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《Expert systems with applications》2014,41(16):7161-7170
The features extracted from the cardiac sound signals are commonly used for detection and identification of heart valve disorders. In this paper, we present a new method for classification of cardiac sound signals using constrained tunable-Q wavelet transform (TQWT). The proposed method begins with a constrained TQWT based segmentation of cardiac sound signals into heart beat cycles. The features obtained from heart beat cycles of separately reconstructed heart sounds and murmur can better represent the various types of cardiac sound signals than that from containing both. Therefore, heart sounds and murmur have been separated using constrained TQWT. Then the proposed novel raw feature set has been created by the parameters that have been optimized while constraining the output of TQWT together with that of extracted by using time-domain representation and Fourier–Bessel (FB) expansion of separated heart sounds and murmur. However, the adaptively selected features have been used to obtain the final feature set for subsequent classification of cardiac sound signals using least squares support vector machine (LS-SVM) with various kernel functions. The performance of the proposed method has been validated with publicly available datasets and the results have been compared with the existing short-time Fourier transform (STFT) based method. The proposed method shows higher percentage classification accuracy of 94.01 as compared to 93.53 of STFT based method. In comparison with STFT based method, it is noteworthy that the proposed method uses well defined and lower dimensionality of feature vector that can reduce the computational complexity. 相似文献
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The purpose of the present study was to examine the prevalence of cyber-bullying through Facebook in a sample of 226 Greek university undergraduates, and to explore whether big five personality characteristics, narcissism, as well as attitudes toward Facebook, technological knowledge and skills were predictive of such behavior. Participants completed a self-report questionnaire measuring the above constructs. Results indicated that almost one third of the sample reported Facebook bullying engagement at least once during the past month, with male students reporting more frequent involvement than females. Bullying through Facebook was predicted by low Agreeableness and more time spent on Facebook only for males, whereas for females none of the studied variables predicted engagement in Facebook bullying. Findings are discussed in terms of prevention and intervention strategies. 相似文献
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Jianer Chen Qilong FengYang Liu Songjian LuJianxin Wang 《Theoretical computer science》2011,412(23):2503-2512
Based on the method of (n,k)-universal sets, we present a deterministic parameterized algorithm for the weighted rd-matching problem with time complexity O∗(4(r−1)k+o(k)), improving the previous best upper bound O∗(4rk+o(k)). In particular, the algorithm applied to the unweighted 3d-matching problem results in a deterministic algorithm with time O∗(16k+o(k)), improving the previous best result O∗(21.26k). For the weighted r-set packing problem, we present a deterministic parameterized algorithm with time complexity O∗(2(2r−1)k+o(k)), improving the previous best result O∗(22rk+o(k)). The algorithm, when applied to the unweighted 3-set packing problem, has running time O∗(32k+o(k)), improving the previous best result O∗(43.62k+o(k)). Moreover, for the weighted r-set packing and weighted rd-matching problems, we give a kernel of size O(kr), which is the first kernelization algorithm for the problems on weighted versions. 相似文献
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We show that for some special functions (called k-multigrid equidistributed functions), we can compute the limit of the frequency of patterns in the discretization of their graph, when the resolution tends to zero. This result is applied to parabolas. We deduce also that local length estimators almost never converge to the length for the parabolas. 相似文献
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该文设计的淋浴节水控制器,可根据消费者实际的洗浴时间长短计时收费,实现节能节水.采用RC500作为IC卡操作模块.经485接口与微机进行实时通信.采用先扣钱后供水的消费模式.定时收费,费率可通过软件设置.在空闲模式下,控制器显示当前时间;在淋浴过程中,显示消费金额及卡中余额,并可以通过红外传感器,根据需要暂停出水及计费... 相似文献
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Density functional calculations and minimization techniques have been employed to characterize the structural and electronic properties of [5,6]-heterofullerene-C58Si-C2v. Since it has odd number of atoms and a near planar tetracoordinate Si atom on the skeleton of the cage, it has odd number of atoms assembling a cage and is a novel molecule. Vibrational frequencies of the molecule have been calculated at the B3LYP/6-31G* level of theory. The absence of imaginary vibrational frequency confirms that the molecule corresponds to a true minimum on the potential energy hypersurface. Sixteen 13C nuclear magnetic resonance (NMR) spectral signals of C58Si are characterized, and its heat of formation was estimated in this work. 相似文献
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简要的介绍了循环流化床锅炉以及其保护系统FSSS的基本知识。以越南林同铝厂热电站的DCS控制系统项目为背景较为详细地介绍了如何在Honeywell的DCS系统中实现FSSS系统的功能,并且对FSSS系统的具体逻辑实现进行了详细的讲解。 相似文献