Table of Content

01 October 2009, Volume 29 Issue 10

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Network and communications

DAMCC: Improved multi-rate multicast congestion control protocol

2009, 29(10):  2599-2602. 

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A new Dynamic Allocation bandwidth strategy for Multicast Congestion Control (DAMCC) was put forward. Concerning the current problems of adjusting the rate of granularity roughly and inadequate application about the Receiver-driven Layered Congestion control (RLC), this strategy designed an algorithm, which can calculate the rate of the enhancement layer dynamically and separately. The receiver of the strategy of DAMCC can calculate the value of the RoundTrip Time (RTT) according to the feedback response information, then calculate its own TCP friendly rate and receive the multicast data at the corresponding rate to achieve sharing the network resources with TCP flow fairly. The simulation results show DAMCC strategy can use network bandwidth more effectively than the RLC strategy, and it also solves the problem of network bandwidth heterogeneity. Besides, it can calculate the TCP friendly rate at the receiver to achieve sharing the network resources with the TCP flow fairly.

Trust model for mobile P2P network

2009, 29(10):  2603-2605. 

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Since the mobile P2P network is characterized by large-scale distribution and high dynamics, a trust model based on dynamic feedback mechanism was proposed. Two new parameters, distance factor and recommend factor, were introduced to control the size of chain of recommended trust, so as to improve the veracity of recommend trust. In addition, the feedback mechanism and punishment mechanism were integrated into the calculation of the recent trust and long-term trust, so the trust model has better adaptability to the dynamics of trust. Simulation experiments show that the model has very good dynamic adaptability and is able to effectively isolate the malicious node.

Decentralized fair multi-party exchange protocol under P2P environment

2009, 29(10):  2606-2610. 

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The multi-party exchange of valuable digital resources in P2P environment has some problem on resources certification and objects exchange. A decentralized fair multi-party exchange protocol was proposed. The protocol adopted cross-validation theory to identify recourses and solved the problem of the negotiation among multi-party exchanges in term of one-way release mechanism and the new one-way exchange mesh structure. Meanwhile, the protocol certificated its own fairness on the basis of right cross validation.

Topology control of wireless network based on different transceiver gains

2009, 29(10):  2611-2613. 

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The topology control optimizes wireless networks by adjusting nodes transmission power or other performance index. Meanwhile, nodes in heterogeneous wireless network possess different features, which obstructs the optimization of wireless network with the traditional topology control algorithms developed from homogeneous networks. This paper proposed a kind of topology control model by introducing SINR into topology model, in order to solve the interference caused by nodes different transceiver gains. By adopting hierarchical clustering algorithm, new topology control strategy could improve the performance of heterogeneous wireless networks, which is supported by simulations.

Performance of STBC-OFDM system in 3GPP channel model

2009, 29(10):  2614-2616. 

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STBC-OFDM-combined Space Time Block Code (STBC) and Orthogonality Frequency Division Multplexing (OFDM) technology, may be effective against multi-path effect and frequency selective fading. It can improve transmission efficiency and reduce error rate, and has simple encoding and decoding. In this paper, the authors used Matlab to build system simulation platform, simulated its transmission process in 3GPP channel, chose parameters of simulation system, and evaluated bit error performance according to different channel environment.

Research of task execution time based on host load

2009, 29(10):  2617-2619. 

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In the grid computing, the prediction of the dynamic change of network node performance and the implementation of the grid task is one of the most important factors, which decides whether the efficient scheduling of grid task will be successful. In this dissertation, the authors studied and analyzed an algorithm predicting the execution time of task by the linear relationship between host load and the execution time of task. Then the authors simulated the prediction algorithm about the task execution time, validated the reliability of the execution time prediction of the task based on host load, and evaluated its prediction precision.

Data scheduling model based on incentive for P2P media streaming

2009, 29(10):  2620-2623. 

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In order to solve the unfairness in the existing algorithm on data scheduling in P2P media streaming, a new algorithm model having incentive function was proposed. It can dynamically adjust bandwidth allocation of peers according to their packet loss and contribution rate to realize maximum of receiving peers interests rationally and fairness of the whole system, and enhance system transmission efficiency. The simulation results show that this algorithm model motivates peers to participate in data scheduling and maintains system fairness.

Comparison of objective weight determination methods in network performance evaluation

2009, 29(10):  2624-2626. 

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The methods of standard deviations, maximizing deviations, entropy weight and their improved methods were applied to solve the objective weight determination problem of multivariate indexes in performance evaluation. It made the weight determination selection more comprehensive. The conflict of the indexes was introduced to take account of the correlation between indexes. The case study was implemented in VOIP network. The samples used to compute weights were obtained by simulation. Six weight computing methods were compared for selecting more objective weight determination method. The results show that Criteria Importance Through Intercriteria Correlation （CRITIC） method can get better objective weights.

Study on minimum hop routing in wireless sensor networks simulation

2009, 29(10):  2627-2631. 

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In order to improve the general performance of Minimum Hop Routing (MHR) wireless sensor networks, with the help of simulation, this paper revealed the shortcomings of traditional MHR wireless sensor networks, dug out the required information at low expenses to improve the traditional MHR wireless sensor networks, discussed the improving policies，and compared the performances of the networks before and after. The theoretical analysis and simulation results imply that it will improve the data transmission reliability, energy-efficiency and general performance if we revise the traditional MHR wireless sensor networks by the information derived from network behaviors with low cost.

Analysis of performance optimization on QoS-MSR routing applied to SWAN model

2009, 29(10):  2632-2634. 

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Routing protocol plays an important role in the supports of QoS such as reliability and stability in the Stateless Wireless Ad Hoc Networks (SWAN) model for Ad Hoc networks. In this paper, a new protocol named Quality of Service-Multipath Source Routing (QoS-MSR) multi-path routing was introduced into the SWAN model. It can effectively improve the quality of service by making the use of the two significant advantages of QoS-MSR that it can not only attach the information of QoS in the routing search process, but also adopt the algorithm of Multiple Bandwidth Splitting Reservation (MBSR). Simulation results indicate that the performance parameters of the network (end-to-end delay, throughput and the rates of data receiving) based on the adopted QoS-MSR in the SWAN model are remarkably improved.

Grid resource scheduling based on load control

2009, 29(10):  2635-2637. 

