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    25 March 2014, Volume 35 Issue 3
    Self-adapted task allocation algorithm with complicated coalition in wireless sensor network
    2014, 35(3):  1-10. 
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    Considering the real-time requirement and some specific limitations (e.g. insufficient computing resource, energy constraint, etc) in task scheduling of wireless sensor networks, different priorities were assigned to tasks according to their deadline, and an adaptive task allocation algorithm with complicated coalition was designed through analyzing historical information. Moreover, a discrete particle swarm optimization algorithm was designed via employing binary matrix coding form. The proposed optimization algorithm generates coalitions in parallel and then performs subtask allocation algorithm based on load and energy balance. Finally, the experimental results show that the proposed algorithm strikes a good balance between local solution and global exploration, and achieves a satisfactory result within a short period of time.
    Academic paper
    Self-adapted task allocation algorithm with complicated coalition in wireless sensor network
    Wen-zhong GUO,Jin-shu SU,Cheng-yu CHEN,Guo-long CHEN
    2014, 35(3):  1-10.  doi:10.3969/j.issn.1000-436x.2014.03.001
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    Considering the real-time requirement and some specific limitations (e.g.insufficient computing resource,energy constraint,etc) in task scheduling of wireless sensor networks,different priorities were assigned to tasks according to their deadline,and an adaptive task allocation algorithm with complicated coalition was designed through analyzing historical information.Moreover,a discrete particle swarm optimization algorithm was designed via employing binary matrix coding form.The proposed optimization algorithm generates coalitions in parallel and then performs subtask allocation algorithm based on load and energy balance.Finally,the experimental results show that the proposed algorithm strikes a good balance between local solution and global exploration,and achieves a satisfactory result within a short period of time.

