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Table of Content

    01 October 2011, Volume 31 Issue 10
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    Network and distributed techno
    Research on optimal thread quantity of real-time signals acquisition system
    WANG Ke-te WANG Li-sheng
    2011, 31(10):  2593-2596.  DOI: 10.3724/SP.J.1087.2011.02593
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    Aim at solving the problem of data processing and data demonstration in real-time signals acquisition system in multi-core and multi-thread environment, the authors exploited an efficient algorithm which used bare threads to build data acquisition module and data processing module with a set of optimal threads for allocation in order to make full use of parallel computation to increase the performance and real-time quality of the system. This algorithm worked based on producer-customer and the round-robin scheduling of operating system, referring to the workload of each module to tune the thread allocation solution to make the application achieve better speed-up ratio and real-time quality. The testing result of Field Programmable Gate Array (FPGA) hardware simulation system shows that in dual core environment, this algorithm can produce best combination of threads allocation with which waveform acquisition module and waveform display module can be executed in optimal parallel mode. And compared with other solutions of thread allocation, this solution spends less time in execution. Thus, this algorithm improves the speed-up ratio, computing and the real-time quality of the system. The optimal thread allocation algorithm provides the solution of optimal thread allocation which improves the efficiency of parallel application execution, reduces unnecessary spending of the thread and improves the real-time quality of waveform signal acquisition.
    Parallelization design of face recognition algorithm based on Matlab multi-core clusters
    ZHENG Xiao-wei YU Meng-ling
    2011, 31(10):  2597-2599.  DOI: 10.3724/SP.J.1087.2011.02597
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    In order to take full advantage of multi-core processor resources, the parallel programming model by building blocks with multithreading was studied, hence improving the performance of the program. According to the integral structure of Principal Component Analysis (PCA)-based face recognition algorithm, a functional module named train() was designed for the training of recognizing generated samples in the environment of Matlab cluster. The parallelization of this algorithm was realized by task partition. The experimental results indicate that the stable recognition rate of 94.167% and the approximately linear speed-up ratio verify the correctness and high efficiency of the parallel algorithm.
    Precision test method based on continued-fraction approximation
    XU Jin-chen GUO Shao-zhong ZHAO Jie WANG Qian
    2011, 31(10):  2600-2602.  DOI: 10.3724/SP.J.1087.2011.02600
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    Poor adaptability and slow convergence rate are the two main disadvantages of the existing precision test methods. To solve this problem, an elementary functions precision test method based on continued-fraction approximation was proposed by analyzing Unit in the Last Place (ULP) error and comparing several different functions true values calculations. The different calculations were analyzed and tested in the following two ways: time complexity and convergence degree. The experimental results show that the precision test method based on continued-fraction approximation is more effective, less complex and achieves faster convergence.
    Parallel ray tracing model based on .NET Remoting
    WANG Li-dong LI Chao-kui TAO Jian-jun YANG Gang
    2011, 31(10):  2603-2605.  DOI: 10.3724/SP.J.1087.2011.02603
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    Ray tracing algorithm needs a great deal of computation time. To improve its efficiency, a parallel ray tracing model, based on the image theory and the framework of .NET Remoting, was proposed in this paper. It scheduled and started the remote computing object, and assigned masks dynamically through computing the completion description with the sub-tree of secondary visual source. The comparison among numeric results indicates that the parallel model considerably reduces the computation time without losing precision. It can be applied to urban microcellular environments with arbitrary building layouts and heights.
    μC/OS-Ⅱ| same priority task| round-robin scheduling| real-time| module expansion
    YIN Zuo-wei GUO Bing SHEN Yan
    2011, 31(10):  2606-2608.  DOI: 10.3724/SP.J.1087.2011.02606
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    Since uC/os-II can not provide the restriction on same priority tasks,a strategy was proposed base on round-robin algorithm scheduling .It borrowed two priority tasks in the kernel as the clock source and the polling engine, so that tasks with the same priority work under the lowest priority in turns. The method allows the kernel to support up to 192 tasks in the same priority without losing the real-time. The experiment and comparison indicated that this project was more simple and practical than the one we already have.
    Design of video preprocessing IP core for online inspection system of elastomer workpiece
    LIN Hui WU Li-ming PAN Qi-jun
    2011, 31(10):  2609-2611.  DOI: 10.3724/SP.J.1087.2011.02609
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    In order to inspect the size and defects of elastomer workpiece in real-time, a video preprocessing IP core based on Processor Local Bus (PLB) was proposed and implemented. The structure of IP core and the hardware implementation of convolution were investigated. LOG filter was designed by System Generator, and ultimately the edge detection algorithm was implemented on Field Programmable Gate Array (FPGA). The experimental results indicate that compared to the traditional implementation of edge detection by software, method of IP core achieves higher speed, and needs only 40ms. It can satisfy the requirement of online inspection system of elastomer workpiece in real-time video preprocessing.
    Binary large object access algorithm based on file segmentation
    2011, 31(10):  2612-2616.  DOI: 10.3724/SP.J.1087.2011.02612
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    In the mass media data-storage system, too large data file or multi-user concurrent access can cause the failure of storage procedure. In order to improve the stability and the reliability of storing binary data file in storage system, Binary Large Object (BLOB) storage stability probability model was proposed and established. It had been proven that using more file blocks and smaller block size can increase the probability of successful BLOB storage. This paper also studied and improved the BOLB data access technology through the storage stability probability model. By establishing the storage structure based on file segmentation, a new algorithm of storing BLOB data and reassembling BLOB block was presented. The simulation and the application show that, BLOB storage algorithm based on file segmentation reduces the probability of failure during storing media files.
    Network and communications
    Network conversion gateway based on DSP and FPGA
    CHEN Ming SONG Bao TANG Xiao-qi
    2011, 31(10):  2617-2620.  DOI: 10.3724/SP.J.1087.2011.02617
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    With Digital Signal Processor (DSP) and Field Programmable Gate Array (FPGA) adopted as the kernel processors, the embedded network conversion gateway of high real-time was designed to realize the conversion between fieldbus and Ethernet. The conversion was finished on the physical layer and the data link layer, and the problem of direct communications between fieldbus and Ethernet was solved. The experimental results indicate that the feasibility and effectiveness of the design satisfy the requirements.
    Low-power NoC router design
    ZHOU Duan PENG Jing ZHANG Jian-xian ZHANG Han
    2011, 31(10):  2621-2624.  DOI: 10.3724/SP.J.1087.2011.02621
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    Concerning the power consumption of routers based on Network on Chip (NoC), the key factors that influence the router power consumption were studied on the systematic level, such as the number of virtual channels, the depth of buffer and the width of flit. A method of reducing power consumption was presented by incorporating various key factors of power consumption and making the virtual channels share the switch input port. And then a NoC-based router with low-power consumption was implemented. The experimental results show that the designed router has lower power consumption in comparison with the Alpha 21364 router and the IBM InfiniBand router.
    Efficient data collection algorithm in sensor networks with optimal-path mobile sink
    LI Bin LIN Ya-ping ZHOU Si-wang HUANG Cen-xi LUO Qing
    2011, 31(10):  2625-2629.  DOI: 10.3724/SP.J.1087.2011.02625
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    Mobile sink can efficiently collect data and extend the network lifetime. However, the existing researches about data collection based on mobile sink mainly focus on path-constrained mobile sink. Hence, a path-controlled traversal model for mobile sink data collection was constructed, and a data collection algorithm for mobile sink based on optimal-path traveling was proposed. The algorithm discretized the continuous path problem by local Voronoi grid, used the amount of data collected and system energy consumption as performance metric, combined taboo search algorithm to achieve the maximum amount of data collected and the minimum of network energy consumption traversing. Theoretically and experimentally, it is concluded that the proposed algorithm is able to solve the optimal-path traveling of data collection problem using path-controlled mobile sink.