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Concerning the load system management of grid, this paper described grid model as an undirected graph (i-DG) by computing nodes connected by a set of communicating edges. Therefore, the authors presented the load measurement methods of node and communication, and brought forward how to get the load threshold and grid system load grade. By the load threshold, scheduler selected the resource whose node load was under the threshold and that communication load allowed; at the same time, the grid system load grade decided a resource request to be refused or accepted. As the requirement, the authors proposed the load management architecture, analyzed refresh periods of load threshold and grid system load grade. At last, the load management scheduling algorithm was described based on the load threshold and grid system load grade. Finally simulations were performed to compare the performance of load management scheduling algorithm with that of the None Minimisation. The experiments show that the load management scheduling algorithm is efficient and robust in controlling failed scheduling ratio and improving the throughput within grid environments, thus it is especially fit for overload.

Performance analysis of IEEE 802.11 multirate networks with rate adaptation

2009, 29(10):  2638-2643. 

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The discrete-time Markov chain model for the Automatic Rate Fallback (ARF) rate adaptation algorithm was proposed to analyze the performance of IEEE 802.11 ARF-based multirate networks. In the analytical model, the ability to differentiate the frame losses caused by link errors from those caused by collisions according to the choice of transmission modes between Basic and RTS/CTS was taken into consideration. By exploiting the model, the probability of transmitting with a specific data rate in stationary state was obtained for the case where a node chose the transmission mode with a random probability. Furthermore, the system throughput analysis was made with reference to the backoff mechanism. Simulation results show that the proposed model analysis could well predict the performance of multirate networks. In addition, the influence of the parameter settings of both ARF and MAC protocol on the network performance was investigated.

Research and realization of network security monitoring algorithm based on hypothesis verification model

2009, 29(10):  2644-2646. 

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To overcome the disadvantage of traditional network security monitor system, this paper introduced a new definition—network performance (NP) which can describe the status of network. Calculate the distributing parameter in the security network environment was calculated, and the amount of NP during the monitoring time was collected, then whether the network is secure was estimated by using hypothesis verification. At last, the result of experiment shows the new algorithm can reduce the network burthen, and increase the accuracy of network security estimation.

PCP: P2P-based computing resource sharing and aggregation platform

Hui Yu

2009, 29(10):  2647-2651. 

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A P2P-based computing resource sharing and aggregation platform called PCP was developed and constructed in this paper. PCP is a platform harnessing the immense computational resources available in the Internet for parallel and distributed computing. PCP platform is peer-to-peer based, easy to use and efficient. These features are strongly supported by a network overlay over which peers can communicate with each other. The authors made use of a general-purpose P2P library, JXTA, supporting the common requirements of P2P software, including network overlay. Other features of the P2P library, such as Ad Hoc self-organization, discovery and grouping of peers, also support PCP efficiently. A parallel programming library was also presented in PCP by JXTA communicating library. A volunteer node can submit and monitor the parallel applications by job management subsystem to complete the whole computation. The results obtained from performance analysis show that the throughput and speedup ratio of PCP are better in master-slave style parallel applications.

Research and improvement of streaming media system based on Gossip protocol

2009, 29(10):  2652-2654. 

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The Gossip-based P2P streaming media system has become the mainstream of P2P streaming media systems. But the inherent drawbacks of Gossip protocol—the randomness and uncertainties of data dissemination influence the P2P streaming media system. Based on the Gossip, an approach combining unstructured and structured P2P network was proposed to cover the shortage of the data dissemination based on Gossip and improve the efficiency of streaming media system. Finally the approach has been proved to be reliable through simulation.

Design and implementation of enterprise instant messaging system of cross-protocol

2009, 29(10):  2655-2658. 

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The environment of enterprise instant messaging application becomes more complicated due to constant amplification of its scale, increasing complexity of its organizational structure and diversity of objects of its interactive information, which poses a severe challenge to the existing enterprise instant messaging platform. Under such background, this paper presented the concept of enterprise instant messaging system of cross-protocol which was based on Extensible Messaging and Presence Protocol (XMPP). This paper outlined the development of enterprise instant messaging, introduced XMPP and gave detailed design and implementation of the system, providing enterprise with a good real-time information exchange platform and enhancing enterprise instant messaging reliability, stability and efficiency.

Graphics and image processing

Noise estimation for Cramer-Rao Bound analysis of multi-scale matching

2009, 29(10):  2659-2661. 

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The Cramer-Rao Bound (CRB) analysis can be used in the transform parameters estimation of multi-scale object matching, and the noise estimation is of crucial importance since the CRB is very sensitive to the input noise. A group of high pass digital filters were constructed by several finite difference operators with different orders, and the image was processed with these operators and the variance was estimated separately from the filtered data with Inter-Quartile Range (IQR) method. Then, by median filter concept, noise variance was approximated by the median of the estimated variances. The supposed approach to noise estimation is simple and effective, which has been verified by the experiments.

Face recognition based on feature level fusion

2009, 29(10):  2662-2664. 

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In order to search for an efficient feature extraction approach for face recognition, a method based on feature level fusion was presented. This method integrated Locality Preserving Projection (LPP) with Maximum Margin Criterion (MMC). Firstly, LPP was performed on training samples set, so the projection of each training sample on LPP subspace could be got. Further, MMC algorithm was performed on all the obtained projections to get more efficient discriminant features for recognition. Nearest Neighborhood (NN) algorithm was used to construct classifiers. The experiments on the ORL face database show that the recognition rate of the proposed method is high when pose, illumination condition, face expression and training sample number change.

New image denoising method based on Curvelet transform

2009, 29(10):  2665-2667. 

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The comparison between wavelet transform and Curvelet transform indicates that wavelet transform only has dot singularity and Curvelet transform has advantage of multi-scale singularity in each direction. After analyzing the method of image denoising by Curvelet transform, the paper proposed a new method of combining wrapping and cycle spinning Curvelet transform to improve the existing algorithm. According to the simulation experiment, the results of the denoised pictures show that the improved algorithm has reduced the pseudo-Gibbs phenomena, can reserve more detailed information, texture of images and get higher visual impression and PSNR value.

Image segmentation using iterative watershed and ridge detection

2009, 29(10):  2668-2670. 

