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Table of Content

    01 July 2007, Volume 27 Issue 7
    Network and communications
    Global Active Bandwidth Adjustment (GABA) Algorithm
    2007, 27(7):  1559-1561. 
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    In recent years theIn recent years, there has been a more and more serious phenomenon that the unresponsive flows such as UDP have occupied the bandwidth of responsive flows such as TCP. An algorithm called GABA (Global Active Bandwidth Adjustment) algorithm was proposed with the cooperation of edge routers and core routers. Core router got the information of unresponsive flows and edge router blocked invalid unresponsive flows. The NS2 experiment proves that GABA can improve the network utilization and the bandwidth fairness.
    Multisource application level multicast system based on P2P net model
    2007, 27(7):  1562-1565. 
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    An application level multicast system based on net model was implemented. In this system, a single peer node could receive media data from many peer nodes by searching the index group. Experimental results show that this system has shorter delay than the tree structure system when peer nodes invalidate, and has better robustness.
    Deploying nodes scheme in line wireless sensor networks
    2007, 27(7):  1566-1568. 
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    The monitoring region of line wireless sensor network is close to a line. While base station is collecting sense data, the region closer to the base station need transmit more data. If general scheme of deploying sensor nodes uniformly is used, sensor nodes near the base station will use up energy soon and the base station cannot collect data anymore. Therefore, a density formula was proposed to deploy sensor nodes by investigating energy consumption in line wireless sensor networks. Theoretical analysis and simulation result show, in the case that monitoring region is wide, deploying sensor nodes by this scheme, the lifetime is prolonged to two times that of uniform deploying.
    Analysis of facility location in network
    2007, 27(7):  1569-1571. 
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    Where to put servers in network to provide more effective service to customer can be classified as facility location problem. The problem was formalized by defining virtual service level agreement (SLA) between facilities and customers. The normal local search algorithm in static problem was modified from one step to two to fit the network. The locality gap of Kmedian algorithm of partition low service quality service and incapacitated facility location problem of low service quality service were pointed out. The test results show that the algorithm can reduce the computation time effectively with a little rising of locality gap.
    Design of collision aware MAC protocol for wireless sensor network
    Chuan-Shu Liao Ping Han
    2007, 27(7):  1572-1575. 
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    The wireless sensor network is event triggering network, which contains many nodes. The concepts of same source collision and different source collision were put forward. The collision caused by identical event triggering several nodes movement was regarded as same source collision and the collision caused by different events triggering different nodes movement was regarded as different source collision. All these two collisions can cause the decline of network data stream and the waste of nodes energy. Therefore, it is necessary to realize collision avoidance for MAC layer based on existing MAC protocol of wireless sensor. The collision aware MAC (CAMAC) using the idea of filter and power control was proposed. The principle of CAMAC handling different collisions was discussed, and CAMAC was simulated by NS.
    Research and implementation of MIPv6 in high performance router
    2007, 27(7):  1576-1578. 
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    The background and characteristics of mobile IPv6 (MIPv6) were investigated. The architecture of high performance router such as Tbit router of national digital switching system research center (NDSC) was researched. MIPv6 was designed and implemented on Tbit router SRT880T, which supported high routing quality, so as to provide a good foundation for future development and implementation of MIPv6.
    Multiparty video transmission method in distributed cooperative system
    2007, 27(7):  1579-1581. 
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    The distributed multiparty video cooperative system usually suffers problems of the low scalability, low realtime performance under heavy payload and single point failure, if all video streams are relayed by a video server in centralized way. A distributed multiparty video transmission scheme was proposed. A mesh overlay network with low delay was constructed by measuring the delay between cooperative peers for every cooperative group. The topology maintenance mechanism was designed to ensure transmission of video streams. Video streams in a cooperative group were transmitted in pure distributed way where cooperative peers receive multistreams from their neighbor peers in terms of the "pulling" method. Furthermore, under the condition of bandwidth changing and peers churning, an adaptive control mechanism of encoding rate was used to ensure that every cooperative peer can receive multistreams in time. The simulation results indicate that the method of distributed multiparty video transmission has higher scalability, better realtime performance and stronger robustness than that in the centralized way.
    Design and implementation of general interface adapter for integrated network management
    2007, 27(7):  1582-1584. 
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    A general interface adapter was designed to adapt the existed protocols and deal with the interconnection and intercommunication. Design pattern and the open source project Openadaptor Framework were applied to the implementation of the interface adapter. This method can decrease the complexity, improve the efficiency of system development and software reuse, and solve the core technique problem in integrated network management platform.
    Realization of high accessing speed to campus servers through DNS load balance technology
    2007, 27(7):  1585-1586. 
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    The bottleneck between Cernet and public net restricts the rapid access to the information published by high schools. The technologies of domain name system (DNS) load balance and Web acceleration were introduced, which bypassed the obstacle among the networks. It realized the high information fetching speed of campus server applications.
    Design and implementation of a topology discovery system for networks
    2007, 27(7):  1587-1590. 
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    Based on the analysis of present network topology discovery methods, a topology discovery system for networks was designed and implemented, which gained topology configuration information from multisources, automatically discovered topology by level and displayed topology by hierarchy. Compared with traditional topology discovery systems, this system has lower design complexity. And the topology map discovered by this system is more complete, and much easier to be observed.
    Articles
    New anticounterfeit system of identity documents based on logic signing technique
    2007, 27(7):  1591-1593. 
