Table of Content

01 August 2010, Volume 30 Issue 8

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Artificial intelligence

Logical AND operation model of variable precision lower approximation operator and grade upper approximation operator

2010, 30(8):  1991-1994. 

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Based on logical AND requirement of precision and grade, a logical AND operation model of variable precision lower approximation operator and grade upper approximation operator was proposed. In the new model, precise description and basic properties were obtained. Macroscopic algorithm and microscopic algorithm were proposed and analyzed, and a conclusion was made that microscopic algorithm had advantages in space complexity. Finally the new model and the algorithms were illustrated by a medical example. The new model has extended variable precision rough set model, graded rough set model and classical rough set model partially, and corresponding properties of approximation operators are obtained in these models.

Method for determining optimal number of clusters in K-means clustering algorithm

2010, 30(8):  1995-1998. 

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K-means clustering algorithm clusters datasets according to the certain clustering number k. However,k cannot be confirmed beforehand. A new clustering validity index was designed from the standpoint of sample geometry. Based on the index, a new method for determining the optimal clustering number in K-means clustering algorithm was proposed. Theoretical research and experimental results demonstrate the validity and good performance of the above-mentioned algorithm.

Heuristic algorithm of attribute reduction based on discernibility matrix

2010, 30(8):  1999-2002. 

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Comparing the records of one equivalence class with the records which belong to other equivalence classes will product lots of empty elementS and repeating elements, so that construction of the discernibility matrix will spend too much time and space. In this paper，firstly,the discernibility matrix was constructed by using information vector as a tool to deal with equivalence classes, thus the efficiency of space complexity and time complexity of constructing discernibility matrix was improved. Secondly, a heuristic algorithm of attribute reduction based on the discernibility matrix was presented by using attribute frequency as heuristic information. Finally, the experimented results validate the algorithm with celestial body spectra.

K-prototypes based clustering algorithm for data mixed with numeric and categorical values

2010, 30(8):  2003-2005. 

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Based on the K-prototypes, the clustering problem for data mixed with numeric and categorical values was researched in this paper. At first, an improved formula for computing the dissimilarity degree was proposed, compared with the formula in the K-prototypes algorithm. The modified formula can reflect the samples similarities and differences more precisely. Furthermore, a new clustering algorithm for data mixed with numeric and categorical values was presented on the basis of the improved formula for computing the dissimilarity degree, which was finally applied in the clustering analysis of English loanwords. The experimental results show that the new algorithm has better stability and higher precision than the traditional K-prototypes algorithm.

Double-stage spam filtering method based on rough set

2010, 30(8):  2006-2009. 

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How to combine the head information and body information of an Email for spam filtering has drawn many researchersattention. Owing to that the rough set is a useful tool to deal with uncertain information, a new doublestage spam filtering method was proposed. Firstly, the Emails were classified into nonspam set, spam set and doubt set according to the head information. Secondly, the doubt set was classified into nonspam set and spam set according to the body information. The simulation results on two Email data sets in English and Chinese respectively illustrate that not only the accuracy is improved but also the manslaughter rate of classifying nonspam emails into spam set is reduced significantly.

Rule learning algorithm based on structured attribute set

SHI BaiSheng

2010, 30(8):  2010-2012. 

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An algorithm with a filter function which exploring frequent concepts in a context was proposed with structured attributes in order to learn association rules. Simply changing the function, that algorithm could compute various kinds of conceptbased rules. The advantage of the presented method is to avoid the redundancy in the intent of the computed frequent concepts with the help of structured attributes. The resulted rules are, therefore, more concise and practical.

Multi-dimensional query optimization algorithm for bitmap index with binning

2010, 30(8):  2013-2016. 

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The storage requirements for simple bitmap index is unacceptable when cardinality （the number of distinct values）of the attribute is very high. A common approach to solve this problem is to build bitmap index with binning. This technique builds a bitmap for each bin in a certain attribute range rather than distinct values. But this approach cause the time waste during candidate check because candidate check usually dominates the most of query processing time. In order to improve query performance, a new sort method for attributes was propsed to reduce the number of candidate check. And then a dynamic prescan algorithm was proposed. The experimental results show that our approach has a significant improvement over traditional strategies.

Trajectory tracking of mobile robot using iterative learning control in polar coordinates

2010, 30(8):  2017-2020. 

