4,117 research outputs found

    A Comparative Study of Tourism and Hospitality Education in the United Kingdom and France

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    pp.55-95Sufficient historical detail is provided on the development of tourism in France and the United Kingdom to provide a context for the discussion of how comparative education practices can inform and improve the provision of university education in Europe. Findings from a recent empirical comparative study of university provision for tourism and hospitality studies are presented and analysed to progress the work in this field of research. Finally, very recent moves, especially in industry-specific education in France, are combined with the teaching initiative called CLIL (Content & Language Integrated Learning) to offer a way forward for educators in tourism and hospitality departments in higher education in Europe

    Spontaneous curvature cancellation in forced thin sheets

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    In this paper we report numerically observed spontaneous vanishing of mean curvature on a developable cone made by pushing a thin elastic sheet into a circular container. We show that this feature is independent of thickness of the sheet, the supporting radius and the amount of deflection. Several variants of developable cone are studied to examine the necessary conditions that lead to the vanishing of mean curvature. It is found that the presence of appropriate amount of radial stress is necessary. The developable cone geometry somehow produces the right amount of radial stress to induce just enough radial curvature to cancel the conical azimuthal curvature. In addition, the circular symmetry of supporting container edge plays an important role. With an elliptical supporting edge, the radial curvature overcompensates the azimuthal curvature near the minor axis and undercompensates near the major axis. Our numerical finding is verified by a crude experiment using a reflective plastic sheet. We expect this finding to have broad importance in describing the general geometrical properties of forced crumpling of thin sheets.Comment: 13 pages, 12 figures, revtex

    Implementation of a registry and open access genetic testing program for inherited retinal diseases within a non‐profit foundation

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    The Foundation Fighting Blindness is a 50‐year old 501c(3) non‐profit organization dedicated to supporting the development of treatments and cures for people affected by the inherited retinal diseases (IRD), a group of clinical diagnoses that include orphan diseases such as retinitis pigmentosa, Usher syndrome, and Stargardt disease, among others. Over $760 M has been raised and invested in preclinical and clinical research and resources. Key resources include a multi‐national clinical consortium, an international patient registry with over 15,700 members that is expanding rapidly, and an open access genetic testing program that provides no cost comprehensive genetic testing to people clinically diagnosed with an IRD living in the United States. These programs are described with particular focus on the challenges and outcomes of establishing the registry and genetic testing program.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162760/2/ajmgc31825_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162760/1/ajmgc31825.pd

    The Casimir force on a surface with shallow nanoscale corrugations: Geometry and finite conductivity effects

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    We measure the Casimir force between a gold sphere and a silicon plate with nanoscale, rectangular corrugations with depth comparable to the separation between the surfaces. In the proximity force approximation (PFA), both the top and bottom surfaces of the corrugations contribute to the force, leading to a distance dependence that is distinct from a flat surface. The measured Casimir force is found to deviate from the PFA by up to 15%, in good agreement with calculations based on scattering theory that includes both geometry effects and the optical properties of the material

    Rim curvature anomaly in thin conical sheets revisited

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    This paper revisits one of the puzzling behaviors in a developable cone (d-cone), the shape obtained by pushing a thin sheet into a circular container of radius R R by a distance η \eta [E. Cerda, S. Chaieb, F. Melo, and L. Mahadevan, {\sl Nature} {\bf 401}, 46 (1999)]. The mean curvature was reported to vanish at the rim where the d-cone is supported [T. Liang and T. A. Witten, {\sl Phys. Rev. E} {\bf 73}, 046604 (2006)]. We investigate the ratio of the two principal curvatures versus sheet thickness hh over a wider dynamic range than was used previously, holding R R and η \eta fixed. Instead of tending towards 1 as suggested by previous work, the ratio scales as (h/R)1/3(h/R)^{1/3}. Thus the mean curvature does not vanish for very thin sheets as previously claimed. Moreover, we find that the normalized rim profile of radial curvature in a d-cone is identical to that in a "c-cone" which is made by pushing a regular cone into a circular container. In both c-cones and d-cones, the ratio of the principal curvatures at the rim scales as (R/h)5/2F/(YR2) (R/h)^{5/2}F/(YR^{2}) , where F F is the pushing force and Y Y is the Young's modulus. Scaling arguments and analytical solutions confirm the numerical results.Comment: 25 pages, 12 figures. Added references. Corrected typos. Results unchange

