Limin Wang
共找到 17 条论著文献

1、Recurrent Stroke in Minor Ischemic Stroke or Transient Ischemic Attack With Metabolic Syndrome and/or Diabetes Mellitu

2、MoFAP: A Multi-level Representation for Action Recognition

摘要:This paper proposes a multi-level video representation by stacking the activations of motion features, atoms, and phrases (MoFAP). Motion features refer to those low-level local descriptors, while motion atoms and phrases can be viewed as mid-level 「temporal parts」. Motion atom is defined as an atomic part of action, and captures the motion information of video in a short temporal scale. Motion phrase is a temporal composite of multiple motion atoms defined with an AND/OR structure. It further enhances the discriminative capacity of motion atoms by incorporating temporal structure in a longer temporal scale. Specifically, we first design a discriminative clustering method to automatically discover a set of representative motion atoms. Then, we mine effective motion phrases with high discriminative and representative capacity in a bottom-up manner. Based on these basic units of motion features, atoms, and phrases, we construct a MoFAP network by stacking them layer by layer. This MoFAP network enables us to extract the effective representation of video data from different levels and scales. The separate representations from motion features, motion atoms, and motion phrases are concatenated as a whole one, called Activation of MoFAP. The effectiveness of this representation is demonstrated on four challenging datasets: Olympic Sports, UCF50, HMDB51, and UCF101. Experimental results show that our representation achieves the state-of-the-art performance on these datasets.
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3、A PTAS for the minimum weight connected vertex cover P 3 problem on unit disk graph

摘要:Let G = ( V , E ) be a weighted graph, i.e., with a vertex weight function w : V → R + . We study the problem of determining a minimum weight connected subgraph of G that has at least one vertex in common with all paths of length two in G. It is known that this problem is NP-hard for general graphs. We first show that it remains NP-hard when restricted to unit disk graphs. Our main contribution is a polynomial time approximation scheme for this problem if we assume that the problem is c-local and the unit disk graphs have minimum degree of at least two.
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4、The spindle function of CDCA4

摘要:In an attempt to discover novel proteins functioning in both interphase nucleus and mitotic spindle as NuMA does, we carried out cDNA library screening with pooled autoimmune antibodies. Among positive clones we found a recently identified transcription regulatory protein (CDCA4) with the distinctive nuclear-mitotic apparatus distribution. CDCA4 localizes at metaphase spindle poles and the midzone in later stages. Additionally, an intensive CDCA4 accumulation parallel to spindle was observed in half of metaphase cells but not in later stages, implying a transient form of CDCA4 binding to midzone from anaphase. Mitotic arrest dissolved CDCA4 from centrosomes but during the spindle recovery, CDCA4 invariably colocalized with the microtubule nucleation foci as a component of microtubule organization center. RNA interference of CDCA4 resulted in significant increase of multinuclei and multipolar spindles, suggesting impaired function in chromosome segregation or cytokinesis. However, the spindle checkpoint and the centrosome cycle appeared not to be affected by such interference. Furthermore, CDCA4 depletion resulted in accelerated cell proliferation, perhaps due to the disruption of CDCA4 nuclear function as a transcription suppressor. Interphase CDCA4 is localized in nucleoli by immunofluorescence, although GFP-CDCA4 expressed in the nucleoplasm. An N-terminal KRKC domain appears to be the nuclear localization signal as identified by sequence alignment and the expression of truncated mutants. Taken together, our results suggested that as a novel nuclearmitotic apparatus protein, CDCA4 is involved in spindle organization from prometaphase. When anaphase begins, CDCA4 may play a different role as a midzone factor involved in chromosome segregation or cytokinesis. Cell Motil. Cytoskeleton 2008. © 2008 Wiley-Liss, Inc.
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5、Trade and investment in China : the European experience 1998

摘要:從書:Routledge studies in the growth economies of Asia. xviii, 315 pages : illustrations ; 24 cm. This new study examines the economic relationship between China and Europe, its importance and how it is likely to evolve and includes case studies of the automobile, toy, watch, telecommunications, banking and insurance industries.  再讀一些...
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6、A New Cubic Phase for a NaYF ₄ Host Matrix Offering High Upconversion Luminescence Efficiency