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To improve the repetitive tracking performance of autonomous mobile robot for a class of special curves, the robots kinematics model was studied in polar coordinates; an openclosedloop Ptype iterative learning control (ILC) algorithm which is described in discretetime domain was applied, and the convergence proof of the ILC algorithm was presented under the given conditions. With the increasing iteration times, a better stabilization and convergence rate of the system can be achieved under dynamic uncertain environment. By taking the simulation control law as the initial control inputs on real robot platform firstly, the real control law can be obtained with less iterations under practical environment. The simulation results show good performance for tracking and the real experimental results verify the feasibility and efficiency on actual mobile robot platform.

Path planning of mobile robot based on improved artificial potential fieldField

2010, 30(8):  2021-2023. 

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This paper utilized an improved artificial potential field to solve the problem of Goals Nonreachable with Obstacle Nearby （GNON）. The improved artificial potential field adopted the improved potential function that ensured the goal is the global minimum so the robot can reach the goal freely. To address the local minimum problem in classical potential field method, a method composed of obstacles connection and discrete model of sensor of robot was proposed. The improved method was adaptable to path planning of robots in complex indoor environment. The effectiveness of the improved algorithm was verified by simulation.

Aging forecast model for application server based on rough wavelet network

2010, 30(8):  2024-2028. 

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Concerning the software aging in application sever, the systematic performance parameters were observed and the aging forecast model was set up based on Rough Wavelet Network (RWN).Then the dimensionality of input variables of RWN was reduced by information entropy reduction method, and the structure and parameters of RWN were optimized with adaptive genetic algorithm. Finally, the experiments were carried out to show that the aging forecast model based on RWN is superior to the wavelet network model and wavelet network model in convergence rate and forecasting precision.

Representation and application of interval-gap-based time ontology

2010, 30(8):  2029-2033. 

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Interval-gap-based theory was proposed to extend OWL-Time to represent the situation of a single event with gap-intervals and ontology. The concept and temporal relation in ontology were defoned based on interval-gap-based theory and the application of this representation in the domain was specified by the representation of transport event in logistics. The reasoner for the extension was built by defining the primitives, rules and extending the operation on inference model in Jena. The experiments on the reasoner not only verify the correctness of the reasoner, but also ensure the correctness of temporal knowledge represented in ontology and rules. With the method in this paper the problem of interval-gap-based temporal knowledge representation and reasoning is solved.

Method of Chinese word segmentation based on character-word classification

2010, 30(8):  2034-2037. 

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Chinese Word Segmentation （CWS） is the basic problem of natural language processing. A joint character-word classification model for Chinese Word Segmentation was presented, which mainly dealt with the problem of Conditional Random Field (CRF). On the one hand, the majority of errors in CRF caused by fine granularity were figured out in outside-layer of the model. On the other hand, excessive linked words caused by improper segmentations that were settled in core inside-layer. The experimental results show that the value of F is greatly improved and the good results of word segmentation are easily gained by choosing the hierarchical word segmentation model based on character word classification.

Mongolian part-of-speech tagging approach based on conditional random field

2010, 30(8):  2038-2041. 

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It is necessary to tag both stem and affix in the Mongolian part of speech tagging，in order to save lots of syntax and semantic information of affix and to reduce the size of Mongolian dictionary. This paper presented a new approach of Mongolian part of speech tagging based on CRF. To take advantage of the ability of using arbitrary features as input in CRF，the system exploited not only the contexts of words，but also new statistical features adopted for mutual influence between the morphemes. The system was tested in the 38000 part-of-speech dataset provided by Inner Mongolia University. The closed test results show that POS tagging accuracy of the testing set reaches 96.65%, outperforming the HMM-based model.

Approximation accuracies of a class of polynomial smoothing functions

2010, 30(8):  2041-2044. 

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In 2007, Xiong,et al.proposed a class of polynomial smoothing functions, whose approximation accuracy is a problem that has not been solved. This paper applied dichotomy algorithm to solve the problem. To overcome the shortcoming that the root might be missed by dichotomy algorithm, the problem of approximation accuracy for smoothing function was firstly expressed by the problem of solving the maximum value of approximation function, and the approximation function was divided into 4 segments and the maximum value of the each segment was sought respectively, then the maximum value of approximation function was obtained in the whole x-axis. Taking 1st-order and 2nd-order smooth polynomial functions as examples, whose approximation accuracies were solved by the dichotomy algorithm. The results show that the dichotomy algorithm is a effective way to solve the approximation accuracy for this class of smoothing functions of support vector machine.

