67 research outputs found

    Multi-access Coded Caching with Optimal Rate and Linear Subpacketization under PDA and Consecutive Cyclic Placement

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    This work considers the multi-access caching system proposed by Hachem et al., where each user has access to L neighboring caches in a cyclic wrap-around fashion. We first propose a placement strategy called the consecutive cyclic placement, which achieves the maximal local caching gain. Then under the consecutive cyclic placement, we derive the optimal coded caching gain from the perspective of Placement Delivery Array (PDA), thus obtaining a lower bound on the rate of PDA. Finally, under the consecutive cyclic placement, we construct a class of PDA, leading to a multi-access coded caching scheme with linear subpacketization, which achieves our derived lower bound for some parameters; while for other parameters, the achieved coded caching gain is only 1 less than the optimal one. Analytical and numerical comparisons of the proposed scheme with existing schemes are provided to validate the performance.Comment: 30 pages, 7 figure

    TOPICAL REVIEW Luminescent nanomaterials for biological labelling

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    Abstract The use of labelling or staining agents has greatly assisted the study of complex biological interactions in the field of biology. In particular, fluorescent labelling of biomolecules has been demonstrated as an indispensable tool in many biological studies. Types of fluorescent labelling agents that are commonly used include conventional classes of organic fluorophores such as fluorescein and cyanine dyes, as well as newer types of inorganic nanoparticles such as QDs, and novel fluorescent latex/silica nanobeads. The newer classes of fluorescent labels are gaining increasing popularity in place of their predecessors due to their better optical properties such as possessing an enhanced photostability and a larger Stokes shift over conventional organic fluorophores, for example. This paper gives an overview of the recent advances on these luminescent nanomaterials with emphases on their optical characteristics that are crucial in fluorescence microscopy, both advantages and limitations in their usage as well as challenges they face, and puts forward the future direction of fluorescent labels in the area of biolabelling

    Tunable van Hove singularity without structural instability in Kagome metal CsTi3_3Bi5_5

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    In Kagome metal CsV3_3Sb5_5, multiple intertwined orders are accompanied by both electronic and structural instabilities. These exotic orders have attracted much recent attention, but their origins remain elusive. The newly discovered CsTi3_3Bi5_5 is a Ti-based Kagome metal to parallel CsV3_3Sb5_5. Here, we report angle-resolved photoemission experiments and first-principles calculations on pristine and Cs-doped CsTi3_3Bi5_5 samples. Our results reveal that the van Hove singularity (vHS) in CsTi3_3Bi5_5 can be tuned in a large energy range without structural instability, different from that in CsV3_3Sb5_5. As such, CsTi3_3Bi5_5 provides a complementary platform to disentangle and investigate the electronic instability with a tunable vHS in Kagome metals

    Human Resources for Health Development Policy: A comparison between China and India

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    Journal of Asian Public Policy153411-43

    Grey forecast model for torpedo development cost based on neural network

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    1621-1626Cumulative curve of development cost for torpedo shows similar to shape S. Then grey Verhulst model of development cost for torpedo can be established by collecting the development cost historical data for several years. The fitted values and the predictive value can be gotten. To take full advantage of information contains in the historical data, a mapping between historical data and the predictive value using BP neural networks can be found through BP Neural Networks. Example shows that this method has good prediction accuracy
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