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Zhou Y.-J.,Beijing University of Posts and Telecommunications | Zhou Y.-J.,Science and Technology on Electronic Control Laboratory | Liu K.,Beihang University | Xiao L.,Beihang University
Tongxin Xuebao/Journal on Communications | Year: 2012

A weighted cooperative spectrum sensing algorithm based on D-S evidence theory (DS-WCSS) was proposed. The algorithm took energy detector to perform local spectrum sensing, evaluated the credibility difference of cognitive users according to the means and variances of test statistic in both hypotheses, set credibility weights based on the evaluation of credibility difference, and finally used D-S evidence theory to fuse data and made a decision. Simulation results show that the proposed algorithm has better performance than cooperative spectrum sensing algorithm based on D-S evidence theory and traditional hard-decisions.


Zhou Y.-J.,Beijing University of Posts and Telecommunications | Zhou Y.-J.,Science and Technology on Electronic Control Laboratory | Xue C.,Beijing University of Posts and Telecommunications | Ping Y.,Beijing University of Posts and Telecommunications | Ping Y.,Xuchang University
Beijing Gongye Daxue Xuebao/Journal of Beijing University of Technology | Year: 2013

To make the network administrators to monitor and manage P2P traffic data efficiently, a port feature based P2P application identification method was proposed, following with the analysis of behavioral characteristics of diverse P2P applications. In the proposed method, both of the packet length and the distribution of packet size with respect to each UDP port were employed to form a vector for each P2P application, and then the work of P2P application identification could be done effectively by a machine learning method, i.e., support vector machine. Results show that the proposed method can distinguish the different P2P applications effectively, especially for the video applications which can be achieved for a precision of 99.91%.


Zhou J.-X.,Beijing University of Posts and Telecommunications | Zhou J.-X.,National Engineering Laboratory for Disaster Backup and Recovery | Li H.,Science and Technology on Electronic Control Laboratory | Zhou Y.-J.,Beijing University of Posts and Telecommunications | And 5 more authors.
Dianzi Yu Xinxi Xuebao/Journal of Electronics and Information Technology | Year: 2012

Radio Frequency IDentification (RFID) tag search protocols are used in a situation where an reader finds a specific tag among multiple tags, which play important roles in many RFID applications. However, the existing protocols either have security weaknesses or exhibit poor efficiency. In this paper, a server-less RFID tag secure search protocol is proposed, which utilizes hash function and timestamp. GNY logic is used to prove its correctness. Analysis shows that presented protocol can be used to search a particular tag efficiently, and preserve tag's privacy against all major attacks.


Ping Y.,Beijing University of Posts and Telecommunications | Ping Y.,Xuchang University | Ping Y.,Science and Technology on Electronic Control Laboratory | Zhou Y.-J.,Beijing University of Posts and Telecommunications | And 2 more authors.
Journal of China Universities of Posts and Telecommunications | Year: 2012

An effective text representation scheme dominates the performance of text categorization system. However, based on the assumption of independent terms, the traditional schemes which tediously use term frequency (TF) and document frequency (DF) are insufficient for capturing enough information of a document and result in poor performance. To overcome this limitation, we investigate exploring the relationships between different terms of the same class tendency and the way of measuring the importance of a repetitive term in a document. In this paper, a group of novel term weighting factors are proposed to enhance the category contribution for each term. Then, based on a novel strategy of generating passages from document, we present two schemes, the weighted co-contributions of different terms corresponding to the class tendency and the weighted co-contributions for each term in different passages, to achieve improvements on text representation. The prior scheme works in a dimensionality reduction mode while the second one runs in the conventional way. By employing the support vector machine (SVM) classifier, experiments on four benchmark corpora show that the proposed schemes could achieve a consistent better performance than the conventional methods in both efficiency and accuracy. Further analysis also confirms some promising directions for the future works. © 2012 The Journal of China Universities of Posts and Telecommunications.


Hou Y.,Wuhan University of Technology | Hou Y.,Science and Technology on Electronic Control Laboratory | Chen H.,Science and Technology on Electronic Control Laboratory | Chen H.,Key Research Laboratory Radar Academy | And 2 more authors.
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

In this paper, a direction-of-arrival (DOA) estimation method for resolving correlation by spatial averaging algorithm based on the horizontally Uniform Circular Array (UCA) is presented. The ambiguity resolution method is proposed for the appearing of the third-order ambiguity on the horizontally UCA. Restructuring the covariance matrix of the received data again, the angle of the sub-arrays will be changed. Finally, the DOA estimation performance of the new algorithm is studied, including the effects of the Signal-to-Noise Ratio (SNR) and the numbers of the snapshots to the performance and further analyzes the effects of imperfections, such as amplitude error and the phase error. © 2012 Springer-Verlag.

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