    Complex network clustering algorithm based on Jordan-form of Laplace-matrix
    2014, 35(3):  2-21. 
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    Among existing clustering algorithms, the graph-Laplacian-based spectrum clustering algorithm has rigorous theoretical basis and high accuracy. However, the application of this algorithm is limited by its dependence on the prior knowledge, such as the number and the size of clusters. Based on the Jordan form of graph Laplacian, an algorithm was proposed which can obtain the prior knowledge, and perform the primary clustering based on the eigenvalues of the Jordan form. The modularity density function of clusters was defined, and an improved spectrum clustering algorithm with the help of the function and the primary clustering was proposed. The experiments were conducted on diverse datasets showing that, compared with the classic algorithms such as Fast-Newman and Girvan-Newman, the algorithm can reach a high clustering accuracy and a fast convergence rate.
    Queue stability distributed spectrum access algorithm based on Markov model for cognitive radio network
    2014, 35(3):  3-29. 
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    The queue stability of the secondary users in cognitive network was considered. A Markov chain model for the state of users in the cognitive network was constructed and a distributed CSMA algorithm was proposed. The secondary users adjust the parameters of back-off time due to the arrival and service rate to ensure the queue stability. Upper bound of the capacity of secondary users under the collision constrainting to primary user was derived in closed form. If the arrival rate of secondary users is smaller than the upper bound of capacity, queue stability can be ensured by the proposed algorithm. Simulations verified the effectiveness of the algorithm.
    Two-way relaying protocol tailored for sensor network
    2014, 35(3):  4-37. 
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    A three-time-slot two-way relaying protocol, named as two-way selective decode-and-forward (TW-SDF) protocol, was proposed. This relaying protocol integrates network coding and the selective decode-and-forward method, and was tailored for wireless networks with simple devices, like sensor networks. Compared with the well-known physical-layer network coding protocol, the considered TW-SDF has the merits of full diversity order gain, low encoding and decoding complexity and easy-to-implement. Provided block codes, an upper bound on the block error rate of TW-SDF was derived and proved, which is valid for all hard decoders. Simulation results further verify that the upper bound is remarkably tight if BCH codes are utilized.
    Geometrical statistical channel model with an Inverted-Parabolic spatial distribution
    2014, 35(3):  5-46. 
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    Due to the complexity of calculation for the parameters of angle of arrival(AOA), time of arrival(TOA) and Doppler spectra(DS),etc., a proper geometrical statistical channel model was proposed with inverted-parabolic spatial distribution around mobile station(MS) by using geometric partitioning method. Closed-form expressions for probability density functions(PDF) of AOA ,TOA and DS in the outdoor macrocell and microcell wireless environments were derived. Compared with the uniform and Gaussian scatter density model, the observed results consist with previous theory and experience. In addition, the Doppler spectra at the MS was also presented and the Clarke U-shaped model was modified. Employing the channel model, the effect of directional antenna was analyzed with the main-lobe width 2α at the BS and D/R and .
    Research on trustworthiness measurement approaches of component based BPRAS
    2014, 35(3):  6-57. 
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    Aiming at the absence of measurement methods about formalization on trustworthiness attributes of business process reengineering oriented application server (BPRAS), a cooperation framework of business process modeling and trustworthiness measurement based on BPRAS was proposed. Extracting the features of characteristics and behaviors of components consisting of the application server, an abstraction view of computing between those components based on the framework was presented through process algebraic approaches. Furthermore, relative concepts about its components computing operators were defined in order to construct algebraic model of its software trustworthiness (ST) to support the measurement of trustworthy BPRAS. Finally, an application case was also given.
    Spectrum sharing schemes in cognitive radio networks based on collusion formation
    2014, 35(3):  7-68. 
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    When multiple primary network (PN) with different interests competes to offer spectrum access opportunities for a single secondary network, a spectrum sharing scheme based on a repeated game model could be adopted to form a colluded monopoly for the licensed spectrum so as to maximize their total transmission utility. However, when a does not value its future transmission utility enough, it might choose to deviate from the present colluded monopoly to obtain a transmission utility larger than its monopoly utility, which then reduces the current and future transmission utilities of all other PN. Two new strategies were thereby proposed to produce a more flexible and credible spectrum sharing monopoly among all PN. Numerical simulation shows that, compared with the existing triggering strategy, the proposed strategies can effectively increase the overall transmission utility of all PN.
    Differentiated services dynamic spectrum access strategy for cognitive wireless mesh network
    2014, 35(3):  8-76. 
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    Dynamic spectrum access (DSA) is an important design aspect for cognitive radio network. Common access of multi-type services having different quality of service (QoS) requirements is the important characteristic of cognitive wireless mesh network. Differentiated service (DS) is the key to realize the high efficiency use of spectrum resources and to guarantee the high quality transmission of services. In order to satisfy the demand for multi-type services, a differentiated services dynamic spectrum access strategy was proposed. In this strategy, the unlicensed user traffic was divided into three priority classes. The DSA scheme uses different access mechanisms for the three classes of unlicensed users. The real-time traffic selectes available channel set according to the shortest expected delay to reduce the transmission time and the probability of appearance of licensed user during data transmission process. The general traffic selectes the channel of largest successful transmission probability to avoid spectrum handoff. The theoretical and experimental results show that, when compared with the traditional cognitive networks DSA strategy, the proposed strategy is able to guarantee different QoS for the various services, shorter transmission delay for higher priority services, reducing the probability of transmission interruption and better throughput performance when the vacancy rate of licensed channel is major and heavy network load.
    Semi-random and semi-algebraic structural design for IRA-LDPC codes
    2014, 35(3):  9-84. 
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    A method of semi-random and semi-algebraic structure was presented for constructing the low-density parity-check matrix that corresponds to the information bits of the IRA codes. Compared with the existing structural LDPC codes, the distinct advantage of the presented compact structural array for information-bit-corresponding matrix is that the position coordinate of each 1 element in this matrix can be calculated by a determinate algebraic expression, which not only reduces the consumption of memory resource for the random parity-check matrix, but also provides the potential probability for designing low complexity hardware circuit of the LDPC encoder/decoder. In addition, compared with the existing practical LDPC codes in industrial standard, the presented IRA-LDPC code is also slight preponderance in the performance of simulation in bit error rate and signal noise ratio (BER-SNB).
    Priority-based message forwarding and query processing in opportunistic wireless sensor network
    2014, 35(3):  10-93. 
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    A priority-based algorithm called PBQ was proposed for the query forwarding and processing in opportunistic wireless sensor network. Through the user-defined query priorities, the proposed algorithm properly selects the relay nodes and controlls the forwarding and the amount of messages. Meanwhile, the query priorities were adjusted dynamically so that the query results could be forwarded back to the source node of the query quickly and the residual query request messages could be cleaned up from the network, saving lots of unnecessary transmissions and improving the overall utility of query processing. Simulating results show that PBQ could effectively improve the success rate of queries, and reduce the cost and delay of query processing in opportunistic wireless sensor network.
    Cooperative spectrum sensing scheme based on crowd trust and decision-making mechanism
    2014, 35(3):  11-108. 
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    A distributed consensus-based scheme by simulating the crowd trust and decision-making mechanism was proposed. This scheme firstly predicts the dynamic trust value among sensing users by the previous cooperative process, and then generates the user's relative trust value, and makes the data interaction among the users by using the combination of relative trust value and decision-making mechanism. All users' state can reach a consensus as the credible and iterative data interaction. All users get the final results by the determinant algorithm. This new spectrum sensing scheme utilizes the imbalance of each users' sensing ability in the real environment. Each secondary user can maintain cooperation with others only through the local information exchange with the neighbors. It is quite different from traditional spectrum sensing scheme, such as OR-rule, 1-out-of-N rule and ordinary iterative method. Three SSDF attacks were analysed, on the basis of the corresponding anti-attack policy was proposed. Theoretical analysis and simulation results show that the new scheme is better than the existing cooperative spectrum sensing algorithm in accuracy and security. New scheme not only can improve the accuracy of spectrum sensing but also has the strong anti-attack capability.
    Academic paper
    Complex network clustering algorithm based on Jordan-form of Laplace-matrix
    Jian-wei NIU,Bin DAI,Chao TONG,Guan-ying HUO,Jing PENG
    2014, 35(3):  11-21.  doi:10.3969/j.issn.1000-436x.2014.03.002
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    Among existing clustering algorithms,the graph-Laplacian-based spectrum clustering algorithm has rigorous theoretical basis and high accuracy.However,the application of this algorithm is limited by its dependence on the prior knowledge,such as the number and the size of clusters.Based on the Jordan form of graph Laplacian,an algorithm was proposed which can obtain the prior knowledge,and perform the primary clustering based on the eigenvalues of the Jordan form.The modularity density function of clusters was defined,and an improved spectrum clustering algorithm with the help of the function and the primary clustering was proposed.The experiments were conducted on diverse datasets showing that,compared with the classic algorithms such as Fast-Newman and Girvan-Newman,the algorithm can reach a high clustering accuracy and a fast convergence rate.

