer for exploiting data locality that routes the workflow requests to the processing steps that are colocated with the data. We demonstrate our approach by composing two workflowswith the MeDICi pipelines.

  16. Ccaffeine framework : composing and debugging applications interactively and running them statically.

    SciTech Connect

    Armstrong, Robert C.; Allan, Benjamin A.

    2005-02-01

    Ccaffeine is a Common Component Architecture (CCA) framework devoted to high-performance computing. In this note we give an overview of the system features of Ccaffeine and CCA that support component-based HPC application development. Object-oriented, single-threaded and lightweight, Ccaffeine is designed to get completely out of the way of the running application after it has been composed from components. Ccaffeine is one of the few frameworks, CCA or otherwise, that can compose and run applications on a parallel machine interactively and then automatically generate a static, possibly self-tuning, executable for production runs. Users can experiment with and debug applications interactively, improving their productivity. When the application is ready, a script is automatically generated, parsed and turned into a static executable for production runs. Within this static executable, dynamic replacement of components can be performed by self-tuning applications.

  17. PepComposer: computational design of peptides binding to a given protein surface.

    PubMed

    Obarska-Kosinska, Agnieszka; Iacoangeli, Alfredo; Lepore, Rosalba; Tramontano, Anna

    2016-07-01

    There is a wide interest in designing peptides able to bind to a specific region of a protein with the aim of interfering with a known interaction or as starting point for the design of inhibitors. Here we describe PepComposer, a new pipeline for the computational design of peptides binding to a given protein surface. PepComposer only requires the target protein structure and an approximate definition of the binding site as input. We first retrieve a set of peptide backbone scaffolds from monomeric proteins that harbor the same backbone arrangement as the binding site of the protein of interest. Next, we design optimal sequences for the identified peptide scaffolds. The method is fully automatic and available as a web server at http://biocomputing.it/pepcomposer/webserver. PMID:27131789

  18. Diffusion des Metaux et Evolution Stellaire

    NASA Astrophysics Data System (ADS)

    Turcotte, Sylvain

    Nous presentons dans cette these des modeles d'evolution stellaire incorporant la diffusion microscopique de maniere consistante. Pour la premiere fois, on a calcule l'evolution d'etoiles en tenant compte en detail de l'impact des variations d'abondances sur leur structure. Nous utilisons des spectres monochromatiques pour chacun des elements les plus abondants dans un melange solaire pour recalculer l'opacite pour les abondances et les conditions locales dans l'interieur d'une etoile au cours de son evolution. Nos modeles montrent que la diffusion atomique des metaux a un effet important sur les opacites dan les etoiles de plus de 1.3Msolar ou l'abondance du fer et des autres elements du pic du fer varient substantiellement. Ces etoiles, sans rotation ou champ magnetique, sont proches des etoiles de type Fm-Am dans lesquelles on observe une legere surabondance d'elements du pic du fer en plus d'une sous-abondance de calcium, sous-abondance que l'on obtient egalement. Nous obtenons cependant des surabondances depassant un facteur 10 pour les etoiles de plus de 1.4Msolar ce qui suggere qu'il existe un ou plusieurs mecanismes limitant la diffusion microscopique. La surabondance du fer en surface cause une augmentation, qui peut atteindre un facteur sept, de l'opacite a la limite de la zone convective. Ceci cause un accroissement de la temperature effective et de la masse de la zone convective comparativement aux modeles n'incluant que la diffusion de l'helium. Il s'agit la du principal effet de la diffusion sur la structure interne de ces etoiles. La diffusions n'a pas d'influence sur l'evolution de coeur stellaire dans les etoiles significativement plus massives quie le Soleil. Nous avons verife que l'utilisation de modeles consistants avec diffusion n'apporte pas d'amelioration sensible aux modeles solaires. Les forces radiatives calculees a partir des spectres d'OPAL pour les elements du pic du fer representent une fraction importante de la gravite. On obtient des

  19. Gene Composer: database software for protein construct design, codon engineering, and gene synthesis

    PubMed Central

    Lorimer, Don; Raymond, Amy; Walchli, John; Mixon, Mark; Barrow, Adrienne; Wallace, Ellen; Grice, Rena; Burgin, Alex; Stewart, Lance

