1,530 research outputs found

    The psychological reality of rhythm classes: Perceptual studies

    Get PDF
    Linguists have traditionally classified languages into three rhythm classes, namely stress-timed, syllable-timed and mora-timed languages. However, this classification has remained controversial for various reasons: the search for reliable acoustic cues to the different rhythm types has long remained elusive; some languages are claimed to belong to none of the three classes; and few perceptual studies has bolstered the notion. We have previously proposed an acoustic/phonetic model of the different types of linguistic rhythm, and of their categorisation as such by listeners. Here, we present perceptual experiments that directly test the notion of rhythm classes, our model's predictions, and the question of intermediate languages. Language discrimination experiments were run using a speech resynthesis technique to ensure that only rhythmic cues were available to the subjects. Languages investigated were English, Dutch, Spanish, Catalan and Polish. Our results are consistent with the idea that English and Dutch are stress-timed, Spanish and Catalan are syllable-timed, but Polish seems to be different from any other language studied and thus may constitute a new rhythm class. We propose that perceptual studies tapping the ability to discriminate languages' rhythm are the proper way to generate more empirical data relevant to rhythm typology

    A DTN routing scheme for quasi-deterministic networks with application to LEO satellites topology

    Get PDF
    We propose a novel DTN routing algorithm, called DQN, specifically designed for quasi-deterministic networks with an application to satellite constellations. We demonstrate that our proposal efficiently forwards the information over a satellite network derived from the Orbcomm topology while keeping a low replication overhead. We compare our algorithm against other well-known DTN routing schemes and show that we obtain the lowest replication ratio without the knowledge of the topology and with a delivery ratio of the same order of magnitude than a reference theoretical optimal routing

    Energy conservation and numerical stability for the reduced MHD models of the non-linear JOREK code

    Get PDF
    In this paper we present a rigorous derivation of the reduced MHD models with and without parallel velocity that are implemented in the non-linear MHD code JOREK. The model we obtain contains some terms that have been neglected in the implementation but might be relevant in the non-linear phase. These are necessary to guarantee exact conservation with respect to the full MHD energy. For the second part of this work, we have replaced the linearized time stepping of JOREK by a non-linear solver based on the Inexact Newton method including adaptive time stepping. We demonstrate that this approach is more robust especially with respect to numerical errors in the saturation phase of an instability and allows to use larger time steps in the non-linear phase

    High-order implicit palindromic discontinuous Galerkin method for kinetic-relaxation approximation

    Get PDF
    We construct a high order discontinuous Galerkin method for solving general hyperbolic systems of conservation laws. The method is CFL-less, matrix-free, has the complexity of an explicit scheme and can be of arbitrary order in space and time. The construction is based on: (a) the representation of the system of conservation laws by a kinetic vectorial representation with a stiff relaxation term; (b) a matrix-free, CFL-less implicit discontinuous Galerkin transport solver; and (c) a stiffly accurate composition method for time integration. The method is validated on several one-dimensional test cases. It is then applied on two-dimensional and three-dimensional test cases: flow past a cylinder, magnetohydrodynamics and multifluid sedimentation

    Le droit à l’eau, soluble dans le droit international de l’investissement ?

    Get PDF
    International audienceOverprotection by ICSID* of international investments promotes the financing of the supply of drinking water infrastructure. But in maintaining an unbalanced relationship with the human right to water, does it not likely to turn against the interests of local populations? * International Centre for Settlement of Investment Disputes.La surprotection par le CIRDI* des investissements internationaux favorise le financement d’infrastructures d’approvisionnement en eau potable. Mais en entretenant un rapport dĂ©sĂ©quilibrĂ© avec le droit de l’Homme Ă  l’eau, ne risque-t-elle pas de se retourner contre les intĂ©rĂȘts des populations locales ? * Centre international pour le rĂšglement des diffĂ©rends relatifs aux investissements.La sovraprotezione per il CIRDI * degli investimenti internazionali favorisco il finanziamento di infrastrutture di approvvigionamento in acqua potabile. Ma intrattenendo un rapporto sbilanciato col diritto dell'uomo all'acqua, non rischia di ritorcersi contro gli interessi delle popolazioni locali ? * Centro internazionale per il regolamento delle controversie relative agli investimenti

    Spectral analysis of gene expression profiles using gene networks

    Full text link
    Microarrays have become extremely useful for analysing genetic phenomena, but establishing a relation between microarray analysis results (typically a list of genes) and their biological significance is often difficult. Currently, the standard approach is to map a posteriori the results onto gene networks to elucidate the functions perturbed at the level of pathways. However, integrating a priori knowledge of the gene networks could help in the statistical analysis of gene expression data and in their biological interpretation. Here we propose a method to integrate a priori the knowledge of a gene network in the analysis of gene expression data. The approach is based on the spectral decomposition of gene expression profiles with respect to the eigenfunctions of the graph, resulting in an attenuation of the high-frequency components of the expression profiles with respect to the topology of the graph. We show how to derive unsupervised and supervised classification algorithms of expression profiles, resulting in classifiers with biological relevance. We applied the method to the analysis of a set of expression profiles from irradiated and non-irradiated yeast strains. It performed at least as well as the usual classification but provides much more biologically relevant results and allows a direct biological interpretation

    Enrichissement de lexiques sémantiques approvisionnés par les foules : le systÚme WISIGOTH appliqué à Wiktionary

    Get PDF
    International audienceSemantic lexical resources are a mainstay of various NLP applications. However, comprehensive and reliable resources rarely exist or are often not freely available. We discuss in this paper the context of lexical resources building and the problems of evaluation. We present Wiktionary, a freely available and collaboratively built multilingual dictionary and we propose a semi-automatic approach based on random walks for enriching its synonymy network, which uses endogenous and exogenous data. We then propose a validation "by crowds". Finally, we present an implementation of this system called WISIGOTH.Bien que de nombreuses applications de TAL reposent sur des ressources lexicales sĂ©mantiques, celles-ci sont rarement simultanĂ©ment de qualitĂ© satisfaisante et librement disponibles. Partant de la confrontation entre mĂ©thodes traditionnelles et tendances Ă©mergentes de construction et d'Ă©valuation de ressources lexicales, nous prĂ©sentons dans cet article une nouvelle mĂ©thode fondĂ©e sur Wiktionary, un dictionnaire multilingue libre, disponible en ligne et construit collaborativement, puis nous proposons un enrichissement semi-automatique de son rĂ©seau de synonymie utilisant des donnĂ©es endogĂšnes et exogĂšnes, recourant Ă  une validation " par les foules ". Nous dĂ©crivons enïŹn une implĂ©mentation de ce systĂšme baptisĂ©e WISIGOTH
    • 

    corecore