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    A new secure mechanism using logical signing technique was proposed to protect identity documents against forgery, tampering and illegal possession. And it is applied to the anticounterfeit system of identity documents so as to make it verified realtime and offline. It is an open system totally independent of databases and networks, and it is cryptographically secure due to the close logical association between synthetic information and verification information of identity documents.
    New offline divisible and fair electronic cash scheme
    2007, 27(7):  1594-1596. 
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    Divisibility of ecash helps expend digital coin exactly. Most divisible ecash schemes are based on binary tree, but few ecash schemes offer fairness and divisibility at the same time. Based on binary tree, blind signature and zeroknowledge proof, a new fair indivisible electronic coins scheme was proposed.
    Communication model of attribute authority and attribute registration authority in PMI and its formal description
    2007, 27(7):  1597-1598. 
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    There are many states in attribute authority (AA) and attribute registration authority (ARA) communication, and its transformation is complicated. An AA and ARA communication model in privilege management infrastructure (PMI) was proposed, which could avoid insecure middle states. The finite state machine was used to formalize the proposed model, and to prove the secure state of the model.
    Digital watermarking algorithm based on wavelet moment modulating
    2007, 27(7):  1599-1602. 
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    To enhance the capacity to resist attacks such as rotation and cropping, an algorithm based on wavelet moment modulation was proposed. Wavelet moments are invariant to rotation, translation and scaling change of the host image, and they also have wavelets ability: to observe signal with multiresolution. An imperceptible watermarking was hidden in a host image by modulating the wavelet moments of the host image. The experimental results in section 3 and section 4 show that this algorithm can effectively resist signal processing attacks, such as filtering, compression, especially rotation and cropping, and the detection does not need the host image.
    Forward security provided key exchange and mutual authentication protocol in wireless environment
    2007, 27(7):  1603-1605. 
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    An efficient and secure mutual authentication and key exchange protocol, FS-MAKEP (Forward SecurityMutual Authentication Key Exchange Protocol) was proposed. It is suitable for applications in lowpower mobile communications. It maintains the required level of security and has the property of perfect forward secrecy which is not possessed by other protocols such as ES-MAKEP, L-MAKEP, and I-MAKEP. Moreover, a formal proof to guarantee the security of the proposed protocol was given. At last,the computation costs of FS-MAKEP and ES-MAKEP were compared.
    Anonymous communication mechanism based on group padding MIX approach
    2007, 27(7):  1606-1608. 
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    The Mix mechanism has provided a feasible solution to the realization of anonymous communication. But to a certain degree, the attackers can still obtain the correspondence relations through traffic analysis. In order to further improve the ability of Mix mechanism to resist the traffic analysis of message volume, a kind of scheme named group padding was proposed, and based on which, a new anonymous correspondence mechanism was designed. Algorithm analysis and the simulation results show that, compared with the traditional Mix mechanism, the newly proposed Mix mechanism based on group padding scheme can resist traffic analysis of message volume effectively, and needs lower extra bandwidth at the same time.
    Periodically renewed multisecret sharing scheme
    2007, 27(7):  1609-1610. 
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    A new multi-secret sharing scheme was proposed based on elliptic curve cryptography and PANG-WNAG’s (t, n) multisecret sharing scheme. The scheme has properties as follows: (1) participants can choose subsecrets by themselves; (2) shadows of every participant can be renewed periodically. Compared with PANG-WANGs scheme, this scheme compensates for the disadvantages of the original scheme such as subsecrets must be chosen by dealer and shadows cannot be renewed,so this scheme has better flexibility and higher security.
    Multimedia DRM scheme using modulated motion vector for handset
    2007, 27(7):  1611-1612. 
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    A new digital rights management (DRM) of video was proposed. It modified the motion vector (MV) of macro block (MB) for mobile device. Experimental results indicate that the proposed DRM can not only achieve very low cost of the encryption, but also enable separable authentication to individual mobile devices, such as portable multimedia player (PMP) and personal digital assistants (PDA).
    Design and implementation of malwebpage detection system based on honeyclient
    Xiao-Yan SUN Yang WANG Yue-fei ZHU Dong-ying WU
    2007, 27(7):  1613-1615. 
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    Now, Internet Explorer is the most popular client software which malwares often use. In allusion to such threats to Internet Explorer, the characters of Web attack were analyzed, and a malwebpage detection system based on honeyclient was designed, in which spider was combined with honeypot. In the system, spider was used to collect source of urls, then clientengine automatically created Internet Explorer processes, and devicedriven detector was used to detect malwares coming through Internet Explorer. In the end, the malicious webpages url was added to the black list and the malware database was enlarged.
    Architecture of planar protective secure file system
    2007, 27(7):  1616-1618. 
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    After analyzing the characteristics of traditional security file systems, it was pointed out that these systems have several problems in data availability and system performance. Then a new architecture of security file system was proposed based on stackable file system to integrate the security services that a storage system should provide. The experimental results show that the new system makes a good tradeoff between security and performance.
    Graphics and image processing
    Comparative analysis on rectangular nonuniform sampling algorithm and log polar transformation algorithm of image
    2007, 27(7):  1619-1622. 
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    The images peripheral area is blurry and some details may be lost with logpolar transformation(LPT). So the rectangular nonuniform sampling algorithm (RNS) was proposed. In the method, the size of central area was adjusted according to actual requirements and the central area was sampled uniformly. The peripheral area was layered and the sampling rate in every layer was uniform. Along with the increase of the distance apart from the center, the sampling rate was gradually reduced. The data quantities of classical LPT variable parameter LPT (VPLPT) and RNS were compared. In general, the calculating quantity of rectangular algorithm is the least. The distortion of image caused by LPT can be overcome. The algorithm can be easily implemented with hardware.