    Optimal strategies for a game on amenable semigroups

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    The semigroup game is a two-person zero-sum game defined on a semigroup S as follows: Players 1 and 2 choose elements x and y in S, respectively, and player 1 receives a payoff f(xy) defined by a function f from S to [-1,1]. If the semigroup is amenable in the sense of Day and von Neumann, one can extend the set of classical strategies, namely countably additive probability measures on S, to include some finitely additive measures in a natural way. This extended game has a value and the players have optimal strategies. This theorem extends previous results for the multiplication game on a compact group or on the positive integers with a specific payoff. We also prove that the procedure of extending the set of allowed strategies preserves classical solutions: if a semigroup game has a classical solution, this solution solves also the extended game.Comment: 17 pages. To appear in International Journal of Game Theor

    Structural investigation of Fe silicide films grown by pulsed laser deposition

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    Pulsed laser deposition was used to grow epitaxial β‐FeSi2 films on Si(111) (1×1) and Si(111) (7×7) with the following epitaxial orientations: β‐FeSi2(001)//Si(111) with β‐FeSi2[010]//Si〈110〉 and three rotational variants. Silicide growth was influenced by substrate temperature and deposition rate, but not by the structure of the starting surface. Films containing both β‐FeSi2 and FeSi were formed at low substrate temperatures and high deposition rates, while films containing only β‐FeSi2 were formed at higher substrate temperatures and lower deposition rates. FeSi grains had the following epitaxial relationship to the Si substrate, FeSi(111)//Si(111) with FeSi(110)//Si(112). The microstructure of the silicide films varied with film thickness, as did the roughness at the silicide/Si interface. These results suggest that an Fe‐rich environment was created during the growth of the silicide films.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70762/2/JAPIAU-76-4-2202-1.pd

    Light-Cone Quantization of the Liouville Model

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    We present the quantization of the Liouville model defined in light-cone coordinates in (1,1) signature space. We take advantage of the representation of the Liouville field by the free field of the Backl\"{u}nd transformation and adapt the approch by Braaten, Curtright and Thorn. Quantum operators of the Liouville field +ϕ\partial_{+}\phi, ϕ\partial_{-}\phi, egϕe^{g\phi}, e2gϕe^{2g\phi} are constructed consistently in terms of the free field. The Liouville model field theory space is found to be restricted to the sector with field momentum P+=PP_{+}=-P_{-}, P+>0P_{+}> 0 , which is a closed subspace for the Liouville theory operator algebra.Comment: 16 p, EFI-92-6

    Absolute photoionization cross section measurements of the Kr I-isoelectronic sequence

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    Photoionization spectra have been recorded in the 4s, 4p and 3d resonance regions for the Kr Iisoelectronic sequence using both the dual laser produced plasma technique (at DCU) to produce photoabsorption spectra, and the merged ion beam and synchrotron radiation technique (at ASTRID) to measure absolute photoionization cross sections. Profile parameters are compared for the 4s − np resonances of Rb+ and Sr2+. Many new 4p " ns, md transitions are identified with the aid of Hartree-Fock calculations, and consistent quantum defects are observed for the various ns and md Rydberg series. Absolute single and double photoionization cross sections recorded in the 3d region for Rb+ and Sr2+ ions show preferential decay via double photoionization. This is only the second report where both the DLP technique and the merged beam technique have been used simultaneously to record photoionization spectra, and the advantages of both techniques (i.e. better resolution in the case of DLP and values for absolute photoionization cross sections in the case of the merged beam technique) are highlighted
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