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911.
一种电液伺服系统中伺服控制器的设计与应用 总被引:1,自引:0,他引:1
文章设计了一种采用双DSP结构的伺服控制器,介绍了其组成结构、功能以及在电液伺服系统控制中的应用。将DSP芯片和数字信号处理技术结合,采用模糊算法设计以及同步协调设计,完成对原有单一通道、非同步的电液伺服系统扩充。多通道多变量大容量协调同步控制的复杂电液伺服系统具有强大的数据采集能力,64通道动态数据采集,320通道静态数据采集,完全满足大型结构试验的需要。 相似文献
912.
A motion-tolerant dissolve detection algorithm 总被引:1,自引:0,他引:1
Chih-Wen Su Liao H.-Y.M. Hsiao-Rong Tyan Kuo-Chin Fan Liang-Hua Chen 《Multimedia, IEEE Transactions on》2005,7(6):1106-1113
Gradual shot change detection is one of the most important research issues in the field of video indexing/retrieval. Among the numerous types of gradual transitions, the dissolve-type gradual transition is considered the most common one, but it is also the most difficult one to detect. In most of the existing dissolve detection algorithms, the false/miss detection problem caused by motion is very serious. In this paper, we present a novel dissolve-type transition detection algorithm that can correctly distinguish dissolves from disturbance caused by motion. We carefully model a dissolve based on its nature and then use the model to filter out possible confusion caused by the effect of motion. Experimental results show that the proposed algorithm is indeed powerful. 相似文献
913.
914.
Generalized Stewart-Gough platforms and their direct kinematics 总被引:5,自引:0,他引:5
In this paper, we introduce the generalized Stewart-Gough platform (GSP) consisting of two rigid bodies connected with six distance and/or angular constraints between six pairs of points, lines, and/or planes in the base and the moving platform, respectively. We prove that there exist 3850 possible forms of GSPs. We give the upper bounds for the number of solutions of the direct kinematics for all the GSPs. We also obtain closed-form solutions and the best upper bounds of real solutions of the direct kinematics for a class of 1120 GSPs. 相似文献
915.
916.
本文介绍了艾默生大功率TD3000变频器在抓斗行车的运用。抓斗行车变频改造后,很好地解决了主/闭钢丝绳受力平衡问题,软启软停方式大大降低了起制动时的冲击电流,再加上变频器本身具有完善灵敏保护功能,极大地提高了行车运行的可靠性,延长了系统的使用寿命。 相似文献
917.
职务犯罪成因的分析有助于职务犯罪的预防,近年来我国正处于社会转型时期,职务犯罪较为猖獗,本文从法律文化的角度出发,探讨了职务犯罪的概念覆其成因,以期在前人研究的基础上,进一步丰富职务犯罪成因探讨的成果,为我国职务犯罪控制提供法律文化学的对策。 相似文献
918.
Zhang Hong-hui Liao Chang-rong Chen Wei-min 《中国矿业大学学报(英文版)》2006,16(1):50-52,56
With the revival of magnetorheological technology research in the 1980's, its application in vehicles is increasingly focused on vibration suppression. Based on the importance of magnetorheological damper modeling, nonparametric modeling with neural network, which is a promising development in semi-active online control of vehicles with MR suspension, has been carried out in this study. A two layer neural network with 7 neurons in a hidden layer and 3 inputs and 1 output was established to simulate the behavior of MR damper at different excitation currents. In the neural network modeling, the damping force is a function of displacement, velocity and the applied current. A MR damper for vehicles is fabricated and tested by MTS; the data acquired are utilized for neural network training and validation. The application and validation show that the predicted forces of the neural network match well with the forces tested with a small variance, which demonstrates the effectiveness and precision of neural network modeling. 相似文献
919.
Synthesis, Structure and Characterization of Y-Al-Cr Red Pigment 相似文献
920.
Hongbin Zhang Chunguang Li Xiaofeng Liao 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2006,36(3):685-698
This paper presents a novel approach to stability analysis of a fuzzy large-scale system in which the system is composed of a number of Takagi-Sugeno (T-S) fuzzy subsystems with interconnections. The stability analysis is based on Lyapunov functions that are continuous and piecewise quadratic. It is shown that the stability of the fuzzy large-scale systems can be established if a piecewise Lyapunov function can be constructed, and, moreover, the function can be obtained by solving a set of linear matrix inequalities (LMIs) that are numerically feasible. It is also demonstrated via a numerical example that the stability result based on the piecewise quadratic Lyapunov functions is less conservative than that based on the common quadratic Lyapunov functions. The H/sub /spl infin// controllers can also be designed by solving a set of LMIs based on these powerful piecewise quadratic Lyapunov functions. 相似文献