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991.
由于盘式电机的结构不同于常规电机,使它们的磁密转换系数、铁重以及铁耗的计算也不同.本文S根据盘式感应电动机的结构特点,提出铁耗计算的较优方法,和试验值相吻合. 相似文献
993.
侯浩波 《武汉大学学报(工学版)》1997,(5)
用不同固化剂对粉煤灰进行了室内和现场固化试验,并对固化粉煤灰的工程特性进行了分析,为固化粉煤灰作为灰坝筑坝材料提供了可靠依据. 相似文献
994.
分析了卫星测试无线转发中一点对多点通讯系统中的关键性技术:包括硬件连接、通讯方式及有关技术,并给出了具体方案。 相似文献
995.
Local stress peaks are the main reason for fatigue failure of structures, and therefore many researchers make every effort to search for effective methods of structural shape optimization. Mattheck and Burkhard (1990) have developed a method by simulating the self-optimization mechanism of biological growth, using FEM. BEM is a very effective method in which only the boundary is divided into elements, and particularly, accurate results at the boundary can be obtained. It is obvious that BEM is a more suitable analysis method for structural shape optimization than FEM. Coupling BEM of three-dimensional thermoelasticity problems with an optimization method based on biological growth, a novel method of structural shape optimization is successfully developed by the authors. Several examples are used to demonstrate that the method is successful and efficient. 相似文献
996.
In this paper, a new algorithm for convex quadratic programming (QP) is presented. Firstly, the surrogate problem for QP is developed, and the Karush-Kuhn-Tucker conditions of the surrogate problem hold if the unconstrained minimum of the objective function does not satisfy any constraints. Then, Karmarkar's algorithm for linear programming (LP) is introduced to solve the surrogate dual problem. In addition, the case of general constraints is also discussed, and some examples of optimum truss sizing problems show that the proposed algorithm is robust and efficient. 相似文献
997.
An adaptive learning algorithm is proposed for a feedforward neural network. The design principle is based on the sliding mode concept. Unlike the existing algorithms, the adaptive learning algorithm developed does not require a prioriknowledge of upper bounds of bounded signals. The convergence of the algorithm is established and conditions given. Simulations are presented to show the effectiveness of the algorithm. 相似文献
998.
Stability analysis for neural dynamics with time-varying delays 总被引:8,自引:0,他引:8
Hou Chunhai Qian Jixin 《Neural Networks, IEEE Transactions on》1998,9(1):221-223
By using the usual additive neural-network model, a delay-independent stability criterion for neural dynamics with perturbations of time-varying delays is derived. We extend previously known results obtained by Gopalsamy and He (1994) to the time varying delay case, and present decay estimates of solutions of neural networks. The asymptotic stability is global in the state space of neuronal activations. From the techniques used in this paper, it is shown that our criterion ensures stability of neural dynamics even when the delay functions vary violently with time. Our approach provides an effective method for the stability analysis of neural dynamics with delays. 相似文献
999.
Xie X. Sudhakar R. Zhuang H. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》1998,28(4):487-490
The authors previously (1995) proposed an efficient method for tracking the eye movements. The proposed algorithm did not address the issue of compensating for head movements. Head movements are normally much slower than eye movements and can be compensated for using another tracking scheme for head position. In this paper, a hybrid method employing the two tracking schemes is developed. To this end, first a measurement model for the compensation of the head movement is formulated and then the overall tracking scheme is implemented by cascading two Kalman filters. The tracking of the iris movement is followed by the compensation of the head movement for each image frame. Experimental results are presented to demonstrate the accuracy aspects and the real-time applicability of the proposed approach 相似文献
1000.