52,025 research outputs found

    Assessing the geographic dimensions of London's innovation networks

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    A wide range of authors have highlighted the potential benefits for innovation that may arise from effective networking between organisations along and across the supply-chain. As many organisations have downsized or out-sourced basic research activities Universities have an increasingly important role within such networks. A number of UK initiatives have been established to encourage greater 'entanglement' between academia and commerce; the London Technology Network is one example which is intended to encourage interactions between London's leading research institutes and innovation organisations. Using the detailed data acquired by this network this development paper is intended to investigate the geographic distribution of these activities with the aim of establishing the extent to which location and/or distance play a significant role in participation in the network's activities. A wide range of authors have highlighted the potential benefits for innovation that may arise from effective networking between organisations along and across the supply-chain. As many organisations have downsized or out-sourced basic research activities Universities have an increasingly important role within such networks. A number of UK initiatives have been established to encourage greater 'entanglement' between academia and commerce; the London Technology Network is one example which is intended to encourage interactions between London's leading research institutes and innovation organisations. Using the detailed data acquired by this network this development paper is intended to investigate the geographic distribution of these activities with the aim of establishing the extent to which location and/or distance play a significant role in participation in the network's activities

    Size effect and the quadratic temperature dependence of the transverse magnetoresistivity in "size-effect" tungsten single crystals

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    The transverse magnetoresistivity of pure tungsten single crystals with a residual resistivity ratio ρ293K/ρ4.2K of about 75000 was measured from 4.2 to 20 K and in magnetic fields of up to 15 T. The size effect, i.e. the linear dependence of the magnetoconductivity on the inverse cross sample dimensions, was studied in detail at high fields. We show that the size effect can be used for the separation of the contributions from the electron-surface and the electron-phonon scattering mechanisms to the full conductivity. We demonstrate that the electron-phonon scattering leads to the exponential temperature dependence of the conductivity, and the interference between the electron-phonon and the electron-surface processes leads to a new scattering mechanism "electron-phonon-surface" with a quadratic temperature dependence of the magnetoconductivity. © Published under licence by IOP Publishing Ltd

    Aerodynamic influence coefficient method using singularity splines

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    A numerical lifting surface formulation, including computed results for planar wing cases is presented. This formulation, referred to as the vortex spline scheme, combines the adaptability to complex shapes offered by paneling schemes with the smoothness and accuracy of loading function methods. The formulation employes a continuous distribution of singularity strength over a set of panels on a paneled wing. The basic distributions are independent, and each satisfied all the continuity conditions required of the final solution. These distributions are overlapped both spanwise and chordwise. Boundary conditions are satisfied in a least square error sense over the surface using a finite summing technique to approximate the integral. The current formulation uses the elementary horseshoe vortex as the basic singularity and is therefore restricted to linearized potential flow. As part of the study, a non planar development was considered, but the numerical evaluation of the lifting surface concept was restricted to planar configurations. Also, a second order sideslip analysis based on an asymptotic expansion was investigated using the singularity spline formulation

    The Use and Value of Data Warehousing in Higher Education

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    Industry is experiencing a dramatic increase in the use of data warehousing techniques, but higher education has been slow to follow suit. This paper illustrates some common uses of data warehousing in industry, provides higher education analogues and suggests the potential value of data warehousing techniques to colleges and universities

    The Reformation in the Relation to Elementary Education

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    While here and there a practical deduction may be drawn, the one aim of this paper is to present from a historical angle the Reformation in its relation to elementary education. In order to limit ourselves to the requirements of a treatise of this sort, we shall refer for the most part only to the educational thoughts of the Reformation author, Martin Luther

    Pathways to double ionization of atoms in strong fields

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    We discuss the final stages of double ionization of atoms in a strong linearly polarized laser field within a classical model. We propose that all trajectories leading to non-sequential double ionization pass close to a saddle in phase space which we identify and characterize. The saddle lies in a two degree of freedom subspace of symmetrically escaping electrons. The distribution of longitudinal momenta of ions as calculated within the subspace shows the double hump structure observed in experiments. Including a symmetric bending mode of the electrons allows us to reproduce the transverse ion momenta. We discuss also a path to sequential ionization and show that it does not lead to the observed momentum distributions.Comment: 10 pages, 10 figures; fig.6 and 7 exchanged in the final version accepted for publication in Phys. Rev.

    The universal functorial equivariant Lefschetz invariant

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    We introduce the universal functorial equivariant Lefschetz invariant for endomorphisms of finite proper G-CW-complexes, where G is a discrete group. We use K_0 of the category of "phi-endomorphisms of finitely generated free RPi(G,X)-modules". We derive results about fixed points of equivariant endomorphisms of cocompact proper smooth G-manifolds.Comment: 33 pages; shortened version of the author's PhD thesis, supervised by Wolfgang Lueck, Westfaelische Wilhelms-Universitaet Muenster, 200
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