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Those objects without regular boundaries and homogeneous intensities, such as metallographic images, make the conventional approaches hard to achieve a satisfactory partition. Therefore, a novel segmentation algorithm—an improved approach based on iterative watershed was presented. The seeds were selected by an effective double threshold approach, and the ridges were superimposed as the highest waterlines in the watershed transform. To tackle the over-segmentation problem, the blobs were merged iteratively with the utilization of Bayes classification rule. Experimental results show that the algorithm is effective in performing segmentation without too much parameter tuning.

Intersection method for triangular mesh model based on space division

2009, 29(10):  2671-2673. 

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The intersection problem between triangular mesh models is one of the key issues in the field of CAD/CAM. The authors analyzed the advantages and disadvantages of the existing space division technology and bounding boxes method, and then proposed an improved space division algorithm. This method can more precisely locate space grids that the triangular facets occupy. As a result, it decreases the number of triangular facets that need intersecting calculation. Experiments show that the new method can improve the efficiency of computing triangular mesh intersections based on space division.

Noise variance estimation based on inter-scale correlation of image coefficient of wavelet transform

2009, 29(10):  2674-2677. 

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Variance estimation is a common problem in noised image processing. The basic idea is to get a sub-image that includes only "pure" noise to estimate the variance of original noise. The traditional way is to obtain the sub-image by sampling the noised image in spatial or frequency domain, then calculate its variance to replace that of the original noise. It has some requirement on the distribution of the image information. Based on the traditional frequency sampling method, a new method was proposed. Firstly, choose the first effective oblique high sub-image in wavelet transform domain as the sub-noise image. Then wipe off the useful image information in it by using the inter-scale correlation of wavelet coefficient to get more "pure" noise sub-image and estimate its variance. Experiments of simulation and real 4f system show that the new method is more accurate than the traditional one. It is more suitable for the images from low-pass bandwidth system or images full of details.

Mean-Shift object tracking based on scale invariant feature transform

2009, 29(10):  2678-2680. 

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Mean-Shift algorithm performs well in object tracking field because of its advantages of fast pattern matching and non-parametric estimation. However, this algorithm has its inherent deficiencies. In order to improve the robustness of Mean-Shift algorithm, the target was divided into a number of sub-regions in this paper, each sub-region individually used Mean-Shift tracking, and those whose iterations are more than eight times quit. And Scale Invariant Feature Transform (SIFT) was employed to exclude those sub-regions with smaller matching key points. Finally, the object location was obtained according to the sub-regions with more matching key points. Experiments show that the proposed method is of high robustness in situations of occlusion, scale change, rotation, scene change, etc.

Image scrambling algorithm based on Logistic chaotic sequence and bit exchange

2009, 29(10):  2681-2683. 

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Based on the analysis of the defect of the traditional iterated image scrambling, a new image scrambling algorithm was proposed based on chaotic sequence and bit exchange. According to the pixel location, the algorithm changed the image pixel values by using XOR operation in different Logistic chaotic sequence and the binary sequences of pixel value. Without iteration, the algorithm used the self-relativity of image to encrypt image. Experimental data and results show that the algorithm can achieve more effective image scrambling compared with the traditional algorithm. The algorithm has good performance in resisting the salt pepper and cutting attack. Compared with the iterative types scrambling methods, it has higher efficiency too.

Intensity-based Consistent Elastic Registration Algorithms

2009, 29(10):  2684-2686. 

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In various medical image registration algorithms, intensity-based elastic registration has the advantage of automation of high degree, but the ambiguity in intensity correspondence in the algorithms may lead to mis-registration. The consistency registration algorithm, which used local cross correlation coefficient as the similarity metric, was proposed. The algorithm connects the forward and inverse transformations together and uses the sum of local cross correlation as similarity metric function. By adding a consistent constraint to the similarity metric, the method guarantees that forward and inverse transformations are mutually reversible. Additionally, the intensity correspondence is highly improved.

Moving shadow detection method based on PCA

2009, 29(10):  2687-2689. 

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Moving cast shadows generally exist in video sequence. To prevent moving shadows being misclassified as moving objects or parts of moving objects, and improve the accuracy of shadows detection algorithm, an algorithm of moving cast shadows was proposed based on spatial information. First, an adaptive background was generated by building Gaussian mixture background model, and the feature was extracted using Principal Component Analysis (PCA) based on transformation. Then, the moving cast shadows were detected utilizing the space coordination of shadow and object pixels. Experimental results show that the proposed algorithm is robust to noise, and can relieve the influence of illumination change and detect moving shadows correctly.

Dense stereo matching by region growing based on disparity space sampling

2009, 29(10):  2690-2692. 

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Through the research of the existing region growing method, the authors presented an improved algorithm, which was unlike the existing region growing algorithm that depended on the accuracy of the seeds. The algorithm can continue growing on the smooth region and repetitive patterns region. Firstly, obtain the initial set of seeds in the disparity space by matching the Harris points. Then build the newly growing method in the disparity space. The results demonstrate it can trace out the disparity space. In the growing process, it can rectify the wrong matching automatically, and guarantee matching accuracy and correctness in the smooth and repetitive pattern region.

Image mosaic via improved Levenberg-Marquardt algorithm

2009, 29(10):  2693-2694. 

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The improved Levenberg-Marquardt (LM) algorithm for image mosaic was presented. The evaluation factor was designed, which not only avoided the singular matrix problem of the computation but also made the error energy function decline more than the classical LM algorithm. The algorithm avoided the ineffective computation, and its globally convergent property has better effect on removing the ghosting phenomenon. The experimental result indicates that the image equality is improved significantly compared with that classical LM algorithm.

Hybrid optimization of SA-GA depth map extraction base on second-order prior model

2009, 29(10):  2695-2697. 

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This work deals with the depth information estimation of 3-D surface in a series of images from different shot angle. The proposed method used a new second-order prior model to model the smooth 3D surface information which cause intractable (non-submodular) optimization problems; improved optimization efficiency by using the hybrid optimization strategy of Simulated Annealing (SA) algorithm and Genetic Algorithm (GA). Experimental results demonstrate that the second-order prior model is a better model of typical scenes than the first-order prior one and the performance of the hybrid algorithm outperforms SA and GA alone.

