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Table of Content

    01 September 2012, Volume 32 Issue 09
    Network and communications
    Review of coverage and handoff technologies of 3G communication for high-speed railway
    Xin-Hua JIANG ZHU QUAN
    2012, 32(09):  2385-2390.  DOI: 10.3724/SP.J.1087.2012.02385
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    This paper focused on the environmental characteristics of High-Speed Railway (HSR) and its influence on 3rd Generation (3G) mobile communication networks. Firstly, the technical characteristics of three major 3G communication standards in China were analyzed, especially the two key issues in the construction of HSR communication system: wireless coverage and fast handoff. Then the body loss of serials of HSR, the minimum switching area and the optimization deployment strategies of 3G communication technologies in China were summarized. Lastly, the tendency of HSR's wireless communication technologies was prospected and it was found that the Long Term Evolution (LTE) technologies could provide the technical feasibility for the broadband application services of HSR. Hence, it is suggested that we should strengthen the research for wireless transmission performance optimization of TD-LTE in HSR environment.
    Encryption-based indirect incentive mechanism in BitTorrent
    ZHANG Hong-mei QI Fa-zhi MAN Jin-gui WANG Miao
    2012, 32(09):  2391-2394.  DOI: 10.3724/SP.J.1087.2012.02391
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    In order to deal with exploiting in BitTorrent system,a fluid model was proposed to evaluate the effect of exploiting in BitTorrent system.With this model,the exploiting tolerance threshold can be obtained.When the ratio of exploiters exceeds this threshold,the system may die.To avoid the system dying,an Encryption-based Indirect Incentive Mechanism (EIIM) was proposed,in which a downloader must seed for a while before it can obtain the key to decrypt the file received.Also EIIM can give more download bandwidth to those nodes that provide more upload bandwidth to others.The simulation results show that BitTorrent system without EIIM cannot restrain exploiting.With EIIM,the seeders in BitTorrent system can get 2-3 times download efficiency than those without EIIM.
    Enhanced minimalist mutual-authentication protocol for RFID system
    ZHANG Xue-jun CAI Wen-qi WANG Yu
    2012, 32(09):  2395-2399.  DOI: 10.3724/SP.J.1087.2012.02395
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    Concerning the disadvantage of the Minimalist Mutual-Authentication Protocol (M2AP) that it cannot resist the man-in-the-middle attacks,an Enhanced M2AP (EM2AP) was presented by protecting the messages transmitted between reader and tag. The protocol calculated the Hamming weight of the shared key of tag and reader and then used the weight value to protect the transmitted message on the cyclic shift,thus effectively avoiding the man-in-the-middle attacks. By BAN logic, security analysis and performance analysis,this paper shows that this protocol cannot only maintain the low cost of tags,but also ensure good security and reliability.
    Topology-transparent MAC scheduling code for mobile Ad Hoc network supporting multi-class services
    LI Xi-yang FAN Ping-zhi
    2012, 32(09):  2400-2404.  DOI: 10.3724/SP.J.1087.2012.02400
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    A construction of topology-transparent Media Access Control (MAC) scheduling code for mobile Ad Hoc network supporting multi-class services was proposed.The code length was minimized under the condition that one successful transmission slot was guaranteed for each user in lowest priority class.The proposed code has much flexibility in choosing the transmission slots and its construction is simple.The performance analysis shows that the wireless network employing the proposed MAC scheduling code can support users with multi-class services and provide them guaranteed Quality of Service (QoS).
    Analysis of communication signals based on physical-layer network coding
    LIU Qin-yong PENG Hua
    2012, 32(09):  2405-2407.  DOI: 10.3724/SP.J.1087.2012.02405
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    The Physical-layer Network Coding (PNC) is difficult to be wiretapped. In order to wiretap and recover the signals from the PNC system, a blind signal processing algorithm based on decoding was proposed to recover the information sequences from the senders in the paper. Firstly, the algorithm analyzed the mapping signal from the second slot in PNC scheme in order to get the parameters of modulation and encoding. Secondly, the algorithm processed the mixed signal from the first slot in the PNC scheme, and clustered the sampling data to judge the component of bit information. At last, the paper used the decoding algorithm to correct the information and took the mixed signal apart successfully. Extensive simulation studies show that the new algorithm based on constellation analysis and decoding can recover the signals blindly, and the Bit Error Rate (BER) reaches 10-3 when the Signal-to-Noise Ratio (SNR) is 11 dB.
    Parameters adjustment in cognition radio spectrum allocation based on game theory
    ZHANG Bei-wei HU Kun-yuan ZHU Yun-long
    2012, 32(09):  2408-2411.  DOI: 10.3724/SP.J.1087.2012.02408
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    With regard to the dynamic spectrum allocation on wireless cognitive network, a dynamic Bertrand game algorithm of the channel pricing of licensed users was proposed using Bertrand equilibrium. Then, the relationship between stability of Nash equilibrium and speed parameter adjustment was analyzed. Consequently, step response function was utilized to replace the non-concussive process of game, and three-value method was proposed for getting step response parameters. The simulation results show that the proposed algorithm can obtain stable channel price when the value of speed parameter is less than 0. 04. Besides, the feasibility of using a step function to analyze the concussion game process is proved, and this method is convenient for licensed users to make real-time price and bring more economic benefits.
    Optimal linear cooperation spectrum sensing method based on chaos harmony search algorithm
    LI Yue-hong WAN Pin WANG Yong-hua YANG Jian DENG Qin
    2012, 32(09):  2412-2417.  DOI: 10.3724/SP.J.1087.2012.02412
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    In order to improve the accuracy and reliability of cognitive radio spectrum sensing, an optimal linear cooperation spectrum sensing method based on Chaos Harmony Search (CHS) algorithm was proposed in this paper. This algorithm is based on the linear weighted cooperative spectrum sensing model with energy detection, using the optimization capability of Harmony Search (HS) and the traverse and randomness of chaotic system to find the optimal weight values and then improve the performances of spectrum sensing for cognitive radio networks. The simulation results show that the proposed algorithm has better optimal performance and convergence speed than the traditional HS algorithm. This CHS algorithm can obtain optimal weight values and improve the probability of detection in complex communications environment. Besides, cooperation spectrum sensing performance based on the proposed algorithm is better than the existing Modified Deflection Coefficient (MDC) method with the same false probability.
    Directed diffusion gradient field based on double gradient in vehicular sensor networks
    ZHENG Ming-cai LI Yong-fan ZHAO Xiao-chao LI Ke-feng
    2012, 32(09):  2418-2421.  DOI: 10.3724/SP.J.1087.2012.02418
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    In order to speed up forming Directed Diffusion (DD) gradient field and improve the connectivity of logic networks, a Directed Diffusion Gradient Field based on Double Gradient (DDGF-DG) for Vehicular Sensor Networks (VSN) was proposed. With the help of the estimated gradient value of roadside-node, the large scale vehicular sensor network was divided into a certain number of sub-reigns taking roadside-nodes as the local cores, the local directed diffusion gradient field around every roadside-node was set up in distributed way, and at last, the global directed diffusion gradient field composed of the local directed diffusion gradient fields was formed with the help of double gradient value, so the autonomous management in every sub-reign was realized. Theoretical analysis and simulation results show that DDGF-DG and its dynamic adjustment would reduce the time consumption and improve the real-time connectivity.
    Routing algorithm based on link bandwidth utilization rate
    YANG Xiao-qin ZHANG Li-fang CAO Qing-huang SUN Hai-yan LI Zhuo-qing
    2012, 32(09):  2422-2425.  DOI: 10.3724/SP.J.1087.2012.02422
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    In order to avoid network congestion, concerning that the current algorithms have not considered the aspects of network flow distribution and user's perception, a routing algorithm which can realize maximum load balance was proposed. The algorithm can decrease the maximal bandwidth utilization rate of network with delay guaranteed. The experiment based on real Abilene2 network topology shows that the proposed algorithm can alleviate the network congestion and improve the network utilization rate over 50% effectively. Compared with the existing algorithms, the proposed algorithm can meet two requirements of the bandwidth utilization and network delay. In addition, by adjusting the parameter values it can meet different business requirements in actual networks.