    Multicast routing algorithm based on congestion control for NoC
    YUAN Jing-ling LIU Hua XIE Wei JIANG Xing
    2011, 31(10):  2630-2633.  DOI: 10.3724/SP.J.1087.2011.02630
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    The multicast routing method has been applied into the Network on Chip (NoC) since traditional unicast communication cannot meet the increasingly rich application requirements of NoC. Three kinds of path-based multicast routing algorithms including XY routing, UpDown routing and SubPartition routing algorithms were applied to 2D Mesh or Torus NoC. The congestion control strategy was proposed. The simulation results show multicast routing algorithms have shorter average latency and higher throughput and balanced applied load compared with unicast routing algorithms. SubPartition routing algorithm was confirmed to have a more stable and better performance as the network size increases. Finally, multicast congestion control techniques for NoC were employed to make multicast communications more efficient and enhance the NoC performance.
    Theoretical study on bandwidth utilization in FlexRay network
    WANG Gang DING Tian-bao RONG Jian ZHANG Zhuo Lü Yi-bin
    2011, 31(10):  2634-2637.  DOI: 10.3724/SP.J.1087.2011.02634
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    To improve the bandwidth utilization of a FlexRay network, it is necessary to gain a deep insight into this performance parameter. Based upon current model for time parameter optimization in a FlexRay network, through reducing a nonlinear operator to a linear one, analytical expressions of the optimal payload length of static frame and the maximum bandwidth utilization in the static segment of a FlexRay network were derived. The numerical experiments verify the validity of the analytical expressions, and demonstrate that the obtained analytical formulae are capable of providing an exact calculation for the bandwidth utilization in a FlexRay network.
    Overlap-based connectivity restoration approach for wireless sensor and actor network
    ZHAO Xin-yuan WANG Neng
    2011, 31(10):  2638-2643.  DOI: 10.3724/SP.J.1087.2011.02638
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    In Wireless Sensor and Actor Network (WSAN), the failure of an actor would bring about the loss of connectivity and more resource consumption of the sensors which belong to the failed actor. Thus, this paper proposed a new approach to restore the connectivity of WSAN. With 2-hop neighbor information, the approach determined whether the actor was local cut-vertex at first, and then calculated the migration distance of actor according to the overlap of management area among actors. Each actor created the recovery schedule list beforehand in distributed manner and broadcast it. Some neighbors of failed actor which belong to the recovery schedule list would perform restoration process in sequence with local cascading movements when failure occurred. The NS2 simulation results confirm the effectiveness of the approach.
    Weighted scheduling in multi-user orthogonal frequency division multiplexing system with proportional fairness
    HOU Hua LI Gen-xuan LIU Yan
    2011, 31(10):  2644-2649.  DOI: 10.3724/SP.J.1087.2011.02644
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    The traditional Orthogonal Frequency Division Multiplexing (OFDM) scheduling does not consider the proportional fairness among users' rates while allocating resource. To solve this problem, a new proportional fair scheduling scheme was proposed in multi-user OFDM system for heterogeneous classes of traffic in this paper; its users' queues carry heterogeneous classes of traffic. The scheme maximizes the sum of system's weight capacity under the constraint of the proportion among users' rates; provides different types of packets in users' queues different weight factor, and calculates the user's weight by the packet weight factor; not only defines the channel priority factor, but also allocates users sub-carriers by the factor under the constraint of the proportion among users' rates while allocating sub-carriers; finally derives a linear power allocation pattern. The simulation results and analysis demonstrate that the proposed scheme better satisfies users' requirements of throughput and strictly guarantees the fairness among users' capacity on the basis of improving system's throughput.
    Congestion control algorithm of non-linear high-order random early detection
    TIAN Shuo GAO Zhong-he
    2011, 31(10):  2650-2653.  DOI: 10.3724/SP.J.1087.2011.02650
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    With regard to the phenomena that Random Early Detection (RED) packet loss rate is high while the network congestion is not serious and vice versa, the congestion control algorithm of non-linear high-order RED was put forward to control the ineffectiveness of the network. The algorithm has established a high-order function model which has good congestion control ability. By using the non-linear control to mark or discard fragments with lower and higher probability near low and high threshold respectively, it can control average queue length effectively. Meanwhile, NS2 stimulation has verified that the algorithm is effective in improving the network performance.
    Adaptive active queue management algorithm based on internal model control
    LIN Kai-si LIN Kai-wu ZHANG Lu
    2011, 31(10):  2654-2656.  DOI: 10.3724/SP.J.1087.2011.02654
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    Real networks are of large delay and dynamics. According to the IMC (Internal Model Control) and improved control theory model with TCP/AQM, an active queue management algorithm suitable for the large delay network environment was designed to cope with the large delays. For the dynamics of the networks, the impact that the change of network parameter brings to the algorithm was analyzed to correct the algorithm parameter online. The adaptive active queue management algorithm suitable for the large delay network was acquired. The reliability of the algorithm has been verified by NS2 simulation.
    Improvement of wireless TCP based on monitoring error packet loss rate
    HU Han
    2011, 31(10):  2657-2659.  DOI: 10.3724/SP.J.1087.2011.02657
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    In wireless environment, TCP erroneously responds to all losses by invoking congestion control algorithm, which results in degraded end-to-end performance. Concerning this problem, this paper proposed a method of wireless TCP based on monitoring the packet loss rate due to bit error in real-time. The data sender cooperated with the router configured with the function of explicit congestion notification to distinguish the characteristics of packet losses; at the same time, the sender took advantage of the monitor result to adjust the TCP segment size. The simulation results show that the throughput of modified of TCP outperforms TCP_SACK and TCP_Reno by 100% approximately when the bit error rate is 1E-4.
    Information security
    Intrusion prevention system against SIP distributed flooding attacks
    LI Hong-bin LIN Hu Lü Xin YANG Xue-hua
    2011, 31(10):  2660-2664.  DOI: 10.3724/SP.J.1087.2011.02660
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    According to the research of distributed SIP flooding attack detection and defense, in combination with the characteristics of IP-based distributed flood attack and SIP messages, the two-level defense architecture against SIP distributed flooding attacks (TDASDFA) was presented. Two-level defensive components made up TDASDFA logically: the First level Defense Subsystem (FDS) and the Second level Defense Subsystem (SDS). FDS coarse-grained detected and defended SIP signaling stream to filter out non-VoIP messages and discard SIP messages of the IP addresses exceeding the specified rate to ensure service availability| SDS fine-grained detected and defended SIP messages using a mitigation method based on security level to identify the cunning attacks and low-flow attacks with obvious features of malicious DoS attacks. FDS and SDS detected and defended network status in real-time together to weaken SIP distributed flooding attacks. The experimental results show that TDASDFA can detect and defend SIP distributed flooding attacks, and reduces the probability of SIP proxy server or IMS server being attacked when the network is on the abnormity.
    Watermarking scheme for 3D models in combination with tendency detection of vertices
    WANG Xin-yu ZHAN Yong-zhao
    2011, 31(10):  2665-2669.  DOI: 10.3724/SP.J.1087.2011.02665
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    To improve the robustness of spatial watermarking schemes for three-dimensional models against various attacks especially the simplification, cropping and their combined attacks, a new watermarking scheme combined with tendency detection of vertices for three-dimensional models was proposed. In the scheme, the spherical coordinates of vertices were used to construct the ordered vertex sets and the vertex norms representing the model shape approximately were selected to be modified to embed watermark. Watermark was extracted based on the tendency of vertices variations achieved by comparing and counting the variations between the vertex norms of detected model and original model. The negative effect on watermark detection caused by cropping was reduced further by introducing the analysis on the rate of deleted vertices. The experiments show the scheme is robust enough against the common single attacks including translation, rotation, uniform scaling, vertex re-ordering, noise, simplification, cropping, quantization and subdivision and combination attacks. The smoothing attack also can be resisted to some extent. Thereby, the watermarking scheme can be applied to the copyright protection of three-dimensional models.
