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71.
Tong  Ming  Yan  Kaibo  Jin  Lei  Yue  Xing  Li  Mingyang 《Neural computing & applications》2021,33(15):9375-9389
Neural Computing and Applications - Video-based human action recognition remains a challenging task. There are three main limitations: (1) Most works are only restricted to single temporal scale...  相似文献   
72.
Graphs appear in numerous applications including cyber security, the Internet, social networks, protein networks, recommendation systems, citation networks, and many more. Graphs with millions or even billions of nodes and edges are common-place. How to store such large graphs efficiently? What are the core operations/queries on those graph? How to answer the graph queries quickly? We propose Gbase, an efficient analysis platform for large graphs. The key novelties lie in (1) our storage and compression scheme for a parallel, distributed settings and (2) the carefully chosen graph operations and their efficient implementations. We designed and implemented an instance of Gbase using Mapreduce/Hadoop. Gbase provides a parallel indexing mechanism for graph operations that both saves storage space, as well as accelerates query responses. We run numerous experiments on real and synthetic graphs, spanning billions of nodes and edges, and we show that our proposed Gbase is indeed fast, scalable, and nimble, with significant savings in space and time.  相似文献   
73.
A water drop behaves differently from a large water body because of its strong viscosity and surface tension under the small scale. Surface tension causes the motion of a water drop to be largely determined by its boundary surface. Meanwhile, viscosity makes the interior of a water drop less relevant to its motion, as the smooth velocity field can be well approximated by an interpolation of the velocity on the boundary. Consequently, we propose a fast deformable surface model to realistically animate water drops and their flowing behaviors on solid surfaces. Our system efficiently simulates water drop motions in a Lagrangian fashion, by reducing 3D fluid dynamics over the whole liquid volume to a deformable surface model. In each time step, the model uses an implicit mean curvature flow operator to produce surface tension effects, a contact angle operator to change droplet shapes on solid surfaces, and a set of mesh connectivity updates to handle topological changes and improve mesh quality over time. Our numerical experiments demonstrate a variety of physically plausible water drop phenomena at a real-time rate, including capillary waves when water drops collide, pinch-off of water jets, and droplets flowing over solid materials. The whole system performs orders-of-magnitude faster than existing simulation approaches that generate comparable water drop effects.  相似文献   
74.
绩效管理是人力资源管理的核心,对企业实现战略目标有举足轻重的作用,绩效测评是绩效管理中必不可少的组成部分。本文讲述了一种全面客观的360度绩效测评法,并介绍了一套按照360度绩效测评模型构建的B/S办公系统,重点介绍了使用这套系统进行绩效测评的过程,以便通过信息化手段,有效的运用这一先进测评方法,为企业管理提供有益的支持。  相似文献   
75.
Experimental investigations have been made in which single crystals of solid explosives such as cyclotrimethylene trinitramine, RDX, pentaerythritol tetranitrate, PETN, AgN3 and Pb(N3)2, were irradiated with a focused laser beam of wavelength 266 nm and duration 5 nsec in an ultra high vacuum system housing a fast and sensitive time-of-flight mass spectrometer. From the mass spectra (both +ve and -ve ions) of the chemical species obtained, possible decomposition schemes of RDX and PETN have been proposed. For silver and lead azides, the laser irradiation did not cause explosions if the power density was sufficiently low, but micrometre size craters were formed. In the mass spectra of AgN3 products N3 and silver cluster ions, Ag n +, have been found for the first time. It has been suggested that such investigations may possibly throw some light on our understanding of the reactions taking place in a deflagration/detonation wave.  相似文献   
76.
砷、氟污染水体及其共存问题是环境领域的热点问题,长期暴露其中对公众的身体健康存在巨大威胁.文章梳理了砷、氟污染物的来源,及砷、氟污染水体的分布与危害,并按吸附、离子交换、反渗透、电絮凝、膜法等分析了用于砷、氟处理的各类技术手段的利弊,以期为后续水体中砷、氟污染物的高效去除提供参考.  相似文献   
77.
Electrochemical Study on Formation of Dy-Ni Alloy in Molten Chlorides   总被引:1,自引:1,他引:1  
ElectrochemicalStudyonFormationofDy-NiAlloyinMoltenChloridesTongYexiang;LiuGuankun;YangQiqin;HongHuichan,(童叶翔)(刘冠昆)(杨绮琴)(洪惠婵)...  相似文献   
78.
薄膜应力的测量一直是一个困难的问题。本文尝试用一种新的方法——X射线衍射-拉伸法,对薄膜的应力进行检测,与侧倾法实验结果相比较,X射线衍射-拉伸法更为准确与可靠。  相似文献   
79.
针对发电机励磁系统运行时的动静态性能要求,分析了内燃动车柴油发电机的控制特点,提出一种模糊滑模复合控制策略.利用滑模控制对扰动与参数不敏感的特性,可有效解决发电机励磁控制的鲁棒性问题;同时采用模糊控制,根据输出变化量和变化率在同步发电机运行过程中实现实时调整滑膜控制器的参数.仿真结果表明,与单纯的滑模控制相比,模糊滑膜控制器使发电机的端电压更稳定,具有较好的静态和动态性能.  相似文献   
80.
Introduction of C4 photosynthetic traits into C3 crops is an important strategy for improving photosynthetic capacity and productivity. Here, we report the research results of a variant line of sorghum–rice (SR) plant with big panicle and high spikelet density by introducing sorghum genome DNA into rice by spike-stalk injection. The whole-genome resequencing showed that a few sorghum genes could be integrated into the rice genome. Gene expression was confirmed for two C4 photosynthetic enzymes containing pyruvate, orthophosphate dikinase and phosphoenolpyruvate carboxykinase. Exogenous sorghum DNA integration induced a series of key traits associated with the C4 pathway called “proto-Kranz” anatomy, including leaf thickness, bundle sheath number and size, and chloroplast size in bundle sheath cells. Significantly, transgenic plants exhibited enhanced photosynthetic capacity resulting from both photosynthetic CO2-concentrating effect and improved energy balance, which led to an increase in carbohydrate levels and productivity. Furthermore, such rice plant exhibited delayed leaf senescence. In summary, this study provides a proof for the feasibility of inducing the transition from C3 leaf anatomy to proto-Kranz by spike-stalk injection to achieve efficient photosynthesis and increase productivity.  相似文献   
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