    Location algorithm based on BP neural network in OFDM system
    MAO Yong-yi LI Cheng ZHANG Hong-jun
    2012, 32(09):  2426-2428.  DOI: 10.3724/SP.J.1087.2012.02426
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    For the purpose of reducing multi-path interference for positioning accuracy in Orthogonal Frequency Division Multiplexing (OFDM) systems, a location algorithm based on Back Propagation (BP) neural networks was proposed. MUltiple SIgnal Classification (MUSIC) algorithm was used to estimate the Time Of Arrival (TOA) of the first arrival path and calculate the Time Difference Of Arrival (TDOA). Then BP neural network was used to correct the TDOA. Finally Chan algorithm was used to determine the location of the mobile station. The location algorithm was simulated in multi-path environment. The simulation results show that this algorithm can effectively reduce the effect of the multi-path interference and the performance is better than Least Square (LS) algorithm, Chan algorithm and Taylor algorithm.
    Performance analysis of new centroid localization algorithm in wireless sensor network
    ZHANG Ai-qing YE Xin-rong HU Hai-feng
    2012, 32(09):  2429-2431.  DOI: 10.3724/SP.J.1087.2012.02429
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    Centroid Localization (CL) algorithm is a representative range-free localization algorithm in Wireless Sensor Network (WSN). To improve the localization accuracy of CL when anchors are unevenly distributed, Smallest Enclosing Polygon Localization (SEPL) algorithm was presented. In SEPL, the centroid of the smallest polygon which enclosed the neighbor anchors of the unknown node was regarded as the estimated location of the unknown node. The simulation results show that SEPL is robust when the topology of anchors is not uniform. The proposed algorithm outperforms CL by an average of 15% in localization accuracy.
    General method to estimate mixture matrix in blind source separation
    ZHANG Yan-liang ZHANG Wei-tao DU Jing-jing
    2012, 32(09):  2432-2435.  DOI: 10.3724/SP.J.1087.2012.02432
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    The estimation of mixture matrix is a key step to solve the problem of blind source separation. But there lacks a general estimation method suitable for well-determined, over-determined and under-determined mixture matrix in the existing research. Scaling and permutation ambiguities lie in both factor matrix of tensor canonical decomposition and mixture matrix in blind source separation. With this property, the estimation of mixture matrix can be transformed into tensor canonical decomposition of observed signals' statistics. The canonical decomposition can be implemented by cyclic minimization, with the algorithm of alternating least squares. The theoretical analysis and simulations show that the method proposed in this paper is a general method to estimate well-determined, over-determined and under-determined mixture matrix.
    Performance analysis of outage probability and diversity-multiplexing tradeoff for two-path relaying cooperative communications
    ZHAO Yong-chi,LIU Jing-xia,LI En-yu
    2012, 32(09):  2436-2440.  DOI: 10.3724/SP.J.1087.2012.02436
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    In order to improve the spectral efficiency and outage performance of the cooperative communication system, a Two-Path Relaying (TPR) cooperative communications model based on the Decode-and-Forward (DF) protocol was proposed. Meanwhile, two data transmission modes were presented for the proposed system. The closed-form expressions for outage probability and the relations between diversity gain and multiplexing gain were derived. The simulation results show that, compared with the conventional two-relay DF protocol, the outage probability performance of the two proposed transmission models is greatly improved.
    Multi-view video transmission method based on depth-map and distributed video coding
    WU Lin,JIN Zhi-gang,ZHAO An-an,ZHOU Yuan
    2012, 32(09):  2441-2444.  DOI: 10.3724/SP.J.1087.2012.02441
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    Concerning the large volume of data of multi-view video transmission system, an Unequal Error Protection (UEP) method based on depth-map and Distributed Video Coding (DVC) was proposed. Firstly, the depth-map based on multi-view was extracted. Secondly, one point view and the depth-map were transmitted. Finally, through the network transmission, other point views were generated by the point view and the depth-map at the decoder. Considering their different importance at the decoder, different distributed video coding methods were used in the point view and the depth-map to realize UEP. The simulation results show that the proposed transmission method provides stronger error resilience and higher transmission reliability, and it improves the Peak Signal-to-Noise Ratio (PSNR) of images about 1. 5 dB than traditional distributed multi-view video coding transmission system.
    Wavelet threshold algorithm analysis under non-Gaussian noise background
    LI Qing-hua Senbai Dalabaev QIU Xin-jian LIAO Chang SUN Quan-fu
    2012, 32(09):  2445-2447.  DOI: 10.3724/SP.J.1087.2012.02445
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    A new threshold function under non-Gaussian noise background was presented to overcome the limitations of wavelet threshold algorithm under the Gaussian noise background. The shortcomings of conventional function, such as discontinuity of hard threshold function and the invariable dispersion of soft threshold function, can be solved. The new function which employed high order power function was put forward based on Garrote threshold. First, the signal with a class of non-Gaussian noise was decomposed by wavelet. Secondly, each high frequency wavelet coefficient was quantified based on new threshold function. Thirdly, signal was reconstructed by the low frequency coefficients of wavelet decomposition and quantified high frequency coefficients. The simulation results under non-Gaussian noise background indicate that the new threshold function gets higher Signal-to-Noise Ratio (SNR) gains and lower minimum Mean Square Error (MSE) compared to the soft and hard threshold, two types of improved threshold and Garrote threshold.
    Network and distributed techno
    Load balancing strategy of cloud computing based on adaptive artificial bee colony algorithm
    YAO Jing HE Ju-hou
    2012, 32(09):  2448-2450. 
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    When Artificial Bee Colony (ABC) algorithm is applied to the load balancing system, local intensive resources may arise due to improper handling of the relationship between requests. Therefore, an improved adaptive ABC algorithm was proposed. By introducing other types of requests, the request accumulation of the similar type got blocked. Then, not only the availability but also the system throughput had been improved. The experimental results show that either the system throughput or the scalability of the load balancing mechanism based on ABC algorithm, is applicable to cloud computing environments. The improved adaptive ABC algorithm is superior to traditional algorithms more than 5% in system throughput.
    Hybrid tabu search for scheduling reentrant jobs on parallel machines
    ZHAO Yue HU Yu-mei
    2012, 32(09):  2451-2454.  DOI: 10.3724/SP.J.1087.2012.02451
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    A hybrid tabu search algorithm was proposed in this paper for the reentrant scheduling problem on parallel machines with a remote service equipment. Concerning that only one start-point was used in the traditional tabu search algorithm which made it trapped in local optimum easily, a Restart method was established in the hybrid tabu search algorithm. When the traditional tabu search algorithm was trapped in local optimum, the Restart method was used to rebuild the initial solution and preceded with the tabu search algorithm. Thus, the traditional single start-point search was changed into multiple start-points search. Comparisons were made between the hybrid tabu search algorithm and a Coordinate Scheduling (CS) algorithm. The computational experiments show the effectiveness of the hybrid tabu search algorithm, whose optimization performance is superior to the CS algorithm. Moreover, the computation time is acceptable.
    Bit-split parallel algorithm for quick sorting based on Java
    TUO Qing SONG Yao-hu
    2012, 32(09):  2455-2457.  DOI: 10.3724/SP.J.1087.2012.02455
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    This paper presented a new sorting algorithm based on bit-split quick sort that aimed to explore the algorithm which had excellent performance for large data. The algorithm split data in bit, and parallel processed the split data in combination with Java's concurrent mechanism. The data experiments show that the new sorting algorithm is significantly better than quick sort for large data sorting and owns very good parallel efficiency.
    Parallel algorithms for complex network clustering with GPUs
    WANG Hai-feng
    2012, 32(09):  2458-2462.  DOI: 10.3724/SP.J.1087.2012.02458
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    The complex network clustering algorithm to research the topology properties of complex network needs to deal with large-scale nodes and links. Therefore, it requires higher computation performance to the large-scale complex networks that represent the complex system in reality. Hence, a parallel complex network clustering algorithm on Graphic Processing Units (GPU) based on fast Newman clustering algorithm was designed through the primitive technology that not only reduced the complexity of the parallel algorithm design but also improved the universality in various applications. Then from the thread scheduling strategies and the cache management perspectives, the optimal parallel complex network clustering algorithms were presented to deal with the load balance and the data reuse problem in computing process. The experiments results of the parallel complex network clustering algorithm and the optimal algorithms show that the optimal algorithms have better performance than the former.
