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排序方式: 共有7223条查询结果,搜索用时 172 毫秒
131.
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
132.
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
133.
针对当前嵌入式设备输入方法存在的高成本低体验问题,提出了一种运行于嵌入式系统中基于数字图像处理的虚拟输入方法.该方法利用嵌入式设备附加的摄像设备,对用户在虚拟键盘上的按键过程进行图像采集,通过角点识别和图像分割进行按键识别,以便通过采集到的图像定位出用户点击的目标按键,从而实现信息输入过程.通过实例验证了该方法的可行性... 相似文献
134.
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
135.
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
136.
Web信息检索技术已经在全世界广泛应用,然而,搜索引擎的查全率和查准率却不能够令用户满意,因此提出了一种基于通用本体WordNet的语义层次结构.通过计算和分析查询关键字与本体库的映射达到查询优化的目的.该方法通过建立一个简单的语法树并且索引WordNet,对查询关键字词法特性和本体实例之间语义关联强弱进行扩展和分析,提高了查询关键字到本体概念映射的完整性和准确率,进而帮助搜索引擎对用户的意图作出有效推测.实验表明,该方法可以有效地优化查询. 相似文献
137.
138.
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
139.
投影四面体法需要对四面体集合进行逐帧排序,而相邻四面体之间的顺序制约和依赖性限制了并行排序的效率.基于以上问题,提出一种视点相关的、基于逻辑切割的快速四面体集合精确排序方法.该方法分为4个串行步骤:首先沿视线方向将四面体集合所在空间剖分成一列有序的深度区间,每个区间包含一组四面体子集;然后并行地对每个区间的子集逐层提取互不遮挡的四面体,完成精确排序;再将区间边界上的四面体进行逻辑切割,并采用分段积分计算所有四面体在区间内的颜色贡献;最后按序沿视线方向累积所有区间的颜色贡献.实验结果表明,文中方法提高了四面体拓扑排序的并行度,极大地降低了排序时间,并大幅度地改进了绘制效率. 相似文献
140.
TMS320F2812中断系统分析及其C语言编程 总被引:1,自引:0,他引:1
中断处理是DSP应用系统中必不可少的一个重要环节。本文阐述DSP芯片TMS320F2812的中断机制和中断处理过程,并给出用C语言编程实现中断处理过程的思路和实例。 相似文献