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151.
Bai Qingchun Wei Kai Zhou Jie Xiong Chao Wu Yuanbin Lin Xin He Liang 《The Journal of supercomputing》2021,77(9):9474-9493
The Journal of Supercomputing - Sentiment analysis in Danmaku video interaction aims at measuring public mood in respect of the video, which is helpful for the potential applications in behavioral... 相似文献
152.
Yang Chao Ding Yijie Meng Qiaozhen Tang Jijun Guo Fei 《Neural computing & applications》2021,33(17):11387-11399
Neural Computing and Applications - RNA-binding proteins play an important role in the biological process. However, the traditional experiment technology to predict RNA-binding residues is... 相似文献
153.
随着无人机在军事和民用领域的应用前景,高效率的地面控制操控训练替代实装飞行是保证系统安全、提高效率和节省经费的重要手段,针对无人机飞行控制系统仿真的特点和人在回路仿真系统的要求,提出利用Matlab/Simulink提供仿真环境进行人在回路的无人机仿真系统的设计方案,该方案将PC机作为实时飞控系统,从而将其作为飞行控制的仿真平台,相对于传统手工编写代码的方式,基于Simulink模块构建的仿真模型具有灵活、快速、高效和低成本等特点,对无人机模拟训练系统中飞行动态仿真模型的设计和人在同路的仿真训练具有很高的实用价值. 相似文献
154.
针对目前对高度表进行原位检测的需求,设计了一种新的高度模拟方法;该方法的实现以ARM为核心,通过高度模拟电路产生各种需要的高度电压信号,从而达到高度模拟的目的,并且无需对机载高度表进行拆装,操作简单、快捷、可靠性较高;实验结果表明,这种方法的高度模拟精度较高,具有一定的实用价值和经济效益. 相似文献
155.
该文通过分析影响医疗信息化建设与快速发展的主要因素以及对于云计算技术的概念、特点及其发展现状进行了解,简要介绍了云计算技术为医疗卫生信息化建设提供的服务,分析了云计算技术为医疗信息化建设所带来的益处,探讨了云计算技术在医疗信息化应用中所面临的挑战。 相似文献
156.
Chao MW Lin CH Assa J Lee TY 《IEEE transactions on visualization and computer graphics》2012,18(5):729-740
The rapid growth of motion capture data increases the importance of motion retrieval. The majority of the existing motion retrieval approaches are based on a labor-intensive step in which the user browses and selects a desired query motion clip from the large motion clip database. In this work, a novel sketching interface for defining the query is presented. This simple approach allows users to define the required motion by sketching several motion strokes over a drawn character, which requires less effort and extends the users’ expressiveness. To support the real-time interface, a specialized encoding of the motions and the hand-drawn query is required. Here, we introduce a novel hierarchical encoding scheme based on a set of orthonormal spherical harmonic (SH) basis functions, which provides a compact representation, and avoids the CPU/processing intensive stage of temporal alignment used by previous solutions. Experimental results show that the proposed approach can well retrieve the motions, and is capable of retrieve logically and numerically similar motions, which is superior to previous approaches. The user study shows that the proposed system can be a useful tool to input motion query if the users are familiar with it. Finally, an application of generating a 3D animation from a hand-drawn comics strip is demonstrated. 相似文献
157.
P2P based live streaming has been gaining popularity. The new generation P2P live streaming systems not only attract a large number of viewers, but also support better video quality by streaming the content at higher bit-rate. In this paper, we propose a novel P2P streaming framework, called Hierarchically Clustered P2P Video Streaming, or HCPS, that can support the streaming rate approaching the optimal upper bound while accommodating large viewer population. The scalability comes with the hierarchical overlay architecture by grouping peers into clusters and forming a hierarchy among them. Peers are assigned to appropriate cluster so as to balance the bandwidth resources across clusters and maximize the supportable streaming rate. Furthermore, individual peers perform distributed queue-based scheduling algorithms to determine how to retrieve data chunks from source and neighboring peers, and how to utilize its uplink bandwidth to serve data chunks to other peers. We show that queue-based scheduling algorithms allow to fully utilize peers’ uplink bandwidths, and HCPS supports the streaming rate close to the optimum in practical network environment. The prototype of HCPS is implemented and various design issues/tradeoffs are investigated. Experiments over the PlanetLab further demonstrate the effectiveness of HCPS design. 相似文献
158.
S. O. Hyatt B. S. Chao H. Yamauchi 《Journal of Materials Science: Materials in Electronics》1992,3(1):41-47
TiN films were deposited on (100)-Si substrates by RF-reactive sputtering. The effects of processing parameters and substrate orientation on the stoichiometry, resistivity and microstructure of reactively sputtered TiN thin films were investigated. The RF-power was fixed at 50 W, and the nitrogen content in the working gas was adjusted so that target nitridation occurred at a relatively low nitrogen content, 2.6% N2, in a fixed total flow rate of gases of 46.25 standard cubic centimetres (sccm). The N2 percentage was varied from 2.6% to 15.4%. The films were continuous and 200 nm thick. Films deposited with the substrate facing the target exhibited 111-texturing, while films on substrates lying in the same plane of the target surface had 100-texturing. Both X-rays photoelectron spectroscopy and high-resolution detailed scans of the Auger electron energy spectrum were used for the stoichiometry determination. On the 100-textured TiN films, the N/Ti ratio was 1.0 at low N2 flow rates; the N/Ti ratio rapidly increased with N2 flow rate, and then levelled off. The films had resistivities ranging from 85 to 1340 µ cm, and the functional dependence of both N/Ti and the resistivity values behaved similarly with increasing N2. X-ray single-line profile analysis of the 200-reflection indicated that the average crystallite size decreased and the average strain increased with increasing nitrogen content in the working gas. The Si/TiN structures were heat treated in the temperature range from 300 to 600°C in a quartz tube under 1 atm (105Pa) of flowing high purity Ar gas. Heat treatment at 300°C did not affect the TiN film integrity, while treatment at 400–600°C resulted in void-type defects. 相似文献
159.
提取自然图像中的物体轮廓是机器视觉研究的重要问题,主要困难在于自然图像中的纹理性边缘严重干扰了物体轮廓的提取。研究表明视皮层方位选择性神经元的非经典感受野机制使得人类视觉系统在处理自然图像时不仅能够抑制纹理性边缘,而且能够增强物体的轮廓。基于此人们提出多种仿生轮廓检测算法,但算法中被称为抑制水平的参量在取值较高时会漏检部分轮廓,而在其取值较低时又会引入过多的纹理性边缘。针对这一问题,提出多水平外区抑制轮廓检测算法,通过整合各级单水平外区抑制的检测信息,有效抑制了纹理性边缘和降低了漏检轮廓的可能性。实验结果表明,相对于传统算法,新算法在轮廓检测性能上提高了10%左右,并具有更好的稳健性。 相似文献
160.
将磁流变技术应用于火炮反后坐装置是目前正在发展的一种降低火炮后坐力的新技术,优化火炮反后坐装置控制,达到实时调节阻力。针对某型号火炮,在建立动力学模型和电磁模型的基础上设计了磁流变反后坐系统。为实现理想的后坐控制规律,提出了PID和模糊控制算法。利用ADAMS和MATLAB进行联合仿真,仿真结果表明,在后坐行程范围内,最大后坐阻力分别为3.71×105N,3.53×105N,相比传统火炮减小了13%和17%,并且模糊控制的后坐阻力曲线具有良好的"平台效应",实现了控制目标,表明磁流变阻尼器良好的可控性和应用于火炮后坐系统中的可行性。 相似文献