5,729 research outputs found

    Hard X-ray emission cutoff in anomalous X-ray pulsar 4U 0142+61 detected by INTEGRAL

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    The anomalous X-ray pulsar 4U 0142+61 was studied by the INTEGRAL observations. The hard X-ray spectrum of 18 -- 500 keV for 4U 0142+61 was derived using near 9 years of INTEGRAL/IBIS data. We obtained the average hard X-ray spectrum of 4U 0142+61 with all available data. The spectrum of 4U 0142+61 can be fitted with a power-law with an exponential high energy cutoff. This average spectrum is well fitted with a power-law of Γ0.51±0.11\Gamma\sim 0.51\pm 0.11 plus a cutoff energy at 128.6±17.2128.6\pm 17.2 keV. The hard X-ray flux of the source from 20 -- 150 keV showed no significant variations (within 20%\%) from 2003 -- 2011. The spectral profiles have some variability in nine years: photon index varied from 0.3 -- 1.5, and cutoff energies of 110 -- 250 keV. The detection of the high energy cutoff around 130 keV shows some constraints on the radiation mechanisms of magnetars and possibly probes the differences between magnetar and accretion models for these special class of neutron stars. Future HXMT observations could provide stronger constraints on the hard X-ray spectral properties of this source and other magnetar candidates.Comment: 9 pages, 5 figures, 2 tables, figures are updated, new data are added, conclusion does not change, to be published in RA

    Study of blasting vibration safety security criterion method based on response spectrum

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    AbstractBased on lots of blasting vibration monitoring data, correlation analysis on blasting vibration velocity response spectrum SR and blasting seismic waves with each signal characteristic, research that SR has damage and associated influence on building structure vibration. Research found that SR can reflect the values of the comprehensive effect of blasting vibration, and the dynamic characteristics of the influence of structural vibration. According to the research results, this paper puts forward with SR as blasting vibration safety assessment criterion of new methods

    Concurrence-Aware Long Short-Term Sub-Memories for Person-Person Action Recognition

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    Recently, Long Short-Term Memory (LSTM) has become a popular choice to model individual dynamics for single-person action recognition due to its ability of modeling the temporal information in various ranges of dynamic contexts. However, existing RNN models only focus on capturing the temporal dynamics of the person-person interactions by naively combining the activity dynamics of individuals or modeling them as a whole. This neglects the inter-related dynamics of how person-person interactions change over time. To this end, we propose a novel Concurrence-Aware Long Short-Term Sub-Memories (Co-LSTSM) to model the long-term inter-related dynamics between two interacting people on the bounding boxes covering people. Specifically, for each frame, two sub-memory units store individual motion information, while a concurrent LSTM unit selectively integrates and stores inter-related motion information between interacting people from these two sub-memory units via a new co-memory cell. Experimental results on the BIT and UT datasets show the superiority of Co-LSTSM compared with the state-of-the-art methods