    Blind detection digital watermarking algorithm in DCT domain based on density of feature point
    QU Ju-bao LIN Hong-ji
    2011, 31(10):  2670-2673.  DOI: 10.3724/SP.J.1087.2011.02670
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    To solve the problem that the digital watermarking images suffer geometric attacks, a strong robust blind detection digital watermarking algorithm, integrated with the unchanged features of the image and the characteristics of the frequency-domain stability, was proposed. By constructing the self-adaptive Scale Invariant Feature Transform (SIFT) algorithm and filling the seats with the Harris method of the angle and the point, utilizing the density of feature points obtained in different scale space and adjusting the watermarking information self-adaptively to the intensity embedded into Discrete Cosine Transform (DCT) domain, it scrambled the image sub-block feature vector set with Arnold scrambling, and then generated the key documents, next matched the two-way feature with the secret image feature vector, got geometric distortion parameters and corrected the image restoratively, and extracted the IDCT inverse transform domain watermark information in the form of blind detection. Judging from the experimental results, the algorithmic Peak Signal to Noise Ratio (PSNR) in this paper improves by 13% than using Discrete Wavelet Transform (DWT) and Discrete Fourier Transform (DFT), and the similarity of watermark is over 11%. It shows that this algorithm has good robustness to both of the geometric attacks and the conventional signal processing, as well as better invisibility.
    PLL-based synchronization of rational dither modulation watermarking
    YAN Bin WANG Xiao-ming HAO Jian-jun ZHANG Ren-yan
    2011, 31(10):  2674-2677.  DOI: 10.3724/SP.J.1087.2011.02674
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    To resist desynchronization attacks, a watermarking scheme using Rational Dither Modulation (RDM) based on Phase-Locked Loop (PLL) was proposed. This scheme took account of two kinds of desynchronization attacks: translation and scaling. Watermark was embedded by RDM and detected by the framework of joint synchronization and decoding. The detector adjusted the estimated attack parameters in PLL according to the results of RDM decoder. Then the new estimated parameters were used to aid watermark decoding, so as to improve the decoding performance. The authors tested the performance of this watermarking system in different data models (DA/DD) and different interpolation algorithms. The simulation results show that this algorithm can resist translation and scaling attacks effectively.
    Blind detection resistant steganographic algorithm for images based on texture complexity and pixel-value difference
    TAO Ran ZHANG Tao PING Xi-jian
    2011, 31(10):  2678-2681.  DOI: 10.3724/SP.J.1087.2011.02678
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    According to the analysis on the effect of the texture complexity on steganalysis, the authors proposed a data hiding algorithm based on texture complexity and pixel-value difference. Firstly, the image was decomposed into blocks. Then, the texture complexity of each block was calculated and blocks with high complexity were selected. Then the pixel-value difference on two directions of the selected blocks was computed to determine the edge areas. The secret messages were only embedded in the pixel-value difference above the threshold. When compared with several steganographic methods on different image databases, the experimental results show that the proposed method outperforms previous steganographic methods such as LSB matching and adaptive data hiding in edge areas of images on the capability of resisting universal blind detection, such as wavelet high-order statistics analysis.
    Image encryption and sharing based on Arnold transform
    HOU Wen-bin WU Cheng-mao
    2011, 31(10):  2682-2686.  DOI: 10.3724/SP.J.1087.2011.02682
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    To improve the security of image sharing and encryption, an algorithm which combined the scrambling encryption with sharing technology and pixel diffusion was proposed. Firstly, the Logistic chaotic mapping algorithm was used to generate the parameter of Arnold transform. Secondly, two-dimensional Arnold transform with variable parameters was adopted to scramble pixel positions of the image. Finally, three-dimensional Arnold transform with variable parameters was adopted to diffuse pixel values of the scrambled image, so the image could be decomposed into two images. The experimental results show that the algorithm has a strong sensitive effect on the external keys, resists plaintext attack and differential attack effectively, and possesses favorable avalanche effect. Moreover, there is a close relationship between the internal keys and the original plaintext image.
    New three-party password-based authenticated key agreement protocol with elliptic curve
    LIU Zhu-wen LI Li-lin
    2011, 31(10):  2687-2688.  DOI: 10.3724/SP.J.1087.2011.02687
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    Password-based Authenticated Key Agreement (PAKA) protocols allow parties sharing only a low-entropy, human-memorable password to authenticate them and establish a common session key over an insecure channel in a secure manner. A new three-party password-based authenticated key agreement protocol based on the elliptic curve was proposed in this paper. The new protocol skillfully hid the password of each participant into the messages to ensure the security of passwords. The security of the new protocol was based on the discrete logarithm on elliptic curve, and the server did not need to be completely trusted. The results of security analysis and efficiency analysis show that the new protocol realizes the secure communications under the low computational cost.
    Anonymous credentials scheme based on ring signature for trust negotiation
    LI Wei FAN Ming-yu WANG Guang-wei YUAN Jian-ting
    2011, 31(10):  2689-2691.  DOI: 10.3724/SP.J.1087.2011.02689
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    At present, most of the privacy protection schemes are based on sophisticate zero-knowledge protocol or bilinear mapping computation, so their efficiency is low. In order to address this problem, an anonymous negotiation credentials scheme was proposed based on ring signature. On the foundation of anonymous credentials framework, an efficient discrete logarithm based ring signature scheme was constructed to protect the negotiation credentials, compared with two schemes proposed by ZHANG, et al. (ZHANG MING-WU, YANG BO, ZHU SHENG-LIN, et al. Policy-Based Signature Scheme for Credential Privacy Protecting in Trust Negotiation. Journal of Electronics & Information Technology, 2009(1): 224-227) and LIU, et al. (LIU BAILING, LU HONGWEI, ZHAO YIZHU. An efficient automated trust negotiation framework supporting adaptive policies. Proceedings of the Second International Workshop on Education Technology and Computer Science. Washington, DC: IEEE Computer Society, 2010: 96-99) the proposed scheme is more efficient.
    Self-healing group key management scheme with collusion resistance
    CAO Shuai ZHANG Chuan-rong SONG Cheng-yuan
    2011, 31(10):  2692-2693.  DOI: 10.3724/SP.J.1087.2011.02692
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    Random number and broadcast polynomial for every session were created. The legal nodes could recover the lost legal group keys by themselves independently according to their private information and broadcast messages, and the collusion attack between newly joined nodes and revoked nodes was resisted. New private information was distributed to revoked nodes so as to rejoin group in later sessions. Through the security and efficiency analysis, the scheme has less communication cost yet still achieves security property, suitable for mobile Ad Hoc network.
    Efficient RFID mutual authentication protocol
    WANG Ming-hui WANG Jian-dong
    2011, 31(10):  2694-2696.  DOI: 10.3724/SP.J.1087.2011.02694
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    For effectively ensuring users' privacy and data security of the Radio Frequency Identification (RFID) system, a new RFID mutual authentication protocol was proposed in this paper, which was designed by the method of combining elliptic curves and Weil pairing. In this protocol, the mutual authentication and anonymous authentication were realized, and the traffic analysis attack, impersonation attack and replay attack were resisted. Compared with the random Hash lock, Hash chain and New-Gen2, this protocol can resist most of the attacks which have been discovered.
    Graphics and image technology
    Supervised boundary detection for small sample problem
    GAO Liang LIAO Zhi-wu LIU Xiao-yun CHEN Wu-fan
    2011, 31(10):  2697-2701.  DOI: 10.3724/SP.J.1087.2011.02697
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    For natural images of complex texture, a supervised boundary detection method using the multi-information fusion was proposed. The texture information was introduced by quickly generating texton feature in the case of small sample. Intensity and texture gradients were further computed according to the differences of intensity and texton distributions within a pixel's neighborhood. In this way, a two-dimensional gradient feature vector was constructed, and a supervised classifier was used to adaptively detect original edge pixels. Finally, a boundary localization function was designed to determine the final edge pixels. The experimental results have demonstrated that the proposed method is faster and more effective.
    Harris corner detection algorithm based on adaptive fractional differential
    WANG Cheng-liang QIAO He-song CHEN Juan-juan
    2011, 31(10):  2702-2704.  DOI: 10.3724/SP.J.1087.2011.02702
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    False corners will emerge in the corner detection of the image with high texture complexity by Harris algorithm, and when fractional differential is applied to image processing, the order needs to be specified by human. This paper analyzed the reason that caused the false corners and suggested to replace the integral order in the algorithm with fractional order to operate differential coefficient so as to improve the algorithm. The paper also brought forward an approach regarding fractal dimension as a parameter which came from the order in choosing differential coefficient. So the marginal information of image can be saved when operating the differential coefficient of the image, and this approach makes the fractional differential be applied in occasions with high real-time requirements such as video target tracing and video image stabilization. The tests show that the modified algorithm has higher precision in the corner detection.