    2009-01-01

    Background To improve efficiency in high throughput protein structure determination, we have developed a database software package, Gene Composer, which facilitates the information-rich design of protein constructs and their codon engineered synthetic gene sequences. With its modular workflow design and numerous graphical user interfaces, Gene Composer enables researchers to perform all common bio-informatics steps used in modern structure guided protein engineering and synthetic gene engineering. Results An interactive Alignment Viewer allows the researcher to simultaneously visualize sequence conservation in the context of known protein secondary structure, ligand contacts, water contacts, crystal contacts, B-factors, solvent accessible area, residue property type and several other useful property views. The Construct Design Module enables the facile design of novel protein constructs with altered N- and C-termini, internal insertions or deletions, point mutations, and desired affinity tags. The modifications can be combined and permuted into multiple protein constructs, and then virtually cloned in silico into defined expression vectors. The Gene Design Module uses a protein-to-gene algorithm that automates the back-translation of a protein amino acid sequence into a codon engineered nucleic acid gene sequence according to a selected codon usage table with minimal codon usage threshold, defined G:C% content, and desired sequence features achieved through synonymous codon selection that is optimized for the intended expression system. The gene-to-oligo algorithm of the Gene Design Module plans out all of the required overlapping oligonucleotides and mutagenic primers needed to synthesize the desired gene constructs by PCR, and for physically cloning them into selected vectors by the most popular subcloning strategies. Conclusion We present a complete description of Gene Composer functionality, and an efficient PCR-based synthetic gene assembly procedure with mis

  20. Mid-infrared tunable optical polarization converter composed of asymmetric graphene nanocrosses.

    PubMed

    Cheng, Hua; Chen, Shuqi; Yu, Ping; Li, Jianxiong; Deng, Li; Tian, Jianguo

    2013-05-01

    We present a mid-IR highly tunable optical polarization converter composed of asymmetric graphene nanocrosses. It can convert linearly polarized light to circularly and elliptically polarized light or exhibit a giant optical activity at different wavelengths. The transmitted wavelength and polarization states can also be dynamically tuned by varying the Fermi energy of graphene, without reoptimizing and refabricating the nanostructures. This offers a further step in developing a controllable polarization converter. PMID:23632554

  1. Emil Votocek (1872-1950): A Tribute to the Chemist-Composer-Lexicographer

    NASA Astrophysics Data System (ADS)

    Kauffman*, George B.; Jursík**, Frantisek; Rae***, Ian D.

    1999-04-01

    Emil Votocek (1872-1950), Professor of Experimental Inorganic and Organic Chemistry at the Czech Technical University at Prague (1905-1939) and cofounder and coeditor of the journal Collection of Czechoslovak Chemical Communications, was an authority on the chemistry of carbohydrates, especially sugars. Although primarily known for his research on organic, analytical, inorganic, and plant chemistry, this polyglot scholar and lexicographer was also a composer who wrote nearly 60 musical compositions during the relatively short period of 15 years.

  2. Geometry of Prismatic Tensegrity Constructions Composed of Three and Four-strut Cells

    NASA Astrophysics Data System (ADS)

    Olejníková, Tatiana

    2014-11-01

    In the paper there is described geometry of double layer tensegrity constructions composed of prismatic cells with rhombic configuration of three or four strut bases so-called prismatic Tensegrity constructions. There are described bi-dimensional assemblies creating double layer grids of three or four-strut cells with a node-on-node junction. The grids can be planar, of one or two curvature constructions.

  3. Constructing three-dimensional detachable and composable computer models of the head and neck.

    PubMed

    Fan, Min; Dai, Peishan; Zheng, Buhong; Li, Xinchun

    2015-06-01

    The head and neck region has a complex spatial and topological structure, three-dimensional (3D) computer model of the region can be used in anatomical education, radiotherapy planning and surgical training. However, most of the current models only consist of a few parts of the head and neck, and the 3D models are not detachable and composable. In this study, a high-resolution 3D detachable and composable model of the head and neck was constructed based on computed tomography (CT) serial images. First, fine CT serial images of the head and neck were obtained. Then, a color lookup table was created for 58 structures, which was used to create anatomical atlases of the head and neck. Then, surface and volume rendering methods were used to reconstruct 3D models of the head and neck. Smoothing and polygon reduction steps were added to improve 3D rendering effects. 3D computer models of the head and neck, including the sinus, pharynx, vasculature, nervous system, endocrine system and glands, muscles, bones and skin, were reconstructed. The models consisted of 58 anatomical detachable and composable structures and each structure can be displayed individually or together with other structures. PMID:26091713

