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81.
Real-time removal of ocular artifacts from EEG based on independent component analysis and manifold learning 总被引:1,自引:1,他引:0
Junfeng Gao Pan Lin Yong Yang Pei Wang Chongxun Zheng 《Neural computing & applications》2010,19(8):1217-1226
Frequent occurrence of ocular artifacts leads to serious problems in interpreting and analyzing the electroencephalogram (EEG).
In the present paper, a novel and robust technique is proposed to eliminate ocular artifacts from EEG signals in real time.
Independent Component Analysis (ICA) is used to decompose EEG signals. The features of topography and power spectral density
of those components are extracted. Moreover, we introduce manifold learning algorithm, a recently popular dimensionality reduction
technique, to reduce the dimensionality of initial features, and then those new features are fed to a classifier to identify
ocular artifacts components. A k-nearest neighbor classifier is adopted to classify components because classification results
show that manifold learning with the nearest neighbor algorithm works best. Finally, the artifact removal method proposed
here is evaluated by the comparisons of EEG data before and after artifact removal. The results indicate that the method proposed
could remove ocular artifacts effectively from EEG signals with little distortion of the underlying brain signals and be satisfied
the real-time application. 相似文献
82.
Kuo-Liang Chung Soo-Chang Pei Ying-Lin Pan Wei-Ling Hsu Yong-Huai Huang Wei-Ning Yang Chyou-Hwa Chen 《Expert systems with applications》2011,38(3):1591-1601
This paper presents a gradient-based adaptive error diffusion method with edge enhancement effect while preserving the smoothness effect. The proposed method not only can modulate the threshold in halftoning dynamically but also can determine the weights of the error diffusion filter adaptively to diffuse the quantization error to neighboring pixels properly. Under six testing images, experimental results demonstrate that our proposed new error diffusion method has a good compromise between the edge enhancement effect in the halftone image and the image quality effect in the corresponding inverse halftone image when compared to the methods by Floyd–Steinberg, Eschbach and Knox, Hwang et al., Li, and Feng et al., but it has some execution-time degradation. 相似文献
83.
Tairen Sun Hailong Pei Yongping Pan Hongbo Zhou Caihong Zhang 《Neurocomputing》2011,74(14-15):2377-2384
This paper addresses the robust trajectory tracking problem for a robot manipulator in the presence of uncertainties and disturbances. First, a neural network-based sliding mode adaptive control (NNSMAC), which is a combination of sliding mode technique, neural network (NN) approximation and adaptive technique, is designed to ensure trajectory tracking by the robot manipulator. It is shown using the Lyapunov theory that the tracking error asymptotically converge to zero. However, the assumption on the availability of the robot manipulator dynamics is not always practical. So, an NN-based adaptive observer is designed to estimate the velocities of the links. Next, based on the observer, a neural network-based sliding mode adaptive output feedback control (NNSMAOFC) is designed. Then it is shown by the Lyapunov theory that the trajectory tracking errors, the observer estimation errors asymptotically converge to zero. The effectiveness of the designed NNSMAC, the NN-based adaptive observer and the NNSMAOFC is illustrated by simulations. 相似文献
84.
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87.
Chen Wenshuo Ding Guiguang Lin Zijia Pei Jisheng 《Multimedia Tools and Applications》2017,76(2):2441-2466
Multimedia Tools and Applications - Hashing is a binary-code encoding method which tries to preserve the neighborhood structures in the original feature space, in order to realize efficient... 相似文献
88.
介绍了串行外设接口SPI的通信原理,对RT Thread操作系统下的SPI总线驱动结构进行了详细的研究与分析.以STM32F407ZG对W25Q64的读写为例,介绍了硬件SPI总线驱动的移植步骤,并详细介绍了SPI应用程序设计及技术实施细节.最后通过实验,对SPI驱动移植及程序设计的可行性及有效性进行验证,实验结果表明,RT Thread操作系统下的SPI总线驱动结构设计合理,移植方便且应用程序设计简单,本文所介绍的移植与应用方法可行有效. 相似文献
89.
Yin P Criminisi A Winn J Essa I 《IEEE transactions on pattern analysis and machine intelligence》2011,33(1):30-42
This paper presents an automatic segmentation algorithm for video frames captured by a (monocular) webcam that closely approximates depth segmentation from a stereo camera. The frames are segmented into foreground and background layers that comprise a subject (participant) and other objects and individuals. The algorithm produces correct segmentations even in the presence of large background motion with a nearly stationary foreground. This research makes three key contributions: First, we introduce a novel motion representation, referred to as "motons," inspired by research in object recognition. Second, we propose estimating the segmentation likelihood from the spatial context of motion. The estimation is efficiently learned by random forests. Third, we introduce a general taxonomy of tree-based classifiers that facilitates both theoretical and experimental comparisons of several known classification algorithms and generates new ones. In our bilayer segmentation algorithm, diverse visual cues such as motion, motion context, color, contrast, and spatial priors are fused by means of a conditional random field (CRF) model. Segmentation is then achieved by binary min-cut. Experiments on many sequences of our videochat application demonstrate that our algorithm, which requires no initialization, is effective in a variety of scenes, and the segmentation results are comparable to those obtained by stereo systems. 相似文献
90.