    Secure fault-tolerant code for cloud storage
    2014, 35(3):  12-115. 
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    A secure regenerating code, called SRCS was proposed to solve the security problem during the process of the fault-tolerant of storage systems, especially the storage system in an extremely open environment such as cloud computing and cloud storage. SRCS achieves the security of the encoding matrix in the regenerating code using the threshold public-key encryption with low redundancy and high efficiency. It is proven that SRCS is secure in the semi-adaptive model using decisional BDHE assumption.
    Modified link prediction algorithm based on AdaBoost
    2014, 35(3):  13-123. 
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    The mainstream of current link prediction algorithm based on network topology structure generally have the problem of low efficiency of recalls. Study found that the correct results from some of the link prediction algorithms are complementary, accordingly, the Boosting method was considered to improve it. According to whether there is a link relationship between the nodes, the problem was divided into two categories, thus the link prediction algorithm as a two classification problem was defined. Furthermore, the algorithm complementary principle to select a number of representative link prediction algorithms as weak classifiers was followed, and a novel link prediction algorithm based on the AdaBoost algorithm was come up. The experimental results on the data from real dataset like the arXiv paper cooperation network and E-mail network show that, the novel algorithm has a better accuracy than the current mainstream algorithms.
    Dynamic accumulators-based authenticated group key management scheme for heterogeneous wireless sensor network
    2014, 35(3):  14-134. 
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    Witnesses of a dynamic accumulator (DA) can ensure whether an object has been accumulated. On the basis of this, node membership in a cluster was verified and a novel authenticated group key management protocol was proposed, which supports node revocation and addition. In order to establish a group key for a cluster, each member provides their assigned number to join accumulation. DAAG can not only guarantee the confidentiality of witnesses, but also keep non-members from calculating novel group keys by binding witness with group key update. The security and performance analyses show that DAAG is resistant against replay attack, forgery attack and collusion attack, and can provide forward security and backward security.
    The 2-adic complexity and the 1-error 2-adic complexity of single cycle T-functions
    2014, 35(3):  15-139. 
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    The 2-adic complexities of the coordinate sequences derived from single cycle T-functions over were investigated. Let be an integer such that . It is shown that the 2-adic complexity of the th coordinate sequence is upper bounded by . The distribution of the corresponding 2-adic number associated with the th coordinate sequence of all single cycle T-functions was also discussed, which implies that the upper bound is attainable. Moreover, 1-error 2-adic complexity was also studied. It was proved that the 1-error 2-adic complexity of the th coordinate sequence is equal to its 2-adic complexity except for .
    Fair multi-party concurrent signature scheme
    2014, 35(3):  16-149. 
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    Multi-party concurrent signatures were first proposed by Tonien et al at ISC2006, but Xie and Tan pointed Tonien et al’s scheme doesn’t satisfy fairness and they reconstructed multi-party concurrent signature schemes respectively. Through analysis, the multi-party concurrent signature schemes proposed by Xie and Tan don’t satisfy fairness either, so a formal security model of fair multi-party concurrent signatures was proposed and a multi-party concurrent signature scheme based on bilinear pairing and multi-party key agreement was also reconstructed. Analysis shows that the new scheme satisfies correctness, unforgeability, ambiguity, concurrency and fairness in the random oracle model assuming the CDH problem is intractable and highly efficient in signature size, computation cost and communication cost compared with other schemes of its kind.
    Multi-dimension resource allocation algorithm based on QoS guarantee in dense WLAN
    2014, 35(3):  17-156. 
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    A multi-dimension radio resource allocation method was proposed to improve the network performance in dense WLAN. By joint evaluation of the network covering, interference between cells and user’s QoS satisfaction, the object function of the radio resource allocation was founded and tabu search method was used to find the optimum solution of the object function. The optimum solution is the resource allocation vector including the best AP set, AP’s channel set and power set. The simulation results show that the proposed method improves the network performance and provides a better guarantee of user’s QoS requirement.
    Research of power preprocessing optimization-based template attack on LED
    2014, 35(3):  18-167. 
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    The security of LED, a lightweight block cipher proposed in CHES 2011, was evaluated by the template attack (TA). Several improvements of TA from the perspective of the preprocessing optimization was proposed. Firstly, the noise offset was calculated by using the phase-only correlation factor in the frequency view of the power trace to eliminate the data interference in the template building phase. Secondly, a novel character extracting method was proposed based on calculating the cross-cluster offset of different clusters classified by the plaintexts to cut the different leakage points from the power traces automatically. Thirdly, a dynamic effective power points choosing strategy was proposed by utilizing the mean value and the noises of the of power traces to evaluate the differences between different templates and improve the utilization of side channel information. Experiment results demonstrate that the proposed techniques of data alignment and automatically data cutting enlarge the differences of templates and reduce the number of the required power trace in both the template building and attacking phase. The proposed effective power points choosing strategy reduces the data complexity of the attack and only two power traces are required to launch the attack with the success rate of 100%.
    Improved cooperative spectrum sensing scheme based on dempster-shafer theory in cognitive radio network
    2014, 35(3):  19-173. 
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    An improved cooperative spectrum sensing scheme based on dempster-shafer evidence theory in cognitive radio networks was proposed. In the local sensing period, the projection approximation algorithm was introduced to reduce bandwidth for cooperation. In the fusion period, credibility was calculated by the distance between evidence vectors of different secondary users and adopted as the weights to combine different local sensing data. The new scheme reduces channel bandwidth and simulation results show that the new scheme improves the performance under the condition of high level conflict.
    Priority-based routing and wavelength assignment algorithm of multi-objective in WDM network
    2014, 35(3):  20-182. 
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    An effective algorithm aiming at the multi-objective routing and wavelength assignment through priority in dynamic WDM optical network was proposed. The objective of the design is to maximize the number of accepted communication requests subjected to a limited number of wavelength channels. The relation between path type was adopted and the traffic volume was used to determine the priority of the connection requests, and the network state was incorporated into the routing decisions and wavelength assignment. The simulation results conclusively demonstrate that the proposed algorithm can greatly improve the blocking performance and utilization of the optical network resource.
    Fundamental performance limits of CPM coded modulation system
    2014, 35(3):  21-192. 
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    The study of the capacity of CPM systems was concerned with. The definition as well as the Finite-State-Machine (FSM) model of CPM was introduced. The development of calculating the capacity of CPM over AWGN channels was first reviewed. Then this methodology was generalized to deal with Rayleigh fading channels. The Monte-Carlo based algorithms were derived to calculate the capacity of CPM over Rayleigh fading channels with and without knowing channel-state-information(CSI). The proposed algorithms were justified by some numerical results of some typical CPM schemes.
    New solution scheme for the member revocation in group signature
    2014, 35(3):  22-200. 
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    In order to solve the problem that Camenisch-Stadler’s group signature scheme could not revoke members, a new revocation scheme based on the Camenisch-Stadler’s group scheme was proposed, allowing the group manager to add new members or revoke old members flexibly and freely. When a member joins the group, the group manager issues member certificate to him (her), and other members need not update the key and certificate; when a member is revoked, the group manager only adds the anonymous identity to revocation list, and other members need not update the key and certificate either. Furthermore, the length of the signature and the computational effort are independent of the number of the group members and the revoked members, so the new scheme is more suitable for large group and the group with members’ heavy updates.
    Academic paper
    Queue stability distributed spectrum access algorithm based on Markov model for cognitive radio network
    Xiao-hui LI,Jin-zhao ZHANG,Yong-qiang HEI
    2014, 35(3):  22-29.  doi:10.3969/j.issn.1000-436x.2014.03.003
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    The queue stability of the secondary users in cognitive network was considered.A Markov chain model for the state of users in the cognitive network was constructed and a distributed CSMA algorithm was proposed.The secondary users adjust the parameters of back-off time due to the arrival and service rate to ensure the queue stability.Upper bound of the capacity of secondary users under the collision constrainting to primary user was derived in closed form.If the arrival rate of secondary users is smaller than the upper bound of capacity,queue stability can be ensured by the proposed algorithm.Simulations verified the effectiveness of the algorithm.

