931 resultados para ELECTRONIC PUBLICATIONS


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Translation of: Kibernetika i elektro-vychislitel'nai︠a︡ tekhnika (romanized form)

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Coverage as of 2/20/03: 1997.

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Supplements 1941/1942-1945/1946.

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Mode of access: Internet.

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Catalogue of the officers, faculty and students for the academic year 1859-60 / Ypsilanti Union School -- Biennial catalogue and circular of the officers, teachers and pupils of the Ypsilanti Union Seminary : together with the courses of study, rules and regulations for the school year 1868-69 -- Union Lyceum, public, Ypsilanti Seminary, Saturday eve., Feb. 26, '70 [program] : order of exercises -- Ninth annual commencement of the Ypsilanti Union Seminary, Friday evening, June 24, 1870 -- Circular containing organization, courses of study and rules and regulations of the public schools of Ypsilanti, Michigan, 1885 -- Circular of the Ypsilanti high school for the academic year 1885-86 -- Annual report and circular containing courses of study of the public schools of Ypsilanti, Michigan, 1892 -- Announcement, Ypsilanti public schools, 1892-93 -- Circular of information, August, 1895 / Ypsilanti High School -- Catalog of the officers, instructors, and students of the Ypsilanti High School for the school year 1898-99 -- Catalog of the officers, instructors, and students of the Ypsilanti High School, for the school year 1899-1900 -- Catalog of the officers, teachers, and students of the Ypsilanti High School for the school year 1900-1901 -- Commemoration exercises celebrating the close of the nineteenth century high school hall, Thursday evening, Dec. 20, 1900 / Ypsilanti High School -- Annual report of the Superintendent of the public schools of Ypsilanti, Michigan for the school year 1908-1909 -- The public schools, Ypsilanti, Michigan : course of study, rules and regulations, reports for 1910-11 and general information -- Annual catalogue, 1911-12 / high school, Ypsilanti, Michigan.

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ACM Computing Classification System (1998): I.7.4.

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A novel method to fabricate chemically linked conducting polymer–biopolymer composites that are intrinsically flexible and conducting for functional electrode applications is presented. Polypyrrole was synthesised in situ during the cellulose regeneration process using the 1-butyl-3-methylimidazolium chloride ionic liquid as a solvent medium. The obtained polypyrrole–cellulose composite was chemically blended and showed flexible polymer properties while retaining the electronic properties of a conducting polymer. Addition of an ionic liquid such as trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, enhanced the flexibility of the composite. The functional application of these materials in the electrochemically controlled release of a model drug has been demonstrated. This strategy opens up a new design for a wide spectrum of materials for smart electronic device applications wherein the functionality of doping and de-doping of conducting polymers is retained and their processability issue is addressed by exploiting an ionic liquid route.

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We present a reformulation of the hairy-probe method for introducing electronic open boundaries that is appropriate for steady-state calculations involving nonorthogonal atomic basis sets. As a check on the correctness of the method we investigate a perfect atomic wire of Cu atoms and a perfect nonorthogonal chain of H atoms. For both atom chains we find that the conductance has a value of exactly one quantum unit and that this is rather insensitive to the strength of coupling of the probes to the system, provided values of the coupling are of the same order as the mean interlevel spacing of the system without probes. For the Cu atom chain we find in addition that away from the regions with probes attached, the potential in the wire is uniform, while within them it follows a predicted exponential variation with position. We then apply the method to an initial investigation of the suitability of graphene as a contact material for molecular electronics. We perform calculations on a carbon nanoribbon to determine the correct coupling strength of the probes to the graphene and obtain a conductance of about two quantum units corresponding to two bands crossing the Fermi surface. We then compute the current through a benzene molecule attached to two graphene contacts and find only a very weak current because of the disruption of the π conjugation by the covalent bond between the benzene and the graphene. In all cases we find that very strong or weak probe couplings suppress the current.

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Understanding the magnetic properties of graphenic nanostructures is instrumental in future spintronics applications. These magnetic properties are known to depend crucially on the presence of defects. Here we review our recent theoretical studies using density functional calculations on two types of defects in carbon nanostructures: Substitutional doping with transition metals, and sp$^3$-type defects created by covalent functionalization with organic and inorganic molecules. We focus on such defects because they can be used to create and control magnetism in graphene-based materials. Our main results are summarized as follows: i)Substitutional metal impurities are fully understood using a model based on the hybridization between the $d$ states of the metal atom and the defect levels associated with an unreconstructed D$_{3h}$ carbon vacancy. We identify three different regimes, associated with the occupation of distinct hybridization levels, which determine the magnetic properties obtained with this type of doping; ii) A spin moment of 1.0 $\mu_B$ is always induced by chemical functionalization when a molecule chemisorbs on a graphene layer via a single C-C (or other weakly polar) covalent bond. The magnetic coupling between adsorbates shows a key dependence on the sublattice adsorption site. This effect is similar to that of H adsorption, however, with universal character; iii) The spin moment of substitutional metal impurities can be controlled using strain. In particular, we show that although Ni substitutionals are non-magnetic in flat and unstrained graphene, the magnetism of these defects can be activated by applying either uniaxial strain or curvature to the graphene layer. All these results provide key information about formation and control of defect-induced magnetism in graphene and related materials.

