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1.
《微型机与应用》2016,(21):49-51
硅钢钢带是变压器等工业设备发展的一项重要原材料,其质量的高低直接影响着产品性能的好坏。传统的人工检测具有效率低、精确度差等特点。为此提出基于机器视觉的表面缺陷自动检测研究。该研究采用图像处理及模式匹配的方法,通过对由CCD工业相机采集到的图片进行几何矫正、图像拼接、缺陷处理等过程,实现了硅钢钢带表面缺陷轮廓检测、特征提取、分类等功能,从而完成钢带质量的判定。  相似文献   

2.
针对实际环境噪声下的手机来源识别问题,提出一种基于线性判别分析和时序卷积网络的手机来源识别方法.首先,通过分析不同手机语音特征在实际环境噪声下的分类性能,基于带能量描述符、常数Q变换域和线性判别分析得到一种新的手机语音混合特征.然后,以此混合特征为输入,基于时序卷积网络进行训练和分类.最后,在10个品牌、47种手机型号...  相似文献   

3.
基于视觉仿生机理的铜带表面缺陷检测   总被引:1,自引:1,他引:0       下载免费PDF全文
受神经解剖学和心理学中有关视觉系统研究成果的启发,提出一种基于生物视觉仿生机理的铜带表面缺陷检测模型。该模型首先使用Gaussian金字塔分解和Gabor滤波器提取缺陷图像特征,合成特征显著图,然后模拟自底向上注意机制,分析视网膜中央凹的内容以获取what信息;再根据扫视仿真中访问点的时间顺序序列,即扫描路径,组成where信息流;最后利用离散的可观测马尔可夫模型,根据what信息和where信息调整相应类的单个马尔可夫链的概率,最大化训练样本的似然值,从而实现缺陷的正确分类。实验结果表明,本文算法在表面缺陷检测系统中的可行性及有效性,在多类缺陷分类中达到94.40%的总准确率。  相似文献   

4.
In this paper, by analyzing the worm’s propagation model, we propose a new worm warning system based on the method of system identification, and use recursive least squares algorithm to estimate the worm’s infection rate. The simulation result shows the method we adopted is an efficient way to conduct Internet worm warning.  相似文献   

5.
In this paper, by analyzing the worm’s propagation model, we propose a new worm warning system based on the method of system identification, and use recursive least squares algorithm to estimate the worm’s infection rate. The simulation result shows the method we adopted is an efficient way to conduct Internet worm warning.  相似文献   

6.
视频中时间域上的闪烁干扰是影响视频质量的因素之一,对闪烁干扰的准确辨识不但有利于视频质量的自动分析与诊断,而且能够与干扰去除和质量增强算法形成反馈机制,促进此类算法的自适应性。以监控视频中的闪烁干扰为研究对象,研究发现闪烁干扰信号的差分信号服从拉普拉斯分布。基于拉普拉斯分布的特性和小概率事件的思想,在视频时间域差分信号中采用迭代拟合方法,有效地分离出差分信号中影响闪烁干扰辨识的客观运动差分信号;同时,运用人眼视觉系统的最小可感知差异(JND)理论,通过量化闪烁干扰的频率和闪烁幅度得到闪烁干扰辨识指标,对闪烁干扰进行了有效的无参考辨识,并通过受试者工作特征(ROC)曲线验证了提出的无参考闪烁干扰辨识指标在正负样本的分类上具有比较理想的效果,提出的无参考算法在闪烁干扰辨识方面具有较好的性能。  相似文献   

7.
Atomic blocks, a high-level language construct that allows programmers to explicitly specify the atomicity of operations without worrying about the implementations, are a promising approach that simplifies concurrent programming. On the other hand, temporal logic is a successful model in logic programming and concurrency verification, but none of existing temporal programming models supports concurrent programming with atomic blocks yet. In this paper, we propose a temporal programming model (αPTL) which extends the projection temporal logic (PTL) to support concurrent programming with atomic blocks. The novel construct that formulates atomic execution of code blocks, which we call atomic interval formulas, is always interpreted over two consecutive states, with the internal states of the block being abstracted away. We show that the framing mechanism in projection temporal logic also works in the new model, which consequently supports our development of an executive language. The language supports concurrency by introducing a loose interleaving semantics which tracks only the mutual exclusion between atomic blocks. We demonstrate the usage of αPTL by modeling and verifying both the fine-grained and coarse-grained concurrency.  相似文献   

8.
通过分析自动信任协商系统中的行为抽象,形式化定义了协商模式.基于扩展的一阶时态逻辑给出了自动信任协商系统的抽象模型,分析了模型的语法和语义,为实现自动信任协商系统提供了有效的工具.  相似文献   