    Parallelization of decision tree algorithm based on MapReduce
    LU Qiu CHENG Xiao-hui
    2012, 32(09):  2463-2465.  DOI: 10.3724/SP.J.1087.2012.02463
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    In view of that the traditional decision tree algorithm that cannot solve the mass data mining and the multi-value bias problem of ID3 algorithm, the paper designed and realized a parallel decision tree classification algorithm based on the MapReduce framework. This algorithm adopted attribute similarity as the choice standard to avoid the multi-value bias problem of ID3 algorithm, and used the MapReduce model to solve the mass data mining problems. According to the experiments on the Hadoop cluster set up by ordinary PCs, the decision tree algorithm based on MapReduce can deal with massive data classification. What's more, the algorithm has good expansibility while ensuring the classification accuracy and can get close to linear speedup rate.
    Parallel simulation and optimization of CUDA-based real-time huge crowd behavior
    HE Yi-hui,YE Chen,LIU Zhi-zhong,PENG Wei
    2012, 32(09):  2466-2469.  DOI: 10.3724/SP.J.1087.2012.02466
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    That the individuals search relevant objects from the environment may cause high time complexity during the crowd simulation. If the crowd should be simulated in real-time, the time complexity of the model needs reducing and the computing capability of the simulation platform needs enhancing. In this paper, the Biods model was studied as a typical case and a solution of how to parallelize and optimize the real-time huge crowd simulation based on Compute Unified Device Architecture (CUDA) was presented. Each individual was correspondent to a logical Graphic Processing Unit (GPU) thread. By discretizing simulation environment, the efficiency of searching the relevant individuals was improved. The individual information was organized into an array with the spatial locality by parallel radix sort in order to improve the utilization of the GPU memory bandwidth. The experiment verifies the solution presented here has improved number of simulation individuals up to about 7.3 times as CPU solution.
    Modular multiplication algorithm with modulus expanded to maximum of integer
    SHAO Rong
    2012, 32(09):  2470-2471.  DOI: 10.3724/SP.J.1087.2012.02470
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    The modular multiplication with the modulus greater than the value of half bits of the integer would result in overflow, and the high precision arithmetic operations have to be used. To avoid the use of high precision arithmetic operations, a modular multiplication algorithm including reduction by congruence was proposed. By decomposing the operands to double-digit numbers and reducing the product of higher digit by congruence, operation overflow was avoided. The experimental results show that the modular multiplication based on 64 digit integers can use the modulus of up to 62 digit.
    Database technology
    Comprehensive method of computing ontology similarity based on association rules
    LI Hua SU Le
    2012, 32(09):  2472-2475.  DOI: 10.3724/SP.J.1087.2012.02472
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    The recent Risk Minimization based Ontology Mapping (RiMOM), based on multi-strategy, in spite of certain improvements, has the shortcomings in complexity and redundancy, and limitations in similarity selection of structure characteristics. Therefore, a comprehensive method of computing ontology similarity based on association rules was proposed. First, the "tree" model of association rules was constructed to compute the structure similarity. Then the similarity of instances, properties, and names were also computed. Finally, a comprehensive method was used to achieve the optimal calculation of the ontology similarity. The experimental results show that this method has higher recall and precision ratio and less time complexity than RiMOM.
    Improved GK clustering algorithm
    ZHANG Fang-fang QIAN Xue-zhong
    2012, 32(09):  2476-2479.  DOI: 10.3724/SP.J.1087.2012.02476
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    Traditional GK clustering algorithm cannot automatically determine the number of clusters, and is sensitive to the initial cluster centers. According to these defects, an improved algorithm was proposed in this paper. Firstly, a new validity index, based on the weighted sum of separation between clusters and inter-cluster compactness, was proposed for the determination of the proper number of clusters. Then the idea of an improved entropy clustering was referenced to determine the initial cluster centers. Finally, the improved algorithm clustered the data sets according to the number of clusters given by the new index and the new cluster centers. The experimental results show that the new index works well in situations when there are overlapping clusters in the data set, and the improved algorithm has a higher clustering accuracy.
    Web resource recommendation method based on intuitive fuzzy clustering
    XIAO Man-sheng WANG Xin-fang ZHOU Li-juan
    2012, 32(09):  2480-2482.  DOI: 10.3724/SP.J.1087.2012.02480
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    In the classification of the Web resources, a recommending method of Web resources based on intuitive fuzzy C-means clustering was proposed to solve the problem that the traditional method based on user interest cannot reflect the change of their interests accurately and the difficulty in distinguishing the quality and the style of content of resources. In the method, firstly, the Web resources were expressed as intuitive fuzzy data according to the user interest degree. Then the integrated theory of intuitive fuzzy information was applied to classify the resources. Lastly, the similar resources would be recommended to user successfully. Theoretical analysis and experimental results show that this method has a great advantage in improving the quality of recommendation compared with traditional fuzzy C-means and collaborative filtering method.
    Descriptive query method based on unstructured text data in GIS
    PU Hai-xia LI Jia-tian LI Rui HE Yu-feng WANG Hua
    2012, 32(09):  2483-2487.  DOI: 10.3724/SP.J.1087.2012.02483
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    Since the traditional Geographic Information System (GIS)'s structured or semi-structured attribute query poses sort of limitation on input accuracy and scope of query sentences, a GIS descriptive query method for text-related non-structured text data was suggested based on the expanded version of a dictionary of English synonyms, TongYiCi CiLin. compiled by Harbin Institute of Technology. Basic process is to calculate correlation between descriptive query sentence and text connected to the geographic element, then getting general query results according to it. The comparison experiment shows that descriptive query method not only supports diversity of input query sentence, but also effectively gets geographic element related to input descriptive query.
    Name disambiguation based on query expansion
    YANG Xin-xin LI Pei-feng ZHU Qiao-ming
    2012, 32(09):  2488-2490.  DOI: 10.3724/SP.J.1087.2012.02488
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    Taking into account that many existing name disambiguation approaches are not suitable for documents with few features, this paper put forward a method that can get more features related to documents through search engine extension with the help of rich Internet resources. Firstly, four types of queries were constructed according to the characteristics of the search engine rules, and then search was done based on those query rules and the first k documents were returned. Lastly, a feature selection method of Document Frequency (DF) was used in these documents and the selected features were added to the original documents. The experimental results show that the query expansion approach can improve the performance of name disambiguation and make F-measure increase from 76% to 81%.
    Extraction of text content from PDF documents based on automaton theory
    WANG Xiao-juan TAN Jian-long LIU Yan-bing LIU Jin-gang
    2012, 32(09):  2491-2495.  DOI: 10.3724/SP.J.1087.2012.02491
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    The existing methods of extracting text content from a PDF file, such as the one adopted by the PDFBox library, are not efficient enough to handle the high-speed network traffic. Moreover, these methods cannot extract the contents streamingly from partial PDF packets in transfer. This paper proposed a new method based on automaton theory. The method adopted a hierarchical keyword Deterministic Finite Automaton (DFA) to extract information from complete or incomplete PDF files. The experimental results show that the response time of the proposed method is about 17% - 37% of the algorithm used by PDFBox when processing PDF files in Chinese or English.
    Data storage method supporting large-scale smart grid
    SONG Bao-yan ZHANG Hong-mei WANG Yan LI Qiong
    2012, 32(09):  2496-2499.  DOI: 10.3724/SP.J.1087.2012.02496
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    Concerning that the monitoring data in large-scale smart grid are massive, real-time and dynamic, a new data storage approach supporting large-scale smart grid based on data-centric was proposed, which is a hierarchical extension scheme for storing massive dynamic data. Firstly, the extended Hash coding method could adjust the number of storage nodes dynamically to avoid data loss of sudden or frequent events and increase system availability. Then, the multi-threshold leveling method was used to distribute data to multiple storage nodes, which could avoid hotspot storage problem and achieve load balance. Simulation results show that this method is able to satisfy the need of massive data storage, to obtain better load balance, to lower the total energy consumption and to extend the life cycle of the whole network.