    Ellipse detection algorithm based on center extraction
    FAN Yi FU Ji-wu
    2011, 31(10):  2705-2707.  DOI: 10.3724/SP.J.1087.2011.02705
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    For the Hough transform method for ellipses detection is slow and needs huge storage, a fast randomized algorithm was presented. The algorithm randomly sampled two edge-points and searched for the third point to determine the center coordinate of an ellipse by the characteristics of pole chord, and then solved the elliptic systems obtained by coordinate transformation to get the rest parameters of the ellipse. At the time of determining a candidate ellipse by a verification process, only the points in the enclosing rectangle of the ellipse were selected. And the authenticity of a potential ellipse was confirmed by a special cumulative function. The experimental results demonstrate that the proposed method has the advantages of high speed and accuracy as well as strong resistance to partial occlusion.
    Contour connecting method based on interzone line
    ZHENG Li-ping LI Guang-yao JIANG Hua
    2011, 31(10):  2708-2710.  DOI: 10.3724/SP.J.1087.2011.02708
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    In order to reduce the number of triangular patches in surface rendering, save space and improve reconstruction results, a contour connecting method based on interzone line was proposed in this paper. This connecting method needed to resample with angle and generate secondary resampling points with geometric methods. And resampling points corresponded with each other. Tissue surfaces were reconstructed with quadrilateral patches and 3D reconstruction was realized. In experimental simulation, a series of head CT images were researched. The simulation analysis shows that to resample the contour line and use quadrilateral patches instead of triangular ones, the number of patches is reduced and the storage space is saved. The reconstruction time is short and the reconstruction efficiency is high.
    Image inpainting method based on structure tensor
    LIU Kui SU Ben-yue ZHAO Xiao-jing
    2011, 31(10):  2711-2713.  DOI: 10.3724/SP.J.1087.2011.02711
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    Because the traditional anisotropic diffusion equation for image restoration only considers the gradient size, and produces false edges in color image inpainting, this paper proposed an image inpainting method based on structure tensor. Structure tensor was used as diffusion coefficient which can implement different diffusion processes in different regions. The experimental results show that the new method, in comparison with Total Variation (TV) and BSCB methods, improves the image inpainting results, and effectively inpaints color images.
    Precise image reconstruction based on ROMP algorithm in compressive sensing
    LI Yun-hua
    2011, 31(10):  2714-2716.  DOI: 10.3724/SP.J.1087.2011.02714
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    The unsuitable iterative number of the Regularized Orthogonal Matching Pursuit (ROMP) algorithm in the framework of Compressive Sensing (CS) may reduce the quality of image reconstruction greatly. In this paper, an algorithm was proposed to determine the proper iterative number. In order to guarantee the quality of image reconstruction, the best iterative number of every image block with various sparsity was obtained by using the prior knowledge which resulted from last iteration. The experimental results show that the method can get better reconstruction performance than the ROMP algorithm with deterministic iterative number.
    Multi-resolution simplification algorithm for point cloud
    YANG Bin FAN Yuan-yuan WANG Ji-dong
    2011, 31(10):  2717-2720.  DOI: 10.3724/SP.J.1087.2011.02717
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    To efficiently simplify point cloud by multi-resolution, firstly, uniform grids were used to represent the spatial topology relationship of point cloud and calculate the k-nearest neighbors for each data point. Then normal vectors of data points were estimated by constructing covariance matrix, and normal vectors were directed to the outside of the point cloud. Finally, the formulation for measuring the importance of data point was achieved according the effect of this point on eigenvalues spectrum of the Laplace-Beltrami operator, and it was associated with the k-nearest neighbors of this point and normal vectors, and then multi-resolution simplification of point cloud was realized by changing the value of control factor. The experimental result shows that this algorithm has high simplification rate, fast speed, strong stability, and maitains the small detailed information of point cloud.
    Fast block-matching motion estimation algorithm based on directional adaptive sampling search
    WANG Qiang LI Yue-e
    2011, 31(10):  2721-2723.  DOI: 10.3724/SP.J.1087.2011.02721
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    In order to improve the searching accuracy of motion estimation, a new algorithm called Directional Adaptive Sampling Search (DASS) algorithm was proposed. According to the information of matching error in search patterns, the algorithm adopts two sorts of triangle search patterns adaptively. The strategy of local sampling search was employed for the sake of big-motion vector. Early termination strategy was adopted in the procedure of DASS so as to further speed up the search. The experimental results show that the proposed algorithm not only ensures the speed but also improves the accuracy of search with Peak Signal-to-Noise Ratio (PSNR) degradation of only 0.28dB on average.
    Facial feature point localization based on MR-AAM dual-fitting
    YE Chao LI Tian-rui GONG Xun
    2011, 31(10):  2724-2727.  DOI: 10.3724/SP.J.1087.2011.02724
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    The original inverse compositional Active Appearance Model (AAM) only does one fitting process. When the initial position is far away from the destination, the model often falls into local minimum and becomes hard to converge into the correct position. Against this problem, a dual fitting method using Multi-Resolution AAM (MR-AAM) was proposed. Firstly, the first time fitting was to locate the initial position of the face in the low-resolution AAM, and the second time fitting was to use inverse compositional algorithm in the high-resolution AAM. This method can find the exact initial position and achieve better result of facial feature point localization. The experimental results show that the proposed method performs better than traditional method in the fitting accuracy along with the real-time case.
    Single sample face recognition based on sample augment and improved 2DPCA
    ZHAO Ya-ying TAN Yan-qi MA Xiao-hu
    2011, 31(10):  2728-2730.  DOI: 10.3724/SP.J.1087.2011.02728
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    As most of the face recognition techniques will suffer serious performance drop when there is only one training sample per person, a face recognition algorithm based on sample augment methods and improved Two Dimensional Principal Component Analysis (2DPCA) was proposed. By analyzing the advantage and disadvantage of various sample augment methods, some of them were combined to synthesize virtual samples in order to make full use of the single training image. Improved 2DPCA was chosen to extract the feature of the synthetic virtual samples. The training samples were divided into sub-blocks and then the covariance matrix was constructed by these sub-blocks which were normalized by the within-class average value in each sub-block. The experimental results on ORL and Yale face database indicate that the performance of the proposed algorithm is better than those of general 2DPCA and the method only using sample augment.
    Anti-occlusion object tracking algorithm based on adaptive multiple cues fusion
    CAO Jie FU De-qiang
    2011, 31(10):  2731-2733.  DOI: 10.3724/SP.J.1087.2011.02731
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    Complex background, especially when the object is similar to the background in color or the target gets blocked, can easily lead to tracking failure. Therefore, a particle filter integrating color feature and texture feature was proposed. An object tracking algorithm based on adaptive multiple cues fusion was proposed too. When occlusion occurred, the fusion rules would be switched in time. Mean-shift algorithm was applied to each particle to overcome degeneracy. The experimental results show that this algorithm is robust to occlusion and is able to track object under complex background.
    Improved auto-focus algorithm of dual parameters estimation
    TANG Bo
    2011, 31(10):  2734-2737.  DOI: 10.3724/SP.J.1087.2011.02734
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    To figure out the phase error in the high-resolution Synthetic Aperture Radar (SAR) imaging caused by using traditional auto-focus algorithm in which only velocity is considered, the quality of SAR image was analyzed when errors of two parameters of Doppler rate exist. One method of estimating both velocity and the nearest distance of range was proposed, which was based on the mathematic model that was much closer to the real, and this method could estimate the nearest range better. Finally, the testing data verify the effectiveness and applicability of the algorithm in the high-resolution SAR imaging.
    Three-dimensional detection range of radar in complex environment
    ZHANG Jing-zhuo YUAN Xiu-jiu ZHAO Xue-jun MENG Hui-jun
    2011, 31(10):  2738-2741.  DOI: 10.3724/SP.J.1087.2011.02738
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    When building up the virtual battlefield system, to realize the three-dimensional (3D) detection range of radar in complex natural environment and complex environment of electronic interference, an improved support jamming model was proposed, according to the fundamental principle of Advanced Propagation Model (APM) and taking full consideration of the influence of electronic interference. This model mixed APM and electronic interference model together, and paid special attention to the refractive influence. Besides, this model could depict the double influence from complex natural and electronic interfering environments. Furthermore, a modified Marching Cube (MC) model, the triangles gained by MC being replaced by surface points and the interpolated points by middle points, was used to accelerate the process of visualization. According to the procedure of data gaining, data processing and data rendering, the 3D detection range of radar on specific electronic jamming environment was rendered via Visualization Toolkit (VTK).