Medical images fusion method based on revised wavelet transform

2009, 29(10):  2698-2699. 

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There are many applications of wavelet transform to image fusion. But the images fusioned usually are thermal or visible images. A multi-resolution fusion method based on morphology wavelet and a weighted fusion method based on difference image segmentation in wavelet region for medical images were proposed. These methods maintained the visual effect of wavelet, reduced the computation complexity to a great extent, and optimized the computation of weighted coefficients. The experimental results show the excellent fusion effect by these methods.

Advertisement effect evaluation system based on face detection and tracking

2009, 29(10):  2700-2702. 

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Various advertisements in public are important for commodities promotion, but its still hard to automatically analyze the effect. This paper presented a digital video processing based evaluation system, which captured the scene in front of the advertisement, then performed statistics on the number of the passengers, especially the ones looking to the advertisements, recorded their watching time intervals. With the above parameters, one could estimate the effect of the advertisements. Face detection adopted AdaBoost classifiers and face tracking used particle filters. The detection and the tracking are supplementary and could improve the tracking reliability. The experiments proved the effectiveness.

Binary factorization compression and Consensus algorithm

2009, 29(10):  2703-2705. 

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In graphics, Sigular Value Decomposition (SVD) is a popular method that has been used for compressing high dimensional data. Binary factorization is a simplified variant of SVD. There are two methods for binary factorization compression: the iterative heuristic and greedy algorithm. However, both of them are not very favorable in applications. The iterative heuristic does not guarantee the convergence in most cases and greedy algorithm cannot fit the need of large-scale matrices factorization. In this paper a new method was used for binary factorization compression: Consensus algorithm. Consensus algorithm is a brand-new approach to enumerating all the maximal bicliques for a given graph, which is proved to be an NP-complete problem and can give the solution in incremental polynomial time. For some bipartite graphs, the time complexity is polynomial. Experiments show that when the iterative heuristic does not work, consensus algorithm is a good method for binary factorization and ensures the stability.

Performance study of remote sensing image transmission system based on CCSDS

2009, 29(10):  2706-2709. 

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A new remote sensing image transmission scheme was presented in this paper. Firstly, the scheme united the bitstream service in CCSDS AOS recommendation with Go-Back-N (GBN) ARQ scheme, and transmitted the image in part, in order to solve the problem that the quality of the restructured image goes down caused by the high Bit Error Rate (BER) of star-to-ground communications. Secondly, analyzing the throughput of image transmission system in different length of data unit, a calculation method of optimum data unit length was proposed. Simulation results show the quality of the restructured image would go down when the BER increass, but in the stated BER (<10－4), the higher Peak Signalto Noise Ratio (PSNR) can be achieved, and the of restructured image is satisfactory.

Human face shape classification method based on active shape model

2009, 29(10):  2710-2712. 

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To improve the recognition rate and speed on huge face database, automatic face shape classification has attracted more and more attention. Human face shape can be classified into several categories: round face, elliptic face, square face, triangle face, etc. This paper proposed a novel method to classify human face shape automatically based on Active Shape Model (ASM). First, face images of different shapes were trained by ASM to generate different shape models. Then ASM was used to detect the face shape of the test sample, and compared the distance with each face shape model. Finally, nearest-neighbor algorithm was employed to accomplish classification. Experimental results show that the proposed method outperforms the methods based on curvature feature of face contour or feature of chin contour. The method can detect full face shape information, and improve the recognition rate and speed on huge face database.

Scrambling method based on itinerary of tent map

2009, 29(10):  2713-2715. 

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An audio and image scrambling method based on the itinerary of tent map was proposed. The codes generated by the itinerary of tent map could be applied in audio signal scrambling. In addition, digital image could also be scrambled as the map was extended to the 2-D case. The scrambling degree, period and robustness were discussed as well. Generally speaking, the proposed method owns larger period and better scrambling degree compared with the traditional scrambling by Arnold transformation.

Segmentation of scattered point data based on region growing method

2009, 29(10):  2716-2718. 

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To deal with scattered measured points effectively and exactly, an improved algorithm of region growing was presented． The method estimated the Gaussian and mean curvatures of scattered point cloud data. To improve the efficiency of coarse segmentation and provide an initial segmentation, the plane points were extracted, and then seven surface types were extracted from the signs of Gaussian and mean curvatures． Therefore, cloud data was refined by an iterative region growing method． For each seed region, the algorithm iterated between region growing and surface fitting to maximize the number of connected vertices approximated by a single underlying surface, and was terminated by outside noise. Experimental results show the algorithm is maneuverable and practicable.

Artificial intelligence

Dynamic differential evolution algorithm with random mutation

2009, 29(10):  2719-2722. 

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The dynamic Differential Evolution (DE) algorithm with random mutation was proposed. In this algorithm, the mutation strategies of DE/rand/1 and DE/best/1 were combined by linear decreased weight convex combination strategy to produce a new mutation strategy so as to dynamically use the advantages of DE/rand/1 and DE/best/1. In order to improve the global optimization ability of DE algorithm, exponent increased crossover probability operator, linear decreasing scaling factor and random mutation mechanism were introdunced. The test results on the four standard test functions show that the new algorithm has fast convergence, high accuracy and more robustness, more suitable to solve high-dimensional complex global optimization problems.

Application of improved PSO algorithm and wavelet analysis in foundation settlement prediction

2009, 29(10):  2723-2725. 

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The authors used the improved Particle Swarm Optimization (PSO) algorithm that has two subgroups and a mutation operator binding wavelet analysis to optimize neural network parameter to forecast the foundation settlement. Since the basic particle swarm optimization easily falls into the local minimal value, the authors divided the particle swarm into two subgroups. In one subgroup the inertia weight of the particle swarm optimization algorithm decreased when the iterations increased. And in the other subgroup the particle swarm optimization algorithm adopted big inertia weight to do the overall situation search. And the authors used this improved algorithm binding wavelet analysis to optimize the neural network parameter to forecast foundation settlement. The experimental result indicates that this method has strong global and local search ability, and has high forecast precision.

Improvement of PageRank algorithm by ant colony algorithm

2009, 29(10):  2726-2728. 

