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131.
This article addresses the output feedback control for discrete‐time Markov jump linear systems. With fully known transition probability, sufficient conditions for an internal model based controller design are obtained. For the case where the transition probabilities are uncertain and belong to a convex polytope with known vertices, we provide a sufficient LMI condition that guarantees the norm of the closed‐loop system is below a prescribed level. That condition can be improved through an iterative procedure. Additionally, we are able to deal with the case of cluster availability of the Markov mode, provided that some system matrices do not vary within a given cluster, an assumption that is suitable to deal with packet dropout models for networked control systems. A numerical example shows the applicability of the design and compares it with previous results. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
132.
Esteban J. Palomo Enrique Domínguez Rafael M. Luque-Baena José Muñoz 《Neural Processing Letters》2013,37(1):69-87
Both image compression based on color quantization and image segmentation are two typical tasks in the field of image processing. Several techniques based on splitting algorithms or cluster analyses have been proposed in the literature. Self-organizing maps have been also applied to these problems, although with some limitations due to the fixed network architecture and the lack of representation in hierarchical relations among data. In this paper, both problems are addressed using growing hierarchical self-organizing models. An advantage of these models is due to the hierarchical architecture, which is more flexible in the adaptation process to input data, reflecting inherent hierarchical relations among data. Comparative results are provided for image compression and image segmentation. Experimental results show that the proposed approach is promising for image processing, and the powerful of the hierarchical information provided by the proposed model. 相似文献
133.
Upflow anaerobic sludge bed reactors fed on glucose were used to investigate the effects of Ce(3+) on soluble microbial products (SMP) production, which is the majority of the residual chemical oxygen demand present in the effluent. It was found that Ce(3+) concentration of 0.05 mg/L had no significant effect on the amount of SMP production, whereas that of 1 mg/L led to the increase in SMP production. The molecular-weight distribution and carbohydrate analysis indicated that an increase in SMP production may be partly attributed to the release of extracellular polymeric substances (EPS) into the bulk solution resulted from cerium toxicity, and the nucleic acids analysis suggested that increased cell lysis also contributed to SMP accumulation in the presence of Ce(3+). The increase in SMP production in the presence of Ce(3+) is possibly a consequence of the release of EPS and increased cell lysis due to cerium toxicity. 相似文献
134.
135.
Basil Mohammed Al-Hadithi Antonio Javier Barragán José Manuel Andújar Agustín Jiménez 《Applied Soft Computing》2013,13(12):4802-4812
In this paper, a fuzzy based Variable Structure Control (VSC) with guaranteed stability is presented. The main objective is to obtain an improved performance of highly non-linear unstable systems. The main contribution of this work is that, firstly, new functions for chattering reduction and error convergence without sacrificing invariant properties are proposed, which is considered the main drawback of the VSC control. Secondly, the global stability of the controlled system is guaranteed.The well known weighting parameters approach, is used in this paper to optimize local and global approximation and modeling capability of T-S fuzzy model.A one link robot is chosen as a nonlinear unstable system to evaluate the robustness, effectiveness and remarkable performance of optimization approach and the high accuracy obtained in approximating nonlinear systems in comparison with the original T-S model. Simulation results indicate the potential and generality of the algorithm. The application of the proposed FLC-VSC shows that both alleviation of chattering and robust performance are achieved with the proposed FLC-VSC controller. The effectiveness of the proposed controller is proven infront of disturbances and noise effects. 相似文献
136.
基于RBAC权限管理模型在OA系统中的运用 总被引:2,自引:0,他引:2
分析了传统的RBAC权限管理模型,并根据国内企业的需求和特点,在RBAC的基础上设计了更灵活的权限管理机制,很好的满足了企业的需求。 相似文献
137.
数据校验是数据挖掘与知识发现中的重要一环。我国土壤观测数据由于台站观测人员上网条件、观测地记录不便以及需要适当的数据预处理等原因,无法实行在线入库,一般借助于Excel等软件来记录中间结果,再提交土壤分中心,这样的记录过程经常引入不必要的错误。提出了一个基于可定制规则库的土壤数据校验模型。模型主要包括数据格式转换模块、权限管理模块、元数据管理模块、重复记录去除模块、数据校验模块及规则定制与解析模块。低侵入式的轻量级设计,使得在大大减轻数据校验人员工作量的情况下,原有的数据填报流程不需要改变。可定制规则使得模型易于扩展。 相似文献
138.
本文以微控制器AT91RM9200和EP1C6Q240C8为核心,对工业CT机的运动控制器进行了设计,从硬件和软件两个方面对控制器的关键技术进行研究与设计,应用单神经元自适应PID控制算法进行仿真,并给出系统实际运行结果。 相似文献
139.
本文简述了安钢信息化建设概况,介绍了安钢信息化建设中开发SAP预留系统的设计流程,阐述了预留系统实现的功能. 相似文献
140.
任锋锋 《计算机光盘软件与应用》2011,(6)
随着信息技术时代带来的全新技术和革命,社会对计算机应用人才的质量要求是越来越高.中职教育作为计算机专业人才培养的一部分.如何提高学生的专业素质是目前广大教师亟待解决的问题,而计算机专业的设置和内容以及教育方法,应该得到足够的重视.另外提高学生计算机知识水平和实践动手能力,是职业学校计算机教育的根本任务.把计算机理论教学和实践教学有机地结合起来,笔者认为,"以项目为导向的3W1H教学法"是一个实用有效的好方法. 相似文献