7、Video Action Detection with Relational Dynamic-Poselet

摘要:Action detection is of great importance in understanding human motion from video. Compared with action recognition, it not only recognizes action type, but also localizes its spatiotemporal extent. This paper presents a relational model for action detection, which first decomposes human action into temporal 「key poses」 and then further into spatial 「action parts」. Specifically, we start by clustering cuboids around each human joint into dynamic-poselets using a new descriptor. The cuboids from the same cluster share consistent geometric and dynamic structure, and each cluster acts as a mixture of body parts. We then propose a sequential skeleton model to capture the relations among dynamic-poselets. This model unifies the tasks of learning the composites of mixture dynamic-poselets, the spatiotemporal structures of action parts, and the local model for each action part in a single framework. Our model not only allows to localize the action in a video stream, but also enables a detailed pose estimation of an actor. We formulate the model learning problem in a structured SVM framework and speed up model inference by dynamic programming. We conduct experiments on three challenging action detection datasets: the MSR-II dataset, the UCF Sports dataset, and the JHMDB dataset. The results show that our method achieves superior performance to the state-of-the-art methods on these datasets.
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8、Temporal Segment Networks: Towards Good Practices for Deep Action Recognition

摘要:Deep convolutional networks have achieved great success for visual recognition in still images. However, for action recognition in videos, the advantage over traditional methods is not so evident. This paper aims to discover the principles to design effective ConvNet architectures for action recognition in videos and learn these models given limited training samples. Our first contribution is temporal segment network (TSN), a novel framework for video-based action recognition. which is based on the idea of long-range temporal structure modeling. It combines a sparse temporal sampling strategy and video-level supervision to enable efficient and effective learning using the whole action video. The other contribution is our study on a series of good practices in learning ConvNets on video data with the help of temporal segment network. Our approach obtains the state-the-of-art performance on the datasets of HMDB51 ( ) and UCF101 ( ). We also visualize the learned ConvNet models, which qualitatively demonstrates the effectiveness of temporal segment network and the proposed good practices (Models and code at https://github.com/yjxiong/temporal-segment-networks ).
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9、Alcohol consumption and work-related injuries among farmers in Heilongjiang Province, People's Republic of China

摘要:Background: Alcohol consumption has been found to be associated with work-related injuries among workers around the world, but this association has not well been studied among agricultural workers in China.Methods: This population-based survey aimed to study the association between alcohol use and work-related agricultural injury. Farmers in a northeastern province of China were questioned about work-related injury in the past year (May 2007-April 2008), alcohol use, farming practices, and sociodemographic factors. The Chi-square test and logistic regression analyses were used to investigate the role of alcohol drinking in agricultural injuries.Results: Among 2,050 farmers who completed the survey, the 12-month prevalence of work-related injury was 12.2%. The leading external cause of injury was exposure to mechanical force. The odds of injury among farmers with past month drinking, who drank distilled spirits, and reported intoxication were respectively 1.77 (95% CI = 1.27-2.47), 1.89 (95% CI = 1.35-2.66), 2.12 (95% CI = 1.42-3.11). The odds of injury also significantly increased with greater average amounts of pure alcohol per day, with increased frequency of drinking per week, and with greater reported years of drinking. Each alcohol use variable was associated with injury in logistic regression models while controlling for sex, age, years of farm work, months of farm work in the past 12 months, driving a motor vehicle, and agricultural machinery use.Conclusions: We found a significant association between alcohol consumption and work-related injuries among farmers. Our findings stress the need for culturally appropriate interventions which affect alcohol use and prevent injuries among Chinese farmers. Am. J. Ind. Med. 53:825-835, 2010. © 2010 Wiley-Liss, Inc.
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10、The quality of growth and poverty reduction in China 2014

11、Protective Effects of Ginsenosides against Bisphenol A-Induced Cytotoxicity in 15P-1 Sertoli Cells via Extracellular Signal-Regulated Kinase 1/2 Signalling and Antioxidant Mechanism

12、A New Cubic Phase for a NaYF₄ Host Matrix Offering High Upconversion Luminescence Efficiency

摘要:A NaYF₄ host matrix with a new cubic phase is fabricated to offer high upconversion luminescence efficiency. The new cubic phase is formed through a hexagonal-to-cubic phase transition by shining intense near-infrared light on lanthanide-doped hexagonal NaYF₄ materials.
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13、Research on scheduling problems with general effects of deterioration and learning

摘要:Jobs with deterioration and learning effect co-exist in many industry engineering and logistics management situations. In this note, the general effects of deterioration and learning are considered. It is proved that some single machine scheduling problems are still polynomially solvable under the proposed model. The note also shows that some results in Lee and Lai’s recent paper (Lee and Lai, 2011) are incorrect by a counterexample.
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14、Design of fuzzy iterative learning fault-tolerant control for batch processes with time-varying delay

摘要:In this paper, a new two-dimensional (2D) fuzzy composite iterative learning fault-tolerant control strategy using a 2D Takagi-Sugeno fuzzy model is proposed for batch processes with time delay and actuator faults. Firstly, based on the local-sector nonlinearity method, a 2D Takagi-Sugeno fuzzy model representing the nonlinear batch process with actuator faults is constructed with a series of linear models and nonlinear membership functions. Then, a 2D fuzzy feedback control-based iterative learning fault-tolerant control strategy is proposed under the constructed model. Using the 2D Lyapunov stability theory, sufficient conditions for system asymptotic stability are given. The fault-tolerant control law is then designed, guaranteeing system asymptotic stability along time and batches even if the system fails. Finally, the traditional control algorithm, the pure iterative learning control algorithm, and the feedback control-based iterative learning control algorithm proposed in this paper are compared on the level control of the three-tank system, which proves the effectiveness of the proposed method.
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15、A PTAS for minimum weighted connected vertex cover