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This paper adopted the main idea of ant colony algorithm to improve the PageRank algorithm. Categorize the Web page according to the position of it in original sequence, compute the clicked number of the Web page acquired through the keyword search, and use the existing transfer function to operate the acquired result. The result was used as a factor to evaluate the degree of correlation between keywords and Web pages, so as to update the weight of the Web page, then obtain a new sort result. The simulation experiments show that this method is through peoples subjective choice, so closely associated with the returned results page, their weight has been added with various degrees of growth. Its ranking in the returned results would be enhanced and more easily retrieved and the precision ratio was improved.

Markov logic network and its application in text classification

2009, 29(10):  2729-2732. 

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This paper introduced the theory, learning methods and inference algorithms of Markov logic network that was also applied to the Chinese text classification. With reference to the discriminative learning algorithm for Markov logic network weights, MC-SAT, Gibbs sampling and simulated tempering algorithm in experiments, it proves that the method based on Markov logic network is better than conventional K Nearset Neighbor (KNN) method in text classification.

Collaborative filtering recommendation algorithm based on Bayesian theory

2009, 29(10):  2733-2735. 

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Considering that the effectiveness of the collection of neighbors is an important factor to influence the quality of the recommendation in collaborative filtering recommendation algorithm, a collaborative filtering recommendation method based on Bayesian theory was proposed in this paper. It got the value of the users preference for a certain characteristic by using Bayesian theory. In the calculation of the similarity degree, it considered users preferences. And then it calculated the collection of the neighbors. The result shows that it can provide better recommendation quality than traditional item-algorithm.

New reduction strategy of large-scale training sample set for SVM

2009, 29(10):  2736-2740. 

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It has become a bottleneck to use Support Vector Machine (SVM) due to such problems as slow learning speed, large buffer memory requirement, low generalization performance and so on, which are caused by large-scale training sample set and outlier data immixed in the other class. Concerning these problems, this paper proposed a new reduction strategy for large-scale training sample set according to the analysis on the structure of the training sample set based on the point set theory. This new strategy gets the potential support vectors and removes the non-boundary outlier data immixed in the other class by using fuzzy clustering. That can greatly reduce the scale of the training sample set and improve the generalization performance by effectively avoiding over-learning caused by outlier data, and finally speed up learning rate without reducing the classification accuracy.

Audio clustering algorithm based on Mean-Shift in broadcasting

2009, 29(10):  2741-2743. 

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Since most clustering algorithms depend on the number of the prior knowledge, a novel broadcasting audio clustering algorithm based on Mean-Shift was proposed. Firstly, a Principal Component Analysis (PCA) transformation was used to reduce redundant feature set information, which based on wavelet domain. Mean-Shift thought was applied to cluster the audio as the primary clustering. Then it used the fast nearest neighbor algorithm to revise the result of the first time, and merged the class that only contained single sample to the second correction. The experiment results show that clustering accuracy has been improved to a certain extent.

Ant colony algorithm for continuous space optimization

LIU Xi-en

2009, 29(10):  2744-2747. 

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A new ant colony optimization algorithm—Three Strategy of Intelligent Ants （TSIA）, based on the idea of classic ant colony algorithm and dynamic classification, was presented in this paper. The whole ant colony was divided into 3 sub-categories: random search category, local search category and targeted search category. And, using three-tier search strategy: the random search ants move in the random directions by random step lengths, the local search ants move by the way of pattern movement, the targeted search ants move in the direction of "best ants" by large steps. It makes the whole ant colony have a better balance in the "exploration" and "learning" to adjust the three sub-class sizes and the moving step lengths. It proves that the algorithm is simple and efficient with fast convergence and global optimization.

Prokaryotes gene identification based on nonlinear SVM

2009, 29(10):  2748-2750. 

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This paper presented a nonlinear least squares support vector machine method to identify the prokaryotes gene. This method generated training sample sets by searching sequence Open Reading Frames (ORF) and comparing ORF sets with reliable gene location document, extracted two sample features of GC content and Z curve, examined information content of these features by T-test, and designed nonlinear least squares support vector machine classifier to recognize gene. The results show that the recognition rates of nonlinear least squares support vector machine are 7.09%~29.97% and 10.97%~25.45% higher than Fisher and linear support vector machine respectively under different feature combinations, and the nonlinear support vector machine method performs better when the feature information content is less.

Prediction model of noniterative least squares SVM based on quadratic Renyi-entropy

2009, 29(10):  2751-2754. 

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A learning algorithm of noniterative Least Squares Support Vector Machine （LS-SVM） based on quadratic Renyi-entropy was proposed in the article by using quadratic Renyi-entropy in financial distress prediction. By comparing the model of LS-SVM based on quadratic Renyi-entropy with traditional LS-SVM, standard SVM, binomial Logistic regression model and Back Propagation Artificial Neural Network (BP-ANN), this paper concluded that either the number of training samples or the computing time, the model of noniterative LS-SVM based on quadratic Renyi-entropy is remarkably better than the others, as well as the stability. Indicated by demonstration analysis, the model of noniterative LS-SVM based on quadratic Renyi-entropy is successful in financial distress prediction. Meanwhile, although the number of input variable has been reduced by conspicuity test and gene analysis, the accuracy rate of the prognosis still reached 88%. In a word, the factor analysis method has been successfully proved in the article.

E-mail classification by SVM optimized with genetic algorithm

2009, 29(10):  2755-2757. 

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A method of classifying E-mail by Support Vector Machines (SVM) and Genetic Algorithm (GA) was proposed. In the first step, the mails were preprocessed, and then the combination of support vector machine parameters of C and kernel function parameters was optimized by genetic algorithm. Finally, the E-mail was classified by the optimized SVM . The experiments on a data set composed of 5800 mails show that the precision is 89.67%, which indicates that this method indeed improves the accuracy of filtering Chinese spam.

Emotional model based on ant colony algorithm

2009, 29(10):  2758-2761. 

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Emotion is a kind of important expression of human intelligence, and plays an important role in human decision-making process. In this paper, from the emotional characteristics, it extracted the carrier factors that influence emotions and introduced ant colony algorithm. Ants who carry the vector factor search the best emotional state to complete the task through the reaction intensity, in order to study the human emotional changes. Compared with the Hidden Markov Model (HMM), we can see that the emotional model of the ant colony algorithm is simple and reflects the changes in emotional states. The simulation results prove that this method is in line with actuality，and it is effective for the study of computational emotional expression.

