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基于特征融合的人体行为识别 总被引:5,自引:5,他引:0
为克服单个行为表达方法有效性上的不足,提出了一种基于多特征融合和支持向量机(SVM)的人体行为识别(HAR)方法。首先,利用背景差分提取运动显著区域;然后提取运动显著区域的剪影直方图和光流直方图,并采取一定的融合策略,构建融合特征结合SVM识别人体行为。实验以广泛使用的公开数据集Weizmann为研究对象,正确识别率达到99.8%以上。结果表明,提出的特征融合及识别方法能有效地对人体行为进行识别;而且,由于规避了比较耗时的序列匹配操作,减少了计算量。 相似文献
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《Journal of Visual Communication and Image Representation》2014,25(1):24-38
Much of the existing work on action recognition combines simple features with complex classifiers or models to represent an action. Parameters of such models usually do not have any physical meaning nor do they provide any qualitative insight relating the action to the actual motion of the body or its parts. In this paper, we propose a new representation of human actions called sequence of the most informative joints (SMIJ), which is extremely easy to interpret. At each time instant, we automatically select a few skeletal joints that are deemed to be the most informative for performing the current action based on highly interpretable measures such as the mean or variance of joint angle trajectories. We then represent the action as a sequence of these most informative joints. Experiments on multiple databases show that the SMIJ representation is discriminative for human action recognition and performs better than several state-of-the-art algorithms. 相似文献
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《Journal of Visual Communication and Image Representation》2014,25(2):329-338
Due to the exponential growth of the video data stored and uploaded in the Internet websites especially YouTube, an effective analysis of video actions has become very necessary. In this paper, we tackle the challenging problem of human action recognition in realistic video sequences. The proposed system combines the efficiency of the Bag-of-visual-Words strategy and the power of graphs for structural representation of features. It is built upon the commonly used Space–Time Interest Points (STIP) local features followed by a graph-based video representation which models the spatio-temporal relations among these features. The experiments are realized on two challenging datasets: Hollywood2 and UCF YouTube Action. The experimental results show the effectiveness of the proposed method. 相似文献
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稀散金属铟独立矿床很少,常伴生锌硫化矿中,湿法或火法炼锌时铟富集到多种渣中,铟铁酸锌等难浸物存在使铟回收工艺复杂且回收率低。本文重点介绍几种锌固废提铟浸出工艺,常规酸浸原料适用范围少且回收率低,而针对难浸矿物则需采用加压富氧酸浸、热酸浸出、焙烧预处理、氯盐浸出等工艺。锌渣焙烧预处理后难溶硫化铟转化为硫酸铟,难溶硅酸盐结构也可被破坏,铟的浸出率达93%以上。采用复合场强化铟浸出具有很大应用潜力。传统萃取法工艺较复杂、后期操作也不好控制、离子分离困难,采用新型浸出后续处理工艺,包括石灰石中和水解沉淀,水解沉铟、离子交换树脂、生物浸出、真空蒸馏法,实现铟进一步富集。因此,未来辅助使用复合外场或联合多种方法从内部破坏难溶物结构实现铟铁分离和铟铁酸锌的溶解,锌固废提铟工艺革新,研发新型萃取剂均可成为未来发展方向。 相似文献
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Paulina Kosikowska-Adamus Emilia Sikorska Dariusz Wyrzykowski Aleksandra Walewska Anna Golda Milena Deptua Micha Obuchowski Adam Prahl Micha Pikua Adam Lesner 《International journal of molecular sciences》2021,22(13)
The alarming raise of multi-drug resistance among human microbial pathogens makes the development of novel therapeutics a priority task. In contrast to conventional antibiotics, antimicrobial peptides (AMPs), besides evoking a broad spectrum of activity against microorganisms, could offer additional benefits, such as the ability to neutralize toxins, modulate inflammatory response, eradicate bacterial and fungal biofilms or prevent their development. The latter properties are of special interest, as most antibiotics available on the market have limited ability to diffuse through rigid structures of biofilms. Lipidation of AMPs is considered as an effective approach for enhancement of their antimicrobial potential and in vivo stability; however, it could also have undesired impact on selectivity, solubility or the aggregation state of the modified peptides. In the present work, we describe the results of structural modifications of compounds designed based on cationic antimicrobial peptides DK5 and CAR-PEG-DK5, derivatized at their N-terminal part with fatty acids with different lengths of carbon chain. The proposed modifications substantially improved antimicrobial properties of the final compounds and their effectiveness in inhibition of biofilm development as well as eradication of pre-formed 24 h old biofilms of Candida albicans and Staphylococcus aureus. The most active compounds (C5-DK5, C12-DK5 and C12-CAR-PEG-DK5) were also potent against multi-drug resistant Staphylococcus aureus USA300 strain and clinical isolates of Pseudomonas aeruginosa. Both experimental and in silico methods revealed strong correlation between the length of fatty acid attached to the peptides and their final membranolytic properties, tendency to self-assemble and cytotoxicity. 相似文献