    Fusion algorithm of remote sensing images based on wavelet packet and edge features
    ZENG Yu-yan HE Jian-nong
    2011, 31(10):  2742-2744.  DOI: 10.3724/SP.J.1087.2011.02742
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    To obtain more image details, a remote sensing image fusion algorithm based on edge features was proposed. It applied wavelet packet transform, and determined fusion rules according to the wavelet coefficients and edge features of three sub-direction bands. The experiments on TM multi-spectral image and SPOT high-resolution image were carried out, and the fusion results were analyzed from both subjective and objective perspectives. The simulation results show that this method has certain improvement in both performing dimensional detail information and maintaining spectral information.
    Path editing technique based on motion graphs
    DU Yu CHEN Zhi-hua XU Jun-jian
    2011, 31(10):  2745-2749.  DOI: 10.3724/SP.J.1087.2011.02745
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    This paper improved the algorithm of generating transitions and searching for path, and proposed a path editing method based on motion graphs. With regard to generating transitions, this paper detected the motion clips which can be used to blend automatically by minimizing the average frame distance between blending frames, and proposed Enhanced Dynamic Time Wrapping (EDTW) algorithm to solve this optimization problem. Concerning path search in the motion graph, this paper used the area between two curves as the target function and improved the strategy of incremental search and the strategy of branch and bound. The result shows that the proposed algorithm can edit and generate the character motions that well match the paths specified by users.
    Quality evaluation of halftone based on visual perception similarity
    ZHANG Han-bing
    2011, 31(10):  2750-2752.  DOI: 10.3724/SP.J.1087.2011.02750
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    To measure quality of halftones or halftoning algorithms, this paper proposed Mean Luminance Similarity Error (MLSE), Mean Contrast Similarity Error (MCSE) and Visual Perception Similarity Error (VPSE) to measure the visual perception similarity between halftones and their original continuous-tone images. In the proposed method, an input image was divided into several blocks according to local adaptation of human eyes, and luminance similarity error and contrast similarity error in each block were computed according to luminance adaptation and contrast masking on visual perception. Finally, the MLSE, MCSE and VPSE were computed to evaluate luminance similarity, texture similarity and local unexpected artifacts respectively. The experimental results show that the proposed quality measures are more agreeable to HVS in comparison with Peak Signal to Noise Ratio (PSNR) and Weighted Signal to Noise Ratio (WSNR) in terms of luminance similarity and in comparison with Unique Quality Index (QUI) and Structure Similarity Index Measure (SSIM) in terms of texture similarity.
    Image segmentation based on grayscale iteration threshold pulse coupled neural network
    LI Hai-yan ZHANG Yu-feng SHI Xin-ling CHEN Jian-hua
    2011, 31(10):  2753-2756.  DOI: 10.3724/SP.J.1087.2011.02753
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    A new method, called Grayscale Iteration Threshold Pulse Coupled Neural Network (GIT-PCNN), was proposed for image segmentation. The GIT-PCNN reduced the required parameters of conventional PCNN and the exponentially decaying threshold was improved to be related to the grayscale statistics of the original image. When GIT-PCNN was applied to image segmentation, no parameter or iteration time needs to be determined since the segmentation could be completed by one time of PCNN firing process. Therefore, GIT-PCNN did not require specific rule as the iteration stop condition. GIT-PCNN made good use of the grayscale information of the original image and the pulse characteristics of PCNN that the neurons associated with each group of spatially connected pixels with similar intensities tended to pulse together when partitioning images. The experimental results show that GIT-PCNN is better than classical PCNN-based segmentation algorithms on visual evaluation, subjective indices and speed performance.
    Lesion area segmentation in leukoaraiosis's magnetic resonance image based on C-V model
    ZHENG Xing-hua YANG Yong ZHANG Wen ZHU Ying-jun XU Wei-dong LOU Min
    2011, 31(10):  2757-2759.  DOI: 10.3724/SP.J.1087.2011.02757
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    Concerning that the lesion areas of leukoaraiosis in Magnetic Resonance (MR) image present hyper intense signal on T2 flair sequence, a level set segmentation method based on C-V model was proposed. First, the C-V model was improved to avoid the re-initialization; second, the Otsu threshold method was used for image's pre-segmentation, and then the image's pre-segmentation result was directly used as the initial contour for the improved C-V model; finally, the segmentation result was obtained by curve evolution. The results show that the proposed segmentation method can get better separation effects, and realize fast auto-segmentation. It has certain application value for clinical diagnosis and prognosis on leukoaraiosis.
    Real-time scan conversion for ultrasound based on CUDA
    WANG Wei-min WANG He-chuang WANG Hua-jun
    2011, 31(10):  2760-2763.  DOI: 10.3724/SP.J.1087.2011.02760
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    Scan conversion is one of the most important and widely-used technologies in medical ultrasound imaging. Unfortunately, traditional scan conversion algorithm needs intensive computation, which becomes one of the performance bottlenecks of the ultrasound system. In order to overcome this shortcoming, three parallel algorithms called real-time scan conversion for ultrasound based on Compute Unified Device Architecture (CUDA) were proposed. Through assigning the best structure of threads, rationally arranging data transmission between Central Processing Unit (CPU) and Graphic Processing Unit (GPU), and dividing computing tasks, throughput of the algorithm was increased and real-time requirement was met. Finally, this paper compared the three types of real-time scan conversion algorithms on CUDA to traditional method. This paper gets a frame rate of about more than 746fps with the picture size of 3121×936, which is about 300 times faster than the CPU implementation.
    Online automated grading of pearl surface perfection based on computer vision
    XU Shu-chang QIU Xian ZHANG San-yuan
    2011, 31(10):  2764-2766.  DOI: 10.3724/SP.J.1087.2011.02764
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    An online automated grading system of pearl perfection based on computer vision was introduced to replace time-consuming human grading. Firstly, the whole pearl surface was captured as images when the pearl freely fell. The surface images were then analyzed in real-time to obtain valid features, and then the features were applied to determine the final pearl perfection grade. The performance shows the new system greatly improves the efficiency of pearl surface perfection grading and cuts the cost down as well.
    Efficient Blob analysis of binary image for defects inspection in optical films
    HU Guang-hua
    2011, 31(10):  2767-2769.  DOI: 10.3724/SP.J.1087.2011.02767
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    One of the key issues for a vision system used for the inspection of defects in optical films is the real-time performance request for image processing. A new Blob analysis algorithm based on Run-Length Encoding (RLE) for binary image was proposed, without any need to build an equivalence table or to unite equivalent labels. Since a dynamic step-by-step search method was adopted, each RLE needed to be scanned only once and did not need to be compared with all the RLEs at the upper line, which benefited a compressed search space. Quite limited branches were involved when analyzing RLE's connectivity, which simplified the process and improved the entire efficiency. With the specific data structure design, access of the header and the tail of a RLE list could be done directly, which made it efficient when handling labeling-conflict. The experimental results show that the proposed algorithm is robust and efficient. Moreover, a comparison of the computational results with the existing methods indicates that the proposed approach is a viable alternative for effectively labeling connected component. The algorithm has been successfully applied to a vision system for the inspection of defects in optical films.
    Artificial intelligence
    Self-organizing fuzzy neural network algorithm based on unscented particle filter
    CHENG Hong-bing NI Shi-hong HUANG Guo-rong LIU Hua-wei JIANG Zheng-yong
    2011, 31(10):  2770-2773.  DOI: 10.3724/SP.J.1087.2011.02770
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    In this paper, a Self-Organizing Fuzzy Neural Network (SOFNN) based on Unscented Particle Filter (UPF) was designed and developed. The UPF was used to estimate the parameters of the SOFNN and better result was gotten. The generating criterion of fuzzy rules based on the pruning strategy of the error reduction ratio was introduced. The width of membership function was established as the state and the ideal output as the measurement. The UPF was used to learn parameters. The two typical simulations, nonlinear function approximation and system identification, were done to validate the UPF-SOFNN. It can be seen from the results of simulation that the UPF-SOFNN has a more compact structure and better generalization than the other algorithms.