    Research on simple query algorithm during mobile terminal disconnection
    2014, 35(3):  23-207. 
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    A simple query processing algorithm SQPID (simple query processing in disconnection), was proposed. Main idea of SQPID is to build integrated related semantic cache item about current query through combining and clipping operations. In order to simplify the procedure, SQPID’s combine does not involve indirect relativity estimation. The results of simulated experiments show that SQPID’s query response time and degree of accuracy better meet client’s requirements than QPID algorithm.
    Nonlinear scale-space based boundary localization for nonideal iris
    2014, 35(3):  24-215. 
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    A nonlinear scale-space based localization method of nonideal iris boundaries was proposed. The method eliminates small-scaled geometric structures while preserving large-scaled iris boundaries by nonlinear diffusions with the scale-evolution property. Moreover it combines such diffusions with the frame of multiresolution analysis, and achieves fast and effective iris boundary detection. Experimental results indicate that compared with the classical methods, the proposed algorithm extract nonideal iris boundaries accurately and efficiently with overcoming the disadvantageous influences of the nonideal factors.
    Image encryption algorithms based on chaos through dual scrambling of pixel position and bit
    2014, 35(3):  25-222. 
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    As the current popular chaos-based image encryption algorithms with the permutation–diffusion structure have security flaws of no immunity to attack. A new image encryption algorithm was proposed based on the analysis of current algorithms, which can well resist the chosen-plaintext and the chosen-ciphertext attacks. The algorithm uses Kent chaotic map to generate key streams, and produces the parameters of the chaotic system and the iteration times according to the characteristics of plaintext pixels and input key. Firstly, the positions of pixels were shuffled totally with the chaotic se-quence. Secondly, the 0 and 1 bit positions of image pixels were scrambled by using another chaotic sequence generated by the input key. The experimental results show that the algorithm cannot only resist the chosen plaintext attack and chosen ciphertext attack but also achieve better cryptographic properties,such as key space, statistical analysis.
    Pulse state-interval modulation and experiment in the hostile environments
    2014, 35(3):  26-230. 
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    Based on the Shannon classical communication theory, the atmospheric modulation model of wireless laser communication was investigated for enhancing wireless laser communication adaptability of the atmospheric channel. Firstly, the conversion relations of SER and BER was discussed, from error theory perspectives analysis atmospheric optical wireless communications. Afterwards,by analyzing Shannon limit communication rate of wireless laser communication in atmospheric channel, the importance of atmospheric channel bandwidth gradually came out. On the basis of this, an efficiency pulse state-interval coded modulation was present and its characteristics were estimated. Finally, the feasibility of the PSIM and the importance of atmospheric channel bandwidth to wireless laser communication were proved by wireless laser communication experiment in the hostile environments, At the end, a prospect was pointed out that atmospheric channel properties feedback technique in real time might be a key and precondition in all-weather wireless optical communication.
    Apply PSO into cloud storage task scheduling with QoS preference awareness
    2014, 35(3):  27-238. 
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    The task scheduling algorithm in cloud storage area with QoS preference awareness was studied. Firstly, the differences between cloud storage and cloud computing were pointed, and exist matrix was used to avoid the creation of useless solutions. Secondly, QoS factors were summarized into three classes: time, cost and quality classes. Based on the three classes, the fitness function of the PSO was improved by using weighted factors to adjust the QoS preference. The simulation results release that PSO is not fit for the overall scheduling when the task distributions of different degrees are unevenness because the QoS demand of wide distribution tasks may cover the QoS demand of other tasks. So a hierarchical scheduling based on degree is necessary. The simulation results show that the improved hierarchical PSO scheduling algorithm can aware the QoS preference relevantly.
    Academic paper
    Two-way relaying protocol tailored for sensor network
    Qing-feng ZHOU,Zhi-zhong DING,Cai-hong KAI
    2014, 35(3):  30-37.  doi:10.3969/j.issn.1000-436x.2014.03.004
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    A three-time-slot two-way relaying protocol,named as two-way selective decode-and-forward (TW-SDF) protocol,was proposed.This relaying protocol integrates network coding and the selective decode-and-forward method,and was tailored for wireless networks with simple devices,like sensor networks.Compared with the well-known physical-layer network coding protocol,the considered TW-SDF has the merits of full diversity order gain,low encoding and decoding complexity and easy-to-implement.Provided block codes,an upper bound on the block error rate of TW-SDF was derived and proved,which is valid for all hard decoders.Simulation results further verify that the upper bound is remarkably tight if BCH codes are utilized.