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L’arbre en ville offre plusieurs bienfaits, et ce, même s’il est souvent confronté à des conditions de vie difficiles. Au cours des années, la foresterie urbaine a suscité plusieurs travaux de recherches. Ce projet visait à faire un recensement des publications scientifiques de recherche en foresterie urbaine, à faire l’état de la situation des municipalités en matière de foresterie urbaine et à identifier les besoins de recherche en foresterie urbaine des municipalités canadiennes de 5 000 habitants et plus. Le premier objectif a été réalisé en utilisant plusieurs bases de données d’articles scientifiques et des mots clefs en foresterie urbaine. Un sondage pancanadien a permis de réaliser les deux autres objectifs. Le recensement que nous avons effectué des publications en foresterie urbaine depuis 1800 a montré, comme pour les publications scientifiques en général, mais de façon encore plus marquée, un accroissement de leur nombre ces dernières années. Ce recensement a aussi permis de révéler que les préoccupations de recherche touchent surtout l’effet des arbres sur la santé humaine et la qualité de l’air. L’identification des besoins de recherche réalisée auprès des responsables des espaces verts a permis de constater qu’il y avait toujours place pour la recherche dans ce domaine. Les municipalités veulent connaître, entre autres, quelles espèces d’arbres sont adaptées à l’environnement urbain, quel est l’effet des arbres sur le ruissellement des eaux de pluie et sur la santé humaine. Nous avons aussi constaté qu’il y avait un manque de transfert de connaissances entre les chercheurs et les responsables d’espaces verts ou que les recherches menées ne répondent pas aux besoins exprimés par les répondants. Le présent mémoire a permis de mieux cerner les besoins de recherche des municipalités canadiennes et permettra aux chercheurs de mieux définir les priorités de recherche en foresterie urbaine.

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This chapter discusses the historical development, current practice and future prospects of the self-archiving of research papers in open-access repositories (so-called 'e-print archives'). It describes how the development of interoperable e-print repositories in a number of subject communities has shown that self-archiving can benefit academic researchers (and potentially others) by enabling quick and easy access to the research literature and therefore maximising the impact potential of papers. Realising that the possible benefits are high and the technical entry barriers low, many organisations such as universities have recently tried to encourage widespread self-archiving by setting up institutional repositories. However, major barriers to self-archiving remain - most of them cultural and managerial. There are concerns about quality control, intellectual property rights, disturbing the publishing status quo, and workload. Ways in which these issues are currently being addressed are discussed in this chapter. A number of self-archiving initiatives in different countries have been set up to address the concerns and to kick-start e-print repository use. However, issues remain which require further investigation; those discussed in this chapter include discipline differences, definitions of 'publication', versioning problems, digital preservation, costing and funding models, and metadata standards. The ways in which these issues are resolved will be important in determining the future of self-archiving. Possible futures are discussed with particular reference to journal publishing and quality control. If widely adopted, self-archiving might come to assume a central place in the scholarly communication process, but a great deal of restructuring of the process needs to take place before this potential can be realised.

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Visible, near-infrared, IR and Raman spectra of magnesian gaspeite are presented. Nickel ion is the main source of the electronic bands as it is the principal component in the mineral where as the bands in IR and Raman spectra are due to the vibrational processes in the carbonate ion as an entity. The combination of electronic absorption and vibrational spectra (including near-infrared, FTIR and Raman) of magnesian gaspeite are explained in terms of the cation co-ordination and the behaviour of CO32– anion in the Ni–Mg carbonate. The electronic absorption spectrum consists of three broad and intense bands at 8130, 13160 and 22730 cm–1 due to spin-allowed transitions and two weak bands at 20410 and 30300 cm–1 are assigned to spin-forbidden transitions of Ni2+ in an octahedral symmetry. The crystal field parameters evaluated from the observed bands are Dq = 810; B = 800 and C = 3200 cm–1. The two bands in the near-infrared spectrum at 4330 and 5130 cm–1 are overtone and combination of CO32– vibrational modes. For the carbonate group, infrared bands are observed at 1020 cm–1(1 ), 870 cm–1 (2), 1418 cm–1 (3) and 750 cm–1 (4), of which3, the asymmetric stretching mode is most intense. Three well resolved Raman bands at 1571, 1088 and 331 cm–1 are assigned to 3, 1 and MO stretching vibrations.