6,073 research outputs found

    Analysis and Research on Factors Affecting Information Dissemination of Emergencies in Social Media Environment

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    We examine whether emotional expression (joy, anger, sadness, fear, disgust) occurring in social media content is associated with a user’s information sharing behavior. Our research is in the context of Hurricane Irma and Tweets associated with that event. We find that negative emotions play an important role in the communication of information, among which, fear has the most significant effect. Meanwhile, the initial stages of the information life cycle have the most prominent influence on the information dissemination

    A Semantic Graph-Based Approach for Mining Common Topics From Multiple Asynchronous Text Streams

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    In the age of Web 2.0, a substantial amount of unstructured content are distributed through multiple text streams in an asynchronous fashion, which makes it increasingly difficult to glean and distill useful information. An effective way to explore the information in text streams is topic modelling, which can further facilitate other applications such as search, information browsing, and pattern mining. In this paper, we propose a semantic graph based topic modelling approach for structuring asynchronous text streams. Our model in- tegrates topic mining and time synchronization, two core modules for addressing the problem, into a unified model. Specifically, for handling the lexical gap issues, we use global semantic graphs of each timestamp for capturing the hid- den interaction among entities from all the text streams. For dealing with the sources asynchronism problem, local semantic graphs are employed to discover similar topics of different entities that can be potentially separated by time gaps. Our experiment on two real-world datasets shows that the proposed model significantly outperforms the existing ones

    Cosmology-independent Estimate of the Fraction of Baryon Mass in the IGM from Fast Radio Burst Observations

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    The excessive dispersion measure (DM) of fast radio bursts (FRBs) has been proposed to be a powerful tool to study intergalactic medium (IGM) and to perform cosmography. One issue is that the fraction of baryons in the IGM, f IGM, is not properly constrained. Here, we propose a method of estimating f IGM using a putative sample of FRBs with the measurements of both DM and luminosity distance d L. The latter can be obtained if the FRB is associated with a distance indicator (e.g., a gamma-ray burst or a gravitational-wave event), or the redshift z of the FRB is measured and d L at the corresponding z is available from other distance indicators (e.g., SNe Ia) at the same redshift. As d L/DM essentially does not depend on cosmological parameters, our method can determine f IGM independent of cosmological parameters. We parameterize f IGM as a function of redshift and model the DM contribution from a host galaxy as a function of star formation rate. Assuming f IGM has a mild evolution with redshift with a functional form and by means of Monte Carlo simulations, we show that an unbiased and cosmology-independent estimate of the present value of f IGM with a ~12% uncertainty can be obtained with 50 joint measurements of d L and DM. In addition, such a method can also lead to a measurement of the mean value of DM contributed from the local host galaxy

    Grey Correlation Analysis on the Total Amount of Power Consumption and That of Different Industries in China

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    Abstract: This study has made deep research on the relationship between the total amount of power consumption and that of different industries in China from 2000 to 2009. On this basis, the grey correlation degrees between the total amount of power consumption and that of different industries have been calculated by applying grey correlation method, so that we can know the different effects that each industry has had on the total power consumption. Finally, this study set up a grey correlation model GM (1, n) to forecast China's total amount of power consumption

    Electronic Structure in Gapped Graphene with Coulomb Potential

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    In this paper, we numerically study the bound electron states induced by long range Coulomb impurity in gapped graphene and the quasi-bound states in supercritical region based on the lattice model. We present a detailed comparison between our numerical simulations and the prediction of the continuum model which is described by the Dirac equation in (2+1)-dimensional Quantum Electrodynamics (QED). We also use the Fano's formalism to investigate the quasi-bound state development and design an accessible experiments to test the decay of the supercritical vacuum in the gapped graphene.Comment: 5 page, 4 figure
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