    Geometrical statistical channel model with an Inverted-Parabolic spatial distribution
    Jie ZHOU,Dong-dong XU,Kikuchi HISAKAZU
    2014, 35(3):  38-46.  doi:10.3969/j.issn.1000-436x.2014.03.005
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    Due to the complexity of calculation for the parameters of angle of arrival(AOA),time of arrival(TOA) and Dopplerspectra(DS),etc.,a proper geometrical statistical channel model was proposed with inverted-parabolic spatial distribution around mobile station(MS) by using geometric partitioning method.Closed-form expressions for probability density functions(PDF) of AOA ,TOA and DS in the outdoor macrocell and microcell wireless environments were derived.Compared with the uniform and Gaussian scatter density model,the observed results consist with previous theory and experience.In addition,the Doppler spectra at the MS was also presented and the Clarke U-shaped model was modified.Employing the channel model,the effect of directional antenna was analyzed with the main-lobe width 2α at the BS and D/R and φ .v

    Research on trustworthiness measurement approaches of component based BPRAS
    Qiang HAN,Yu-yu YUAN
    2014, 35(3):  47-57.  doi:10.3969/j.issn.1000-436x.2014.03.006
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    Aiming at the absence of measurement methods about formalization on trustworthiness attributes of business process reengineering oriented application server (BPRAS),a cooperation framework of business process modeling and trustworthiness measurement based on BPRAS was proposed.Extracting the features of characteristics and behaviors of components consisting of the application server,an abstraction view of computing between those components based on the framework was presented through process algebraic approaches.Furthermore,relative concepts about its components computing operators were defined in order to construct algebraic model of its software trustworthiness (ST) to support the measurement of trustworthy BPRAS.Finally,an application case was also given.

    Spectrum sharing schemes in cognitive radio networks based on collusion formation
    Xue-song TAN,Chao LIN,Wei GUO
    2014, 35(3):  58-58.  doi:10.3969/j.issn.1000-436x.2014.03.007
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    When multiple primary network (PN) with different interests competes to offer spectrum access opportunities for a single secondary network,a spectrum sharing scheme based on a repeated game model could be adopted to form a colluded monopoly for the licensed spectrum so as to maximize their total transmission utility.However,when a does not value its future transmission utility enough,it might choose to deviate from the present colluded monopoly to obtain a transmission utility larger than its monopoly utility,which then reduces the current and future transmission utilities of all other PN.Two new strategies were thereby proposed to produce a more flexible and credible spectrum sharing monopoly among all PN.Numerical simulation shows that,compared with the existing triggering strategy,the proposed strategies can effectively increase the overall transmission utility of all PN.

    Differentiated services dynamic spectrum access strategy for cognitive wireless mesh network
    Rui-fang LI,Quan LIU,Ren-fa LI
    2014, 35(3):  69-76.  doi:10.3969/j.issn.1000-436x.2014.03.008
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    Dynamic spectrum access (DSA) is an important design aspect for cognitive radio network.Common access of multi-type services having different quality of service (QoS) requirements is the important characteristic of cognitive wireless mesh network.Differentiated service (DS) is the key to realize the high efficiency use of spectrum resources and to guarantee the high quality transmission of services.In order to satisfy the demand for multi-type services,a differentiated services dynamic spectrum access strategy was proposed.In this strategy,the unlicensed user traffic was divided into three priority classes.The DSA scheme uses different access mechanisms for the three classes of unlicensed users.The real-time traffic selectes available channel set according to the shortest expected delay to reduce the transmission time and the probability of appearance of licensed user during data transmission process.The general traffic selectes the channel of largest successful transmission probability to avoid spectrum handoff.The theoretical and experimental results show that,when compared with the traditional cognitive networks DSA strategy,the proposed strategy is able to guarantee different QoS for the various services,shorter transmission delay for higher priority services,reducing the probability of transmission interruption and better throughput performance when the vacancy rate of licensed channel is major and heavy network load.

    Semi-random and semi-algebraic structural design for IRA-LDPC codes
    Li PENG,Qi ZHANG,Bo WANG,Tao CHEN
    2014, 35(3):  77-84.  doi:10.3969/j.issn.1000-436x.2014.03.009
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    A method of semi-random and semi-algebraic structure was presented for constructing the low-density parity-check matrix that corresponds to the information bits of the IRA codes.Compared with the existing structural LDPC codes,the distinct advantage of the presented compact structural array for information-bit-corresponding matrix is that the position coordinate of each 1 element in this matrix can be calculated by a determinate algebraic expression,which not only reduces the consumption of memory resource for the random parity-check matrix,but also provides the potential probability for designing low complexity hardware circuit of the LDPC encoder/decoder.In addition,compared with the existing practical LDPC codes in industrial standard,the presented IRA-LDPC code is also slight preponderance in the performance of simulation in bit error rate and signal noise ratio (BER-SNB).