9.
Atomic blocks, a high-level language construct that allows programmers to explicitly specify the atomicity of operations without worrying about the implementations, are a promising approach that simplifies concurrent programming. On the other hand, temporal logic is a successful model in logic programming and concurrency verification, but none of existing temporal programming models supports concurrent programming with atomic blocks yet. In this paper, we propose a temporal programming model (αPTL) which extends the projection temporal logic (PTL) to support concurrent programming with atomic blocks. The novel construct that formulates atomic execution of code blocks, which we call atomic interval formulas, is always interpreted over two consecutive states, with the internal states of the block being abstracted away. We show that the framing mechanism in projection temporal logic also works in the new model, which consequently supports our development of an executive language. The language supports concurrency by introducing a loose interleaving semantics which tracks only the mutual exclusion between atomic blocks. We demonstrate the usage of αPTL by modeling and verifying both the fine-grained and coarse-grained concurrency.  相似文献   

10.
水位预测是防洪预警工作的辅助决策支持。为了进行准确的水位预测,为预防自然灾害提供科学依据,提出一种结合改进的灰狼优化(MGWO)算法与时域卷积网络(TCN)的预测模型MGWO-TCN。针对标准灰狼优化(GWO)算法存在早熟停滞的不足引入差分进化(DE)算法,扩展灰狼种群的多样性;改进灰狼种群更新时的收敛因子和变异时的变异算子,以自适应的形式对参数进行调整,提升算法的收敛速度,均衡算法的全局与局部搜索能力;利用MGWO算法对TCN的重要参数寻优,提升TCN的预测性能。将MGWO-TCN预测模型用于河流水位预测,预测结果的均方根误差(RMSE)为0.039。实验结果表明,与对比模型相比,MGWO-TCN预测模型具有更好的寻优能力和更高的预测精度。  相似文献   

11.
基于时空相关性的视频隐写分析   总被引:2,自引:0,他引:2       下载免费PDF全文
视频中的扩频嵌入是一种典型的隐写方法,能够抵抗视频压缩、噪声添加等多种攻击。为了有效检测利用该方法嵌入的隐藏信息,将隐写过程建模为加性高斯噪声的叠加过程,分析了噪声叠加对视频序列的时间相关性和空间相关性的影响,提出了基于时空相关性的隐写分析算法。该算法利用视频序列中各帧的四方向差分直方图度量隐写对空间相关性的影响,同时利用相邻帧帧间差分的直方图度量隐写对时间相关性的影响。与现有算法相比,本文算法实现简单,实验结果表明本文算法具有更好的检测性能。  相似文献   

12.
Self-learning fuzzy controllers based on temporal backpropagation   总被引:5,自引:0,他引:5  
A generalized control strategy that enhances fuzzy controllers with self-learning capability for achieving prescribed control objectives in a near-optimal manner is presented. This methodology, termed temporal backpropagation, is model-sensitive in the sense that it can deal with plants that can be represented in a piecewise-differentiable format, such as difference equations, neural networks, GMDH structures, and fuzzy models. Regardless of the numbers of inputs and outputs of the plants under consideration, the proposed approach can either refine the fuzzy if-then rules of human experts or automatically derive the fuzzy if-then rules if human experts are not available. The inverted pendulum system is employed as a testbed to demonstrate the effectiveness of the proposed control scheme and the robustness of the acquired fuzzy controller.  相似文献   

13.
We develop a theory for the temporal integration of visual motion motivated by psychophysical experiments. The theory proposes that input data are temporally grouped and used to predict and estimate the motion flows in the image sequence. This temporal grouping can be considered a generalization of the data association techniques that engineers use to study motion sequences. Our temporal grouping theory is expressed in terms of the Bayesian generalization of standard Kalman filtering. To implement the theory, we derive a parallel network that shares some properties of cortical networks. Computer simulations of this network demonstrate that our theory qualitatively accounts for psychophysical experiments on motion occlusion and motion outliers. In deriving our theory, we assumed spatial factorizability of the probability distributions and made the approximation of updating the marginal distributions of velocity at each point. This allowed us to perform local computations and simplified our implementation. We argue that these approximations are suitable for the stimuli we are considering (for which spatial coherence effects are negligible).  相似文献   

