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171.
机电阻抗技术是一种新兴的非参数结构健康监测方法,对结构局部微缺陷比较敏感;为了实现基于机电阻抗技术的结构健康监测,采用Visual C++和Matlab混合编程的方式设计和开发了系统监测软件;该软件用于控制现场的无线智能机电阻抗传感器进行数据采集,同时对测量数据进行处理,根据损伤评估算法评定结构健康状况;软件采用Visual C++编写系统人机交互界面和通信接口程序,采用Matlab编写数据处理和损伤评估算法,同时图形化输出运算结果;将两者的优势有机结合,从而缩短了软件的开发周期。 相似文献
172.
Eye gaze tracking is very useful for quantitatively measuring visual attention in virtual environments. However, most eye
trackers have a limited tracking range, e.g., ±35° in the horizontal direction. This paper proposed a method to combine head
pose tracking and eye gaze tracking together to achieve a large range of tracking in virtual driving simulation environments.
Multiple parallel multilayer perceptrons were used to reconstruct the relationship between head images and head poses. Head
images were represented with the coefficients extracted from Principal Component Analysis. Eye gaze tracking provides precise
results on the front view, while head pose tracking is more suitable for tracking areas of interest than for tracking points
of interest on the side view. 相似文献
173.
Yiqiao Cai Jiahai Wang Jian Yin 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(2):303-330
Differential evolution (DE) is a simple and powerful population-based search algorithm, successfully used in various scientific
and engineering fields. However, DE is not free from the problems of stagnation and premature convergence. Hence, designing
more effective search strategies to enhance the performance of DE is one of the most salient and active topics. This paper
proposes a new method, called learning-enhanced DE (LeDE) that promotes individuals to exchange information systematically.
Distinct from the existing DE variants, LeDE adopts a novel learning strategy, namely clustering-based learning strategy (CLS).
In CLS, there are two levels of learning strategies, intra-cluster learning strategy and inter-cluster learning strategy.
They are adopted for exchanging information within the same cluster and between different clusters, respectively. Experimental
studies over 23 benchmark functions show that LeDE significantly outperforms the conventional DE. Compared with other clustering-based
DE algorithms, LeDE can obtain better solutions. In addition, LeDE is also shown to be significantly better than or at least
comparable to several state-of-art DE variants as well as some other evolutionary algorithms. 相似文献
174.
A population protocol is one of distributed computing models for passively-mobile systems, where a number of agents change
their states by pairwise interactions between two agents. In this paper, we investigate the solvability of the self-stabilizing
leader election in population protocols without any kind of oracles. We identify the necessary and sufficient conditions to
solve the self-stabilizing leader election in population protocols from the aspects of local memory complexity and fairness
assumptions. This paper shows that under the assumption of global fairness, no protocol using only n−1 states can solve the self-stabilizing leader election in complete interaction graphs, where n is the number of agents in the system. To prove this impossibility, we introduce a novel proof technique, called closed-set
argument. In addition, we propose a self-stabilizing leader election protocol using n states that works even under the unfairness assumption. This protocol requires the exact knowledge about the number of agents
in the system. We also show that such knowledge is necessary to construct any self-stabilizing leader election protocol. 相似文献
175.
提出一种基于码本模型和多特征的早期烟雾检测算法。首先,利用码本模型进行前景提取;然后,结合烟雾的颜色模型和形状特征模型检测前景中的疑似烟雾区域;最后,利用烟雾的动态特性,有效地降低误检率,提高算法的鲁棒性。通过ROC曲线对比,实验结果表明,该算法具有良好的烟雾检测能力。同时,能够满足实时性要求,具有较高的实用价值。 相似文献
176.
硬盘承载着重要数据,它的精密度很高,而且它内部的机械运动快速而准确。一旦这个精密装置的某一部分出现了故障,存储在里面的数据就无法访问,甚至有可能会永久丢失。修复硬盘,找回数据,是数据恢复工程师的神圣使命。一般来说,经修复的硬盘稳定性已大为下降,所以不建议继续使用。但硬盘不用后也不能随意丢弃,因为里面还存储有机密数据,应当将其数据销毁。本文就针对带有坏扇区故障硬盘的数据如何实现数据备份与销毁,以便用户能读出(或销毁)其中重要的数据。 相似文献
177.
蔡海兴 《自动化与信息工程》2012,33(1):36-39
根据便携式通信设备的特殊要求,结合某携行通信设备的研制,本文提出了一种新型便携式通信设备的设计思路和方法。首先给出便携式通信设备总体设计要求,然后从结构设计、环境适应性设计和EMC设计等多方面展开讨论。 相似文献
178.
城市道路各交叉口交通信号的配时优化和协同控制直接影响整个城市的交通状况.本文以单交叉口模型的交通信号控制问题为背景,构造了以单交叉口滞留的车辆数最少为目标的优化模型.用混沌量子进化算法进行仿真数据求解,得到实时控制的配时方案,并与其它算法的仿真结果进行比较,结果表明该算法对单交叉口的信号配时优化是非常有效的. 相似文献
179.
180.
Assessment of vitrified CBN wheels for precision grinding 总被引:3,自引:0,他引:3
Methods of measuring topographical features of grinding wheels are reviewed. Each technique has advantages and limitations for resolution, measuring depth, ease of application, data analysis and interpretation. Results obtained vary according to the method and instrument employed. Advantages and difficulties experienced with different techniques are discussed. Different replication techniques and materials are compared and suggestions made. A set of parameters that describe the wheel and grain characteristics is defined. Experimental studies with grinding wheels having different structures are carried out in terms of observations and measurements of changes in wheel topography. Experimental results are analysed and discussed in relation to theoretical understanding of abrasive wear and loading. 相似文献