    Reversible data hiding by histogram gap method based on integer wavelets
    2007, 27(7):  1623-1625. 
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    A histogram gap method for image lossless data hiding based on integer wavelet transform and histogram modification was proposed. The data was hidden into wavelet coefficients of high frequency subbands, which conformed to the human vision system. Then the data was embedded into the gap by iteratively generating gaps in wavelet coefficient histogram, and the histogram modification technique was used to prevent overflow. Experimental results demonstrate the superiority of the proposed method over the existing methods. That is, the proposed method has a larger embedding capacity (payload) in the same visual quality (PSNR) or has better visual quality in the same capacity.
    Spherical harmonic illumination algorithm based on linear subspaces
    2007, 27(7):  1626-1628. 
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    The algorithm of drawing the virtual image scene was analyzed, and a spherical harmonic illumination algorithm based on linear subspaces was proposed. From the object model to get the subspaces, the lowdimensional linear subspaces were extracted and the spherical harmonics representing Lambertian reflection was used as a convolution, considering the diffuse interreflected transfer simultaneously. Experimental results demonstrate that the algorithm approaches accurately with high quality.
    MumfordShah approach for image segmentation with multiindex flexible energy
    2007, 27(7):  1629-1633. 
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    The MumfordShah functionality model is more and more important for image processing. Chan and Vese proposed a level set method based on the simplified MumfordShah model for image segmentation. CV model was improved in two respects: First, new inner and outer energy with flexibility were constructed, instead of traditional rigid energy, which decreased the phenomena of numerical oscillation and deeper segmentation; Second, inner and outer energy based on multiimage information were constructed to improve the segmentation ability and precision of CV model. Finally, a MumfordShah based approach for image segmentation with multiindex flexible energy was proposed via above two points. New model can deal with the image with high noise pollution and inner gray variety. The experiments on synthesized images, magnetic resonance image (MRI) and real world images show the capability of this method, and it is faster convergent and robust.
    SAR image denoising using multiple wavelet domains Besov balls projections
    Xia-Fei HUANG Yue-Song LING Hua-Jie CHEN
    2007, 27(7):  1634-1636. 
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    Different smoothing regions of SAR image can not be represented accurately in single wavelet domain. In order to solve this problem, a Besov ball projections algorithm in multiple wavelet domains was proposed. Different Besov balls radius were defined by the universal hidden Markov tree model and Besov norm, then an image was projected onto alternate Besov balls of proper radius corresponding to the projection onto convex sets algorithm based on preserving edge and strong scatterers (SPOCS) for image denoising. Experimental results demonstrate that this method can not only provide significant improvement over conventional algorithms based on single wavelet domain, but also preserve edge structure better.
    Method for filtering image contaminated with strong Gaussian noises
    2007, 27(7):  1637-1640. 
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    A new joint method for filtering image contaminated with strong Gaussian noises was presented. The pixels of an image were divided into two sets. Strong noisy pixels were located firstly through estimating changes of pixel intensity in a local region of a pixel and were removed using a modified adaptive mean filter. Weak noisy pixels were smoothed with a simplified pulsecoupled neural network (PCNN). Experimental results show that the proposed method works well with both preserving edge and smoothing range adaptively in an image, compared with some existing image filtering methods.
    Quick simplification for LOD terrain with dynamic multiresolution based on quad tree
    2007, 27(7):  1641-1643. 
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    Quad tree and multiresolution technique are the most efficient ways to express and display complex terrains. After an overall research of former algorithm, an improvement was made for LOD terrain simplification based on quad tree. A valuation system suitable for multiresolution was made,and a new bidirectional way was given to recover the cracks according to distance. It simplifies the terrain efficiently and increases the rendering speed.
    Corrective algorithm of flat areas occurring in TIN constructed from contours
    2007, 27(7):  1644-1646. 
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    In TIN of digital elevation model constructed from contours, flat areas which are made up of flat triangles can not reflect the real shape of the surface, so that they need be corrected properly. A corrective algorithm of flat areas was presented by the method. The TIN which flat areas were corrected could simulate the real shape of the surface to the fullest extent and could improve the speed of correcting flat areas, in which the inner flat triangles are divided of having no use of terrain characteristic lines. The time complexity of the algorithm is O(n).
    Application of swarm intelligence in image processing
    2007, 27(7):  1647-1650. 
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    The concept and features of swarm intelligence were introduced. The applications of swarm intelligence in image processing were mainly discussed. On the basis of that, an indepth analysis and discussion on the image processing approaches based on swarm intelligence from the human visual system and bionics point of view was given. It was compared with the traditional image processing approaches. Swarm intelligence benefits from the characteristic of colony and makes some image feature emerge with the selforganization of agents in the image environment by constructing some form of elementary unit cluster.
    Image retrieval algorithm based on edge color distribution
    2007, 27(7):  1651-1653. 
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    A new image retrieval algorithm based on edge color distribution was proposed. The content information of an image was characterized by color distribution of different edge types described by twodimension edge color histogram. The algorithm takes not only the local color features into account but also the space distribution information of edge types and overcomes the shortcoming of color histogram which loses the location information. Experimental results show that this method effectively improves the image retrieval performance compared with other retrieval methods.
    ROI progressive image transmission algorithm based on human visual specialties
    Da-Wei ZHOU Jin-Ling GENG Ji-Ming ZHENG
    2007, 27(7):  1654-1656. 
