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排序方式: 共有3706条查询结果,搜索用时 15 毫秒
1.
Haitao Zhang Zonghai Chen Yongji Wang Ming Li Ting Qin 《International Journal of Adaptive Control and Signal Processing》2006,20(2):53-76
Laguerre Functional Model has many advantages such as good approximation capability for the variances of system time‐delay, order and other structural parameters, low computational complexity, and the facility of online parameter identification, etc., so this model is suitable for complex industrial process control. A series of successful applications have been gained in linear and non‐linear predictive control fields by the control algorithm based on Laguerre Functional Model, however, former researchers have not systemically brought forward the theoretical analyses of the stability, robustness, and steady‐state performance of this algorithm, which are the keys to guarantee the feasibility of the control algorithm fundamentally. Aimed at this problem, we introduce the principles of the Incremental Mode Linear Laguerre Predictive Control (IMLLPC) algorithm, and then systemically propose the theoretical analyses and proofs of the stability and robustness of the algorithm, in addition, we also put forward the steady‐state performance analysis. At last, the control performances of this algorithm on two different physical industrial plants are presented in detail, and a number of experimental results validate the feasibility and superiority of IMLLPC algorithm. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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预测控制算法的统一格式及其在电加热炉的应用 总被引:4,自引:0,他引:4
本文根据常用的两类预测控制算法推出一种新型预测控制算法。并将其应用于一双输入/双输出的力学持久机电加热炉的温度控制系统上,获得了满意的结果:控温精度为±1.5℃/300℃,且适用于非最小相位系统。 相似文献
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In a series of experiments, participants were required to keep track of 1 or 2 working memory (WM) objects, having to update their values in 80% of the trials. Updating cost, defined as the difference between update and non-update trials, was larger when 2 objects were involved compared with when there was only 1 object was involved. This finding was interpreted as evidence that the updating process encompasses both objects in WM, even though only 1 of them is actually updated. This feature of WM updating is limited to objects defined as "updateable," throughout the trial sequence. The results are explained by the need to reprogram the phonological loop when updating or the need for desynchronization followed by resynchronization of WM contents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Mou Weimin; Biocca Frank; Owen Charles B.; Tang Arthur; Xiao Fan; Lim Lynette 《Canadian Metallurgical Quarterly》2004,10(4):238
In 3 experiments, the authors investigated spatial updating in augmented reality environments. Participants learned locations of virtual objects on the physical floor. They were turned to appropriate facing directions while blindfolded before making pointing judgments (e.g., "Imagine you are facing X. Point to Y"). Experiments manipulated the angular difference between the learning heading and the imagined heading and between the actual heading and the imagined heading. The effect of actual-imagined on pointing latency was observed for naive users but not for users with brief training or instructions concerning the fact that objects can move with body movements. The results indicated that naive users used an environment-stabilized reference frame to access information arrays, but with experience and instruction the nature of the representation changed from an environment stabilized to a body stabilized reference frame. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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光纤陀螺可应用于旋转弹导航上,以提高其精确打击能力。基于光纤陀螺的捷联惯性导航系统是实现这一目的的重要手段之一。其中,姿态更新算法是捷联惯性导航系统的核心。针对旋转弹短时、近程的特点,提出一种基于修正型罗德里格斯参数的全姿态更新算法,并给出适合旋转弹姿态确定的数学模型。仿真结果表明与传统姿态更新算法相比较,新算法可以更有效的抑制不可交换误差,降低跟随时间的累积误差,减少高动态环境下的计算量,提高算法结算的速度和精度。 相似文献
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In Role Based Access Control (RBAC) systems, it is necessary and important to update the role–permission assignments in order to reflect the evolutions of the system transactions. However, role updating is generally complex and challenging, especially for large-scale RBAC systems. This is because the resulting state is usually expected to meet various requirements and constraints. In this paper, we focus on a fundamental problem of role updating in RBAC, which determines whether there exists a valid role–permission assignment, i.e., whether it can satisfy all the requirements of the role updating and without violating any role–capacity or permission–capacity constraint. We formally define such a problem as the Role Updating Feasibility Problem (RUFP), and study the computational complexity of RUFP in different subcases. Our results show that although several subcases are solvable in linear time, this problem is NP-complete in the general case. 相似文献
10.
The prototyping of complex sheet metal parts using single point incremental forming (SPIF) requires the generation of optimal tool paths and/or tool path sequences that ensure that the formed part is within geometric design specifications. The presence of a multitude of features on complex parts leads to multiple inaccuracy inducing phenomena occurring simultaneously due to interactions between the features. This paper proposes a network analysis methodology using topological conceptual graphs to capture the effects of different phenomena on the final accuracy of a sheet metal part manufactured by SPIF. Using this framework optimized tool paths can be generated that compensate for the inaccuracy inducing behavior. Tool path generation algorithms to create partial tool paths that account for the accuracy of specific features in the part based on the proposed framework are also presented. Finally, the creation of integrated tool paths maintaining complementarity between tool paths and desired continuity behavior using non-uniform cubic B-splines is illustrated. A number of case studies demonstrating the applicability of the integrated framework are discussed, where the maximum deviations in the part are significantly reduced and the average absolute deviations for the complete part are brought down to less than 0.5 mm. 相似文献