48,094 research outputs found

    M-theory Inspired No-scale Supergravity

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    We propose a supergravity model that contains elements recently shown to arise in the strongly-coupled limit of the E8Ă—E8E_8\times E_8 heterotic string (M-theory), including a no-scale--like K\"ahler potential, the identification of the string scale with the gauge coupling unification scale, and the onset of supersymmetry breaking at an intermediate scale determined by the size of the eleventh dimension of M-theory. We also study the phenomenological consequences of such scenario, which include a rather constrained sparticle spectrum within the reach of present-generation particle accelerators.Comment: 8 pages, LaTeX, 3 figures (included

    Matrix elements of four-quark operators and \Delta L=2 hyperon decays

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    The study of neutrinoless double beta decays of nuclei and hyperons require the calculation of hadronic matrix elements of local four-quark operators that change the total charge by two units \Delta Q=2 . Using a low energy effective Lagrangian that induces these transitions, we compute these hadronic matrix elements in the framework of the MIT bag model. As an illustrative example we evaluate the amplitude and transition rate of \Sigma- -> p e- e-, a decay process that violates lepton number by two units (\Delta L=2). The relevant matrix element is evaluated without assuming the usual factorization approximation of the four-quark operators and the results obtained in both approaches are compared.Comment: 13 pages, 2 .eps figure

    Effects of typhoons on gelatinous carnivore zooplankton off Northern Taiwan

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    We examine the effect of typhoons, as potential drivers of nutrient pulse events, on gelatinous carnivore zooplankton. The period investigated spanned from 2007 to 2010, where seasonal abundance and taxonomic composition of the gelatinous zooplankton community was recorded off North Taiwan. Typhoon effects were assessed in the abundance, diversity and species richness of the gelatinous carnivore populations. Significant associations between typhoons and gelatinous carnivores were found in time delays varying from 3 to 25 days, but no association was identified for longer time intervals. Generally, a decrease in species richness occurred during the summer season, and this was accentuated in 2008, shortly after typhoons events. We hypothesize that typhoons might act as resource pulse triggers probably enhancing open niches for opportunistic carnivore zooplankton groups

    Attention-Based Models for Text-Dependent Speaker Verification

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    Attention-based models have recently shown great performance on a range of tasks, such as speech recognition, machine translation, and image captioning due to their ability to summarize relevant information that expands through the entire length of an input sequence. In this paper, we analyze the usage of attention mechanisms to the problem of sequence summarization in our end-to-end text-dependent speaker recognition system. We explore different topologies and their variants of the attention layer, and compare different pooling methods on the attention weights. Ultimately, we show that attention-based models can improves the Equal Error Rate (EER) of our speaker verification system by relatively 14% compared to our non-attention LSTM baseline model.Comment: Submitted to ICASSP 201
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