Inventory optimization model with postponement strategy and its simulation

LIU Bingbing

2009, 29(10):  2762-2765. 

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In this paper, a sort of optimal inventory model with postponement strategy i.e. bilevel integer programming problem was researched. Bilevel integer programming problem was proved to be equivalent to constrained integer programming problem, and could be transformed to integer programming problem without constraint via penalty function. A genetic algorithm was proposed to solve this problem. The numerical simulation results show that the proposed model can improve the inventory benefits of overall supply chain，and reasonably adjust the optimal inventory of all branch points.

Data mining

Query schedule and load shedding model in data stream system

2009, 29(10):  2766-2771. 

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It is one of the major tasks to execute query timely with less performance and precise loss in a data stream system when the system resource is limited. This paper solved this problem from two aspects including optimizing operator schedule and performing load shedding. Taking different operators features into consideration, a scheduling strategy based on operator priority was presented, which comprehensively considered the factors related to the operators and the system running state. In order to dynamically modify the operator priority, the artificial neural network learning algorithm was also introduced, which can modify operator priority according to the system performance. Aiming to solve the potential overload problems caused by the uncertainty of the arrived data in a data stream management system, the load shedding issue of the data stream system was researched. Concerning the query of the two streams joint operators, a semantic-based load shedding technique was applied. A data stream load shedding model was designed and implemented, which solved four problems including load shedding and anti-shedding time, amount, location and predicate. The experiment result was analyzed, which showed that the load shedding model presented can effectively avoid the low processing efficiency when system is in the state of overload, and guarantee the coordination of arrived data and system processing capability.

Strategy of materializing views based on queries of time period

2009, 29(10):  2772-2773. 

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An effective method to reduce the response time to query is to materialize views in data warehouse. The current strategies mainly consider the methods of the primary selection of materialized views and the methods of dynamic updating. Concerning the situation that the updating of views based on queries of time period did not get enough attention, based on greedy algorithm and dynamic refreshment algorithm, the authors proposed a method of materializing views based on queries of time period. The method of materializing views based on queries of time period can meet the needs of clients, and enhance the efficiency of queries.

Research on mining typical anonymous users’ browsing paths based on Web logs

2009, 29(10):  2774-2777. 

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Through obtaining anonymous users’ browsing path set, on the basis of the new definition of path similarity, building the users’ browsing path similarity matrix, and based on this, designing anonymous users’ browsing path clustering algorithm to obtain the clustering result set and calculate various cluster centers, the typical anonymous users’ browsing path was got. Experimental results show that a typical anonymous users’ browsing path represents different types of users’ Web browsing path, which can be effective reference for Web site information recommendation.

Matching algorithm for twig patterns with parent-child edges based on ordered pair

2009, 29(10):  2778-2780. 

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With the development of Internet and the constantly increasing scale of XML data, how to query the XML data exactly and efficiently becomes a hot issue. At present, there are many algorithms for twig pattern matching, but they dont have good method to solve the twigs which have parent-child edges. The new algorithm called PCTwig was proposed for this problem, which was based on the ordered pair. The twigs were queried through setting the ordered pair of parent-child relationship on query tree and document tree. In query process, it can avoid useless intermediate result and merge operation. The experiment shows the effectiveness of the approach.

Feature selection based on linear discriminant analysis

2009, 29(10):  2781-2785. 

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The paper proposed a new approach of feature selection based on Constrained Linear Discriminant Analysis (CLDA), which modeled feature selection as a search problem in subspace and made optimal solution subject to some restrictions. Furthermore, CLDA optimization problem was transformed into a process of scoring and sorting features. Experiments on UCI machine learning repository and Reuters-21578 dataset show that the proposed approach can consistently obtain better results with fewer features than that with all features.

RFID data stream processing technology based on CEP

2009, 29(10):  2786-2790. 

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Radio Frequency Identification （RFID） data stream processing technology especially Complex Event Processing （CEP）-based approach is a hot spot in the RFID applications. This paper analyzed the characteristics of RFID data and the disadvantages of the previous CEP-based methods. Moreover a complex event processing method ERD was presented, which combined the detected event and intermediate result sharing mechanism organically and improved the detection efficiency of the overall system. Simulation results validate the effectiveness of the proposed method.

XML document information retrieval model based on four-layered Bayesian network

2009, 29(10):  2791-2795. 

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In this paper, a Bayesian model for XML document information retrieval was proposed, supporting content and structure queries. The topology and conditional probabilities of the Bayesian model were mined from the XML document collection by statistics of terms, elements and structural units contained in the collection. Combined with probability functions, the relevance of a document to a given structured query was obtained by an inference process through a complex dependences network of this model. Experimental results on the INEX corpus of XML documents show the validity and reliability.

Information security

Model for updating multi-topics on homepage based on Web data mining

2009, 29(10):  2796-2798. 

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To improve the reasonableness of updating multi-topics on homepage, this paper proposed a novel model based on Data Mining (DM). Firstly, after deep research of the present methods of updating topics, the irrationality of updating multi-topics on homepages, especially in college campus network, was pointed out. Then some valid data were extracted from Web log of Anhui University of Science and Technology (AUST) was used to analyze the continuously changing trend of click rate of every topic. Based on the obtained trend, a model for updating multi-topics on homepage was proposed. Experimental results show that the proposed model can reasonably update multi-topics，and enhance the popularity of homepages efficiently.

Design and implementation of identity authentication model based on keystroke rhythm

2009, 29(10):  2799-2801. 

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Keystroke rhythm is an identity authentication technique which takes persons behaviour characteristics as the basis. The PR-RP model were analyzed, in which four critical datasets were chosen, P-P and R-R relay dataset were rebuilt, and only the keystroke characteristics of password were processed. And then, a new characteristics template was built and real-time updated, which made the data in template always be the latest characteristics, so as to improve the recognition rate of authentication. Satisfied verification effects were achieved from the experimental data.

Study on temporal usage control model based on action logic

2009, 29(10):  2802-2805. 