    Priority-based message forwarding and query processing in opportunistic wireless sensor network
    Yong-xuan LAI,Zi-yu LIN
    2014, 35(3):  85-93.  doi:10.3969/j.issn.1000-436x.2014.03.010
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    A priority-based algorithm called PBQ was proposed for the query forwarding and processing in opportunistic wireless sensor network.Through the user-defined query priorities,the proposed algorithm properly selects the relay nodes and controlls the forwarding and the amount of messages.Meanwhile,the query priorities were adjusted dynamically so that the query results could be forwarded back to the source node of the query quickly and the residual query request messages could be cleaned up from the network,saving lots of unnecessary transmissions and improving the overall utility of query processing.Simulating results show that PBQ could effectively improve the success rate of queries,and reduce the cost and delay of query processing in opportunistic wireless sensor network.

    Cooperative spectrum sensing scheme based on crowd trust and decision-making mechanism
    Xiao-mao WANG,Chuan-he HUANG,Yi-long LV,Bin WANG,Xi-ying FAN,Hao ZHOU
    2014, 35(3):  94-108.  doi:10.3969/j.issn.1000-436x.2014.03.011
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    A distributed consensus-based scheme by simulating the crowd trust and decision-making mechanism was proposed.This scheme firstly predicts the dynamic trust value among sensing users by the previous cooperative process,and then generates the user's relative trust value,and makes the data interaction among the users by using the combination of relative trust value and decision-making mechanism.All users' state can reach a consensus as the credible and iterative data interaction.All users get the final results by the determinant algorithm.This new spectrum sensing scheme utilizes the imbalance of each users' sensing ability in the real environment.Each secondary user can maintain cooperation with others only through the local information exchange with the neighbors.It is quite different from traditional spectrum sensing scheme,such as OR-rule,1-out-of-N rule and ordinary iterative method.Three SSDF attacks were analysed,on the basis of the corresponding anti-attack policy was proposed.Theoretical analysis and simulation results show that the new scheme is better than the existing cooperative spectrum sensing algorithm in accuracy and security.New scheme not only can improve the accuracy of spectrum sensing but also has the strong anti-attack capability.

    Secure fault-tolerant code for cloud storage
    Peng-xu TAN,Yue CHEN,Ju-long LAN,Hong-yong JIA
    2014, 35(3):  109-115.  doi:10.3969/j.issn.1000-436x.2014.03.012
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    A secure regenerating code,called SRCS was proposed to solve the security problem during the process of the fault-tolerant of storage systems,especially the storage system in an extremely open environment such as cloud computing and cloud storage.SRCS achieves the security of the encoding matrix in the regenerating code using the threshold public-key encryption with low redundancy and high efficiency.It is proven that SRCS is secure in the semi-adaptive model using decisional BDHE assumption.

    Modified link prediction algorithm based on AdaBoost
    Zu-feng WU,Qi LIANG,Qiao LIU,Zhi-guang QIN
    2014, 35(3):  116-123.  doi:10.3969/j.issn.1000-436x.2014.03.013
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    The mainstream of current link prediction algorithm based on network topology structure generally have the problem of low efficiency of recalls.Study found that the correct results from some of the link prediction algorithms are complementary,accordingly,the Boosting method was considered to improve it.According to whether there is a link relationship between the nodes,the problem was divided into two categories,thus the link prediction algorithm as a two classification problem was defined.Furthermore,the algorithm complementary principle to select a number of representative link prediction algorithms as weak classifiers was followed,and a novel link prediction algorithm based on the AdaBoost algorithm was come up.The experimental results on the data from real dataset like the arXiv paper cooperation network and E-mail network show that,the novel algorithm has a better accuracy than the current mainstream algorithms.

    Dynamic accumulators-based authenticated group key management scheme for heterogeneous wireless sensor network
    Xiao-rui ZHONG,Chun-guang MA
    2014, 35(3):  124-134.  doi:10.3969/j.issn.1000-436x.2014.03.014
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    Witnesses of a dynamic accumulator (DA) can ensure whether an object has been accumulated.On the basis of this,node membership in a cluster was verified and a novel authenticated group key management protocol was proposed,which supports node revocation and addition.In order to establish a group key for a cluster,each member provides their assigned number to join accumulation.DAAG can not only guarantee the confidentiality of witnesses,but also keep non-members from calculating novel group keys by binding witness with group key update.The security and performance analyses show that DAAG is resistant against replay attack,forgery attack and collusion attack,and can provide forward security and backward security.

    The 2-adic complexity and the 1-error 2-adic complexity of single cycle T-functions
    Wei YOU,Wen-feng QI
    2014, 35(3):  135-139.  doi:10.3969/j.issn.1000-436x.2014.03.015
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    The 2-adic complexities of the coordinate sequences derived from single cycle T-functions over F 2n were investigated.Let j be an integer such that 0≤ j≤n?1.It is shown that the 2-adic complexity of the j th coordinate sequence is upper bounded by lb(22j+1).The distribution of the corresponding 2-adic number associated with the j th coordinate sequence of all single cycle T-functions was also discussed,which implies that the upper bound is attainable.Moreover,1-error 2-adic complexity was also studied.It was proved that the 1-error 2-adic complexity of the j th coordinate sequence is equal to its 2-adic complexity except for j=0.

