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991.
Batch process is a typical multi-phase process. Due to the interaction between the phases of the batch process, high precision control in a single phase cannot guarantee high precision control of the whole batch process. In order to solve this problem, the guaranteed cost iterative learning control (ILC) of multi-phase batch processes is studied in this paper. Firstly, through introducing the output error, the state error and the extended information, the multi-phase batch process is transformed into an equivalent 2D switched system which has different dimensions. In addition, under the measurable condition, the guaranteed cost iterative learning control law with extended information is designed. The proposed control law ensures not only the stability of the system but also the optimal control performance. Next, in order to study the stability of the system and the minimum running time under the condition of stable running, the multi-Lyapunov function method is used. By means of the average dwell time method, the sufficient conditions ensuring system to be exponentially stable are given in the form of linear matrix inequality (LMI). Finally, the injection molding process is taken as an example to make simulation, which shows the feasibility and effectiveness of the proposed method. 相似文献
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993.
在“互联网+”时代的到来,以及全民教育、终身学习的思想在全社会的推广,高职院校课堂教学重点应适应时代发展,向“激发学生内在学习动力,实现终身学习”的方向转变。根据教学经验,制定出针对不同层次学生的分层次教学方法,运用在日常教学活动中,最终通过该方法完成教学任务,实现教学目标。 相似文献
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997.
文章论述了沉管隧道管段临时支承系统的三点支承、四点支承、五点支承等几种主要形式,并进行了分析对比;同时介绍了五点式支承系统在越南西贡东西高速公路过江沉管隧道工程中的应用情况以及支承系统的设计与施工控制。研究结果及工程实践均表明:五点式支承系统在管段安装后始终能保证有三个支承点,可确保管段水下姿态稳定,同时具有更高的安装精度,尤其适合线路长、管段多的沉管隧道。 相似文献
998.
X. L. Cui H. G. Yang Q. Zhang H. Ouyang M. H. Zhu 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2016,54(3):353-369
In Chinese metro lines, rail corrugation on both tangential and tight curved tracks with Cologne-egg type fasteners is very severe. Based on the viewpoint of friction-induced vibration causing rail corrugation, the rail corrugation on a tangential track with Cologne-egg type fasteners is studied in this paper. A vibration model of an elastic multiple-wheelset-track system with Cologne-egg type fasteners is established. Both the complex eigenvalue analysis and the transient dynamic analysis are performed to study the stability and the dynamic performance of the wheelset-track system. The simulation results show that a low rail support stiffness value is responsible for rail corrugation on the tangential track. When the Cologne-egg fasteners characterised by a lower stiffness value are replaced with the DTVI2 fasteners characterised by a higher stiffness value, rail corrugation disappears. However, rail corrugation on tight curved tracks cannot be suppressed using the same replacement. The above conclusions are consistent with the corrugation occurrences in actual metro tracks. 相似文献
999.
针对具有需求扰动风险的供应链协调问题,基于利益驱动机制,设计出一种新的保险契约模式,建立相应的供应链模型并求解分析。结果表明:均匀分布市场需求下赔偿上限应足够大,且契约参数满足相关条件时供应链可以达到完美协调。最后通过数值分析了赔偿参数对订货量和保费的影响。 相似文献
1000.
Association analysis is an effective data mining approach capable of unveiling interesting associations within a large dataset.
Although widely adopted in e-business areas, it still has many difficulties when applied in practice. For instance, there
is a mismatch between the static rules discovered and the drifting nature of the user interests, and it is difficult to detect
associations from a huge volume of raw user data. This paper presents an effective approach to mine evolving association rules
in order to tackle these problems. It is followed by a recommendation model based on the evolving association rules unveiled.
Experimental results on an online toggery show that it can effectively unveil people’s shifting interests and make better
recommendations accordingly. 相似文献