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    In conventional region of interest (ROI) progressive image transmission algorithms, human visual specialties are not taken into account. An improved algorithm based on the properties of wavelet transform and human visual specialties was proposed. Firstly, an image with low resolution was transmitted so that user could decide if the image was needed. On the condition that there is no impact on the subjective quality of ROI, the transmission of ROI coefficients which are not important for visual quality could be delayed. And the bandwidth could be utilized to transmit the important back ground (BG) coefficients. Furthermore, depending on the bit rates, an expansion factor was evaluated. To guarantee the image with better visual effects, the transmission of BG image was controlled by the expansion factor. The experimental results show that the improved algorithm is effective and the expansion factor can accommodate image transmission.
    Intelligence perception
    Robust head segmentation method based on level set model in complex scenes
    2007, 27(7):  1657-1659. 
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    In office setting, head segmentation becomes difficult in the scene with occlusion or frequent brightness change. To deal with such problems, a robust head segmentation method based on level set model was proposed. After head level set model was constructed by sign distance function, the difference between head level set model and sign distance function of an image was added to ChanVese segmentation formula. Then a new EulerLagrange formula was obtained. When the evolvement of the sign distance function in the new EulerLagrange formula stopped, the head segmentation was finished. The experiments were implemented separately in office setting with scenes of twoperson occlusion, Gaussian noise, and brightness change. Compared with ChanVese segmentation, the provided head segmentation method is robust to above three complex scenes.
    Face recognition based on (2D)2NMF and its improvement
    2007, 27(7):  1660-1662. 
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    Non-negative matrix factorization (NMF) is an effective method for partsbased feature extraction, and it can deal with partial occlusion and some illumination problems. However, the bases learned via NMF are not orthogonal. Translating an image into a vector often loses the structure information of pixels and leads to a high dimensionality. By adopting the image matrix instead of image vector, (2D)2 NMF method was presented to extract the 2D features of an image, so the performance of the method was improved by the NMF bases orthogonalization and image diagonalization. The experimental results show the improved performance compared with the traditional NMF and 2DNMF.
    Moving object segmentation based on Markov random field and active contour model
    2007, 27(7):  1663-1666. 
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    A method extracting moving object was proposed by utilizing the Markov random field (MRF) and active contour model in video sequences. Firstly, a rough motion template was obtained by motion detection based on Markov random field model and through postprocessing. Secondly, after extracting the initial contour of the object, the energy function of active contour model was constructed. Finally, the solution of minimizing the energy function was obtained by using the modified greedy algorithm, after which, the precise contour of the object was extracted. The experimental results show that the proposed algorithm can effectively segment and extract moving object in video sequences.
    Estimation of photographic object distance based on facial features
    2007, 27(7):  1667-1669. 
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    Aiming at estimating the photographic object distance from facial image, a method was proposed based on the theory of anthropometry in face and projective geometry. Firstly, the points of nosewing and the corners of eyes and mouth were selected to estimate a facial model within the facial plane. Secondly, the correspondence between the image plane and the location of threedimensional facial region was established based on the distribution of facial features inside the facial region and projective theory. Finally, the photographic object distance was computed by using anthropometry statistics. Without requiring any auxiliary equipments, the proposed method is easier to be implemented than traditional ones, and therefore has a better practicability.
    Audio-video continuous speech recognition and phone segmentation based on dynamic Bayesian network
    2007, 27(7):  1670-1673. 
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    Two single stream dynamic Bayesian networks (DBN) models based on the improvement of the whole word state (WWS) DBN model were built for audio and video continuous speech recognition and phone segmentation. Different from the WWS DBN model in which a word is regarded as being composed of several states, directly, in our DBN model, a word is regarded as being composed of its corresponding phones. As a consequence, both world and phone level recognition results can be achieved with their time boundaries. The results of recognition and segmentation experiments show for recognition of audio stream, compared with hidden Markov model (HMM), DBN model has improvement of 12.79% in single noise ratio range from 0dB to 15dB. Segmentation results on audio show both DBN model and HMM have similar performance. Simultaneously, for recognition from video stream, compared with HMM, improvement of 2.47% is achieved. Finally, the asynchronous relationship of audio and video stream is analyzed, which provides the foundation for using the multistream DBN model to make audiovideo continuous speech recognition and determine the asynchronous relationship of audiovideo stream in the future.
    Articles
    Adaptive speech pitch detection based on LVAMDF
    Kang-Jie Zhang Huan Zhao Ju-Hua Rao
    2007, 27(7):  1674-1676. 
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    According to the limitation and the stability of the speech pitch, the LVAMDF method was improved, and an adaptive speech pitch determination method was proposed. In the unstable speech, the exact speech pitch was acquired according to the trough in the current window and the window before by the simple troughselect system; in the stable speech, the times of the speech pitch comparison was reduced, and the computing cost was decreased. The method for searching the beginning and ending point of the sonant was improved. Thus, more accurate points could be acquired. Simulations show that the pitch extracting results of the improved method reduces the rate of the half and double speech pitch points in different SNR environment.
    Application of omnivision in robot independent localization
    LU Jun
    2007, 27(7):  1677-1679. 
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    A method based on the omnivision was studied for the selflocation of mobile robot. According to optical principle, the omnivision sensor was designed. By using the omnivision sensor, robots panoramic image in working environment was obtained. With the aid of noise reduction, color threshold segmentation and center point computation and so on, the landmarks in the panoramic image were recognized. By using triangulation method, the robots position was obtained, which was a good basis for the navigation and the collision of robot. Experimental results prove that the method is feasible for the selflocation of mobile robot.
