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81.
In order to characterize the non-Gaussian information contained within the EEG signals, a new feature extraction method based on bispectrum is proposed and applied to the classification of right and left motor imagery for developing EEG-based brain-computer interface systems. The experimental results on the Graz BCI data set have shown that based on the proposed features, a LDA classifier, SVM classifier and NN classifier outperform the winner of the BCI 2003 competition on the same data set in terms of either the mutual information, the competition criterion, or misclassification rate. 相似文献
82.
A new efficient image codec called embedded wavelet coding based on list structure (EWCBL) is proposed in this paper. By combining the techniques of morphological representation and quadtree partitioning, EWCBL effectively exploits both within-subband clustering and cross-subband similarity of wavelet coefficients. Based on the list structure, a fine fractional bit-plane coding is employed to achieve excellent rate-distortion performance. The patterned morphological dilation is introduced to greatly reduce the redundant test operations. Experimental results show that the proposed EWCBL outperforms state-of-the-art embedded codecs for both lossy and lossless compression. Moreover, the good performance and features of embeddedness and scalability are achieved with relatively low complexity. 相似文献
83.
Zhou Shang-Ming Gan John Q. 《Knowledge and Data Engineering, IEEE Transactions on》2009,21(8):1191-1204
In this paper, a method for constructing Takagi-Sugeno (TS) fuzzy system from data is proposed with the objective of preserving TS submodel comprehensibility, in which linguistic modifiers are suggested to characterize the fuzzy sets. A good property held by the proposed linguistic modifiers is that they can broaden the cores of fuzzy sets while contracting the overlaps of adjoining membership functions (MFs) during identification of fuzzy systems from data. As a result, the TS submodels identified tend to dominate the system behaviors by automatically matching the global model (GM) in corresponding subareas, which leads to good TS model interpretability while producing distinguishable input space partitioning. However, the GM accuracy and model interpretability are two conflicting modeling objectives, improving interpretability of fuzzy models generally degrades the GM performance of fuzzy models, and vice versa. Hence, one challenging problem is how to construct a TS fuzzy model with not only good global performance but also good submodel interpretability. In order to achieve a good tradeoff between GM performance and submodel interpretability, a regularization learning algorithm is presented in which the GM objective function is combined with a local model objective function defined in terms of an extended index of fuzziness of identified MFs. Moreover, a parsimonious rule base is obtained by adopting a QR decomposition method to select the important fuzzy rules and reduce the redundant ones. Experimental studies have shown that the TS models identified by the suggested method possess good submodel interpretability and satisfactory GM performance with parsimonious rule bases. 相似文献
84.
一个新的基于权限的委托模型CPPBDM 总被引:1,自引:0,他引:1
基于权限的委托模型PBDM实现了权限的委托,其实现方法是将角色进行划分,使组织的角色继承关系变得复杂,模型的实现和管理变得烦琐.为此,提出对PBDM进行改进的基于权限划分的新模型CPPBDM,模型引入新的角色间关系:委托继承、激活指派;新模型能够实现基于权限的委托与角色代理,简化了模型的实现与管理. 相似文献
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87.
Youyu Duan Yang Wang Weixuan Zhang Jiangwei Zhang Chaogang Ban Danmei Yu Kai Zhou Jinjing Tang Xu Zhang Xiaodong Han Liyong Gan Xiaoping Tao Xiaoyuan Zhou 《Advanced functional materials》2023,33(28):2301729
Photocatalytic conversion of CO2 into fuels using pure water as the proton source is of immense potential in simultaneously addressing the climate-change crisis and realizing a carbon-neutral economy. Single-atom photocatalysts with tunable local atomic configurations and unique electronic properties have exhibited outstanding catalytic performance in the past decade. However, given their single-site features they are usually only amenable to activations involving single molecules. For CO2 photoreduction entailing complex activation and dissociation process, designing multiple active sites on a photocatalyst for both CO2 reduction and H2O dissociation simultaneously is still a daunting challenge. Herein, it is precisely construct Cu single-atom centers and two-coordinated N vacancies as dual active sites on CN (Cu1/N2CV-CN). Experimental and theoretical results show that Cu single-atom centers promote CO2 chemisorption and activation via accumulating photogenerated electrons, and the N2CV sites enhance the dissociation of H2O, thereby facilitating the conversion from COO* to COOH*. Benefiting from the dual-functional sites, the Cu1/N2CV-CN exhibits a high selectivity (98.50%) and decent CO production rate of 11.12 µmol g−1 h−1. An ingenious atomic-level design provides a platform for precisely integrating the modified catalyst with the deterministic identification of the electronic property during CO2 photoreduction process. 相似文献
88.
A Mussel‐Inspired Conductive,Self‐Adhesive,and Self‐Healable Tough Hydrogel as Cell Stimulators and Implantable Bioelectronics 下载免费PDF全文
89.
为了满足辐射防护的要求以及发展结构功能一体化柔性防护材料的需求,研制了一种新型的橡塑合金复合防护材料。通过力学性能和屏蔽性能测试发现,该复合材料具有较高的拉伸强度与断裂伸长率,且材料的中子与伽马屏蔽性能良好,随着功能填料含量的不断增加,中子和伽马屏蔽性能也不断提升,但材料的拉伸强度和断裂伸长率不断减小。辐照实验显示,电子束硫化后的样品比硫磺硫化后的样品拥有更出色的力学性能。综合考虑该材料良好的中子与伽马屏蔽性能、拉伸性能与柔韧性能等特性,其在形状较为复杂的核动力设施以及辐射防护服等领域具有较大的应用潜力。 相似文献
90.
Green Synthesis of Hierarchically Porous Carbon Nanotubes as Advanced Materials for High‐Efficient Energy Storage 下载免费PDF全文
Jian‐Gan Wang Hongzhen Liu Xingyuan Zhang Xu Li Xingrui Liu Feiyu Kang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(13)
Hierarchically porous carbon nanomaterials with well‐defined architecture can afford a promising platform for effectively addressing energy and environmental concerns. Herein, a totally green and straightforward synthesis strategy for the fabrication of hierarchically porous carbon nanotubes (HPCNTs) by a simple carbonization treatment without any assistance of soft/hard templates and activation procedures is demonstrated. A high specific surface area of 1419 m2 g?1 and hierarchical micro‐/meso‐/macroporosity can be achieved for the HPCNTs. The unique porous architecture enables the HPCNTs serving as excellent electrode/host materials for high‐performance supercapacitors and Li–sulfur batteries. The design strategy may pave a new avenue for the rational synthesis of hierarchically porous carbon nanostructures for high‐efficient energy storage applications. 相似文献