  4. COMPOSE: A semisupervised learning framework for initially labeled nonstationary streaming data.

    PubMed

    Dyer, Karl B; Capo, Robert; Polikar, Robi

    2014-01-01

    An increasing number of real-world applications are associated with streaming data drawn from drifting and nonstationary distributions that change over time. These applications demand new algorithms that can learn and adapt to such changes, also known as concept drift. Proper characterization of such data with existing approaches typically requires substantial amount of labeled instances, which may be difficult, expensive, or even impractical to obtain. In this paper, we introduce compacted object sample extraction (COMPOSE), a computational geometry-based framework to learn from nonstationary streaming data, where labels are unavailable (or presented very sporadically) after initialization. We introduce the algorithm in detail, and discuss its results and performances on several synthetic and real-world data sets, which demonstrate the ability of the algorithm to learn under several different scenarios of initially labeled streaming environments. On carefully designed synthetic data sets, we compare the performance of COMPOSE against the optimal Bayes classifier, as well as the arbitrary subpopulation tracker algorithm, which addresses a similar environment referred to as extreme verification latency. Furthermore, using the real-world National Oceanic and Atmospheric Administration weather data set, we demonstrate that COMPOSE is competitive even with a well-established and fully supervised nonstationary learning algorithm that receives labeled data in every batch. PMID:24806641

  5. Photonic crystals composed of virtual pillars with magnetic walls: Photonic band gaps and double Dirac cones

    NASA Astrophysics Data System (ADS)

    Kim, Seong-Han; Kim, Soeun; Kee, Chul-Sik

    2016-08-01

    Photonic crystals composed of virtual pillars with magnetic walls are proposed. A virtual pillar with a magnetic wall can be created inside a parallel perfect electric conductor plate waveguide by introducing a circular perfect magnetic conductor patch in the upper perfect electric conductor plate of the waveguide. The virtual pillar mimics a perfect magnetic conductor pillar with a radius less than that of the circular patch because electromagnetic waves can slightly penetrate the wall. Furthermore, the photonic band structures of a triangular photonic crystal composed of virtual pillars for the transverse electromagnetic modes of the waveguide are investigated. They are very similar to those of a triangular photonic crystal composed of infinitely long perfect electric conductor cylinders for transverse magnetic modes. The similarity between the two different photonic crystals is well understood by the boundary conditions of perfect electric and magnetic conductor surfaces. A double Dirac cone at the center of the Brillouin zone is observed and thus the virtual pillar triangular photonic crystal can act a zero-refractive-index material at the Dirac point frequency.

  6. Hydration characteristics and environmental friendly performance of a cementitious material composed of calcium silicate slag.

    PubMed

    Zhang, Na; Li, Hongxu; Zhao, Yazhao; Liu, Xiaoming

    2016-04-01

    Calcium silicate slag is an alkali leaching waste generated during the process of extracting Al2O3 from high-alumina fly ash. In this research, a cementitious material composed of calcium silicate slag was developed, and its mechanical and physical properties, hydration characteristics and environmental friendly performance were investigated. The results show that an optimal design for the cementitious material composed of calcium silicate slag was determined by the specimen CFSC7 containing 30% calcium silicate slag, 5% high-alumina fly ash, 24% blast furnace slag, 35% clinker and 6% FGD gypsum. This blended system yields excellent physical and mechanical properties, confirming the usefulness of CFSC7. The hydration products of CFSC7 are mostly amorphous C-A-S-H gel, rod-like ettringite and hexagonal-sheet Ca(OH)2 with small amount of zeolite-like minerals such as CaAl2Si2O8·4H2O and Na2Al2Si2O8·H2O. As the predominant hydration products, rod-like ettringite and amorphous C-A-S-H gel play a positive role in promoting densification of the paste structure, resulting in strength development of CFSC7 in the early hydration process. The leaching toxicity and radioactivity tests results indicate that the developed cementitious material composed of calcium silicate slag is environmentally acceptable. This study points out a promising direction for the proper utilization of calcium silicate slag in large quantities. PMID:26691955

  7. Recreating the real, realizing the imaginary--a composer's preoccupation with acoustic space

    NASA Astrophysics Data System (ADS)

    Godman, Rob

    2002-11-01

    For centuries composers have been concerned with spatialization of sound and with the use of acoustic spaces to create feeling, atmosphere, and musical structure. This paper will explore Rob Godman's own use of sound in space, including (1) his treatment of ancient Vitruvian principles and how they are combined with new technologies; (2) an exploration of virtual journeys through real and imaginary acoustic spaces; (3) how sounds might be perceived in air, liquid, and solids; and (4) how technology has allowed composers to realize ideas that previously had only existed in the imagination. While focusing on artistic concerns, the paper will provide information on research carried out by the composer into acoustic spaces that are able to transform in real time with the aid of digital technology (Max/MSP software with sensor technology) and how these have been used in installation and pre-recorded work. It will also explore digital reconstructions of Vitruvian theatres and how we perceive resonance and ambience in the real and virtual world.