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By using temporal modality logic in this paper, an action-based temporal usage control model was proposed with focus on atomic actions and temporal properties during a single usage process. The specification of the logic model consists of pre-defined authorization actions, a sequence of states expressed by attributes of subjects, objects, and the system, and state predicates. A policy language was introduced and its syntax and semantics were defined formally, and control policies were given according to action characteristics of core models of Usage Control (UCON). The logic model can not only depict the basic principles of UCON, but be helpful to precisely and automatically determine whether the policies could be satisfied, which shows good flexibility and expressive capability.

Risk assessment model for information system based on classification of risk events

2009, 29(10):  2806-2808. 

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A risk assessment model based on classification of risk events was proposed in this paper. In this model, each single risk event was classified into one of the bottom targets. Then the value of the bottom targets could be computed out. According to the target hierarchy, the risk value of an information system could thus be computed out. Finally, the fuzzy integrated assessment method was used in the proposed model to assess a system and get the risk value.

Fine-granularity discretionary access control based on user’s role

2009, 29(10):  2809-2811. 

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Fine-granularity discretionary access control based on Access Control List （ACL） may grant authority to one user or group, but it may grant unapt authority or remove authority not timely. Based on Role-Based Authorization (RBA) of trusted Kylin OS, introducing user’s role restriction in discretionary access control, a fine-granularity discretionary access control mechanism to user’s role was given. It can which may grant authority to the user with special role, and remove authority from the user without special role, therefore solves the problem of granting unapt authority.

Improvement of feature selection method in spam filtering

2009, 29(10):  2812-2815. 

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Spam filtering techniques based on content, especially feature selection algorithm was studied. Based on that, Mutual Information (MI) algorithm, combined with the feature of spam filtering, was analyzed and improved according to frequency, divergence, and concentration. Comparing with conventional mutual information algorithm, word frequency was introduced, and ratio of mutual information was used to evaluate the contribution to classifying provided by features. The improved formula and algorithm were given. At last, simulation test with real E-mail set, was conducted, which shows that the improved mutual information algorithm provides a better result for spam classification.

Study on buffer overflow attack description language of computer network counterwork

2009, 29(10):  2816-2819. 

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Under the background of computer network counterwork and taking buffer overflow as example, a buffer overflow attack description language was designed for it through analyzing embedded codes structure and features and abstracting the rule of buffer overflow attack. The actual verification shows that attack description language can correspondingly construct suitable embedded code and launch attack automatically.

Software process technology

Design and implementation of IAP techniques based on STM32F103VB

2009, 29(10):  2820-2822. 

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According to the requirements of firmware upgrade in embedded applications, the on-line software update solution based on the ARM Cortex-M3 32-bit RISC processor—STM32F103VB was given after introducing the feature of the In Application Programming （IAP） technique, and then the reliability of the solution was discussed. Finally, realization of on-line software update was given in detail. The solution realized on-line software upgrading based on STM32F103VB microprocessors in embedded applications, and shortened the development cycle and decreased the difficulty of maintenance for system software.

Design of E-mail client software based on embedded network terminal

2009, 29(10):  2823-2826. 

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Introducing the hardware systems and operating systems of embedded network terminal, a solution for E-mail client software based on embedded network terminal was proposed. And the design of E-mail client software was described in detail, after analyzing the E-mail system theory and related protocols. The E-mail client software was provided with greater flexibility and scalability. It not only can send and receive messages in both English and Chinese, but also possesses other functions, such as displaying the mail attachment content without downloading and so on.

Software testing method based on data processing model

2009, 29(10):  2827-2829. 

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Firstly, a software testing method based on data processing model was proposed to overcome those deficiencies of the traditional testing methods applied to data processing software. Secondly, the selection method of testing data based on the diagrams was put forward to avoid any blindness of testing data selection. Finally, using them in coordinate transformation software testing, the results show that the proposed method is feasible and efficient for software testing.

Research of multi-Agent data interaction model based on reflection

2009, 29(10):  2830-2832. 

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Based on the research of Agent theory, this paper pointed out that intelligent and flexible software could make its own adjustments based on the environment and requirement for business. This paper focused on combining reflection technology, through dynamic configuration as decision-making, and pointed out the model of multi-Agent data interaction based on reflection. The model could be used for the existing multi-Agent cooperation and coordination mechanism, and provided adaptive solution for data interaction in open, heterogeneous, dynamic environment. At last it was applied in the actual design of the system.

Modeling and verification of online judge system with B/S based on Petri nets

2009, 29(10):  2833-2837. 

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Online judge system is a representative system in dynamic transaction processing under network environment. The properties of static structure and dynamic behavior were not considered by the conventional design method of software. A hierarchical model of online judge with B/S was constructed by P/T nets. According to the function, some important qualities were presented to guarantee the correctness of system. The analysis and verification of the model are shown by S_invariants.

Design and implementation of embedded CORBA/e

2009, 29(10):  2838-2840. 

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Concerning the CORBA/e specifications of Object Management Group (OMG), a common implementation is to simplify the original CORBA interface. However for some specific embedded applications this leads to some problems like big size and non-optimized performance. This article analyzed the special requirements of CORBA/e and improved its current implementation. The obtained CORBA/e network middleware, has succeeded in embedded applications by integrating the design patterns and methods in relevant areas.

Model checking technology and tool development based on Groebner base

2009, 29(10):  2841-2843. 

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In this paper, a new model checking algorithm introduces the application of Groebner to reduce the polynomial formula in the property verification, and it can efficiently optimize the computing complexity problem. A new symbolic model checking tool was built based on this algorithm. And this tool is proved to be effective for different types of software and hardware system, and has high practice value.

Typical applications

Exploration of semantic Web service discovery based on QoS

ZOU Jin-an

2009, 29(10):  2844-2846. 

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Quality of Service (QoS) was introduced into semantic Web service in this paper. The authors analyzed the description of QoS ontology and the method of Web service discovery and the method of semantic Web service discovery, and established a general QoS model. Parameters of this model can measure almost all Web services. A semantic Web service discovery frame based on QoS was proposed. In the frame we firstly discover Web service by function, then evaluate the discovery Web service above based on QoS model, and lastly find out the best one. At the end of this paper, we established semantic ontology and QoS ontology with an instance.

Fake plate detection system based on grid monitoring

2009, 29(10):  2847-2848. 