摘要:Given a connected and weighted graph G = ( V , E ) with each vertex v having a nonnegative weight w(v), the minimum weighted connected vertex cover P 3 problem ( M W C V C P 3 ) is required to find a subset C of vertices of the graph with minimum total weight, such that each path with length 2 has at least one vertex in C, and moreover, the induced subgraph G[C] is connected. This kind of problem has many applications concerning wireless sensor networks and ad hoc networks. When homogeneous sensors are deployed into a three-dimensional space instead of a plane, the mathematical model for the sensor network is a unit ball graph instead of a unit disk graph. In this paper, we propose a new concept called weak c-local and give the first polynomial time approximation scheme (PTAS) for M W C V C P 3 in unit ball graphs when the weight is smooth and weak c-local.
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16、Absolute configurations and CD spectra of axially chiral biphenyls prepared in a facile manner by crystallization-induced configuration transformation

摘要:Axially chiral biphenyls such as (M,S)-3k have been conveniently obtained by crystallization of their diastereomeric mixtures, which were synthesized from racemic 4,4′-dimethoxy-5,6,5′,6′-bis(methylenedioxy)-2-carboxylester-2′-carboxyl-biphenyls 4 and chiral amino alcohols (R)-alaninol, (S)-alaninol, (S)-valinol, and (S)-phenylalaninol. A crystallization-induced configuration transformation of the biphenyls was thus achieved. It was found that amide formation of an (S)-valinol or (S)-phenylalaninol at the 2′-position of the biphenyl usually induced the deposition of crystals with the (M)-configuration from ethanol in yields higher than 50%. The absolute configurations (ACs) of two crystalline biphenyls have been determined by X-ray crystallographic analysis. The ACs of nine biphenyls have been assigned based on their CD spectra. Further, stability investigation of these axially chiral biphenyls revealed that the ACs could revert upon redissolution. The energy barrier to epimerization between (P,R)-3b and (M,R)-3b was measured as ΔG# = 21.45 kcal/mol and the half-life in ethanol at 301 K was 17.1 h. Chirality, 2010. © 2010 Wiley-Liss, Inc.
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17、Lattice Boltzmann based discrete simulation for gas-solid fluidization

摘要:Discrete particle simulation, a combined approach of computational fluid dynamics and discrete methods such as DEM (discrete element method), DSMC (direct simulation Monte Carlo), SPH (smoothed particle hydrodynamics), PIC (particle-in-cell), etc., is becoming a practical tool for exploring lab-scale gas-solid systems owing to the fast development of parallel computation. However, gas-solid coupling and the corresponding fluid flow solver remain immature. In this work, we propose a modified lattice Boltzmann approach to consider the effect of both the local solid volume fraction and the local relative velocity between particles and fluid, which is different from the traditional volume-averaged Navier-Stokes equations. A time-driven hard sphere algorithm is combined to simulate the motion of individual particles, in which particles interact with each other via hard-sphere collisions, the collision detection and motion of particles are performed at constant time intervals. The EMMS (energy minimization multi-scale) drag is coupled with the lattice Boltzmann based discrete particle simulation to improve the accuracy. Two typical fluidization processes, namely, a single bubble injection at incipient fluidization and particle clustering in a fast fluidized bed riser, are simulated with this approach, with the results showing a good agreement with published correlations and experimental data. The capability of the approach to capture more detailed and intrinsic characteristics of particle-fluid systems is demonstrated. The method can also be used straightforward with other solid phase solvers.Graphical abstract: The governing equations of gas flow in DPS are described by a modified LBE with a reasonable consideration of the effect of both the local solid volume fraction and the local relative velocity between particles and fluid rather than the volume-averaged Navier-Stokes equations. A gas phase leaves the roof of bubble, and the downward moving particles near wall drag the gas to the bottom of the bubble where it re-enters the bubble region, which results in a pair of symmetrical vortices can be observed in the neighborhood of the rising bubble (Snapshots of the detailed flow field for gas phase).Display OmittedHighlights: • Lattice Boltzmann based discrete particle simulation is proposed and validated. • The EMMS drag has been coupled with lattice Boltzmann based DPS. • The modified LBE restores the effect of porosity and slip velocity on gas flows. • LES incorporated into the LBM to model turbulence in gas-solid fluidization. • The proposed method is able to simulate the size of particles below millimeter.
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