著者

Tsugawa Sho Ohsaki Hiroyuki

出版者

Public Library of Science

雑誌

PLoS ONE (ISSN:19326203)

巻号頁・発行日

vol.8, no.12, pp.e81727, 2013-12

被引用文献数

5 3

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Research on link prediction for social networks has been actively pursued. In link prediction for a given social network obtained from time-windowed observation, new link formation in the network is predicted from the topology of the obtained network. In contrast, recent advances in sensing technology have made it possible to obtain face-to-face behavioral networks, which are social networks representing face-to-face interactions among people. However, the effectiveness of link prediction techniques for face-to-face behavioral networks has not yet been explored in depth. To clarify this point, here we investigate the accuracy of conventional link prediction techniques for networks obtained from the history of face-to-face interactions among participants at an academic conference. Our findings were (1) that conventional link prediction techniques predict new link formation with a precision of 0.30–0.45 and a recall of 0.10–0.20, (2) that prolonged observation of social networks often degrades the prediction accuracy, (3) that the proposed decaying weight method leads to higher prediction accuracy than can be achieved by observing all records of communication and simply using them unmodified, and (4) that the prediction accuracy for face-to-face behavioral networks is relatively high compared to that for non-social networks, but not as high as for other types of social networks.

著者

Xu Dehong Baba Junpei Masada Eisuke OHSAKI Hiroyuki

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌. D, 産業応用部門誌 = The transactions of the Institute of Electrical Engineers of Japan. D, A publication of Industry Applications Society (ISSN:09136339)

巻号頁・発行日

vol.118, no.4, pp.518-524, 1998-04

被引用文献数

1 2

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A novel multi modular GTO current source converter structure is presented to application to superconducting magnetic energy storage system. N_??_N converters are arranged in a array form. The GTO current source converter array with appropriate arrangement of modulation and carrier signals can output large power with high quality line current waveforms. With using of only <i>N</i> transformers, 6N² pulse number converter performance is obtained. Only low switching of GTO is required since PWM is primarily used as a method to control flow of power instead of reducing harmonics. It is compared with conventional direct paralleled multi modular converter structure. The results of simulation are presented in this paper.