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Skeleton-based human action recognition is attracting more attention in computer vision.Recently,graph convolutional networks(GCNs),which is powerful to model non-Euclidean structure data,have obtained promising performance and enable a new paradigm for action recognition.Existing approaches mostly model the spatial dependency with emphasis mechanism since the huge pre-defined graph contains large quantities of noise.However,simply emphasizing subsets is not optimal for reflecting the dynamic underlying correlations between vertexes in a global manner.Furthermore,these methods are ineffective to capture the temporal dependencies as the CNNs or RNNs are not capable to model the intricate multi-range temporal relations.To address these issues,a multi-scale gated graph convolutional network (MSG-GCN) is proposed for skeleton-based action recognition.Specifically,a gated temporal convolution module (G-TCM) is presented to capture the consecutive short-term and interval long-term dependencies between vertexes in the temporal domain.Besides,a multi-dimensional attention module for spatial,temporal,and channel,which enhances the expressiveness of spatial graph,is integrated into GCNs with negligible overheads.Extensive experiments on two large-scale benchmark datasets,NTU-RGB+D and Kinetics,demonstrate that our approach outperforms the state-of-the-art baselines.

The study of facile‐synthesis and low‐cost X‐ray scintillators with high light yield, low detection limit and high X‐ray imaging resolution plays a vital role in medical and industrial imaging fields. However, the optimal balance between X‐ray absorption, decay lifetime and excitonic utilization efficiency of scintillators to achieve high‐resolution imaging is extremely difficult due to the inherent contradiction. Here two thermally activated delayed fluorescence (TADF)‐actived coinage‐metal clusters M6S6L6 (M=Ag or Cu) were synthesized by simple solvothermal reaction, where the cooperation of heavy atom‐rich character and TADF mechanism supports strong X‐ray absorption and rapid luminescent collection of excitons. Excitingly, Ag6S6L6 (SC‐Ag) displays a high photoluminescence quantum yield of 91.6 % and scintillating light yield of 17420 photons MeV−1, as well as a low detection limit of 208.65 nGy s−1 that is 26 times lower than the medical standard (5.5 μGy s−1). More importantly, a high X‐ray imaging resolution of 16 lp/mm based on SC‐Ag screen is demonstrated. Besides, rigid core skeleton reinforced by metallophilicity endows clusters M6S6L6 strong resistance to humidity and radiation. This work provides a new view for the design of efficient scintillators and opens the research door for silver clusters in scintillation application. [ABSTRACT FROM AUTHOR]