To improve the recognition performance of video human actions,an approach that models the video actions in a hierarchical way is proposed. This hierarchical model summarizes the action contents with different spatio-t...To improve the recognition performance of video human actions,an approach that models the video actions in a hierarchical way is proposed. This hierarchical model summarizes the action contents with different spatio-temporal domains according to the properties of human body movement.First,the temporal gradient combined with the constraint of coherent motion pattern is utilized to extract stable and dense motion features that are viewed as point features,then the mean-shift clustering algorithm with the adaptive scale kernel is used to label these features.After pooling the features with the same label to generate part-based representation,the visual word responses within one large scale volume are collected as video object representation.On the benchmark KTH（Kungliga Tekniska H？gskolan）and UCF （University of Central Florida）-sports action datasets,the experimental results show that the proposed method enhances the representative and discriminative power of action features, and improves recognition rates.Compared with other related literature,the proposed method obtains superior performance.展开更多
The MS6.4 Menyuan earthquake occurred on the northern side of the Lenglongling fault(LLLF) in the mid-western of the Qilian-Haiyuan fault zone on January 21, 2016. The earthquake epicenter was distant from the Minle-D...The MS6.4 Menyuan earthquake occurred on the northern side of the Lenglongling fault(LLLF) in the mid-western of the Qilian-Haiyuan fault zone on January 21, 2016. The earthquake epicenter was distant from the Minle-Damaying and Huangcheng-Shuangta faults, eastern of the Northern Qilian Shan fault zone. A near northwest-striking rupture plane intersects the two faults at a certain angle. The focal mechanism solution shows that this was a thrust-type earthquake, slightly different from the strike-slip movement with a thrust component of the LLLF. Field geological mapping, tectonic geomorphology analysis, trench excavation and 14 C dating reveal that(1) the LLLF has been obviously active since the Holocene, and may behave with characteristic slip behavior and produce M_W7.3–7.5 earthquakes;(2) the LLLF appears as a flower structure in terms of structure style, and dips NNE at a steep angle; and(3) the most recent earthquake event occurred after 1815–1065 a BP. An associated fault, the Northern Lenglongling fault(NLLLF), is located at the northwestern end of the LLLF. Consequently, the NLLLF was continually subject to tectonic pushing effects from the left-lateral shear at the end of the LLLF, and, accordingly, it bent and rotated outward tectonically.Subsequently, the fault deviated from the dominant rupture azimuth and activity weakened. In the late Quaternary, it behaved as a thrust fault with no obvious deformation at the surface. This is indicated by the arc shape, with a micro-protrusion northeastward,and no geologic or geomorphic signs of surface rupturing since the late Quaternary. However, such faults could still rupture at depth, producing moderate-strong earthquakes. The geometric and kinematic properties of the NLLLF are in good agreement with the occurrence and kinematic properties of nodal plane 2, and with the distribution characteristics of the aftershocks and seismic intensity. Therefore, the NLLLF is a more suitable seismogenic structure for the MS 6.4 Menyuan earthquake. In addition, the thrust movement of the NLLLF accommodates subsequent movement of the LLLF. During the historical evolution of the NLLLF,the LLLF and the NLLLF have affected the local topography through tectonic uplift.展开更多
基金The National Natural Science Foundation of China(No.60971098,61201345)
文摘To improve the recognition performance of video human actions,an approach that models the video actions in a hierarchical way is proposed. This hierarchical model summarizes the action contents with different spatio-temporal domains according to the properties of human body movement.First,the temporal gradient combined with the constraint of coherent motion pattern is utilized to extract stable and dense motion features that are viewed as point features,then the mean-shift clustering algorithm with the adaptive scale kernel is used to label these features.After pooling the features with the same label to generate part-based representation,the visual word responses within one large scale volume are collected as video object representation.On the benchmark KTH（Kungliga Tekniska H？gskolan）and UCF （University of Central Florida）-sports action datasets,the experimental results show that the proposed method enhances the representative and discriminative power of action features, and improves recognition rates.Compared with other related literature,the proposed method obtains superior performance.
基金supported by a Special Project on Earthquake Research, the China Active Fault Survey Project-The South-North Seismic Zone Northern Segment (Grant No. 201408023)Fundamental Research Funds in Institute of Crustal Dynamics, China Earthquake Administration (Grant No. ZDJ2015-16)
文摘The MS6.4 Menyuan earthquake occurred on the northern side of the Lenglongling fault(LLLF) in the mid-western of the Qilian-Haiyuan fault zone on January 21, 2016. The earthquake epicenter was distant from the Minle-Damaying and Huangcheng-Shuangta faults, eastern of the Northern Qilian Shan fault zone. A near northwest-striking rupture plane intersects the two faults at a certain angle. The focal mechanism solution shows that this was a thrust-type earthquake, slightly different from the strike-slip movement with a thrust component of the LLLF. Field geological mapping, tectonic geomorphology analysis, trench excavation and 14 C dating reveal that(1) the LLLF has been obviously active since the Holocene, and may behave with characteristic slip behavior and produce M_W7.3–7.5 earthquakes;(2) the LLLF appears as a flower structure in terms of structure style, and dips NNE at a steep angle; and(3) the most recent earthquake event occurred after 1815–1065 a BP. An associated fault, the Northern Lenglongling fault(NLLLF), is located at the northwestern end of the LLLF. Consequently, the NLLLF was continually subject to tectonic pushing effects from the left-lateral shear at the end of the LLLF, and, accordingly, it bent and rotated outward tectonically.Subsequently, the fault deviated from the dominant rupture azimuth and activity weakened. In the late Quaternary, it behaved as a thrust fault with no obvious deformation at the surface. This is indicated by the arc shape, with a micro-protrusion northeastward,and no geologic or geomorphic signs of surface rupturing since the late Quaternary. However, such faults could still rupture at depth, producing moderate-strong earthquakes. The geometric and kinematic properties of the NLLLF are in good agreement with the occurrence and kinematic properties of nodal plane 2, and with the distribution characteristics of the aftershocks and seismic intensity. Therefore, the NLLLF is a more suitable seismogenic structure for the MS 6.4 Menyuan earthquake. In addition, the thrust movement of the NLLLF accommodates subsequent movement of the LLLF. During the historical evolution of the NLLLF,the LLLF and the NLLLF have affected the local topography through tectonic uplift.