    Fair multi-party concurrent signature scheme
    Qing YE,Yun YANG,Shi-hui ZHENG,Li-wei CHANG,Da XIAO,Yi-xian YANG
    2014, 35(3):  140-149.  doi:10.3969/j.issn.1000-436x.2014.03.016
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    Multi-party concurrent signatures were first proposed by Tonien et al at ISC2006,but Xie and Tan pointed Tonien et al's scheme doesn't satisfy fairness and they reconstructed multi-party concurrent signature schemes respectively.Through analysis,the multi-party concurrent signature schemes proposed by Xie and Tan don't satisfy fairness either,so a formal security model of fair multi-party concurrent signatures was proposed and a multi-party concurrent signature scheme based on bilinear pairing and multi-party key agreement was also reconstructed.Analysis shows that the new scheme satisfies correctness,unforgeability,ambiguity,concurrency and fairness in the random oracle model assuming the CDH problem is intractable and highly efficient in signature size,computation cost and communication cost compared with other schemes of its kind.

    Multi-dimension resource allocation algorithm based on QoS guarantee in dense WLAN
    Qi ZHANG,Lin-jing ZHAO,Jian-dong LI
    2014, 35(3):  150-156.  doi:10.3969/j.issn.1000-436x.2014.03.017
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    A multi-dimension radio resource allocation method was proposed to improve the network performance in dense WLAN.By joint evaluation of the network covering,interference between cells and user's QoS satisfaction,the object function of the radio resource allocation was founded and tabu search method was used to find the optimum solution of the object function.The optimum solution is the resource allocation vector including the best AP set,AP's channel set and power set.The simulation results show that the proposed method improves the network performance and provides a better guarantee of user's QoS requirement.

    Research of power preprocessing optimization-based template attack on LED
    Xiao-juan WANG,Shi-ze GUO,Xin-jie ZHAO,Mei SONG,Fan ZHANG
    2014, 35(3):  157-167.  doi:10.3969/j.issn.1000-436x.2014.03.018
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    The security of LED,a lightweight block cipher proposed in CHES 2011,was evaluated by the template attack (TA).Several improvements of TA from the perspective of the preprocessing optimization was proposed.Firstly,the noise offset was calculated by using the phase-only correlation factor in the frequency view of the power trace to eliminate the data interference in the template building phase.Secondly,a novel character extracting method was proposed based on calculating the cross-cluster offset of different clusters classified by the plaintexts to cut the different leakage points from the power traces automatically.Thirdly,a dynamic effective power points choosing strategy was proposed by utilizing the mean value and the noises of the of power traces to evaluate the differences between different templates and improve the utilization of side channel information.Experiment results demonstrate that the proposed techniques of data alignment and automatically data cutting enlarge the differences of templates and reduce the number of the required power trace in both the template building and attacking phase.The proposed effective power points choosing strategy reduces the data complexity of the attack and only two power traces are required to launch the attack with the success rate of 100%.

    Improved cooperative spectrum sensing scheme based on dempster-shafer theory in cognitive radio network
    Mei-ting YU,Lin-jing ZHAO,Zhao LI
    2014, 35(3):  168-173.  doi:10.3969/j.issn.1000-436x.2014.03.019
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    An improved cooperative spectrum sensing scheme based on dempster-shafer evidence theory in cognitive radio networks was proposed.In the local sensing period,the projection approximation algorithm was introduced to reduce bandwidth for cooperation.In the fusion period,credibility was calculated by the distance between evidence vectors of different secondary users and adopted as the weights to combine different local sensing data.The new scheme reduces channel bandwidth and simulation results show that the new scheme improves the performance under the condition of high level conflict.

    Priority-based routing and wavelength assignment algorithm of multi-objective in WDM network
    Xiang-xuan TIAN,Jun-gang YANG,Ya-liang CHE,Wen-zheng SUN,Gu-jing LIU
    2014, 35(3):  174-182.  doi:10.3969/j.issn.1000-436x.2014.03.020
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    An effective algorithm aiming at the multi-objective routing and wavelength assignment through priority in dynamic WDM optical network was proposed.The objective of the design is to maximize the number of accepted communication requests subjected to a limited number of wavelength channels.The relation between path type was adopted and the traffic volume was used to determine the priority of the connection requests,and the network state was incorporated into the routing decisions and wavelength assignment.The simulation results conclusively demonstrate that the proposed algorithm can greatly improve the blocking performance and utilization of the optical network resource.

    Overview
    Fundamental performance limits of CPM coded modulation system
    Bing LI,Fan WEI,Bao-ming BAI,Xiao MA
    2014, 35(3):  183-192.  doi:10.3969/j.issn.1000-436x.2014.03.021
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    The study of the capacity of CPM systems was concerned with.The definition as well as the Finite-State-Machine (FSM) model of CPM was introduced.The development of calculating the capacity of CPM over AWGN channels was first reviewed.Then this methodology was generalized to deal with Rayleigh fading channels.The Monte-Carlo based algorithms were derived to calculate the capacity of CPM over Rayleigh fading channels with and without knowing channel-state-information(CSI).The proposed algorithms were justified by some numerical results of some typical CPM schemes.

