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Xiong H.,Peking University | Xiong H.,Chongqing Key Laboratory of Computer Network and Communication Technology | Xiong H.,University of Electronic Science and Technology of China | Hu J.,Peking University | And 2 more authors.
Computers and Electrical Engineering | Year: 2011

In a multi-proxy signature scheme, an original signer could authorize a proxy group as his proxy agent. Then only the cooperation of all the signers in the proxy group can generate the proxy signatures on behalf of the original signer. Recently, Cao and Cao gave the first formal definition and security model of an identity-based multi-proxy signature scheme, then proposed an identity-based multi-proxy signature scheme from bilinear pairings and proved its security in their security model. Although they proved that their scheme is secure under this model, we disprove their claim and show that their scheme is not secure. We also present a simple fix to prevent this attack. © 2011 Elsevier Ltd. All rights reserved.


Xiong H.,Peking University | Chen Z.,Peking University | Li F.,Chongqing Key Laboratory of Computer Network and Communication Technology
Security and Communication Networks | Year: 2012

In this paper, we introduce an efficient and trustworthy conditional privacy-preserving communication protocol for VANETs based on proxy re-signature. The proposed protocol is characterized by the trusted authority (TA) designating the roadside units to translate signatures computed by the on-board units into one that are valid with respect to TA's public key. In addition, the proposed protocol offers both a priori and a posteriori countermeasures: it can not only provide fast anonymous authentication and privacy tracking, but also guarantee message trustworthiness for vehicle-to-vehicle communications. Furthermore, it reduces the communication overhead and offers fast message authentication and low storage requirements. We use extensive analysis to demonstrate the merits of the proposed protocol and to contrast it with previously proposed solutions. © 2012 John Wiley & Sons, Ltd.


Xiong H.,University of Electronic Science and Technology of China | Xiong H.,Chongqing Key Laboratory of Computer Network and Communication Technology | Xiong H.,Fujian Normal University | Xiong H.,CAS Institute of Software | And 3 more authors.
Science China Information Sciences | Year: 2014

To enjoy the property of error tolerance in the biometric identities extraction, the fuzzy identitybased signature has been initialized to issue a signature on behalf of a descriptive attributes set ω instead of a single string. Any attributes set ω′ can be used to verify the validity of the signature in case the distance between ω and ω′ is less than a pre-defined threshold. Recently, Wang re-formalized the notion of fuzzy identitybased signature and proposed a concrete pairing-based construction along with the efficiency analysis and formal security proof. Unfortunately, by giving concrete attack, we indicate that Wang's scheme is not secure against forgery attack. We also present an improved scheme to prevent this attack. © 2014 Science China Press and Springer-Verlag Berlin Heidelberg.


Huang Y.,University of Electronic Science and Technology of China | Huang Y.,Chongqing Key Laboratory of Computer Network and Communication Technology | Huang Y.,Chongqing University of Posts and Telecommunications | Xie M.,University of Electronic Science and Technology of China | And 2 more authors.
Proceedings - 2011 8th International Conference on Fuzzy Systems and Knowledge Discovery, FSKD 2011 | Year: 2011

Fractional differential is used to adjust the affinity matrix of the image and to extract more useful edge and texture information. A graph is constructed for the original image with edge and texture information calculated with fractional differential, and the Laplacian matrix is obtained and the eigenvector corresponding to the second eigenvalue is classified to get the final segmentation results. Experimental results show that the proposed method can extract more fine details, preserve more useful information and get more accurate results. © 2011 IEEE.


Huang Y.,University of Electronic Science and Technology of China | Huang Y.,Chongqing Key Laboratory of Computer Network and Communication Technology | Huang Y.,Chongqing University of Posts and Telecommunications | Xie M.,University of Electronic Science and Technology of China | And 3 more authors.
Journal of Information and Computational Science | Year: 2012

Algebraic Multi-grid (AMG) method is analyzed and is combined with the graph cut method to extract the texture feature of the image. AMG method can extract more information about the singularities in the image. The data in the coarse grid is utilized to reconstruct the image and the reconstruct result approximates to the original image well. On the basis of the analysis on the AMG method, an energy function is constructed for the texture feature and minimized using max-flow method. Experimental results show that the proposed method can extract more texture details accurately. © 2012 by Binary Information Press.


