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101.
深入分析了论域变化与决策表条件信息熵的变化原理,在此基础上提出一种新的决策表属性约简算法. 该算法通过不断将决策表中一定属性集下协调的部分从论域中去除,把不协调的部分作为新的论域做进一步处理,逐步减少参与属性约简的对象数,可以在一定程度上降低求取属性约简的计算量,实验数据表明该算法是高效的. 相似文献
102.
Zengyun Wang Lihong Huang Yi Zuo Lingling Zhang 《International Journal of Control, Automation and Systems》2010,8(2):266-271
This paper considers the H ∞ control problem for the uncertain time delay system with nonlinear external disturbance. Given a system containing nonlinear external disturbance, our purpose is to design a robust controller such that the uncertain system is asymptotically stable with a generalized H ∞ disturbance attenuation level ρ. In this paper we propose a new approach to design the controller for the uncertain system which is composed of a linear controller and an adaptive controller. The problem is solved by introducing a switching function and using the idea of formulation. Based on Lyapunov stability theory, new sufficient conditions are obtained in terms of linear matrix inequalities. The effectiveness and advantages of the proposed controller design are shown via a numerical example. 相似文献
103.
This paper addresses the analysis problem of asymptotic stability for a class of uncertain neural networks with Markovian jumping parameters and time delays. The considered transition probabilities are assumed to be partially unknown. The parameter uncertainties are considered to be norm-bounded. A sufficient condition for the stability of the addressed neural networks is derived, which is expressed in terms of a set of linear matrix inequalities. A numerical example is given to verify the effectiveness of the developed results. 相似文献
104.
This paper investigates the methodologies for locating and identifying components on a printed circuit board (PCB) used for
surface mount device inspection. It’s the foundation of other inspections, such as solder joint inspection, component type
recognization and so on. The proposed scheme consists of two stages: solder joint extraction and protective coating extraction.
This work uses automatic multilevel thresholding approach for detecting specular areas which contain solder joints. Some invalid
specular areas, such as markings and via-holes are recognized and removed by comparing the colour distribution features of
the target objects and the reference objects. A novel approach based on connection graph and the segmented gray-scale PCB
images is developed to classify all recognized solder joints as several clusters. And then, the protective coating is extracted
by the positions of the clustered solder joints. Experimental results show that the proposed method can recognize most of
components effectively. 相似文献
105.
A robust scheduling method is proposed to solve uncertain scheduling problems. An uncertain scheduling problem is modeled by a set of workflow models, and then a scheduling scheme (solution) of the problem can be evaluated by workflow simulations executed with the workflow models in the set. A multi-objective immune algorithm is presented to find Pareto optimal robust scheduling schemes that have good performance for each model in the set. The two optimization objectives for scheduling schemes are the indices of the optimality and robustness of the scheduling results. An antibody represents a resource allocation scheme, and the methods of antibody coding and decoding are designed to deal with resource conflicts during workflow simulations. Experimental tests show that the proposed method can generate a robust scheduling scheme that is insensitive to uncertain scheduling environments. 相似文献
106.
Heng Qi Yuhong Liu Xuan Wang Feng Shen Yong Yu Tao Chen Tiechuan Zuo 《Microsystem Technologies》2009,15(2):297-300
Excimer laser ablation technique was introduced into this work to fabricate a passive planar micromixer on the PMMA substrate.
T-junction shaped and width-changed S-shaped microchannels were both designed in this micromixer to enhance mixing effect.
The mixing experiment of distilled water and Rhodamine B with injection flow rate of 500 and 1,500 μm/s validates the mixing
effectivity of this micromixer, and indicates the feasibility of excimer laser ablation in the microfabrication of μ-TAS device. 相似文献
107.
This paper investigates the robust finite-time consensus problem of multi-agent systems in networks with undirected topology. Global nonlinear consensus protocols augmented with a variable structure are constructed with the aid of Lyapunov functions for each single-integrator agent dynamics in the presence of external disturbances. In particular, it is shown that the finite settling time of the proposed general framework for robust consensus design is upper bounded for any initial condition. This makes it possible for network consensus problems to design and estimate the convergence time offline for a multi-agent team with a given undirected information flow. Finally, simulation results are presented to demonstrate the performance and effectiveness of our finite-time protocols. 相似文献
108.
基于多虚空间多重映射技术的并行操作系统 总被引:3,自引:0,他引:3
高性能计算机系统的可扩展性是系统设计的一大难题,NUMA(non-uniformmemoryarchitecture)结构正是为了解决共享存储体系的可扩展性问题而提出来的.研究和实践表明,整机系统的可扩展性与操作系统的结构有着密切的关系.典型的多处理机操作系统通常采用两种结构,基于共享的单一核心结构以及基于消息的多核心结构.通过分析得出结论认为,这两种结构都不能很好地适应可扩展并行机尤其是NUMA结构并行机的需求.针对存在的问题,提出了新的结构设计思想:多虚空间多重映射与主动消息相结合.测试和运行结果显示,该结构成功地解决了系统的可扩展问题. 相似文献
109.
SPI接口技术及应用 总被引:7,自引:0,他引:7
本文详细介绍了SPI接口芯片的逻辑时序,给出了实时硬件接口的连接方式,并对编程实现时的注意事项进行了说明。 相似文献
110.