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C2S转晶反应定量调控 总被引:2,自引:0,他引:2
综合报道了C2S转晶反应定量调控的研究结果。宏观工艺研究表明:γ-C2S适宜烧成温度为1250-1500℃,冷却方式与速率对转晶反应影响不显著;微观研究表明:调节β-C2S稳定剂浓度可定量调控C2S转晶反应,稳定剂稳定效果与烧成温度有关,且受其它杂质离子干扰,Al2O3,Fe2O3组晶反应有双向调控效应。 相似文献
83.
扩散控制下固定床电化学反应器研究:(Ⅲ)反应器的设计与操作 总被引:1,自引:1,他引:1
采用一维反应器模型对扩散控制下固定床电化学反应器的设计进行了详细的讨论,并对反应器的优化操作进行了初步探讨。 相似文献
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Choosing an appropriate control scheme to alleviate nonlinearities and uncertainties is not a trivial task, especially when models are not easily available and practical evaluation provides the only means for actual performance assessment. Various factors can contribute to these nonlinearities and uncertainties, such as friction and stiction. Thus, this article investigates four different control schemes, namely PID, adaptive, conventional sliding mode control (SMC) and integral sliding mode control (ISMC) which are implemented in the Bristol Elumotion Robot Hand (BERUL) to analyse and overcome the aforementioned problems. The hand has five fingers with 16 joints and all fingers are underactuated. The implementation of the proposed control schemes are challenging since the BERUL fingers have significant friction, stiction and unknown parameters. The fingers are light in weight and fragile. Comparative performance characteristics have shown that the ISMC is the most suitable candidate to provide good experimental trajectory following and positioning control for underactuated BERUL fingers. 相似文献
86.
Considering gravity change from ground alignment to space applications, a fuzzy proportional-integral-differential (PID) control strategy is proposed to make the space manipulator track the desired trajectories in different gravity environments. The fuzzy PID controller is developed by combining the fuzzy approach with the PID control method, and the parameters of the PID controller can be adjusted on line based on the ability of the fuzzy controller. Simulations using the dynamic model of the space manipulator have shown the effectiveness of the algorithm in the trajectory tracking problem. Compared with the results of conventional PID control, the control performance of the fuzzy PID is more effective for manipulator trajectory control. 相似文献
87.
Trajectory tracking and roll stabilization are both vital practices in ship motion control. Trajectory tracking is a kind of low‐frequency control, while roll stabilization by means of fins is a kind of high‐frequency control. However, they have been studied separately previously; most tracking control of underactuated surface vessels in the previous studies do not account for roll stabilization by means of fins. In reality, however, they are an integral system. In this paper, a simple control strategy is proposed to achieve trajectory tracking and fin roll stabilization simultaneously. Four degrees of freedom derived from a six degrees of freedom mathematical model of a surface vessel is considered, including surge, sway, roll and yaw. Surge force, roll moment and yaw moment are considered as control inputs, while position, yaw angle and roll angle are controlled. The number of control inputs is fewer than the outputs to be controlled. Therefore, we are dealing with an underactuated problem. An adaptive hierarchical sliding mode control technique is employed to deal with the underactuation. Stabilization of underactuated surface vessels is studied as a special case. Random waves are applied to test the robustness of the designed controllers. Lyapunov stability theory is used to show the stability of closed‐loop system. The simulation results verify the effectiveness of the proposed strategy. 相似文献
88.
针对移动机器人路径规划问题,提出一种基于QPSO算法的路径规划方法,并用概率论的方法分析了移动机器人路径规划的收敛性,阐明了该方法随均匀分布和正态分布的参数关系和收敛区间;然后根据移动机器人的运动特征提出一种改进的轨迹规划方法。移动机器人平台的实验结果表明了该方法在移动机器人路径规划中的有效性和可行性。 相似文献
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