  8. Effet Hall et Magnetisme des Alliages Amorphes Nickel-Zirconium Fabriques Par Pulverisation

    NASA Astrophysics Data System (ADS)

    Morel, Robert

    Cette these se situe dans le cadre d'une etude des proprietes electroniques et structurales des alliages metalliques amorphes, en cours depuis quelques annees a l'Universite de Montreal. Ce programme nous a entre autres amene a caracteriser la magnetoresistivite et l'effet Hall d'alliages FeZr, CoZr et NiZr, ce qui a permis de mettre en evidence deux caracteristiques de l'effet Hall: Dans les alliages amorphes ferromagnetiques, la resistivite elevee engendre un effet Hall extraordinaire beaucoup plus important que celui enregistre dans les metaux cristallins. La polarisation des spins entrai ne une asymetrie de la diffusion qui, tant dans les phases cristalline et amorphe, est tenue responsable de cette contribution. L'autre particularite du comportement de Hall de ces systemes est le renversement de signe du coefficient de Hall ordinaire, qui passe du negatif au positif dans les echantillons plus riches en zirconium. Dans les metaux cristallins, un modele d'electrons libres predit un signe negatif a moins que la conduction ne soit dominee par les trous. Or, dans un milieu desordonne les memes concepts sont difficilement applicables et de nouvelles theories ont du etre elaborees pour expliquer ce phenomene. Jusqu'a maintenant, l'etude des alliages amorphes nickel-zirconium s'est faite surtout a partir d'echantillons fabriques par trempe sur roue. Malheureusement cette technique ne permet pas la fabrication d'alliages contenant plus de 70% de nickel, a l'exception du seul compose Ni _{90}Zr_{10 }. Pour pallier a cette lacune et etendre nos connaissance a l'ensemble de la gamme de compositions, nous avons fabrique par pulverisation cathodique des echantillons NiZr amorphes--et quelques alliages cristallins tres riches en nickel--couvrant une bonne partie de la gamme interdite par la technique de trempe sur roue. Dans un premier temps, par comparaison avec les resultats connus nous avons mis en evidence les similitudes et les differences entre les alliages obtenus par

  9. Onset of superradiant instabilities in the composed Kerr-black-hole-mirror bomb

    NASA Astrophysics Data System (ADS)

    Hod, Shahar

    2014-09-01

    It was first pointed out by Press and Teukolsky that a system composed of a spinning Kerr black hole surrounded by a reflecting mirror may develop instabilities. The physical mechanism responsible for the development of these exponentially growing instabilities is the superradiant amplification of bosonic fields confined between the black hole and the mirror. A remarkable feature of this composed black-hole-mirror-field system is the existence of a critical mirror radius, rmstat, which supports stationary (marginally-stable) field configurations. This critical (‘stationary’) mirror radius marks the boundary between stable and unstable black-hole-mirror-field configurations: composed systems whose confining mirror is situated in the region rmcomposed systems whose confining mirror is situated in the region rm>rmstat are unstable (that is, there are confined field modes which grow exponentially over time). In the present paper we explore this critical (marginally-stable) boundary between stable and explosive black-hole-mirror-field configurations. It is shown that the innermost (smallest) radius of the confining mirror which allows the extraction of rotational energy from a spinning Kerr black hole approaches the black-hole horizon radius in the extremal limit of rapidly-rotating black holes. We find, in particular, that this critical mirror radius (which marks the onset of superradiant instabilities in the composed system) scales linearly with the black-hole temperature. For a confined field mode of given harmonic indexes (l,m), the stationary mirror radius is a decreasing function of the BH angular momentum abar. In other words, rapidly-rotating Kerr BHs are characterized by stationary mirror radii which are smaller (closer to the BH horizon) than the corresponding stationary mirror radii of slowly-rotating BHs. For a given value of the spheroidal harmonic index l of the

  10. A second-order planar gradiometer composed of concentric superconductive loops

    NASA Astrophysics Data System (ADS)

    Kuriki, S.; Isobe, Y.; Mizutani, Y.

    1987-01-01

    A planar gradiometer composed of three concentric superconductive loops is analyzed. The gradiometer performs the second derivative with a rotational symmetry in a form of ∂2Bz/∂r2, where r2=x2+y2. In response to the biomagnetic field generated by a current dipole, an isoflux line distribution which resembles well the magnetic field distribution is obtained. The location and the strength of the current-dipole source can readily be estimated from the isoflux pattern. Reduction of the magnetic field noise from distant sources with respect to the signal of a near source is calculated to be comparable with that of conventional axial gradiometers.