    Subspace clustering method for high dimensional data stream
    Hong Shen
    2007, 27(7):  1680-1684. 
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    Inspired by the FP algorithm used in mining frequent patterns and the idea used in CLIQUE which is a classical method for clustering static data, a new data structure named dense gridtree (DGtree for short) was proposed to record the synopsis of the data streams for clustering. Then the clustering problem was transformed to the problem of constructing a DGtree and searching for dense grid cells in the DGtree. With the help of DGtree, the subspace containing clusters was found. Experimental results show that this method has good cluster quality.
    Measurement of C4ISR system coupling based on DoD architecture framework
    2007, 27(7):  1685-1687. 
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    A measuring method of the C4ISR system coupling was proposed. Firstly, the use rate of channel between systems was calculated by the periodicity, speed, size of data interchange between systems, which was based on the description of C4ISR system architecture by the DoD architecture framework. Secondly, the coupling of the system was reflected by the use rate of channel. Lastly, it is proved that the measuring method satisfies the five measurement rules provided by Briand.
    Densitybased spatial clustering method with obstacle constraints
    2007, 27(7):  1688-1691. 
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    Current spatial clustering algorithms in the presence of obstacles, such as COD_CLARANS, DBCLuC, AUTOCLUST+ and DBRS+, were studied and compared. Then a new method of densitybased spatial clustering called DBCOD was proposed which could handle the obstacle constraints in a new way. In DBCOD, obstructed distance was used to replace Euclidean distance in DBCLuC as the criterion, and a polygon combination and reduction method was used in the preprocessing stage to improve the efficiency. Simulation results show that this new proposed approach not only has the advantages of densitybased clustering algorithms, but also takes advantage of the obstructed distance to make the results more reasonable than traditional ways.
    Effective hybrid clustering algorithm based on partition and hierarchy
    2007, 27(7):  1692-1694. 
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    A new hybrid clustering algorithm in phase (HCAP) of highefficiency and good quality was put forward on the foundation of synthetically analyzing Kmeans clustering algorithm based on partition and agglomerative clustering algorithm based on hierarchy, and consulting some improved hybrid clustering algorithms. The strategy, description and capability analysis of the HCAP were presented. Experimental results on simulating sample data of planar data space show that the HCAP is effective and reasonable, and is better than old algorithms at some aspects.
    Improved density biased sampling algorithm
    2007, 27(7):  1695-1698. 
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    Uniform random sampling is widely applied to many kinds of algorithms in data mining. It processes uniform distribution data set extremely effectively, but easily loses slight cluster and consequently decreases clustering accuracy, when the processing data set is skew distribution. A gridbased density biased sampling algorithm (G_DBS) was proposed. It got approximate density biased samples through scanning data only one time. Our experimental evaluation shows that G_DBS algorithm not only improves the accuracy of clustering, but also is insensitive to noise and has high efficiency. It is one of the effective solutions to mass data mining.
    Study and implementation of searching technology based on SVG standard
    Peng Wang Li Yan Shi Tingting
    2007, 27(7):  1699-1701. 
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    In practice terms, it is impossible to avoid a great deal of spatial data processing when publishing with SVG document through Internet. Therefore, it not only slows down the executing speed but also expend too much the resource of computer system when searching the spatial data in SVG document. It was proposed to store the SVG document into ORDBMS, and to use the extended SQL (SQL3/SQL99) to make searching. At the same time, another storing and searching method based on native XML database (NXD) was also executed, using XQuery language for searching approach. The results show that both of SVG searching methods of database are very efficient and take less system resources than publishing the document directly on client side.
    Chromatogram data compression based on linear fitting of time series
    2007, 27(7):  1702-1704. 
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    A new segmenting algorithm of time series was proposed to satisfy the requirement of processing chromatogram data of welllogging. The key points that denote the varying trend of the sequence were selected according to some thresholds through one scan of the data. These selected points were used to fit time series linearly. The experimental results show that this algorithm can eliminate the noises without loss of the rough shape, and find the inflexion and the peak subsequences accurately.
    Design and realization of views materialization algorithms
    2007, 27(7):  1705-1707. 
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    The information is stored at the data warehouse in form of views. According to cost, some views are selected to answer queries in the data warehouse. The cost model of view materialization was presented. The solution and strategy using genetic algorithm and improved algorithm were given. Finally, experimental results show that the proposed algorithms can deliver a similarly most optimal solution.
    Multi-variable decision tree construction algorithm based on rough set and entropy
    2007, 27(7):  1708-1710. 
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    Multivariable decision tree is effectively used in the classification of data mining. The key to building lies in the reasonable choice of attributes combination based on the interconnection between attributes. The traditional method is achieved by the relative core of attributes, which is incomplete. A new alternation algorithm was offered. In this algorithm, the number of attributes contained by each node was restricted, and then, attributes combination was selected according to the redefined attribute dependability and the distance function based on condition entropy. In the end, an example was given to show that the method decreases the height of tree, and increases the explanation of classification.
    Component retrieval method based on casebased reasoning and XML
    2007, 27(7):  1711-1714. 
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    Based on the analysis of current component retrieval methods, a framework of software component retrieval with intelligence based on case-based reasoning (CBR) and XML was discussed. The methods of the XML-based knowledge presentation of the components in the repertory and the similarity evaluation between the component case and problem requirement were emphasized. A kind of recursive algorithm for calculating the case similarity was provided.
    Approach to judge consistency of DTDs
    2007, 27(7):  1715-1716. 