    Fast recovery method of effective data based on FAT32
    YANG De-ming
    2012, 32(09):  2500-2503.  DOI: 10.3724/SP.J.1087.2012.02500
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    For the objective device failure and subjective data destruction, this paper raised a fast data recovery solution. In case that the file system was not corrupt or not damaged severely, the available worthy content in the File Allocation Table (FAT) could be selected and used for fast data recovery. If the file system was damaged severely (or the computer evidence taking needs), the entire space of the physical hard disk (including invisible region in the operation system) could be checked and the maximum of valid user data could be extracted. According to the data storage and deletion mechanism in the FAT32 file system, by scanning the unallocated space in FAT, a method was provided to restore the deleted file based on the cluster number of sector storing file header signature and the file size in the directory entry. The compound document structure was explored, and a method to extract useful information was provided according to the specification of document storage and the identity of the data stream. The experiments show that the scheme can simply and efficiently recover the deleted data.
    Artificial intelligence
    Finite Newton algorithm for Lagrangian support vector regression
    ZHENG Feng-de ZHANG Hong-bin
    2012, 32(09):  2504-2507.  DOI: 10.3724/SP.J.1087.2012.02504
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    Lagrangian Support Vector Regression (SVR) is an effective algorithm and its solution is obtained by taking the inverse of a matrix of order equaling the number of samples plus one, but needs many times to terminate from a starting point. This paper proposed a finite Armijo-Newton algorithm solving the Lagrangian SVR's optimization problem. A solution was obtained by solving a system of linear equations at a finite number of times rather than solving a quadratic programming problem. The proposed method has the advantage that the result optimization problem is solved with global convergence and finite-step termination. The experimental results on several benchmark datasets indicate that the proposed algorithm is fast, and shows good generalization performance.
    Multiple time series autoregressive method based on support vector regression
    ZHANG Wei LIU Xian-hui DING Yi SHI De-ming
    2012, 32(09):  2508-2511.  DOI: 10.3724/SP.J.1087.2012.02508
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    Energy consumption time series involves a variety of energy and the relationship between different energy is complicated. Most existing consumption methods make prediction through multiple independent single time series respectively, which ignores dependencies between multiple time series. In order to take full advantage of the association between multiple time series and improve prediction accuracy, the vector-valued autoregressive method and multi-task autoregressive method based on Support Vector Regression (SVR) machines were proposed for multiple time series forecast according to vector-valued function learning and multi-task learning theory. The experimental results with energy consumption of coking process verify that multiple time series autoregressive models based on the proposed methods show better prediction performance.
    Signal sparse decomposition based on the two dictionary sets
    WANG Shu-peng WANG Wen-xiang LI Hong-wei
    2012, 32(09):  2512-2515.  DOI: 10.3724/SP.J.1087.2012.02512
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    A new sparse decomposition algorithm was presented to get a sparser representation of the signal. In the procedure of the algorithm, it established the two dictionary sets consisting of the selected dictionary set and the unselected dictionary set. The proposed algorithm added a more strict process which selected the best kernel from the unselected dictionary set to the original Repeated Weighted Boosting Search (RWBS), so the proposed algorithm could produce a sparser model while reserving the advantages of the original algorithm. The effectiveness of the proposed algorithm is illustrated through several examples.
    Evaluation model based on neighborhood preservation for manifold learning algorithms
    SHI Lu-kui,ZHANG Jun,GONG Xiao-teng
    2012, 32(09):  2516-2519.  DOI: 10.3724/SP.J.1087.2012.02516
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    The stress function and the residual variance are only fit to evaluate the manifold learning algorithms with strict distance preservation. And dy-dx representation is only a qualitative measure. Although the variance of distance ratios can compare and judge most of manifold learning algorithms, the geodesic distances need computing in the method which leads to high computational complexity. An evaluation model based neighborhood preservation was proposed. In the model, only k nearest neighbors needed determining and the preservation ratio of the neighborhood in the low dimensional space needed computing for each object. The geodesic distances did not need calculating in the method. The theoretical analysis shows that the computational complexity of the proposed model is great lower than that of the variance of distance ratios. The performance of the two models was compared on three data sets. Experiments demonstrate that the proposed model not only can judge results from the same method with different parameters, but also can compare results by different algorithms. And the evaluation performance of manifold learning algorithms of the model is superior to that of the variance of distance ratios.
    Neural network for control chart pattern recognition based on kernel principle component analysis
    HU Sheng LI Tai-fu WEI Zheng-yuan YAN Ke-sheng
    2012, 32(09):  2520-2522.  DOI: 10.3724/SP.J.1087.2012.02520
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    Considering the problem that the abnormal features have great similarity so that simple structure and high precision modeling cannot be achieved, a control chart pattern recognition method based on Kernel Principal Component Analysis (KPCA) and neural network was proposed. Firstly, the kernel method was used to translate the nonlinear feature into a higher dimensional linear feature space. Secondly this feature was projected to lower dimensional feature space. Finally the BP neural network classifier was introduced to identify the control chart pattern. This method was verified through stochastic simulation. The result demonstrates that the model can cluster each control chart pattern effectively and improve recognition accuracy.
    Linguistic truth-valued concept lattice based on graded linguistic values chain and its application
    YANG Li WANG Yu-hui XU Yang
    2012, 32(09):  2523-2526.  DOI: 10.3724/SP.J.1087.2012.02523
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    In order to provide a logical basis and mathematical model for directly processing natural language, the Lukasiewicz implication algebra based on the graded linguistic values chain and the linguistic truth-valued concept lattice were established. The natural language used to depict certain values in practical problems was analyzed and equivalently expressed as the graded linguistic values set, on which the definitions of partial order relations and binary operators were given. The bijective relation was established between the graded linguistic values chain and the natural language set, and the specific linguistic truth-valued concept lattice was constructed based on the linguistic truth-valued lattice implication algebra. And then, the linguistic truth-valued concept lattice was applied into the analytical system with natural language for vehicle transport safety performance, which verified the feasibility of the model to directly deal with the natural language and the readability of the structure graph.
    Indoor cleaning robot path planning based on distance feature vector matching and fuzzy control
    ZHANG Zhi-jie
    2012, 32(09):  2527-2529.  DOI: 10.3724/SP.J.1087.2012.02527
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    With regard to the inefficiency of random path planning method used by many indoor cleaning robots, a low-cost and efficient improvement method was proposed in this paper. The main idea was that the distance between the robot and its surrounding obstacles varied with the location of working robot. First, ultrasound distance measurement was used for obtaining the distances to form the feature vector which could identify different locations in work place. Then feature matching problem was solved by Earth Move's Distance (EMD), and the set of collision points was established. At last, fuzzy control theory was used for controlling rotation angle after collision to finish path planning procedure. As shown on the experiments, the proposed method can not only reserve the property of enjoyment and environment flexibility, but also promote the efficiency greatly.
    Application of improved ant colony algorithm to route planning of anti-ship missile
    GAO Man LIU Yi-an ZHANG Qiang
    2012, 32(09):  2530-2533.  DOI: 10.3724/SP.J.1087.2012.02530
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    Application of the basic ant colony algorithm for anti-ship missile path planning problem has such shortcomings as slow convergence speed, long computation time, and easily falling into local optimum. Concerning these shortcomings, roulette selection strategy, elite strategy and path optimization strategy were adopted on traditional ant colony algorithm to optimize it, and the optimization algorithm was applied in anti-ship missile route planning. At the same time, by means of limiting the feasible course of anti-ship missile, the maximum search range for route planning was reduced. Simulation results show that the anti-ship missile route planning based on improved ant colony algorithm not only shortens the optimal route length but also speeds up the convergence rate of the optimal route search process.
    Facility location in emergency relief with uncertain demand and logistics network
    TAO Sha HU Zhi-hua
    2012, 32(09):  2534-2537.  DOI: 10.3724/SP.J.1087.2012.02534
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    With regard to the uncertain demand and logistics network in emergency relief, the problem of locating emergency distribution centers was studied to cope with uncertain demand and logistics network. The stochastic programming models based on set covering model were built to minimize the cost. Two different approaches, expected-value model and stochastic simulation were employed to solve uncertainty of the model. By samples and simulation study, the optimal solution of locating emergency distribution centers was obtained. It is found that stochastic simulation is a superior approach compared with expected-value model.
