33 research outputs found

    Unified and Dynamic Graph for Temporal Character Grouping in Long Videos

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    Video temporal character grouping locates appearing moments of major characters within a video according to their identities. To this end, recent works have evolved from unsupervised clustering to graph-based supervised clustering. However, graph methods are built upon the premise of fixed affinity graphs, bringing many inexact connections. Besides, they extract multi-modal features with kinds of models, which are unfriendly to deployment. In this paper, we present a unified and dynamic graph (UniDG) framework for temporal character grouping. This is accomplished firstly by a unified representation network that learns representations of multiple modalities within the same space and still preserves the modality's uniqueness simultaneously. Secondly, we present a dynamic graph clustering where the neighbors of different quantities are dynamically constructed for each node via a cyclic matching strategy, leading to a more reliable affinity graph. Thirdly, a progressive association method is introduced to exploit spatial and temporal contexts among different modalities, allowing multi-modal clustering results to be well fused. As current datasets only provide pre-extracted features, we evaluate our UniDG method on a collected dataset named MTCG, which contains each character's appearing clips of face and body and speaking voice tracks. We also evaluate our key components on existing clustering and retrieval datasets to verify the generalization ability. Experimental results manifest that our method can achieve promising results and outperform several state-of-the-art approaches

    A Chinese Herbal Preparation Containing Radix Salviae Miltiorrhizae, Radix Notoginseng and Borneolum Syntheticum Reduces Circulating Adhesion Molecules

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    Circulating adhesion molecules (CAMs), surface proteins expressed in the vascular endothelium, have emerged as risk factors for cardiovascular disease (CVD). CAMs are involved in intercellular communication that are believed to play a role in atherosclerosis. A Chinese medicine, the “Dantonic Pill” (DP) (also known as the “Cardiotonic Pill”), containing three Chinese herbal material medica, Radix Salviae Miltiorrhizae, Radix Notoginseng and Borneolum Syntheticum, has been used in China for the prevention and management of CVD. Previous laboratory and animal studies have suggested that this preparation reduces both atherogenesis and adhesion molecule expression. A parallel double blind randomized placebo-controlled study was conducted to assess the effects of the DP on three species of CAM (intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 and endothelial cell selectin (E-selectin)) in participants with mild-moderate hypercholesterolemia. Secondary endpoints included biochemical and hematological variables and clinical effects. Forty participants were randomized to either treatment or control for 12 weeks. Treatment with DP was associated with a statistically significant decrease in ICAM-1 (9% decrease, P = .03) and E-Selectin (15% decrease, P = .004). There was no significant change in renal function tests, liver function tests, glucose, lipids or C-reactive protein levels and clinical adverse effects did not differ between the active and the control groups. There were no relevant changes in participants receiving placebo. These results suggest that this herbal medicine may contribute to the development of a novel approach to cardiovascular risk reduction

    Rapid Analysis of Illegal Cationic Dyes in Foods and Surface Waters Using High Temperature Direct Analysis in Real Time High-Resolution Mass Spectrometry

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    A high temperature desorption (HTD) direct analysis in real time-high-resolution mass spectrometric (DART-HRMS) method was developed for the rapid analysis of four banned cationic dyes. Rhodamine B is used to dye foods, while malachite green, crystal violet, and methylene blue are added to fishponds as antimicrobials. A simple induced phase separation extraction was used to pretreat samples. The DART-HRMS method employed two temperature steps, i.e., 200 °C for drying, purification, and enrichment of sample solution and 500 °C for thermal desorption and ionization of analytes. The calibration curves of dyes in the range of 50-2000 ng/mL were linear using deuterated malachite green as an internal standard. The LODs vary for all analytes between 0.1 and 30 ppb depending on the matrix and experimental conditions. Through analyses of real samples, two chili powders and one chili oil were found to be contaminated by rhodamine B. The concentrations were comparable with those found by an HPLC-MS/MS method.</p

    Temporary strong-motion observation network for Wenchuan aftershocks and site classification

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    AbstractThe Ms=8.0 (MW=7.9) Wenchuan earthquake of May 12, 2008 was the largest destructive event on the Chinese mainland since the 1976 Tangshan earthquake. Thousands of aftershocks occurred in the following months. To improve the performance of the National Strong-Motion Observation Network System (NSMONS) in China, a temporary strong-motion observation network was quickly set up along the Longmenshan Fault in the most heavily damaged areas. We briefly reviewed the history and the advances in temporary strong-motion observation in China where temporary networks have been proven to be a very effective way of accumulating strong-motion records from large aftershocks. Then the case of the Wenchuan earthquake was described together with the process of compiling, standardizing and disseminating the collected data. A total of 3250 records were collected from 92 temporary stations for 949 aftershocks between May 13 and October 10, 2008. The largest peak ground acceleration (PGA) is 966.5cm/s2 from an MS=4.2 earthquake on August 10, 2008. Some general statistics, such as the number of recorded events with various magnitudes, PGA and epicentral distance, were analyzed and compared with the data from permanent stations. These results show that the temporary network can effectively compensate for the large instrument spacing of the permanent network to record near-field ground motion. Since no borehole data are available for those temporary stations, their site classifications are inferred using a horizontal-to-vertical spectral ratio (HVSR) technique based on the observed strong-motion records. A scheme of six site classes is proposed to improve the reliability of the HVSR technique. As a result, the site classes of 66 temporary stations are recommended finally

    Regional terrain-based V S30 prediction models for China

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    Abstract Time-averaged shear-wave velocity to 30 m (V S30) is commonly used in ground motion models as a parameter for evaluating site effects. This study used a collection of boreholes in Beijing, Tianjin, Guangxi, Guangdong, and three other municipalities and provinces, which were divided into three regions with reference to the seismic ground motion parameter zonation map of China, to establish V S30 prediction models based on terrain categories. Regional effects were verified by comparing morphometric parameter (topographic slope, surface texture, and local convexity) thresholds and terrain classification maps obtained from global digital elevation model (DEM) data and regional DEM data of the three regions. Additionally, V S30 prediction models for the three regions using both types of terrain classification maps were established and analyzed comparatively to provide credible regional V S30 models for China. Through analysis of the correlations between the measured V S30 values and the predicted V S30 values, calculation of the mean squared error and mean absolute percentage error in each region, and with consideration of the geological characteristics of the boreholes, the V S30 prediction models based on terrain classification maps from regional data were finally applied in developing regional V S30 models for China. Intercomparison of the V S30 prediction models for the three regions indicated that subregional consideration is necessary in terrain classification. Finally, a spatial analysis method adopting inverse distance weighting of the residuals was used to update the initial V S30 models. The developed V S30 models could be used both in developing regional ground motion models and in the construction of earthquake disaster scenarios. Graphical Abstrac
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