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    DTD has been widely used as the schema language for XML documents. A DTD describes the structure of a collection of similar XML documents. The consistency of XML DTDs concerns the question that given a DTD D, is there any finite XML document that conforms to D. The notion of the consistency of DTDs was formalized, and a judging method of the consistency for DTDs was given.
    Research into coexistence between different versions of SNMP
    Jian-Qun CUI Li-Bing WU De-Bao XIAO
    2007, 27(7):  1717-1719. 
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    It is an efficient way to exchange messages between different versions of simple network management protocol (SNMP) by version transform agent. After analyzing the differences in message formats, PDU formats and MIB structures among different versions, the version coexistence problem was solved by implementing the coexistence of PDU, message and management information in the version transform agent. The method can improve the compatibility of network management software.
    Semantic Web service composition supporting If-Then-Else control structure
    Ling Jiang Guang-zuo Cui
    2007, 27(7):  1720-1724. 
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    Web service composition enables the cooperation of multiple Web services to finish certain task. Because compositions with simple sequence control structure cannot satisfy the need of more complicated cooperation. A way of semantic Web service composition which supports the IfThenElse control structure was proposed. Using the introduced composer, users can do visualizable composing at domain knowledge level. And the execution engine based on knowledge base supports the execution of composition result with IfThenElse control structure.
    Test method for Web Services based on extended WSDL mutation
    2007, 27(7):  1725-1728. 
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    Testing the interoperability of Web Services is important for the correct implementation of Web Services. A method for Web Services based on extended WSDL mutation was proposed, and an algorithm to generate mutated WSDL document was designed. This method applied mutation operators to WSDL document in order to generate mutated Web Services interface that was used to test the definition error and logic error in the Web Services. At last, the example shows that the test method is effective.
    Discussion and application of object-level communication between ActiveX controls and Web server
    Fang MIAO
    2007, 27(7):  1729-1731. 
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    The ActiveX controls are widely used in Web application development. But many ActiveX controls are independent of the Web server, or have low degree of communication with it. In the environment of .Net, C#, ASP.NET, XML and javascript were used to achieve the objectlevel communication between ActiveX controls and Web server. The application system added new factor while its structure was not affected. This technology has been applied to some projects successfully.
    Artificial intelligence
    Optimization of multilevel hierarchical transshipment system in logistics transportation based on fishswarm algorithm
    2007, 27(7):  1732-1736. 
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    A largescale nonlinear optimum programming model to solve the optimization problem of multilevel hierarchical transshipment system in logistical transportation was established. In the optimization model, the solving space was discretized based on actual consideration of space constraints of variables and precision of solutions; the policy of discretization was to create grids with certain size within space of variables, and the optimal locations for all transfer stations at each level of a multilevel hierarchical transshipment system were selected from all known coordinate points. Because the dimension of the model was enormous, an improved fishswarm algorithm was used to solve the problem. In the improved algorithm, two matrices describing the relation between transfer stations of all levels with angular points of grids and the relation between two adjacent levels transfer stations were established to delete constraints and compress greatly variables of the model; an evolutionary algorithm based on evolutionary similarity was applied to mix the basic properties of global and local search; the selfadaptive delta variation operator, dual arithmetic crossover operator, peakjump operator were used to improve the behaviors of artificial fishswarm algorithm. An application result shows that the speed and reliability of the optimization algorithm is improved greatly.
    Optimization of fuzzy logic control based on immune-GA and application in CNC machining
    2007, 27(7):  1737-1740. 
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    The immune-genetic algorithm (GA) was used to optimize the fuzzy logic control. The method of optimizing membership functions, scale factors and quality factors was presented; the converge speed and stability were improved because the diversity was maintained and the learning process was led by immuneGA. The simulation and application in computer numerical control (CNC) machine process with this method show that the proposed method has better performance compared with other methods.
    Adaptive ant colony algorithm based on dynamic weighted rule
    2007, 27(7):  1741-1743. 
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    Firstly, the basic idea of the ant algorithm was introduced. Then a modified ant colony algorithm was presented. The algorithm overcame the default of slowconvergence and stagnation phenomenon in the classical ant colony algorithm, and introduced a weighting idea in the updating of pheromone. Experimental results show that this algorithm has much higher capacity of searching global optimal result than some classical ant colony algorithms. It can obtain a very good balance between the convergence rate and the stagnant phenomenon.
    Weighted rough set model
    2007, 27(7):  1744-1747. 
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    Weighted rough set (WRS) model is an extension of rough set (RS), based on variable precision rough set (VPRS) model. This model considers the noise tolerant capability and the objects importance. Especially, it provides a profitable tool for extracting rules from experience knowledge. In weighted rough set model, some basic concepts were redefined in approximation space. Also, reduction concept was put forward under weighted rough set model. At last, from the experiments, that the WRS is the extension of RS is verified, and how objects importance affects reduction is illustrated.
    New dependability of attribute sets
    2007, 27(7):  1748-1750. 
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    A new conception of attribute sets dependability was proposed, and the calculating method was given. The meaning of attribute sets dependability based on the character was discussed compared with single dependability. It is concluded that the attribute dependability is more authentic.
    New algorithm for multimodal function optimization based on immune algorithm and Hopfield neural network
    2007, 27(7):  1751-1753. 