    Artificial bee colony algorithm based on cloud mutation
    LIN Xiao-jun YE Dong-yi
    2012, 32(09):  2538-2541.  DOI: 10.3724/SP.J.1087.2012.02538
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    Traditional Artificial Bee Colony (ABC) algorithms suffer from the problem of slow convergence and easy stagnation in local optima. An improved ABC algorithm based on cloud model, was proposed to solve the problem. By calculating a candidate food source through the normal cloud particle operator and by reducing the radius of the local search space, the proposed algorithm can enhance the convergence speed and exploitation capability. In order to maintain diversity, a new selection strategy that makes the inferior individual have more chances to be selected was introduced. In addition, the best solution found over time was used to explore a new position in the algorithm. A number of experiments on composition functions show that the proposed algorithm has been improved in terms of convergence speed and solution quality, and is better than some recently proposed improved ABC algorithms.
    Speaker recognition method based on Mel frequency cepstrum coefficient and inverted Mel frequency cepstrum coefficient
    HU Feng-song ZHANG Xuan
    2012, 32(09):  2542-2544.  DOI: 10.3724/SP.J.1087.2012.02542
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    To improve the performance of speaker recognition system, a new method of feature extraction was proposed based on Mel Frequency Cepstrum Coefficient (MFCC) and Inverted MFCC (IMFCC). This method constructed a mixed feature by combining MFCC with IMFCC using Fisher criterion. The experimental results show that the mixed feature proposed in this paper has better recognition performance compared with MFCC not only in the pure voice database but also in the noisy environments.
    Temperature control approach in intelligent office environment
    WANG Hai-zhen LIAN Zuo-zheng TENG Yan-ping
    2012, 32(09):  2545-2547.  DOI: 10.3724/SP.J.1087.2012.02545
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    The parameters of inverter air-conditioner are fixed, which cannot adapt to changed intelligent office environment. This paper proposed a new air-conditioner control approach in order to improve the comfort of the ambient temperature. Multi-Agent technology was introduced, and input and output variables and their fuzzy sets were given, and then the fuzzy Q-learning algorithm introduced rewards was proposed, which was executed by reasoning Agent to learn manually adjusting the air-conditioner action, and modify the fuzzy rules, so the fuzzy rules were optimized. Finally the optimization fuzzy rules were applied to control ambient temperature. The experimental result shows that the response time and overshoot of the air-conditioner are less than the conventional fuzzy temperature control approach.
    Graphics and image technology
    Seamlessly terrain rendering method based on binary tree and GPU
    CAO Wei DUAN Guang-yao
    2012, 32(09):  2548-2552.  DOI: 10.3724/SP.J.1087.2012.02548
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    In this paper a Graphic Processing Unit (GPU)-based and seamless method for terrain rendering was proposed. The method utilized binary tree to construct the terrain Level Of Detail (LOD) which was represented by row-column templates. In this method, the elevation data was transformed to elevation-texture and then the elevation-texture was used to extract elevation for rendering by Vertex Texture Fetch (VTF). And the whole process was handled by GPU so that the data accessing efficiency was greatly improved. The force-split method in Real-time Optimally Adapting Meshes (ROAM) was used in this method which solved terrain cracks by limiting the level of adjacent terrain blocks. The TriangleStrip primitive was used for terrain rendering which avoided transferring the same vertices' coordinates of adjacent triangles to GPU. Finally the paper tested the efficiency of the new method by two terrain datasets, and compared the frame rates between Clipmap and the new method. The results show that the new proposed method solves the terrain crack effectively and fulfills the demand of interactive terrain rendering.
    Algorithm of biased skeleton trim based on intersecting cortical model
    ZHOU Li HE Lin-yuan SUN Yi BI Du-yan GAO Shan
    2012, 32(09):  2553-2555.  DOI: 10.3724/SP.J.1087.2012.02553
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    In order to solve the problem of geometric distortion and low efficiency in the process of biased skeleton trim, a new algorithm of biased skeleton trim based on intersecting cortical model was proposed. At first, according to inherent features of skeleton biased branch, definitions of endpoint and junction point were introduced and revised in the algorithm to accurately locate skeleton branch and biased branch. Then, with that information and the iteration number of intersecting cortical model, flameout condition of neurons spreading was set up. Finally, guided by that condition, the biased skeleton branch can be judged fast and trimmed accurately, with the aid of impulse dynamically generated by ignition neurons, which has biological nature of parallel transmission. Compared with conventional methods based on mathematical morphology, the experimental results show that the proposed algorithm has good performance in structural integrity of skeleton, as well as computation speed and anti-noise ability.
    Obstacle detection of indoor robots based on monocular vision
    HE Shao-jia LIU Zi-yang SHI Jian-qing
    2012, 32(09):  2556-2559.  DOI: 10.3724/SP.J.1087.2012.02556
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    In this paper, a new monocular vision system was proposed to improve obstacle detection capability of indoor mobile robot. In this system, firstly, the Hue, Saturation, Intensity (HSI) color space conversion of images was performed. Secondly, a small target threshold selection method was proposed to segment the images, which enhanced the precision of the image segmentation. Thirdly, the target scene matching method and target projection matching method were used to calculate the change of the target pixel and projection so as to judge whether the target is obstacles or ground graphs. The experimental results show that the monocular vision system is effective and feasible, and this system can be applied to the navigation for small indoor mobile robots.
    Structural description model for video
    FU Mao-sheng LUO Bin WU Yong-long KONG Min
    2012, 32(09):  2560-2563.  DOI: 10.3724/SP.J.1087.2012.02560
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    How to present video effectively is the focus and difficulty in the field of multimedia research. A structural description model for video was proposed in this paper. Using the intrinsic structural characteristics of video, the video correlative graph model was constructed, with the shots of video as vertexes of graph, and the similarity between shots as arcs. The spectral properties of video correlative graph were extracted, including the leading eigenvalues, the eigenmode perimeter, eigenmode volume, Cheeger number, inter-mode adjacency matrices and inter-mode edge-distances. Video clustering and video surveillance experiments show the structural description model for video is feasible and effective, and the leading eigenvalues show better performance.
    Rotation-invariant non-rigid point matching algorithm based on graph matching
    LIAN Wei
    2012, 32(09):  2564-2567.  DOI: 10.3724/SP.J.1087.2012.02564
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    To address the rotation-invariant non-rigid point matching problem, a graph matching based algorithm was proposed in this paper. Two sets of edges were constructed from two point sets respectively. Then oriented Shape Context (SC) distances and length differences were both used to measure the similarities of edges between two point sets. Based on edge similarities, point correspondence was recovered via graph matching. The experimental results show the method is capable of achieving good matching results and also robust and efficient.
    Large-capacity blind steganography algorithm for color images based on visual perception mechanism
    KANG Nian-jin CHEN Zhao-jiong
    2012, 32(09):  2568-2572.  DOI: 10.3724/SP.J.1087.2012.02568
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    Most existing steganography algorithms for color images are designed by directly applying steganography for gray-scale images to color channel without employing color visual perception mechanism. A large-capacity blind steganography algorithm for color images based on visual perception mechanism in YUV space was proposed. The main idea is to analyze the local complexity of the carrier image via standard deviation on the Y component, split the message into two parts using the color visual perception mechanism, and then hide them in Y and V components respectively. Being less flexible, the U component was simply used as an information indicator. A large number of experiments were carried out showing that the proposed algorithm still maintains good imperceptibility compared with other methods after embedding large-capacity information, and can resist both the histogram contrast and RS steganalysis. Thus, the proposed algorithm is reasonable, easy to implement, and effective.
    Enhancement algorithm for color images based on co-occurrence matrix
    YANG Bing-qing TIAN Xiao-ping WU Cheng-mao
    2012, 32(09):  2573-2575.  DOI: 10.3724/SP.J.1087.2012.02573
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    Considering that the traditional method of histogram equalization can make the image produce unnatural enhanced results, a new color image contrast enhancement approach was proposed, which equalized color components by dependently using co-occurrence matrix. Firstly, gray correlative characteristics of pixels were combined in 3×3 neighborhoods to construct a co-occurrence matrix. Secondly, the method of co-occurrence histogram equalization was applied to luminance component only and the chrominance components were preserved. Finally, dark channel prior was used to solve the problem mentioned above to obtain the ideal image. Comparing the proposed enhanced algorithm with the other three typical enhancement algorithms, it is shown that the proposed algorithm not only considers the whole and local image information, but also deals with the histogram spikes and halo effect. The experimental results demonstrate that the proposed method can enhance the color images effectively.
