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951.
952.
针对形如K/[(TS 1)S]的跟瞄伺服系统采用双 模控制算法实现该系统在大角度偏差情况下的快速调转,并且叙述了这种方法的数字实现。 相似文献
953.
对基于图像内容检索的图像特征值参数进行了分析和处理 ,在此基础上 ,探讨了建立特征值的一些因素 ,提出了一个基于因素的控制模型及算法思想 ,它能利用诸如知识库等进行反馈学习 ,从而达到提高检索效果的一种特征值提取方法 相似文献
954.
本文提出了一种步进电机闭环控制原理。根据这一原理 ,介绍了由单片机实现对步进电机自动升降速闭环控制的方法。 相似文献
955.
The paper addresses two of the basic issues of switching supervisory control (SSC): controller falsification (CF) and inference of candidate loop behaviour (ICLB). CF is approached as a statistical fault detection problem in that the currently operating controller is falsified as soon as a divergence trend is detected. This is achieved by considering a statistic (or residual) in the form of a ratio of closed-loop variables, and the falsification test is carried out by comparing at each time the ratio statistic with a threshold. It is constructively shown that the thresholds can be fixed, irrespective of the disturbance intensity, in such a way that faults are detected with probability one while probability of false alarms can be made as small as we wish. The ICLB issue is approached by the virtual reference approach. This allows one to obtain an inference of the performance of a candidate loop via a mean-square average of suitably filtered prediction errors. It is shown how a supervisory logic can be built by combining the results on CF with those on ICLB. 相似文献
956.
This paper describes the swing-up and stabilization of a cart–pendulum system with a restricted cart track length and restricted control force using generalized energy control methods. Starting from a pendant position, the pendulum is swung up to the upright unstable equilibrium configuration using energy control principles. An “energy well” is built within the cart track to prevent the cart from going outside the limited length. When sufficient energy is acquired by the pendulum, it goes into a “cruise” mode when the acquired energy is maintained. Finally, when the pendulum is close to the upright configuration, a stabilizing controller is activated around a linear zone about the upright configuration. The proposed scheme has worked well both in simulation and a practical setup and the conditions for stability have been derived using the multiple Lyapunov functions approach. 相似文献
957.
发电机励磁控制系统调节器的抗扰设计 总被引:1,自引:0,他引:1
在认真研究了发电机励磁系统数学模型后,明确了机械功率是励磁系统的 一个确定型(非随机的)扰动这一物理事实。指出过去在设计励磁调节器时, 所做的发电机调速器不动作这一假设是不妥当的。据此提出了发电机励磁调节 器的抗扰设计方案。即在通常的最优励磁调节器中引入一个伺服补偿器,该 伺服补偿器实质是引入了发电机端电压偏差的积分反馈。数字仿真表明该设计方 案有效地解决了过去设计的最优励磁调节器所存在的静态性能较差的问题,相 应所设计的抗扰励磁调节器能真正做到维持发电机端电压在给定值上运行,且 有良好的功角特性。 相似文献
958.
959.
J. M. Sloss I. S. Sadek J. C. Bruch Jr. S. Adali 《Canadian Metallurgical Quarterly》1992,5(1):127-137
The optimal layer thicknesses and optimal feedback control function are determined for a symmetric, cross‐ply laminate. The objectives of the optimization are to maximize the biaxial buckling load (design objective) and to minimize the dynamic response to external disturbances (control objective) subject to a constraint on the expenditure of control energy. The design∕control problem is formulated as a multiobjective optimization problem by employing a performance index that combines the design and control objectives in a weighted sum. Numerical results are given for a laminate made of an advanced composite material. Comparisons of controlled and uncontrolled laminates as well as optimally designed and nonoptimal laminates indicate the benefits of treating the design and control problems in unified formulation. The implications of solving these two problems are discussed. The values of optimal design and control variables are given for a number of problem parameters. 相似文献
960.
Rip G. Rice Ph.D. 《臭氧:科学与工程》2002,24(1):1-15
As we enter this new century, it is striking how the number of applications for ozone is growing. During ozone's first century, the emphasis for using it involved primarily, potable water treatment, wastewater treatment, bottled water treatment, odor control and medical therapy. Of these, potable water and wastewater treatment now can be called the “classical” applications for ozone. But there are a great many more uses for this versatile chemical that might be termed “non-classical”, and these began emerging toward the end of the last century. Some of these so-called “non-classical” developing applications for ozone will be reviewed in this paper. As we enter the 21s1 century, applications for ozone in the various aspects of the agricultural and food processing industries are very active and most promising. 相似文献