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    Based on the analysis of immune theory and Hopfield neural network (HNN), a new algorithm for multimodal function optimization was proposed. This new algorithm had the advantages of both HNN and immune algorithm (IA), and it showed excellent characteristics in optimization of multimodal function. In detail, a group of solutions with variety were taken by IA first; and then the solutions were partitioned into some clusters. Finally cluster centroids returned by clustering algorithm were taken as the initial value of each HNN, and Hopfield neural networks were used to obtain all minima. The experiments show that this new algorithm is an effective method for multimodal function optimization. Compared to immune algorithm, the efficiency and precision are both improved.
    Solving for complex functions with high dimensions based on hybrid particle swarm optimization
    li Li Hong-Qi LI
    2007, 27(7):  1754-1756. 
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    A new hybrid particle swarm optimization combined with genetic algorithm was proposed in order to solve complex questions with high dimensions and overcome prematurity and the weak ability of local search. The global solution can not be found because of the bad results of some dimensions, and it is difficult to find all the best value in each dimension using the usual optimization algorithm. Enlightened by genetic algorithm, the improved algorithm can find the best position through evaluating each dimension and picking out the bad ones, adopting mutation and improving it during the process of evolution. Experimental results on several benchmark complex functions with high dimensions show that the algorithm can rapidly converge at high quality solutions.
    New function optimization algorithm based on gridding
    2007, 27(7):  1760-1759. 
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    A new determinate optimization algorithm based on gridding for function optimization, gridding optimization algorithm (GOA), was proposed. The strategy of generating gridding was based on nodes. Especially for high dimension problems, a new random gridding generating method was introduced, which well solved the problem that population size would increase exponentially with the increase of dimension. The characteristics of GOA were introduced. The effectiveness of this method is proved through experiments compared with fast evolutionary programming (FEP) and genetic algorithm (GA).
    Application of an improved gene expression programming in functions modeling
    2007, 27(7):  1760-1762. 
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    A new gene expression programming (GEP), PGEP, was proposed. It was based on three new operators: good subspace operator based on the best ones stored strategy; variable reorganization, conversion probability and variable mutation probability operator based on global convergence strategy; variable dimension subspace operator based on population search strategy. The result shows that PGEP behaves better than GEP in functions modeling.
    Peer-model in computer-supported collaborative learning
    2007, 27(7):  1763-1766. 
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    The construction of peermodel is the key to select peer in computer supported collaborative learning (CSCL). The peermodel was built, which included the main factors for learning group formation. The peermodel was described formally. The expressions of dynamic and collaborative information on peer, such as peer learning schedule, knowledge level, cognitive capability, and collaborative capability, were studied.
    User-oriented model of ontology evolution
    2007, 27(7):  1767-1769. 
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    By now, many industrial and academic applications have adopted ontology as their conceptual backbone, and the ontology evolution becomes the key to these applications. A fourphase evolution process was proposed, which was composed of change request, change capture, change implementation and exception handle. The main contributions of this model are: dynamic adaptation of the ontologybased system to the changes in the exterior environment and easy control of the evolution process.
    Nonlinear network traffic prediction based on BP neural network
    2007, 27(7):  1770-1772. 
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    The traditional network traffic analysis is based on linear model, but the traffic actually behaves as a nonlinear system due to complex topology and network behavior. With a large amount of real traffic data collected from the actual network, a nonlinear network traffic model based on artificial neural network (ANN) theory was constructed to predict the network traffic. Compared with the traditional linear module, this model has better precision, adaptability and robustness.
    Dynamic selfadaptive tabu search algorithm for grid scheduling
    2007, 27(7):  1773-1775. 
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    A method based on tabu search (TS) for grid scheduling was proposed and different neighborhood architectures were designed to minimize the makespan. Considering the dynamic characteristic of grid, batchmode scheduling was utilized and partial scheduling information was exploited to modify the next partial scheduling strategy and adaptively adjust the algorithm parameters. Finally, the algorithm was implemented in GridSim environment. The simulation results demonstrate that the proposed algorithm is superior to some heuristic classical algorithms.
    Typical applications
    Shanghai city spatial information system for application and service based on spatial information grid
    Bai-Lang YU Jian-Ping WU Ai-Li CHEN Da-Jun QIAN
    2007, 27(7):  1776-1779. 
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    The architecture, technologies and implementation of the Shanghai city spatial information system for application and service, a SIG (Spatial Information Grid) based platform was introduced. In the system, there were ten categories of spatial information resources, including city planning, landuse, real estate, river system, transportation, municipal facility construction, environmental protection, sanitation, urban afforestation and basic geographic information data. In addition, spatial information processing services were offered as means of GIS Web Services. The resources and services were all distributed in different Webbased nodes. A single database was created to store the metadata of all the spatial information. A portal site was published as the main user interface of the system. There are three main functions in the portal site. First, users can search the metadata and acquire the distributed data by using the searching results. Second, some spatial processing Web applications developed with GIS Web Services, such as file format conversion, spatial coordinate transfer, cartographic generalization and spatial analysis are offered. Third, GIS Web Services currently available in the system can be searched and new ones can be registered. The system has been working efficiently in Shanghai government network since 2005.
    Foundation excavation co-evolution based on particle swarm optimization
    Chen Qiu-lian Tao-shen LI
    2007, 27(7):  1780-1782. 
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    As a multilevel optimization problem, foundation excavation optimization concerns many constraint conditions. With the analysis in hierarchy and relation of level design, a new collaborative optimization algorithm was proposed, which was distributed, hierarchical and of coevolution. Collaborative optimization was integrated with particle swarm optimization to speed up the evolution and simply the optimization process. Collision and disposal in optimization of subsystems, which belong to coevolution optimization system, were analyzed. At last, an experiment of parallel collaborative design with "anchored piles in row and waterproof curtain" was given to show its effectiveness.