    Automatic stitching and regulating algorithm for wide-angle images based on speed-up robust feature
    WANG Tie-jian LIU Yan-li
    2012, 32(09):  2576-2579.  DOI: 10.3724/SP.J.1087.2012.02576
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    Wide-angle images are very helpful when stitching panoramas. However, the severe deform in wide-angle images usually results in stitching failure. Focusing on such a problem, an automatic stitching and regulating algorithm for wide-angle images was proposed. The matching pairs of feature points were calculated to obtain the stitching matrix at first in order to stitch wide-angle images. Then the correcting matrix for the image was calculated based on the rotating angle of the lens so that a regulation could be made on the perspective distortion. It is shown from experiments that the perspective distortion can be effectively removed from the panoramic view obtained with the presented algorithm.
    Fibonacci optimized UMHexagonS algorithm for H.264 motion estimation
    LI Shi-ping ZHENG Wen-bin SHI Xin
    2012, 32(09):  2580-2584.  DOI: 10.3724/SP.J.1087.2012.02580
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    In order to overcome the shortcomings of using fixed search step and existing redundant search point in UMHexagonS algorithm of H. 264 motion estimation, this paper combined the Fibonacci sequence with center-biased feature to improve it. Firstly, the search step was determined by the progressive relationship of the Fibonacci sequence. Secondly, some search points which lead to redundant computation were deleted. At last, the search template of big hexagon was modified by the center-biased feature. The experimental results show that the new algorithm maintains the bit rate and Peak Signal-to-Noise Ratio (PSNR) of UMHexagonS, and reduces the time of motion estimation. And with the improvement of image elements, image complexity and search range, the time for motion estimation becomes less and less, and it can be reduced by an average of 23. 82% of the motion estimation time of UMHexagonS algorithm when the search range is 64.
    Satellite cloud image fusion based on regional feature with nonsubsampled contourlet transform
    WANG Da,BI Shuo-ben,WANG Bi-qiang,YAN Jian
    2012, 32(09):  2585-2587.  DOI: 10.3724/SP.J.1087.2012.02585
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    The fusion of different satellite cloud images can provide more comprehensive information for surveillance and early warning of disastrous weather. A satellite cloud image fusion algorithm based on regional feature with NonSubsampled Contourlet Transform (NSCT) was proposed. Firstly, the source images were decomposed at multi-scale and multi-direction by NSCT. Then the self-adaptive fusion rule based on regional correlation coefficient and regional energy was used to fuse the low frequency coefficients, and the fusion rule of regional variance in combination with weighting was used for the fusion of the high frequency coefficients. Finally, the fused image was obtained by performing the inverse NSCT on the fused coefficients. The experimental results illustrate that while the texture and edge feature of the fused cloud image are enriched, the infrared information are preserved as much as possible and the proposed algorithm acquires better fusion result.
    Face recognition method based on DLPP-SIFT
    LI Zheng-yi,FENG Gui-yu,ZHAO Long
    2012, 32(09):  2588-2591.  DOI: 10.3724/SP.J.1087.2012.02588
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    The Scale Invariant Feature Transform (SIFT) algorithm is robust to the feature extraction of face image. However, the feature data derived by SIFT is of high dimension, and is difficult to be handled. Therefore, a Direct Locality Preserving Projections-SIFT (DLPP-SIFT) algorithm was proposed. In the algorithm, SIFT was used to extract feature, and the subspace method with Locality Preserving Projections (LPP) was utilized for dimension reduction. This algorithm solved locality preserving problem via simultaneous diagonalization; therefore, the singularity of the matrix was avoided. The experiments on ORL and FERET face databases show that the proposed algorithm reduces the computation complexity and matching time of features successfully, and is more robust than SIFT, Principal Component Analysis (PCA)-SIFT and LPP-SIFT methods.
    Information security
    Cyclical nature of matrix sequence in image information security processing
    ZHONG Jin,WANG Da-gang
    2012, 32(09):  2592-2594.  DOI: 10.3724/SP.J.1087.2012.02592
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    Concerning the non-destructive information hiding in the image processing, the concept of the shift register of matrix sequence linear transformation in finite field Fq was proposed. The inherent law of scrambling transformation cycle for n-dimensional Arnold model transformation was revealed. Attributing the cycle scrambling transformation to cyclical problem of transformation matrix for modulo a prime number, the cycle of modulo the power of a prime number was determined, and the cycle of modulo a composite number was calculated. Cyclical calculation method of transformation matrix in the image information processing can achieve greater capacity of information embedded and less image distortion, and extract confidential information to realize non-destructive restoration of the original host image.
    Digital image scrambling technology based on three dimensional sub-affine transformation
    ZOU Wei-gang CHEN Pei-yun HUANG Jiang-yan
    2012, 32(09):  2595-2598.  DOI: 10.3724/SP.J.1087.2012.02595
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    In order to improve the security and flexibility of digital image information hiding, adopting the theory of sub-affine transformation, a new image encryption algorithm based on three dimensional sub-affine transformation was designed. By analyzing the constraints of three dimensional sub-affine transformation, according to the relation between variables and randomness of variables, a rapid construction method of three dimensional sub-affine transformation was given. Three color components of each pixel in the color space chose different ways to transform for achieving image scrambling, and its periodicity was discussed, for proposing the concept of singularity point and fake period. The experimental analysis shows that the algorithm has good effect of scrambling, larger key space, flexible encryption, and high security. And its diffusion and disturbance are ideal.
    Color image encryption algorithm based on cutting spectrum and 2D Arnold transform
    GONG Li-hua ZENG Shao-yang ZHOU Nan-run
    2012, 32(09):  2599-2602.  DOI: 10.3724/SP.J.1087.2012.02599
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    To reduce the heavy transmission burden of multichannel color image encryption algorithms, a single-channel color image encryption algorithm based on cutting spectrum and 2D Arnold transform was presented. In the proposed algorithm, the R, G, B components of the original color image were extracted, and their spectra were obtained separately by the Fractional Fourier Transform (FrFT) of different orders, followed by cutting their spectra to construct a new spectrum, then the combined spectrum was scrambled by the 2D Arnold transform to confuse and diffuse the spectrum information well enough. The encrypted image was a gray image, thus the transmission burden was reduced apparently while the main information of the original color image was kept. The simulation results and performance analyses verify the validity and the security of the encryption algorithm.
    Lexical active attack on chaotic text zero-watermarking
    LI Jing FANG Ding-yi HE Lu
    2012, 32(09):  2603-2605.  DOI: 10.3724/SP.J.1087.2012.02603
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    The conventional steganalysis techniques does not work in zero-watermarking technology because it does not modify carrier text. However, active attack model on text zero-watermarking has not been well studied. In order to solve this problem, an active attack algorithm for text zero-watermarking was proposed. Making use of synonym substitution technology, sync-attack and birthday-attack were defined. Through combining the two active attack methods, a lexical active attack algorithm on text zero-watermarking was designed and implemented. The experimental result shows the proposed algorithm can effectively destroy zero-watermarking without modifying carrier text massively.
    Intrusion detection model based on LISOMAP relevant vector machine
    TANG Chao-wei LI Chao-qun YAN Kai YAN Ming
    2012, 32(09):  2606-2608.  DOI: 10.3724/SP.J.1087.2012.02606
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    Concerning low classification accuracy and high false alarm rate of current intrusion detection models, an intrusion detection classification model based on Landmark ISOmetric MAPping (LISOMAP) and Deep First Search (DFS) Relevant Vector Machine (RVM) was proposed. The LISOMAP was adopted to reduce the dimension of the training data, and RVM based on the DFS was used for classification detection. Compared with the Principal Components Analysis (PCA)-Supported Vector Machine (SVM), the experimental results indicate that the LISOMAP-DFSRVM model has lower false alarm rate with almost the same detection rate.
