Zhiwei Deng

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This paper presents a deep neural-network-based hierarchical graphical model for individual and group activity recognition in surveillance scenes. Deep networks are used to recognize the actions of individual people in a scene. Next, a neural-network-based hierarchical graphical model refines the predicted labels for each class by considering dependencies(More)
Human action categories exhibit significant intra-class variation. Changes in viewpoint, human appearance, and the temporal evolution of an action confound recognition algorithms. In order to address this, we present an approach to discover action primitives, sub-categories of action classes, that allow us to model this intra-class variation. We learn(More)
Rich semantic relations are important in a variety of visual recognition problems. As a concrete example, group activity recognition involves the interactions and relative spatial relations of a set of people in a scene. State of the art recognition methods center on deep learning approaches for training highly effective, complex classifiers for(More)
In group activity recognition, the temporal dynamics of the whole activity can be inferred based on the dynamics of the individual people representing the activity. We build a deep model to capture these dynamics based on LSTM (long short-term memory) models. To make use of these observations , we present a 2-stage deep temporal model for the group activity(More)
Chemical examination of the green alga Cladophora fascicularis resulted in the isolation and characterization of a new porphyrin derivative, porphyrinolactone (1), along with five known phaeophytins 2-6 and fourteen sterols and cycloartanes. The structure of 1 was determined on the basis of spectroscopic analyses and by comparison of its NMR data with those(More)
Chromatographic separation of the methanolic extract of the marine soft coral, Sinularia flexibilis, resulted in the isolation and characterization of four new sterols, 5alpha,8alpha-epidioxygorgosta-6-en-3beta-ol (1), 5alpha,8alpha-epidioxygorgosta-6,9(11)-dien-3beta-ol (2), 22alpha,28-epidioxycholesta-5,23(E)-dien-3beta-ol (3) and its C-22 epimer (4),(More)
The aim of this research was to determine the chemical composition and insecticidal activity of the essential oils derived from flowering aerial parts of Artemisia giraldii Pamp. and A. subdigitata Mattf. (Family: Asteraceae) against the maize weevil (Sitophilus zeamais Motsch.). Essential oils of aerial parts of A. giraldii and A. subdigitata were obtained(More)
The aim of this research was to determine chemical composition and insecticidal activity of the essential oil of Illicium pachyphyllum fruits against two grain storage insects, Sitophilus zeamais and Tribolium castaneum, and to isolate any insecticidal constituents from the essential oil. The essential oil of I. pachyphyllum fruits was obtained by(More)
Chemical examination of a Chinese soft coral Lobophytum pauciflorum resulted in the isolation of five new biscembranoids named lobophytones O-S (1-5) and a new "monomeric" cembrane lobophytone T (6). The structures of the new compounds were elucidated by interpretation of 1D and 2D NMR (COSY, HSQC, HMBC, and NOESY) spectroscopic data in association with MS(More)
Two new jaspamide derivatives 2 and 3, together with the parent compound jaspamide (1) have been isolated from the marine sponge Jaspis splendens collected in Kalimantan (Indonesia). The structures of the new compounds were unambiguously elucidated based on 1D and 2D NMR spectral data, mass spectrometry and comparison with jaspamide (1). The new derivatives(More)