    Academic communication
    New solution scheme for the member revocation in group signature
    De-dong ZHANG,Zhao-feng MA,Yi-xian YANG,Xin-xin NIU
    2014, 35(3):  193-200.  doi:10.3969/j.issn.1000-436x.2014.03.022
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    In order to solve the problem that Camenisch-Stadler's group signature scheme could not revoke members,a new revocation scheme based on the Camenisch-Stadler's group scheme was proposed,allowing the group manager to add new members or revoke old members flexibly and freely.When a member joins the group,the group manager issues member certificate to him (her),and other members need not update the key and certificate; when a member is revoked,the group manager only adds the anonymous identity to revocation list,and other members need not update the key and certificate either.Furthermore,the length of the signature and the computational effort are independent of the number of the group members and the revoked members,so the new scheme is more suitable for large group and the group with members' heavy updates.

    Research on simple query algorithm during mobile terminal disconnection
    Ru-bing LIANG,Qiong LIU
    2014, 35(3):  201-207.  doi:10.3969/j.issn.1000-436x.2014.03.023
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    A simple query processing algorithm SQPID (simple query processing in disconnection),was proposed.Main idea of SQPID is to build integrated related semantic cache item about current query through combining and clipping operations.In order to simplify the procedure,SQPID's combine does not involve indirect relativity estimation.The results of simulated experiments show that SQPID's query response time and degree of accuracy better meet client's requirements than QPID algorithm.

    Nonlinear scale-space based boundary localization for nonideal iris
    Hong-lin WAN,Bao-sheng LI,Min HAN,Deng-wang LI
    2014, 35(3):  208-215.  doi:10.3969/j.issn.1000-436x.2014.03.024
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    A nonlinear scale-space based localization method of nonideal iris boundaries was proposed.The method eliminates small-scaled geometric structures while preserving large-scaled iris boundaries by nonlinear diffusions with the scale-evolution property.Moreover it combines such diffusions with the frame of multiresolution analysis,and achieves fast and effective iris boundary detection.Experimental results indicate that compared with the classical methods,the proposed algorithm extract nonideal iris boundaries accurately and efficiently with overcoming the disadvantageous influences of the nonideal factors.

    Image encryption algorithms based on chaos through dual scrambling of pixel position and bit
    Xiao-heng DENG,Chun-long LIAO,Cong-xu ZHU,Zhi-gang CHEN
    2014, 35(3):  216-223.  doi:10.3969/j.issn.1000-436x.2014.03.025
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    As the current popular chaos-based image encryption algorithms with the permutation–diffusion structure have security flaws of no immunity to attack.A new image encryption algorithm was proposed based on the analysis of current algorithms,which can well resist the chosen-plaintext and the chosen-ciphertext attacks.The algorithm uses Kent chaotic map to generate key streams,and produces the parameters of the chaotic system and the iteration times according to the characteristics of plaintext pixels and input key.Firstly,the positions of pixels were shuffled totally with the chaotic sequence.Secondly,the 0 and 1 bit positions of image pixels were scrambled by using another chaotic sequence generated by the input key.The experimental results show that the algorithm cannot only resist the chosen plaintext attack and chosen ciphertext attack but also achieve better cryptographic properties,such as key space,statistical analysis.

    Pulse state-interval modulation and experiment in the hostile environments
    Yi-ning MU,He WANG,Ping LI,Hui-lin JIANG
    2014, 35(3):  224-230.  doi:10.3969/j.issn.1000-436x.2014.03.026
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    Based on the Shannon classical communication theory,the atmospheric modulation model of wireless laser communication was investigated for enhancing wireless laser communication adaptability of the atmospheric channel.Firstly,the conversion relations of SER and BER was discussed,from error theory perspectives analysis atmospheric optical wireless communications.Afterwards,by analyzing Shannon limit communication rate of wireless laser communication in atmospheric channel,the importance of atmospheric channel bandwidth gradually came out.On the basis of this,an efficiency pulse state-interval coded modulation was present and its characteristics were estimated.Finally,the feasibility of the PSIM and the importance of atmospheric channel bandwidth to wireless laser communication were proved by wireless laser communication experiment in the hostile environments,At the end,a prospect was pointed out that atmospheric channel properties feedback technique in real time might be a key and precondition in all-weather wireless optical communication.

    Apply PSO into cloud storage task scheduling with QoS preference awareness
    Juan WANG,Fei LI,Lu-qiao ZHANG
    2014, 35(3):  231-238.  doi:10.3969/j.issn.1000-436x.2014.03.027
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    The task scheduling algorithm in cloud storage area with QoS preference awareness was studied.Firstly,the differences between cloud storage and cloud computing were pointed,and exist matrix was used to avoid the creation of useless solutions.Secondly,QoS factors were summarized into three classes:time,cost and quality classes.Based on the three classes,the fitness function of the PSO was improved by using weighted factors to adjust the QoS preference.The simulation results release that PSO is not fit for the overall scheduling when the task distributions of different degrees are unevenness because the QoS demand of wide distribution tasks may cover the QoS demand of other tasks.So a hierarchical scheduling based on degree is necessary.The simulation results show that the improved hierarchical PSO scheduling algorithm can aware the QoS preference relevantly.

Copyright Information
Authorized by: China Association for Science and Technology
Sponsored by: China Institute of Communications
Editor-in-Chief: Zhang Ping
Associate Editor-in-Chief:
Zhang Yanchuan, Ma Jianfeng, Yang Zhen, Shen Lianfeng, Tao Xiaofeng, Liu Hualu
Editorial Director: Wu Nada, Zhao Li
Address: F2, Beiyang Chenguang Building, Shunbatiao No.1 Courtyard, Fengtai District, Beijing, China
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Tel: 010-53933889、53878169、
53859522、010-53878236
Email: xuebao@ptpress.com.cn
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ISSN 1000-436X
CN 11-2102/TN
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