    Applications of molecular-kinetic-theory-based clustering approach on gene expression data
    LI Jun-lin FU Hong-guang
    2011, 31(10):  2774-2777.  DOI: 10.3724/SP.J.1087.2011.02774
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    In order to find possible diagnostic genes that may typically assist in disease diagnosis, clustering technologies are always used to analyze gene expression data. Molecular-kinetic-theory-based clustering approach is a new and effective clustering technique. It finds data clusters by following the molecular kinetic mechanism. This dynamic clustering approach does not require presetting the number of clusters and can be used to estimate the number of clusters. The authors applied the method on gene expression data to estimate the number of clusters and possible diagnostic genes according to relevant clustering criteria. The simulation results and analysis verify the good knowledge discovery ability of this approach.
    Outlier detection algorithm based on global nearest neighborhood
    HU Yun SHI Jun WANG Chong-jun LI Hui
    2011, 31(10):  2778-2781.  DOI: 10.3724/SP.J.1087.2011.02778
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    Traditional outlier detection algorithms fall short in efficiency for their holistic nearest neighboring search mechanism and need to be improved. This paper proposed a new outlier detection method using attribute reduction techniques which enabled the algorithm to focus its detecting scope only on the most meaningful attributes of the data space. Under the reduced set of attributes, a concept of neighborhood-based outlier factor was defined for the algorithm to judge data's abnormity. The combined strategy can reduce the searching complexity significantly and find more reasonable outliers in dataset. The results of experiments also demonstrate promising adaptability and effectiveness of the proposed approach.
    cTwigStack: Improved twig pattern matching algorithm
    YAO Quan-zhu GUO Zhen FANG Mei-jun
    2011, 31(10):  2782-2785.  DOI: 10.3724/SP.J.1087.2011.02782
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    How to quickly locate the interested information in the XML database under a certain twig pattern is a popular research topic. To solve the problem that the TwigStack algorithm for handling the case with parent-child nodes would come out with massive intermediate results, an improved twig pattern query algorithm of cTwigStack was proposed, which was based on caching the non-leaf nodes and delaying the leaf nodes output. The experimental results on Treebank dataset indicate that the proposed algorithm can achieve the most accurate results of the queries that contain the ancestor-descendant relationships below branching nodes. Besides, compared with the present algorithm, it is also highly effective when processing parent-child relationships below branching nodes.
    Denoising method of non-spherical distributed data set
    ZHANG Yan YAN De-qin ZHENG Hong-liang
    2011, 31(10):  2786-2789.  DOI: 10.3724/SP.J.1087.2011.02786
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    Considering the over-sensitiveness of traditional Support Vector Machine (SVM) to noises, and the excessive dependence on the geometric shape of sample set of Fuzzy SVM (FSVM), Rough Support Vector Machines based on Noise Filtering System (NFS-RSVM) was proposed. Firstly, the sample that was most likely to be noise was filtered out by Noise Filtering System (NFS); then the equivalence class which was implied in the data was integrated into the SVM model as a double punishment factor for distinguishing valid and noise samples. The simulation results on UCI show that NFS-RSVM can remove most of the noises effectively, and the accuracy is improved partly compared with the traditional SVM and FSVM. Therefore, NFS-RSVM shows better noise immunity, classification performance and generalization ability when dealing with the non-spherical distributed data set with too many noises.
    Flight data denoising method based on stationary wavelet transform
    LI Zheng-xin ZHANG Feng-ming ZHANG Xiao-feng FEI Wen
    2011, 31(10):  2790-2792.  DOI: 10.3724/SP.J.1087.2011.02790
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    In order to get rid of the noise of flight data more effectively, based on discussing the principle of Stationary Wavelet Transform (SWT), a new denoising method was proposed, which combined correlation of wavelet coefficient with wavelet shrinkage. Firstly, signals were decomposed by using SWT; secondly, wavelet coefficient was dealt with by using methods of coefficient correlation and wavelet shrinkage in sequence; at last, denoised signal was reconstructed through inverse wavelet transform. The results of experiments show that the proposed method can raise Signal-to-Noise Ratio (SNR), decrease Mean Squared Error (MSE) and preserve the shape of signal; and it can be applied to flight data effectively.
    Semi-supervised classification algorithm based on relative transformation
    YI Miao LIU Xiao-lan
    2011, 31(10):  2793-2795.  DOI: 10.3724/SP.J.1087.2011.02793
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    In order to enhance the ability of dealing with sparse and noisy data of graph-based semi-supervised learning algorithm Local and Global Consistency (LGC), a LGC algorithm based on relative transformation was proposed. The original data space was converted to the relative data space by the proposed algorithm. In the relative space, the noise and outliers would become further away from the normal points, and the sparse points would become relative closer, which can improve the performance of the LGC algorithm. The experimental results on several data sets show that the classification capability of the proposed algorithm for noisy and sparse data sets increases significantly.
    Improved particle swarm optimization based on dynamic random search technique and good-point set
    LIANG Xi-ming CHEN Fu LONG Wen
    2011, 31(10):  2796-2799.  DOI: 10.3724/SP.J.1087.2011.02796
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    In order to overcome the problems of poor local search and premature convergence on Particle Swarm Optimization (PSO) algorithm, an improved particle swarm optimization approach based on Dynamic Random Search Technique (DRST) and good-point set was proposed in this paper. DRST was introduced to optimize the current best position of the swarm. On the other hand, reinitialization with a good-point set manner was employed for the swarm falling into premature convergence to go out of the local optimum. Linear search in the negative gradient direction was also applied to accelerate the optimization. In the end, an experiment was given and the results show that the improved algorithm has rapid convergence, great ability of preventing premature convergence and better performance than Standard Particle Swarm Optimization (SPSO) and Dissipative Particle Swarm Optimization (DPSO).
    CBR-based emergency case ontology model
    ZHANG Xian-kun LIU Dong GAO Shan DU Lei
    2011, 31(10):  2800-2803.  DOI: 10.3724/SP.J.1087.2011.02800
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    In order to solve the semantic conflict of emergency cases understanding in Case-Based Reasoning (CBR), an emergency case ontology model based on CBR was defined on the basis of the extended ABC ontology model according to the analysis of emergency cases, and the key elements of the model were described in detail, such as concepts, relations, axioms and instances. Finally, the model was validated by the analysis on the case of the nuclear crises of the first nuclear power station in Fukushima.
    Design knowledge sharing platform based on functional ontology
    XIONG Jing LIU Yong XU Jian-liang
    2011, 31(10):  2804-2807.  DOI: 10.3724/SP.J.1087.2011.02804
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    To overcome the deficiency in sharing and reusing design knowledge in manufacturing industry, a strategy based on functional ontology was proposed for design knowledge-sharing. The existing product structure can be mapped to its product functions by using functional ontology, and the design principles can be represented by functional decomposition tree. First, the basic framework of functional ontology was introduced. Then, the role of the functional decomposition tree to product design was analyzed. Finally, a knowledge-sharing platform for household appliances was designed and developed based on functional ontology. It was used to verify the proposed strategy. The experimental results show that the proposed strategy can effectively realize information retrieval, sharing and reuse of design knowledge in manufacturing industry. It can also shorten product development cycles.
    Improvement of semantic distance-based concept similarity computation in Web service matching
    XU Hong-yan FANG Xin FENG Yong
    2011, 31(10):  2808-2810.  DOI: 10.3724/SP.J.1087.2011.02808
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    In Web service matching, the concept similarity computation based on semantic distance plays an important role. Because the influence of semantic asymmetry and semantic density has not been considered in current concept similarity computation based on semantic distance, the computation result is not accurate. To enhance the accuracy of the concept similarity computation, the semantic distance-based concept similarity computation was improved by adding the asymmetry factor and density factor on the basis of the current research. Finally, the feasibility of the improved semantic distance-based concept similarity computation was verified via an example. According to the contrast analysis, the improved semantic distance-based concept similarity computation can reflect semantic relationship between concepts more truly and the computation result is more in line with the objective reality.
