2,098 research outputs found

    Cyclic homogeneous Riemannian manifolds

    Get PDF
    In spin geometry, traceless cyclic homogeneous Riemannian manifolds equipped with a homogeneous spin structure can be viewed as the simplest manifolds after Riemannian symmetric spin spaces. In this paper, we give some characterizations and properties of cyclic and traceless cyclic homogeneous Riemannian manifolds and we obtain the classification of simply-connected cyclic homogeneous Riemannian manifolds of dimension less than or equal to four. We also present a wide list of examples of non-compact irreducible Riemannian 33-symmetric spaces admitting cyclic metrics and give the expression of these metrics

    Homogeneous spin Riemannian manifolds with the simplest Dirac operator

    Get PDF
    We show the existence of nonsymmetric homogeneous spin Riemannian manifolds whose Dirac operator is like that on a Riemannian symmetric spin space. Such manifolds are exactly the homogeneous spin Riemannian manifolds (M,g)(M,g) which are traceless cyclic with respect to some quotient expression M=G/KM=G/K and reductive decomposition g=km\mathfrak{g} = \mathfrak{k} \oplus \mathfrak{m}. Using transversally symmetric fibrations of noncompact type, we give a list of them

    Improved thermal isolation of silicon suspended platforms for an all-silicon thermoelectric microgenerator based on large scale integration of Si nanowires as thermoelectric material

    Get PDF
    Special suspended micro-platforms have been designed as a part of silicon compatible planar thermoelectric microgenerators. Bottom-up grown silicon nanowires are going to bridge in the future such platforms to the surrounding silicon bulk rim. They will act as thermoelectric material thus configuring an all-silicon thermoelectric device. In the new platform design other additional bridging elements (usually auxiliary support silicon beams) are substituted by low conductance thin film dielectric membranes in order to maximize the temperature difference developed between both areas. These membranes follow a sieve-like design that allows fabricating them with a short additional wet anisotropic etch step. © Published under licence by IOP Publishing Ltd.Peer ReviewedPostprint (published version

    Alterated Identities in Brazil: From the Samba Culture to the Sertanejo Culture

    Get PDF
    Cultural references regarding Brazilianness have generally been associated with samba, carnival, colors, and an aesthetic compendium typical of a pre-modernity recreated in cities like Rio de Janeiro or Salvador. A foreign observer would like to see in these lands references that would transport him to Antônio Carlos Jobim’s “The Girl from Ipanema” song or to identity traits that would indicate a ‘tropical Brazil’ related to people dancing in the rhythm of samba and bossa nova, and Copacabana beach. However, many socio-cultural changes progressively impacted the consumption of musical and aesthetic styles among Brazilians. Changes concerning musical styles’ preferences led to significant cultural changes that would modify the notion of Brazilianness imaginary in the first decades of the 21st century. The present paper addresses this eventual cultural and aesthetic references change, showing with decisive force what has been called ‘sertanejo culture’ in Brazil. Keywords: Brazilian culture; Cultural identity; Samba culture; Sertanejo culture; Musical styles. DOI: 10.7176/RHSS/12-18-04 Publication date:September 30th 202

    Business cycle patterns in European regions

    Get PDF
    The aim of this paper is threefold. First, we analyze the comovements of business cycles in European regions. Second, we date these business cycles and identify clusters of regions with similar business cycle behavior, using Finite Mixture Markov models. Third, we develop a new index to measure within-country homogeneity. We find that comovement among regions is, on average, quite low, although it increased during the convergence process prior to the euro cash and after the onset of the Great Recession. We identify five different groups of European regions. We also find heterogeneity in the size of border effects

    Inflation comovements in advanced economies: Facts and drivers*

    Get PDF
    In this paper, we analyse inflation comovements and their macroeconomic drivers across a wide set of advanced economies. We find a high degree of inflation interdependence, which is highest for euro area countries, which show strong trade links and share a common monetary policy. In contrast, core inflation interdependence is very limited. We also find that inflation interconnectedness is a medium- to long-run phenomenon. Inflation comovements across countries are well explained by an open economy new Keynesian Phillips curve

    HOMOGENEOUS RIEMANNIAN STRUCTURES ON BERGER 3-SPHERES

    Get PDF
    corecore