    Strategy selection model for network survivability based on stochastic game
    LIANG Xiao MENG Xiang-ru ZHUANG Xu-chun WU Wen
    2012, 32(09):  2609-2612.  DOI: 10.3724/SP.J.1087.2012.02609
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    To improve the survivability of networks, a strategy selection model based on stochastic game was proposed. According to the damage impact on system made by the attacker behavior, the game process was divided into the resistance phase, the recognition phase, and the recovery phase. The relationship between the transition of system state and strategy selection was depicted from a specific view, based on it, a strategy selection analytical method was presented. A representative network example was provided to verify the feasibility and validity of the proposed method in the prediction of attacker behavior and decision of optimal strategy.
    Trust management model based on value-at-risk evaluation with changing time in P2P network
    GUO Yi-fan LI Teng GUO Yu-cui
    2012, 32(09):  2613-2616.  DOI: 10.3724/SP.J.1087.2012.02613
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    The trust management models in Peer-to-Peer (P2P) network mainly have two problems. For one thing, the different influences on value of trust between short-term trading and long-term trading are usually ignored. For another, the lack of the specific risk analysis on trading resources exists. Consequently, focusing on the quality of different nodes and its opposite risk value, this paper introduced the concept of risk factor with setting up its value and proposed a trust management model based on evaluation of value-at-risk with changing time. From the simulation results, a higher efficiency on resisting malicious actions in P2P network is achieved, and it has confirmed to select better traders effectively with a deeply quantitative analysis of trade resources through the model.
    Effective immune measures on P2P botnets
    FENG Li-ping HAN Qi WANG Hong-bin KANG Su-ming
    2012, 32(09):  2617-2619.  DOI: 10.3724/SP.J.1087.2012.02617
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    For deeply analyzing the factors that affect the prevalence of P2P botnets, the formation of a Peer-to-Peer (P2P) botnet was portrayed from dynamic perspective. Firstly, the differential equation model was formulated according to the formation of P2P botnets, which considered the effect of immunization on computer malware propagation. Furthermore, effective immune ratio of eliminating P2P botnets was calculated by analyzing steady condition of equilibrium in the model. Finally, the effective immune region was obtained and verified by deterministic simulation and stochastic simulation, respectively. The results show that the outbreak of P2P botnets can be effectively prevented by reasonable immune measures.
    Analysis of weakened immunization strategy on complex network
    TIAN Si LI Hui-jia ZHAO Yue
    2012, 32(09):  2620-2623.  DOI: 10.3724/SP.J.1087.2012.02620
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    In this paper, a specific epidemic weakened immunization strategy for the weighted network was studied based on that the classical immunization behaviors proposed in the current epidemic spreading study would cut off edges connected on the network structures when immunizing the epidemics, and result in the reduction of the network efficiency. The Susceptible-Infective (SI) model of epidemic spreading was constructed under which the evolution equation of density of infected nodes was deduced. Theoretical analysis indicates that the epidemic spreading rate is closely related to network heterogeneity, and the size of nodes' degree and network efficiency will influence epidemic spreading. Meanwhile, the weakened immunization strategy achieves the purpose of limiting the epidemic spreading rate and reserves the necessary network efficiency via weakening the weight value of edges therefore decreasing the spreading speed. Computer simulation results verify the feasibility of theoretical model and the rationality of weakened immunization strategy. Finally, the weakened immunization strategy was effectively applied to the local world and target immunization on controlling epidemic spreading.
    Ontology representation and realization of extended permission in RBAC
    ZHOU Jia-gen YE Chun-xiao
    2012, 32(09):  2624-2627.  DOI: 10.3724/SP.J.1087.2012.02624
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    Role Based Access Control (RBAC) has deficiency in characterizing permissions, so an extended RBAC model with permission hierarchy was presented. To utilize advantages of ontology in knowledge representing and reasoning, an ontology based representation and realization method of the extended model was proposed. Web Ontology Language (OWL) was used to formalize the ontology of this model, and some specific reasoning rules in the model were defined by Semantic Web Rule Language (SWRL). Implicit knowledge about authorization was derived through rule based reasoning. Based on this, explicit and implicit authorization views were generated for security analysis through the SPARQL Protocol and RDF Query Language (SPARQL). Finally, a case study was introduced to show the feasibility of the method.
    Typical applications
    Adaptive combination forecasting model for logistics freight volume based on area correlation method
    ZHOU Cheng ZHANG Pei-lin
    2012, 32(09):  2628-2630.  DOI: 10.3724/SP.J.1087.2012.02628
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    The forecasting performance of combined model is typically influenced by the combination weights assignment. A new combination weights assignment approach based on area correlation method was proposed. This study applied grey model, Polynomial Trend Extrapolation Model (PTEM) and Triple Exponential Smoothing Model (TESM) to develop a combination forecasting model to predict logistics freight volumes, in which the coefficients of combination weights were determined by area correlation method. The new method based on area correlation method shows its superiority in determining combination weights, compared with some other combination weight assignment methods such as equal weight method, entropy weight method and reciprocal of mean absolute percentage error weight method. Since area correlation method can comprehensively evaluate both the correlation and fitting error of forecasting model, it is an effective approach to determine the combination weights.
    Collaborative ordering models of multi-echelon inventory system based on hybrid demand
    XIONG Hao
    2012, 32(09):  2631-2633.  DOI: 10.3724/SP.J.1087.2012.02631
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    To make the ordering model more fit to the actual operation of the supply chain, the collaborative ordering models of multi-echelon inventory system based on the hybrid demand were constructed. These models assumed that only the demand of the most downstream node in the supply chain was independent demand, and the demand of all the other upstream nodes were related demand. And the related demand was a massive demand, so its inventory cost structure was different from the one of the independent demand. Therefore, after analyzing the cost structure of the multi-echelon inventory system with hybrid demand, the collaborative ordering models allowing or not allowing out of stock of determined demand system were given. In addition, the collaborative ordering model of the uncertain demand system was also constructed based on the safety stock analysis. Then the genetic algorithms of these models were given. And, the simulation shows that they are good ways to get satisfying order policy.
    Exact algorithm for generating optimal homogenous strip T-shape layouts
    JI Jun LU Yi-ping ZHA Jian-zhong CUI Yao-dong
    2012, 32(09):  2634-2637.  DOI: 10.3724/SP.J.1087.2012.02634
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    This paper presented an algorithm for generating the homogenous strip T-shape layouts for large-scale rectangular piece packing. The algorithm not only achieved good results within reasonable time, but also met the shearing and punching process need. The algorithm generated optimal homogenous strips, solved knapsack problems to obtain the strip layouts on the sections and the section layouts on the segments, and optimally selected two segments to compose the layouts. The algorithm was tested on 63 benchmark problems, and compared with five famous algorithms (the classic two-stage, the general T shape, the two-stage homogenous block, the general cutting pattern and the heuristic algorithm TABU500). The computational results indicate that the algorithm is efficient in both the computation time and the material utilization rate.
    Application of virtual simulation technology in network closed-loop control
    XU Shu-ping
    2012, 32(09):  2638-2642.  DOI: 10.3724/SP.J.1087.2012.02638
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    It is very hard to have a transparent and prompt interaction between user and remote controlled object due to uncertain time delay over the Internet, which severely limits the performance of network control systems. In order to solve the problem of random delay, a kind of three closed-loop network control structure based on virtual simulation was proposed. In accordance with the idea of open-loop system to achieve closed-loop control, this method constructed the virtual controlled object model in the client, made the operation states of virtual simulation system be similar or even identical to those of actual system, while allowing the operator to decide the next control instruction according to the operation of the virtual simulation system, so as to accurately give the required control instructions to the actual system, which ultimately achieved the purpose of remote real-time control. The simulation results show the validity and feasibility of the proposed method.