    Shape recognition algorithm for ST-segment of ECG signal
    WANG Zhen-xing ZHANG Si-jie ZENG Xiao-ping
    2011, 31(10):  2811-2813.  DOI: 10.3724/SP.J.1087.2011.02811
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    Concerning the low accuracy and easily being interfered by noise of ECG diagnosis of ST-segment, a ST-segment detection algorithm based on least-square polynomial fitting was proposed. Firstly QRS complex was detected by dyadic spline wavelet through Mallat algorithm, then the characteristic points such as T wave, onset of QRS complex, J point, onset of T wave were detected. These characteristic points were used to judge the direction of ST-segment, and then the ST-segment was classified into line type and curve type, finally the slope of line type ST segment and concavo-convex direction of curve type ST-segment were determined through using polynomial fitting algorithm. This algorithm was certified by the simulation experiment on the signals of MIT-BIH database, and the accuracy of ST-segment shape recognition was more than 90%. The experimental results show that the algorithm reduces the noise interference of characteristic detection of ST-segment, and improves the accuracy of ST-segment detection.
    Applications of simulated annealing-immune particle swarm optimization in emotion recognition of galvanic skin response signal
    ZHOU Yu-ting LIU Guang-yuan LAI Xiang-wei
    2011, 31(10):  2814-2817.  DOI: 10.3724/SP.J.1087.2011.02814
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    An improved immune particle swarm optimization was presented in this study in order to increase the effectiveness of feature selection for emotion recognition based on Galvanic Skin Response (GSR). Firstly, 342 groups of GSR signal with each containing 6 kinds of affective data were denoised, and afterwards the original features were extracted. Then simulated annealing mechanism was introduced to the particle update process of Immune Particle Swarm Optimization (IPSO), and the Simulated Annealing-Immune Particle Swarm Optimization (SA-IPSO) was adopted for feature selection. The experimental results show that compared with IPSO, SA-IPSO can achieve relatively high recognition rate with fewer features, the application of simulated annealing mechanism can help with the optimization of feature selection, and the improved algorithm also performs well on global convergence.
    Preferable selection of offensive mine-laying plans for unmanned aerial vehicles based on set pair analysis
    DONG Wen-hong YI Bo LIN Qiang
    2011, 31(10):  2818-2820.  DOI: 10.3724/SP.J.1087.2011.02818
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    In order to solve the preferable selection problem of offensive mine-laying plans for unmanned aerial vehicles, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) based on connection number was adopted. With reference to the traditional essential factors for evaluation of mine-laying plans, the synthesized parameter of Unmanned Aerial Vehicle (UAV) was also selected as the main index to scale the effect of mine-laying platform. Then the connection number was used to describe the identity-contrary degree based on integrated plan, while the information entropy weight of each factor was calculated. For the reliability of the ranking process, the relative certainty probability power was improved with the stabilization coefficient, which could be used to evaluate and rank the mine-laying plans. The simulation results indicate the availability of this algorithm.
    Autonomous localization of mobile robot based on odometer and PTZ vision
    NIU Guo-chen XU Ping FENG Qi
    2011, 31(10):  2821-2824.  DOI: 10.3724/SP.J.1087.2011.02821
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    To reduce the influence of cumulative odometer localization error, an autonomous localization approach for mobile robot based on odometer and Pan-Tilt-Zoom (PTZ) vision was presented. Interrupt S-shaped searching strategy was put forward, as well as a vision localization approach based on finite automaton. The position credibility models of odometer and PTZ vision were established according to their positioning error sources. A localization framework combining odometer and PTZ vision based on real-time position credibility was designed. An application experiment of vision localization and localization using odometer and PTZ vision was carried out. The validity and practicability of the method are confirmed.
    Application of real-time analytic method in inverse kinematics of NAO model
    WANG Fan LI Long-shu
    2011, 31(10):  2825-2827.  DOI: 10.3724/SP.J.1087.2011.02825
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    In order to improve the accuracy and stability of the players in the movement of RoboCup3D simulation platform, a kind of real-time resolution of inverse kinematics for humanoid NAO model was proposed. Firstly, the lower limb topology of NAO model was analyzed, and its forward kinematics model was established. Secondly, the equations of every joint angle in all lower limbs were derived by real-time inverse kinematics analytic method. Finally, the algorithm was realized by coding. The experimental results validate the numerical stability and feasibility of online execution of the method, and the overall competitive level of the RoboCup3D simulation soccer team has been enhanced.
    Typical applications
    Workflow modeling and simulation for implementation stage of construction project based on Petri net
    LI Hai-ling SHI Ben-shan LIU Ke-jian
    2011, 31(10):  2828-2831.  DOI: 10.3724/SP.J.1087.2011.02828
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    In order to effectively carry out the workflow management and control, it is very important to build a workflow model which can accurately express the systematicness, dynamics and uncertainty during the implementation stage of a construction project. By analyzing the workflow features and building the workflow conceptual model of the implementation stage of construction project, the workflow model based on the hierarchical timed colored Petri net was presented. By means of the model, some items such as information flow, resource flow, exception handling, duration, and other abstract contents of the implementation stage can be available. It is not only providing a powerful methodology support for the workflow management and control, but also expanding the Petri net modeling in the field of construction engineering. With CPN Tools simulation platform, taking an example of the implementation stage of a general industrial and civil building, the authors built its workflow model for control and management, and at last, verified the correctness and effectiveness of the model.
    Multi-dimensional submodel and open integrated framework for energy consumption system of process industry
    MA Fu-min ZHANG Teng-fei
    2011, 31(10):  2832-2836.  DOI: 10.3724/SP.J.1087.2011.02832
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    Due to the various component factors and complicated structure, the simple model is unable to describe each aspect and different elements of energy consumption system for process industry globally and clearly, the multi-dimensional submodels and integrated method for energy consumption system of process industry were proposed. Integrating energy, information and personnel etc., the multi-dimensional submodels of energy consumption system were established from three perspectives about static structure description, dynamic energy-consuming behaviour and system operating destination. After analyzing the correlative relationship between different dimension submodels, the open integrated framework of multi-dimensional submodels of energy consumption system was presented in detail. The research results provide supporting method to establish multi-dimensional integration model for process industy energy consumption system combing with information flow, energy flow and material flow. This multi-dimensional integration model will make a good foundation for comprehensive energy efficiency evaluation of process industry.
    Multi-manufacturers-to-multi-supppliers order allocation model based on production load equilibrium
    SONG Fa-shuai XIANG Wei YE Fei-fan
    2011, 31(10):  2837-2840.  DOI: 10.3724/SP.J.1087.2011.02837
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    For the order allocation problem of industry cluster with multiple manufacturers and multiple suppliers, considering the suppliers' current available manufacturing resources, an order allocation model for supply chain with multi-suppliers to multi-manufacturers based on production load equilibrium strategy was proposed in this paper. The simulation case study of an industry cluster of injection molding parts manufacturers was used to verify that the model can not only narrow the supplier's production load fluctuation, but also can balance suppliers' production load in each cycle. The production load equilibrium strategy can not only guarantee the order's lead time, but also the equilibrium utilization of the suppliers' manufacturing resources, leads to promote the whole supplier group's operation level and efficiency and to realize the optimization of the entire supply chain.
    Blue-green algae bloom forecast platform with Internet of things
    YANG Hong-wei WU Ting-feng ZHANG Wei-yi LI Wei
    2011, 31(10):  2841-2843.  DOI: 10.3724/SP.J.1087.2011.02841
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    To overcome the shortcomings of conventional algal bloom forecast system in acquiring data, this study applied the Internet of Things (IoT) technology to establish a data transmission network with three-layer structure, and thus secured data continuity. With improved retrieval approach of water quality parameters, technology of Wireless Sensor Network (WSN) and forecast model of algal bloom, the blue-green algal bloom forecast platform was developed. The evaluation demonstrates that the platform achieves an overall accuracy of 80% in forecasting blue-green blooms in Taihu Lake in next three days.
