University of Electronic Science and Technology of China

About: University of Electronic Science and Technology of China is a education organization based out in Chengdu, China. It is known for research contribution in the topics: Computer science & Antenna (radio). The organization has 50594 authors who have published 58502 publications receiving 711188 citations. The organization is also known as: UESTC.

Fuzzy SVM with a new fuzzy membership function

Abstract: It is known that with a proper fuzzy membership function, a fuzzy support vector machine can effectively reduce the effects of outliers when solving the classification problem. In this paper, a new fuzzy membership function is proposed to the nonlinear fuzzy support vector machine. The fuzzy membership is calculated in the feature space and is represented by kernels. This method gives good performance on reducing the effects of outliers and significantly improves the classification accuracy and generalization.

Porous Si Nanowires from Cheap Metallurgical Silicon Stabilized by a Surface Oxide Layer for Lithium Ion Batteries

Abstract: In the quest to develop next generation lithium ion battery anode materials, satisfactory electrochemical performance and low material/fabrication cost are the most desirable features. In this article, porous Si nanowires are synthesized by a cost-effective metal-assisted chemical etching method using cheap metallurgical silicon as feedstock. More importantly, a thin oxide layer (≈3 nm) formed on the surface of porous Si nanowires stabilizes the cycling performance of lithium ion batteries. Such an oxide coating is able to constrain the huge volume expansion of the underlying Si, yet it is thin enough to ensure good permeability for both lithium ions and electrons. Therefore, the extraordinary storage capacity of Si can be well retained in prolonged electrochemical cycles. Specifically, Si/SiOx nanowires deliver a reversible capacity of 1503 mAh g−1 at the 560th cycle at a current density of 600 mA g−1, demonstrating an average of only 0.04% drop per cycle compared with its initial capacity. Furthermore, the highly porous structure and thin Si wall facilitate the electrolyte penetration and shorten the solid-state lithium transportation path, respectively. As a result, stable and satisfactory reversible capacities of 1297, 976, 761, 548, and 282 mAh g−1 are delivered at current densities of 1200, 2400, 3600, 4800, and 7200 mA g−1, respectively.

Large-Scale Multi-View Subspace Clustering in Linear Time

Abstract: A plethora of multi-view subspace clustering (MVSC) methods have been proposed over the past few years. Researchers manage to boost clustering accuracy from different points of view. However, many state-of-the-art MVSC algorithms, typically have a quadratic or even cubic complexity, are inefficient and inherently difficult to apply at large scales. In the era of big data, the computational issue becomes critical. To fill this gap, we propose a large-scale MVSC (LMVSC) algorithm with linear order complexity. Inspired by the idea of anchor graph, we first learn a smaller graph for each view. Then, a novel approach is designed to integrate those graphs so that we can implement spectral clustering on a smaller graph. Interestingly, it turns out that our model also applies to single-view scenario. Extensive experiments on various large-scale benchmark data sets validate the effectiveness and efficiency of our approach with respect to state-of-the-art clustering methods.

Max-Ratio Relay Selection in Secure Buffer-Aided Cooperative Wireless Networks

Abstract: This paper considers the security of transmission in buffer-aided decode-and-forward cooperative wireless networks. An eavesdropper which can intercept the data transmission from both the source and relay nodes is considered to threaten the security of transmission. Finite size data buffers are assumed to be available at every relay in order to avoid having to select concurrently the best source-to-relay and relay-to-destination links. A new max-ratio relay selection policy is proposed to optimize the secrecy transmission by considering all the possible source-to-relay and relay-to-destination links and selecting the relay having the link which maximizes the signal to eavesdropper channel gain ratio. Two cases are considered in terms of knowledge of the eavesdropper channel strengths: exact and average gains, respectively. Closed-form expressions for the secrecy outage probability for both cases are obtained, which are verified by simulations. The proposed max-ratio relay selection scheme is shown to outperform one based on a max-min-ratio relay scheme.