Ma B.,Chongqing University | Ma B.,Chongqing Key Laboratory of Computer Network and Communication Technology | Xie X.,Chongqing University | Xie X.,Chongqing Key Laboratory of Computer Network and Communication Technology
Communications in Computer and Information Science | Year: 2011

In this study, we address the spectrum handover mechanism for proactive-decision in cognitive radio networks. Spectrum handover occurs when the primary users suddenly appear and the secondary users are using the particular primary user's licensed channel. The proactive-sensing spectrum handover which the target channel is pre-determined. And handover avoid the sensing time, but the pre-determined target channel may not be available. So we develop a spectrum handover mechanism by using an efficient channel-scheduling algorithm to reduce disabled channel. Its basic idea is in that a new packet is scheduled by migrating some packets to other channels if none of any idle channels can accommodate it; otherwise repeating the other migrate or stay channel processes. © 2011 Springer-Verlag Berlin Heidelberg.


Chen J.,University of Electronic Science and Technology of China | Li J.,University of Electronic Science and Technology of China | Li J.,Chongqing Key Laboratory of Computer Network and Communication Technology | Lin J.,University of Electronic Science and Technology of China | Huang Y.,Chengdu University of Information Technology
2014 11th International Computer Conference on Wavelet Active Media Technology and Information Processing, ICCWAMTIP 2014 | Year: 2014

In this paper, we utilize negacyclic codes to construct a family of optimal subsystem codes with parameters [[q2+1,(q-1)2, 4, q-1]]q, where q ≡ 1(mod4), q = pτ, τ ≥ 1 and p is an odd prime. These constructed quantum subsystem codes are different from those codes available in the literature. © 2014 IEEE.


Tang X.,University of Science and Technology of China | Tao Z.,University of Science and Technology of China | Tang P.,University of Science and Technology of China | Li J.,University of Science and Technology of China | Li J.,Chongqing Key Laboratory of Computer Network and Communication Technology
2014 11th International Computer Conference on Wavelet Active Media Technology and Information Processing, ICCWAMTIP 2014 | Year: 2014

Pulse-Coupled Neural Network is known as third generation artificial neural network. It is created by visual cortex neurons, a synchronous pulse release phenomenon of mammals. Compare to traditional artificial neural network, PCNN has the characteristics of dynamic neural network, integrated space-time, automatic propagation and synchronous pulse release. PCNN has tendency for image retention information and edge detection. © 2014 IEEE.


Tang P.-S.,University of Electronic Science and Technology of China | Tang X.-L.,University of Electronic Science and Technology of China | Tao Z.-Y.,University of Electronic Science and Technology of China | Li J.-P.,University of Electronic Science and Technology of China | Li J.-P.,Chongqing Key Laboratory of Computer Network and Communication Technology
2014 11th International Computer Conference on Wavelet Active Media Technology and Information Processing, ICCWAMTIP 2014 | Year: 2014

The wide application of Internet technology and media technology produces more and more data which also leads the arrival of the era of big data. However, it is difficult to extract the needed information from the original data directly except some special conditions. In recent years, the development of machine learning which provide a effective way to solve this problem for us. You can obtain lower rate of Miscalculate when you select a reasonable feature selection algorithm under the premise of not increasing the complexity of algorithm. At present it is divided into two categories named the Filter and Wrapper feature selection algorithm in the field of machine learning. This paper considers both the advantages and disadvantages of these two feature selection algorithm and studies the combined feature selection algorithm. © 2014 IEEE.


Zhu G.,University of Electronic Science and Technology of China | Xiong H.,Chongqing Key Laboratory of Computer Network and Communication Technology | Qin Z.,University of Electronic Science and Technology of China
Wireless Personal Communications | Year: 2014

To achieve unforgeability and confidentiality simultaneously, signcryption has been introduced with better efficiency than the signature-then-encryption approach in terms of computational costs and communication overheads. Taking the key leakage into account, it is desirable to design identity-based key-insulated signcryption (ID-KI-SC) scheme to reduce the damage caused by the secret key leakage. In this paper, we have shown that all of the existing ID-KI-SC scheme can not offer either the unforgeability property or the indistinguishability property. Furthermore, an improved scheme along with the formal security proof in the standard model has been suggested in this paper. In view of computational cost and communication overhead, our scheme is amongst the most efficient IB-SC schemes secure in the standard model. © 2014, Springer Science+Business Media New York.

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