    Early-warning model of logistics transport based on fuzzy comprehensive evaluation
    YANG Ying-xin FENG Zhi-yong RAO Guo-zheng SHI Hong
    2011, 31(10):  2844-2848.  DOI: 10.3724/SP.J.1087.2011.02844
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    Concerning the security issues in the current road transport logistics, an early-warning model of road transport logistics was proposed. First, five influence aspects of road transport logistics were discussed, including people, vehicles, roads, environment and carried goods. Then the early-warning indexes and the weight of each index were determined using the Analytic Hierarchy Process (AHP) and the expert scoring method. Finally, based on the multi-level Fuzzy Comprehensive Evaluation (FCE) method, the early-warning model of road transport logistics was constructed by selecting proper fuzzy operators. With the model, the early-warning information of road transport logistics could be obtained by calculating the early-warning level. The experiment shows that constructing the early-warning model of logistics transport by FCE is feasible. It realizes the early-warning in the transport process.
    Construction and application of quality evaluation system of GIS vector data normative mapping
    CAO Jun LIAO Shun-bao
    2011, 31(10):  2849-2852.  DOI: 10.3724/SP.J.1087.2011.02849
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    Regarding the existing normative data quality issues of the national land use/cover at scale of 1 to 250000 as the research object, the open source Geographical Information System (GIS) software was used to build a normative quality evaluation system that had characteristics of simple operation, objective evaluation and comprehensive inspection. This quality inspection system is a new rules-based quality evaluation system. According to different data quality issues, it flexibly designed quality inspection rules, and effectively integrated into the system. The experimental results show that the system can flexibly and efficiently check out the land use/cover normative data quality issues, and give an objective evaluation.
    Application of data warehouse technology in energy management of urban public buildings
    LUO Xian-xian
    2011, 31(10):  2853-2857.  DOI: 10.3724/SP.J.1087.2011.02853
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    Currently, many urban public building energy consumption monitoring systems have collected a large amount of building energy consumption data. Because these data sources are independent and scattered of each other, they cannot provide the environment of global data analysis, and they cannot effectively support the assessment of building energy consumption and the research of building energy-saving. A solution that applied the data warehouse technology to the energy consumption monitoring system of urban public buildings was proposed. Through the research of building energy consumption monitoring system and the investigation of the demand of application in the buildings' energy management, the multi-dimensional data model of the energy consumption data warehouse of urban public buildings was established. The theme design, index design and dimensional model design were studied. The instance of a college public buildings' energy consumption data warehouse was successfully built in the experimental phase. The result indicates that the solution can effectively provide good environment of data analysis for the management and decision-making of buildings' energy consumption.
    Real-time inspection and control system for six DOF platform based on INtime
    HUANG Mang-mang ZHOU Xiao-jun WEI Yan-ding
    2011, 31(10):  2858-2860.  DOI: 10.3724/SP.J.1087.2011.02858
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    As for six Degree Of Freedom (DOF) platform, its inspection and control system should not only meet the requirement for real-time control, but also has powerful graphic interface. Because of the disadvantages of the existing system, this paper designed a real-time inspection and control system which can meet both requirements in an industrial computer based on INtime. In this system, the method of direct operating on data acquisition and control cards was adopted by INtime process, to obtain real-time performance; in the meantime, nonreal-time tasks were handled by Windows process. The test results of real running demonstrate that the system has high real-time performance, and the animation of platform in user interface is rendered fluently, and verifies the feasibility and effectiveness of the system.
    Customization of validation rule based on NXOpen
    HUA Feng
    2011, 31(10):  2861-2864.  DOI: 10.3724/SP.J.1087.2011.02861
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    Concerning the problem that Knowledge Fusion (KF) functions have no comprehensive functionalities, which has affected the validation rule customization, this paper presented a method of customizing Check-Mate validation rules based on the NXOpen secondary development technology. It gave a survey on the NXOpen application programming interfaces, introduced the method how to use NXOpen to implement validation logic, and how to use the programming languages, C++, C#, VB .NET, and Java respectively to build the program library of validation rules, and how to use KF to wrap the functions in the program library to get KF functions with a uniform interface. It built the validation rule classes using NXOpen secondary development technology, and calling the customization validation rules, and thereby promoted the capacity to build validation rule knowledge library, and helped to enhance the application of the product design standard.
    Scoring system for training simulator of military power
    MENG Fei-xiang CHENG Pei-yuan YANG Xu-feng
    2011, 31(10):  2865-2868.  DOI: 10.3724/SP.J.1087.2011.02865
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    Most training simulators of military power cannot give reasonable evaluation to the operation process of soldiers, because of being lack of scoring system. Therefore, in this paper, the scoring system for training simulator of military power based on the operating rule of actually weapon and the knowledge of large-scale system theory and expert system was analyzed. The operating rule of the military power and the key technologies of scoring system such as building up scoring rule, selecting scoring standard, selecting coefficient for the score deductions, calculation of the scoring system and program process of the scoring system were deeply analyzed in this paper. At last, a very useful scoring system for the training simulator of gas turbine generator was developed.
    Independent online fusion algorithm for multi-sensor data
    ZHANG Jian-ye WANG Zhan-lei ZHANG Peng DU Ji-yong
    2011, 31(10):  2869-2871.  DOI: 10.3724/SP.J.1087.2011.02869
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    In the case that any prior knowledge was unknown, a new fusion algorithm was proposed in order to deal with the defect of the existing algorithm. In the algorithm, for better fusion accuracy, the mean and entropy based on multi-sensor support degree were used to excavate the redundant information sufficiently, and then the weight coefficient of sensor could be determined. In addition, a limited memory fusion was used to avoid data saturation when the old measurement information was increasing, and ensured delicacy degree when the measurement was changing. To verify the effectiveness of this algorithm, three algorithms were used to detect the sample data. The simulation result shows the weight distribution gained through the new algorithm is more effective, and the accuracy of fusion can be further improved.
    Arrival direction estimation of wideband linear frequency modulation signal based on DPT
    GAO Chun-xia ZHANG Tian-qi JIN Xiang BAI Juan
    2011, 31(10):  2872-2875.  DOI: 10.3724/SP.J.1087.2011.02872
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    To deal with broadband signal processing, a new algorithm for the Direction Of Arrival (DOA) estimation of wideband Linear Frequency Modulation (LFM) signal was introduced. In this paper, the broadband LFM signal was transformed into a narrowband signal by Discrete Polynomial-phase Transform (DPT). After that, the wideband LFM signal could be transformed into a single sinusoidal signal and the new noise. And the time-varying direction vector in time domain was changed to the time-invariant vector. Then, the conventional narrow band signal processing method, Multiple Signal Classification (MUSIC) algorithm, was used to estimate the DOA. The theoretical analysis and simulation results show that the proposed method can accurately estimate DOA of the signal. The scheme is easy to implement with less computation, and it has good estimation performance.
    Analysis of arrival time localization using kernel locality preserving projection
    ZHANG Yong-qiang ZHAO Chun-yan
    2011, 31(10):  2876-2879.  DOI: 10.3724/SP.J.1087.2011.02876
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    This paper aims at reducing the influence of ranging error on localization accuracy. A Wireless Sensor Network (WSN) localization algorithm was proposed, which was based on Kernel Locality Preserving Projection (KLPP). The algorithm took transmission time vector between nodes as input, and a model was established by KLPP, which can reflect partial information network topology structure. The simulation results indicate that compared with Kernel Principle Component Analysis (KPCA), the algorithm can achieve higher localization accuracy in Time of Arrival (TOA) localization and reduce the influence of ranging error on localization accuracy effectively in complex environment.
    Improvement of dynamic multi-objective evolutionary and orthogonal test for four-branch satellite antenna
    GUO Jin-cui ZOU Jin-xin SUN Peng-hui ZHUANG Yan
    2011, 31(10):  2880-2882.  DOI: 10.3724/SP.J.1087.2011.02880
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    A satellite antenna characterized by wide-beam, wide-bandwidth and microwave right-hand-circular polarization was designed. First, the Dynamic Dominant Evolution Algorithm (DDEA) was used to search globally on a parallel computing platform. Then orthogonal design and HFSS software based on finite element method were used to search within local scope evenly and elaborately, so that the antenna gain was further improved. The improved antenna meets the requirements on beam and saves the feeding power of satellite.
2024 Vol.44 No.4

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