14.
极限学习机在岩性识别中的应用   总被引:3,自引:0,他引:3  
基于传统支持向量机(SVM)训练速度慢、参数选择难等问题,提出了基于极限学习机(ELM)的岩性识别.该算法是一种新的单隐层前馈神经网络(SLFNs)学习算法,不但可以简化参数选择过程,而且可以提高网络的训练速度.在确定了最优参数的基础上,建立了ELM的岩性分类模型,并且将ELM的分类结果与SVM进行对比.实验结果表明,ELM以较少的神经元个数获得与SVM相当的分类正确率,并且ELM参数选择比SVM简便,有效降低了训练速度,表明了ELM应用于岩性识别的可行性和算法的有效性.  相似文献   

15.
面对海量的非结构化时态信息,构建了在分布式环境下的数据存储模型,并在此基础上提出一种基本的时态数据处理方法。使用Hadoop平台下的分布式、非结构化数据库HBase对海量时态数据进行存储,构造以时态集合为时态存储单元的时态数据存储模型;针对分布式处理特征和时态集合数据类型,提出一种在Map/Reduce编程计算模式下进行海量时态信息关系演算的实现方法;通过扩展时态区间关系运算,实现以时态集合为基本时态数据操作对象的交、并等关系运算。以医疗时态数据作为研究实例,表明了所提出的时态数据存储模型和关系演算方案在分布式应用系统下的适用性。  相似文献   

16.
许小润  吴贵芳 《计算机应用》2010,30(8):2247-2249
针对传统的图像检测算法对具有噪声以及光照不足或不均匀的带钢表面图像检测时效果不理想的问题,提出了基于人工免疫系统的带钢表面缺陷检测技术。根据检测器和抗原之间的论域空间包含关系,以及自体在论域空间中的位置信息,引进了分块空间的方式,提出了检测器分块的生成算法,对缺陷图像表面灰度信息进行三维恢复,获得带钢表面缺陷的高度信息,实现其三维质量检测。实验表明,该方法无论是在对比度低、光照不均还是有噪声干扰的情况下相对于传统的图像检测算法具有较好的处理效果。  相似文献   

17.
焦程波 《计算机应用》2011,31(11):2965-2968
网络地址翻译器转发的混合流与P2P数据流呈现相似的流量外部特征。实际测试结果显示,如果数据捕获点位于网络地址翻译器之后,当前P2P流量特征识别方法(TLI)因为没有对网络地址翻译器(NAT)转发混合流进行区分而将导致虚警和漏报情况。为了解决此类问题,提出了基于流身份识别的P2P流量检测方法,首先通过分析IP标识时间序列完成对NAT转发混合流中源自不同设备数据流的身份识别,在此基础上采用流量特征检测P2P流量。以当前主要的P2P应用为例进行测试,结果说明,利用该方法可以有效识别NAT混合流中的P2P流量,较大幅度降低虚警率和漏报率。  相似文献   

18.
针对信道对声音信号的卷积效应,提出了一种基于粒子群优化的盲解卷积新算法。利用信号的时间可预测性作为盲解卷积的解卷测度,采用粒子群优化算法对基于该测度的代价函数进行优化求解,从而成功得到解卷积滤波器系数,实现对信号的盲解卷积。仿真实验表明,所提出的算法对于声音信号具有很好的盲解卷积效果,所恢复信号与原始信号的相关系数和重构信噪比均较高。  相似文献   

19.
针对时间序列关联规则挖掘存在时间复杂度高、效率低等问题,将基于SFVS(统计特征矢量符号化)的时间序列表示方法引入到时序关联规则发现中,利用描述时序数据统计特征的均值与方差分别作为描述其平均值及发散程度的分量,实现时间序列表示的矢量化,然后再进行动态关联规则挖掘。实验结果表明,基于该方法所获取的关联规则具有更高的精确度和可信度。  相似文献   

20.
Event-based sequences are a kind of pattern based on temporal associations with two essential characteristics: they are syntactically simple and have a great expressive power. For this reason, event-based sequence mining is an interesting solution to the problem of knowledge discovery in dynamic domains, mainly characterized by a time-varying nature. The inter-transactional model has led to the design of algorithms aimed to obtain this sort of patterns from time-stamped datasets. These algorithms extend the well-known Apriori algorithm, by explicitly adding the temporal context where associations among frequent events occurs. This leads to the possibility of extracting a larger number of patterns with a potential interest in decision making. However, its usefulness is diminished in those datasets where the characteristics of variability and uncertainty are present, which is a common issue in real domains. This is due to the rigidity of the counting method, which uses an exact measure of distance between temporal events. As a solution, we propose a generalization of the temporal mining process, which implies a relaxation of the counting method including the concept of approximate temporal distance between events. In particular, in this paper we present an algorithm, called TSETfuzzy-Miner, which incorporates a fuzzy-based counting technique in order to extract general, flexible, and practical temporal patterns taking into account the particular characteristics of real domains.  相似文献   

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