6,624 research outputs found

    A brief network analysis of Artificial Intelligence publication

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    In this paper, we present an illustration to the history of Artificial Intelligence(AI) with a statistical analysis of publish since 1940. We collected and mined through the IEEE publish data base to analysis the geological and chronological variance of the activeness of research in AI. The connections between different institutes are showed. The result shows that the leading community of AI research are mainly in the USA, China, the Europe and Japan. The key institutes, authors and the research hotspots are revealed. It is found that the research institutes in the fields like Data Mining, Computer Vision, Pattern Recognition and some other fields of Machine Learning are quite consistent, implying a strong interaction between the community of each field. It is also showed that the research of Electronic Engineering and Industrial or Commercial applications are very active in California. Japan is also publishing a lot of papers in robotics. Due to the limitation of data source, the result might be overly influenced by the number of published articles, which is to our best improved by applying network keynode analysis on the research community instead of merely count the number of publish.Comment: 18 pages, 7 figure

    Search for C=+C=+ charmonium and XYZ states in e+eγ+He^+e^-\to \gamma+ H at BESIII

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    Within the framework of nonrelativistic quantum chromodynamics, we study the production of C=+C=+ charmonium states HH in e+eγ + He^+e^-\to \gamma~+~H at BESIII with H=ηc(nS)H=\eta_c(nS) (n=1, 2, 3, and 4), χcJ(nP)\chi_{cJ}(nP) (n=1, 2, and 3), and 1D2(nD)^1D_2(nD) (n=1 and 2). The radiative and relativistic corrections are calculated to next-to-leading order for SS and PP wave states. We then argue that the search for C=+C=+ XYZXYZ states such as X(3872)X(3872), X(3940)X(3940), X(4160)X(4160), and X(4350)X(4350) in e+eγ + He^+e^-\to \gamma~+~H at BESIII may help clarify the nature of these states. BESIII can search XYZXYZ states through two body process e+eγHe^+e^-\to \gamma H, where HH decay to J/ψπ+πJ/\psi \pi^+\pi^-, J/ψϕJ/\psi \phi, or DDˉD \bar D. This result may be useful in identifying the nature of C=+C=+ XYZXYZ states. For completeness, the production of C=+C=+ charmonium in e+eγ+ He^+e^-\to \gamma +~H at B factories is also discussed.Comment: Comments and suggestions are welcome. References are update

    Optimization of Analytic Window Functions

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    Analytic functions represent the state-of-the-art way of performing complex data analysis within a single SQL statement. In particular, an important class of analytic functions that has been frequently used in commercial systems to support OLAP and decision support applications is the class of window functions. A window function returns for each input tuple a value derived from applying a function over a window of neighboring tuples. However, existing window function evaluation approaches are based on a naive sorting scheme. In this paper, we study the problem of optimizing the evaluation of window functions. We propose several efficient techniques, and identify optimization opportunities that allow us to optimize the evaluation of a set of window functions. We have integrated our scheme into PostgreSQL. Our comprehensive experimental study on the TPC-DS datasets as well as synthetic datasets and queries demonstrate significant speedup over existing approaches.Comment: VLDB201
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