    Humanoid robot gait planning based on 3D linear inverted pendulum model
    YU Guo-chen LIU Yong-xin LI Xiao-hong
    2012, 32(09):  2643-2647.  DOI: 10.3724/SP.J.1087.2012.02643
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    In order to real-time adjust the humanoid robot gait, a humanoid robot gait generation method was proposed. The robot motion was simplified to the inverted pendulum motion of the three-dimensional linear model, and passed the pre-planned Zero Moment Point (ZMP) trajectory. According to the Center of Mass (CoM) and ZMP relations, the CoM trajectory was obtained. The front side gait and lateral gait were simplified into seven-link and five-link structures, the triangle theorem was used to calculate the angle of each joint, and the ZMP equation was introduced to discuss the stability of the walking process. The system simulation was done according to given conditions and combined with the actual system and its operation conditions were analyzed to verify the validity of the proposed planning method.
    Airport capacity analysis for typical parallel runways based on simulation method
    LI Xiong LI Dong-bin WEI Dong-xuan
    2012, 32(09):  2648-2651.  DOI: 10.3724/SP.J.1087.2012.02648
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    The parallel runway system is the most popular configuration in airport multi-runway construction. Four types of representative parallel runways (space between 400m, 760m, 920m and 1525m) and corresponding operation modes were simulated by using Simmod. The Ultimate Capacity (UC) and Factual Operation Capacity (FOC) of parallel runways were analyzed taking consideration of runway crossing and non-runway crossing. The simulation result shows that in instrument flight rule, the FOC of widely spaced parallel runways was about 74 sorties per hour, the FOC of medially spaced parallel runways was about 65 sorties per hour, and that of closely spaced parallel runways was only more than 40 sorties per hour. In condition of non-runway crossing, the capacity of parallel runway system would be increased by 13%.
    Reverse logistic networks optimization of home appliances return based on combined location routing problem
    ZHANG Jun
    2012, 32(09):  2652-2655.  DOI: 10.3724/SP.J.1087.2012.02652
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    Concerning the low recovery rate caused by high costs and low margins of the reverse logistics of the waste home appliances, the paper put forward a method which adopted the application of Discrete Particle Swarm Optimization (DPSO) to optimize the reverse logistics network model of the waste home appliances. After analyzing the structure and elements of the reverse logistics network model of the waste home appliances based on integrated location-routing problem, random swap sequence and Partially Mapped Crossover (PMX) operator were introduced to make DPSO possess overall and partial searching ability for intelligently optimizing and solving the model. The simulation results illustrate that the globally optimal solution achieved through this optimization model and algorithm has good convergence and effectiveness, at the same time, it can reduce the total cost of reverse logistics of the waste home appliances effectively.
    Transmission dynamics feature of enterprise marketing networks
    QIN Xiao-hong HUANG Guang-qiu
    2012, 32(09):  2656-2659.  DOI: 10.3724/SP.J.1087.2012.02656
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    In order to understand and explain the transmission mechanism, based on propagation behavior and topology structure characteristics of enterprise marketing network and Susceptible-Infected-Removed (SIR) model, the paper introduced the indexes of node transmission rate and edge weight, and then established transmission dynamics model of enterprise marketing network. The enterprise marketing network epidemic threshold was analyzed and simulated. The results indicate that the bigger the indexes of node transmission rate and the edge weight are, the smaller the propagation threshold is, which is more helpful for product and product information transmission. Finally, the authors put forward a few suggestions from the perspectives of reducing the spread of critical value and improving actual propagation rate.
    Information fusion based interference solution in electronic toll collection system
    WANG Liang LU Hua-xiang JING Wei-ping CHEN Tian-xiang
    2012, 32(09):  2660-2663.  DOI: 10.3724/SP.J.1087.2012.02660
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    Traditional solutions deal with following-car interference and adjacent-lane interference in Electronic Toll Collection (ETC) system separately, and are of low efficiency and high cost. In order to solve this problem, a solution based on information fusion, which can deal with these two problems together, was proposed. This method used the vehicle information collected by an ETC system as known information and chose the features of the vehicle image to verify whether the vehicle information came from the car in question. Then D-S evidence theory was adopted to fuse the results of verification and make a final decision whether it was the right car to be charged. An improved method for D-S evidence theory was proposed to ensure its validity when the results of consistency verification conflicted with each other. The experimental results show that this method can highly reliably detect illegal vehicles and solve both following-car interference and adjacent lane interference problems in ETC system.
    Feasibility analysis on method of calculating ADS-B latency
    CHENG Qing
    2012, 32(09):  2664-2666.  DOI: 10.3724/SP.J.1087.2012.02664
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    This paper proposed a method to accurately calculate ADS-B report latency in order to improve the surveillance accuracy of Automatic Dependent Surveillance-Broadcast (ADS-B) for the ADS-B latency had great influence on the surveillance accuracy. The time interval of two adjacent reports and the relevant two adjacent aircraft positions could be calculated on the basis of Time Of Receiving (TOR) and content of ADS-B reports. Then the different latencies were calculated by differencing the two time intervals. Given that the Time Of Measure (TOM) as the initial report time or a certain interval time, all the subsequent latencies could be measured and corrected. The authors carried out the feasibility analysis using Microsoft Excel by randomly selecting a aircraft ADS-B reports in 15min, 25min and 45min for ADS-B reports. The results show that ADS-B surveillance accuracy has been greatly improved within 10 meters, which can meet the requirement of airport surface surveillance.
    Precise damage analysis on active load section of protective engineering
    YUAN Hui WANG Feng-shan
    2012, 32(09):  2667-2671.  DOI: 10.3724/SP.J.1087.2012.02667
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    To meet the simulation need about the damage features of active load section of protective engineering, precise damage analysis was designed on module and workflow mechanism. Following the current rule of military damage phenomena and simulation design, the precise damage analysis function and module were described by models, the UML use case and its design goal of such system were clearly put forward. On the basis of cell modules, which were optimally decomposed from the precise damage analysis on active load section of protective engineering, the modular designing idea and logical frame were advanced, the function model and data flow mechanism were erected, and the precise simulation damage analysis was carried out based on window thread design. Finally, a case study shows its good alteration, which provides the effective simulation tool for the essential vulnerability about the active load section of protective engineering.
    Multi-source heterogeneous data fusion model in mobile geographic information system
    LI Wen-chuang ZHANG Yong-ping PAN Yu-chun
    2012, 32(09):  2672-2674.  DOI: 10.3724/SP.J.1087.2012.02672
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    In order to enhance the organization and management efficiency of multi-source heterogeneous data in field data collection process for mobile Geographic Information System (GIS), based on the analysis of the limitations of the existing methods and structural features of the data, a new kind of fusion model based on EXchangeable Image File (EXIF) was proposed in which the digital image was used as carrier to fuse the information of spatial location and general attributes. In the proposed model, associated spatial information and general attributes were embedded into digital image to achieve the purpose of being highly integrated. A field data collection system was designed and developed based on the model, and applications of this system in the fields of agricultural resources management and decision analysis verify the validity and actual result of the model.
    Underground pipe network spatial analysis in large plant with ArcGIS
    XIAO Jing-feng WANG Xiao-dong YAO Yu
    2012, 32(09):  2675-2678.  DOI: 10.3724/SP.J.1087.2012.02675
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    To resolve the problem that underground pipe network of plant is large, complex and difficult to manage, the C/S+B/S mixed development model based on the ArcGIS platform was used. This paper aimed to transfer the spatial analysis of the traditional Geographic Information System (GIS) from C/S to B/S. Collision detection algorithm and efficient linear interpolation method were used in B/S client, and moreover an optimized relational database management model was proposed. The system running results show that the system could make spatial analysis of the invisible underground pipe network better and more effective, and achieve the digital management of underground pipe network in large plant.
    E-commerce recommendation platform based on SaaS pattern
    LIU Jia HUI Cheng-feng DU Xing-zhong CHEN Zhen-yu
    2012, 32(09):  2679-2682.  DOI: 10.3724/SP.J.1087.2012.02679
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    Some E-commerce sites cannot deploy independent recommender systems themselves due to limited resources. In order to help these sites deploy recommender systems quickly and conveniently, an E-commerce recommendation platform based on Software-as-a-Service (SaaS) pattern was proposed and implemented. This platform used unified scripts to collect user action information and provided recommendation services through standard interface. It realized a low coupling between platform and E-commerce sites so that the cost of implementation was reduced. The results of online operations show that this platform can help E-commerce sites increase the conversion rate and the volume of orders.
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