    Bi-level programming model and algorithm of freeway inflow control based on networking toll
    2007, 27(7):  1783-1785. 
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    Aiming at the freeway inflow control problem, the application scenario and solution strategies of bilevel programming model were proposed. The multivehicle bilevel programming model was presented to solve the problem on freeway network inflow control. A new algorithm, GAA algorithm, which combined genetic algorithm and Aloplex algorithm was put forward. A simplified example was given to show that GAA algorithm excels to the genetic algorithm in solving bilevel programming problem, calculates the objective value in the case of various vehicle types less than that in the case of simple vehicle type, and improves the utility of expressway network.
    SIP-based embedded video monitoring system
    2007, 27(7):  1786-1788. 
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    An embedded video monitoring system based on session initiation protocol (SIP) was proposed. Its monitoring device equipped with embedded Linux system communicates with the monitoring center in the way of SIP. Through SIP the monitoring center can open and close video monitoring, adjust monitoring parameters on the monitoring terminal, e.g. brightness, contrast and tone. Furthermore, the monitoring terminal can carry out automatic monitoring. When the monitored objects change unexpectedly, the monitoring terminal will send an alarm to the monitoring center. SIP application in video monitoring system not only extends its physical scope, but also promotes monitoring intelligence.
    Fuzzy control of twowheel difference speed steering in automated guided vehicles based on vision
    2007, 27(7):  1789-1791. 
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    The principle and composition of a twowheel difference speed steering automated guided vehicles (AGV) based on machine vision guiding were simply introduced. The problems about the computer control system design, image information recognition and so on were also generally stated. The fuzzy controller design was put forward to control the twowheel difference speed steering AGV. The Simulink and experimental results show that the twowheel difference speed steering AGV controlled by the fuzzy controller can move steadily, follow path reliably, and get good control performance.
    Design and implementation of embedded networkattached recording system
    2007, 27(7):  1792-1794. 
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    Embedded system, network storage and optical storage are very popular nowadays. Networkattached DVD recording system based on embedded system is the combination of the three technologies. One embedded networkattached DVD recording system based on virtual local recording was designed and implemented. The design of this system was particularly described, and the threelevel cache architecture and the strategy of cache management based on producer/consumer model were emphatically introduced. At last, the corresponding testing and performance analysis were carried out.
    Data prediction and its application in online game
    2007, 27(7):  1795-1798. 
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    The data prediction in online game can make the online game run smoothly even the jam of network happens. Based on the real instance of the online game, a new method for data prediction based on attractor was proposed. It can predict the roles action in the scene more actually. Thus, even when the network transport is not very satisfying, the online game still can run smoothly.
    Consumer/provider pattern of MMORPG server logic
    2007, 27(7):  1799-1801. 
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    Based on GoF essential elements of design pattern, consumer/provider (C/P) pattern was introduced. It can effectively decouple game logic modules, which can implement independently, and offer relative provider interface to serving applicator. On the other hand, C/P pattern can decrease exponential problem resulted from adapterobject instantiation to linear effort, and avoid adapterobject release problem resulted from game logic relativity.
    Fault tree diagnosis method in flight control system combined with Bayesian
    2007, 27(7):  1802-1805. 
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    The complexity of aircraft ground maintenance always causes the blindness and low efficiency of ground crew during the debug process in flight service. For solving this problem, a method of the fuzzy fault diagnosis expert system based on fault tree theory was proposed. By using Bayes theorem to modify fuzzy relation formula, the quantitative relation equation was got and the decisionmaking step was given. Through the simulation, a flight control example was given and satisfying results were got.
    Solution to course scheduling problems based on genetic algorithm and tabu search
    2007, 27(7):  1806-1808. 
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    Course scheduling problem is a type of NPhard problems. Usually, it can be solved by utilizing genetic algorithm. Tabu search algorithm was combined with genetic algorithm to improve the performance. Furthermore, by altering the individual fitness computation method, the curriculum schedule polarization phenomena can be avoided. Experimental results indicate that the method is feasible and has better performance.
    Skew detection and correction method of document images based on improved Hough transform
    2007, 27(7):  1813-1816. 
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    The skew of document images originated from scanning will bring much trouble to page segmentation and optical character recognition (OCR). Although traditional standard Hough transform is insensitive to noise and discontinuous, it has limitation in application because of huge calculation. A skew detection and correction of document images based on improved Hough transform was presented. Textline direction extraction in multiresolution image and reasonable voting threshold selection were introduced to reduce the affect brought by image skew. Experimental results show that this method is effective and accurate in skew detection and correction of document images.
    Research and implementation of streaming media proxy caching based on patching algorithm
    2007, 27(7):  1817-1820. 
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    Proxy caching and scheduling algorithms of streaming media were analyzed. Combined with their advantages, an efficient method of streaming media proxy caching based on patching algorithm was designed and implemented. Experimental results show that the method can significantly reduce the consumption of aggregate bandwidth on backbone link and the original servers disk I/O, and can quicken the response.
    Study on Complicated Report Technique
    2007, 27(7):  1821-1824. 
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    Abstract:Development of software often produces reports with both complex form and complicated calculation. This paper based on the experience of the development, puts forward a template-driven and parser center report generation system, and expounds the generation of a great deal of report calculation model. Based on actual project reports’ feature, that focuses on defining XML mark system, designing parser explained then implement report generation, to reflect XML-based template development, crucial system componentialized, technical architecture and implementation.
2024 Vol.44 No.3

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