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Concerning the wild increase of cars that use fake license plate, a fake plate detection system based on grid monitoring was presented. The system used license plate recognition technique to gather car information, such as license plate and the time it appeared. The system automatically detected fake plate with the rules that one car cant appear in two places at the same time. With a reliable license plate recognition technique, it can get a detection rate no less than 99%.

Load-balancing evaluation model based on pre-defined variability

2009, 29(10):  2849-2851. 

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An evaluation model of load-balancing was presented for finite difference parallel computing. Maximal Load Variability （MLV） was introduced as a key index for load-balancing, and the quantitative model was constructed with parallel efficiency as the object function, involving ratio of communication to computing, degree of parallel, problem size and complexity of local numerical schemes. Both the parameter MLV and the model were verified by analyzing the POP global ocean circulation model benchmark. The results show that the performance derived from the evaluation model is consistent with that of wall-time measurement on the whole. And the model given in this paper is also useful for those parallel applications with local schemes such as finite element and finite volume.

Design and implementation of augmented reality system based on hybrid tracking

2009, 29(10):  2852-2854. 

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To enhance the tracking capability of augmented reality system under varying conditions, an augmented reality system based on hybrid tracking was designed. It could dynamically acquire the dataflow from different sensors and schedule the corresponding tracking algorithm to integrate data and get the poison information finally. It manages all the hardware resource in augmented reality system and realizes the expansibility and portability. Finally, the application instance and analysis were given.

Modeling based on P-Agent for virtual maintenance prototype interaction

2009, 29(10):  2855-2858. 

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To improve the real-time and natural interactive mode in the virtual maintenance simulation, according to the virtual maintenance simulation requirement and interactive support, the P-Agent interaction modeling method was provided. Then the P-Agent and interaction modeling definition was given. Discussion was around the real-time and spontaneous interaction. The interactive mode was designed. Concerning that the communication primitive couldnt support the spontaneous interaction, it was extended to support more complex and more cooperative interaction. The application shows that the proposed modeling method has better interaction and real-time interaction, and is adaptable.

Detritus image segmentation using watershed transformation

2009, 29(10):  2859-2861. 

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Watershed is an image segmentation method based on region and mathematical morphology, and it is widely used in the segmentation of gray scale image. But the traditional watershed transformation has a serious problem of over segmentation, and noise of the image and fake textures may submerge the wanted edge information. Considering the characteristics of detritus image, this article proposed an improved segmentation method based on watershed transformation. During the pretreatment period, smooth the original image by applying morphological open and close reconstruction operation to reduce the side effects of noises, and relatively remain the edge of the image, then use nonlinear threshold transformation operation to part the background and the targets; after having extracted the targets, merge the small regions, and get the edge of the targets. Because the number of regions has greatly decreased as a result of the threshold transformation, computational complexity of the region merging was reduced. A new form of gradient was chosen to eliminate the drift of contours because of the morphology operation. Judging from the result of the experiment, this algorithm achieves pretty good segmentation outcome.

Study on optimization of logistics distribution route based on niche genetic algorithm

2009, 29(10):  2862-2864. 

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A mathematical model of logistics distribution route with time window was proposed according to the analysis of the logistics vehicle distribution process. The genetic algorithm had premature disadvantage, so the niche technology was introduced into the genetic algorithm and formatted the niche genetic algorithm. Finally, the niche genetic algorithm was used to solve the model, and the results showed that the niche genetic algorithm could avoid the premature phenomenon of the standard genetic algorithm in some degree and also could improve the efficiency of solving the logistic distribution route problem.

Design and implementation of SVG-based specific formula editing tool

2009, 29(10):  2865-2868. 

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The SVG-based formula editing tool used for specific domain solutions was proposed. With customized formula input rules, Java graphics programming and Batik software package, the editing tool was designed and implemented for evaluating performance of concurrent system described by Interactive Markov Chains （IMC）. The solution has a complete structure, easy to use GUI, convenient editing functions, etc. It displays formula perfectly and holds strong compatibility to be widely employed in various areas.

Design of embedded navigation digital map based on EVC

2009, 29(10):  2869-2870. 

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Considering the feature of the embedded system, an embedded digital map system based on Windows CE operating system was designed and developed. The resolution and conversion of the map data were realized using the Visual C++ 6.0; a map data structure for embedded devices was designed; the drawing of the digital map was realized through double buffering technique based on EVC 4.0. The experiments indicate the simple and feasible digital map system takes fewer resources and runs good, which can be used in mobile devices, navigation, etc., with good practical value.

Modeling and simulation optimization of purchasing process based on Petri net

2009, 29(10):  2871-2874. 

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Taking the purchasing process of a domestic large-scale manufacturing enterprise as research object, the models of purchasing process in the original environment and the optimized environment were built using the Petri net technology, and the performance under both conditions were quantitatively analyzed and then the strong and weak points in the original and the optimized processes were discovered by the simulation using the software ExSpect. The results show that the optimization of the original process by using the information technology and the reasonable supplier selection methods speed up the transferring and processing of the business information and shorten the purchasing period.

Research on building Chinese basic semantic lexicon

2009, 29(10):  2875-2877. 

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Judging the emotional tendencies of Chinese words is the basic work of the semantic emotional tendency study of text. Building a basic emotional lexicon with Chinese emotional words will provide a core subset for identifying emotional words in a special area. It is able to identify and enlarge emotional word set effectively in corpus and also improve the efficiency of classification. A method of calculating the emotional value of Chinese emotional words on the basis of the similarity of Chinese words was provided. And also a Chinese basic emotional lexicon dictionary was constructed based on the HOWNET emotional word set. The emotional tendencies of Chinese texts were judged through the dictionary together with TF-IDF. Experiments show that this method has achieved a satisfying result.

New model of unit construction general test-adapter for ATE

2009, 29(10):  2878-2880. 

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According to the actual electric matchings signal types and signal transfer directions in Automatic Test Equipment (ATE) test, a general test adapter model based on I2C-bus protocol was presented in this paper. This model included four parts, a signal-conditioning component, a channels-selecting component, an MCU for controlling test matching and a software management interface of the test adepter. In order to meet the demand of electric testing match, hardware components attached to I2C-bus can be chosen flexibly, that achieved the channels auto selection and signal conditioning. The model has high dynamic configuration ability and strong components reuse characteristics. It can meet the current demand of auto testing task.