Hyperchaos system with only one nonlinear term and comparative study of its chaotic control

2010, 30(8):  2045-2048. 

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In order to study the nature of chaos, a four-dimensional hyperchaos system with only one nonlinear term was constructed. In this paper the complex dynamics features including hyperchaos attractor, the Lyapunov exponent and the Poincare map were studied which proved the hyperchaos system's chaotic behavior. In order to better control this four-dimensional hyperchaotic system, the control simulation of the system was given respectively by the linear feedback control and adaptive control method which shows that linear feedback control method and the adaptive control method are effective and feasible to control the hyperchaos system with only one nonlinear term. At the same time, the advantages and disadvantages of the two kinds of control methods in controlling chaos system were compared.

Initial iterative learning control strategy based on CMAC neural networks

Xiao-yan DUAN

2010, 30(8):  2049-2051. 

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In order to avoid the problem of slow converging speed and long time expenditure when traditional iterative learning control system faced a new environment, an improved algorithm was proposed to obtain the initial value of the iterative learning control based on CMAC neural networks. Desired control input of iterative learning control, that was estimated by CMAC neural networks and feedback PID networks based on the historical control experience, worked as the initial control input of the iterative learning control.With the role of open-closed loop P-type iterative learning control algorithm, the actual output trajectory of the system could track desired trajectory in accurate requirements using less iteration. The simulation results of the robotic system show the algorithm is feasible and effective.

Advanced computing

Design and implementation of cost measurement for thread context switch

2010, 30(8):  2052-2055. 

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In a multi-chip multi-core computer system, the indirect cost of thread context switch is affected by the architecture, workload and scheduling strategy. In order to gain a more stable result, the measurement for thread context switch should take account of these factors. Based on the analysis of the Lmbenchs framework and working principle, a new program called LTC was designed and implemented. Considering the requirements of thread performance measurement, load models and scheduling policies were integrated into the LTC. The result shows that LTC is a good tool for analyzing the cost of thread context switch in a multicore system.

Parallel massive data oriented astronomical cross-match

2010, 30(8):  2056-2059. 

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Cross-match is the kernel technology to realize multi-band data aggregation. It must be resolved by computer technologies since the astronomical data sets are very large. This paper issues a parallel crossmatch function using PCAM parallel programming model. Because the performance bottle-neck of cross-match exists on data I/O accessing, this function balanced the amount of data reading and computation by tuning partition granularity, removing blank areas, improving data load and computation flow, and etc. Experiments prove that it can speed up large-scale crossmatch greatly. On the other hand, the support of both of the two most famous astronomical data index functions HTM and HEALPix were considered, and the performance comparison between them were analyzed through experiments. The high-efficiency cross-match function in this paper offers a technology conference for the projects such as national astronomical database and virtual observatory.

Dependable grid job scheduling mechanism

Yong-Cai Tao

2010, 30(8):  2066-2069. 

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With regard to the dynamic feature of grid, a Dependable Grid Job Scheduling (DGJS) mechanism was proposed in this paper. According to the deadline of job finish time, DGJS classified the submitted jobs into three levels with different priority: high QoS level, low QoS level and no QoS level. Based on the resource availability prediction, DGJS exploited reliability costbased job scheduling strategy, striving to schedule jobs to the resource nodes with high reliability. In addition, DGJS exploited different faulttolerant strategies for jobs with different QoS levels. The experimental results show that in the dynamic grid environments, DGJS increases the job success ratio and reduces the job finish time.

3D box-counting algorithm for calculating fractal dimension of cities

2010, 30(8):  2070-2072. 

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The traditional 2D box-counting fractal dimension algorithm has been extended to the 3D space, and a 3D-based box-counting fractal dimension algorithm was proposed. And, the 2D and 3D algorithm were used respectively to study the fractal characters of city. Through comparing the results, the fractal character of the spatial structure of cities along the third dimension was observed, proving that the traditional fractal cities study based on two dimensional fractal dimension algorithm, or simply adding "1" to the 2D fractal dimension to represent the 3D fractal dimension were not correct, furthermore, the correct method used in fractal city study was put forward.

Improved max-sum decentralized coordination algorithm

2010, 30(8):  2073-2076. 

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Coordination problems of large scale information system gradually become a hot spot, and the maxsum product algorithm shows a bright application future but with improvement of the convergence speed and the robustness. In this paper a decentralized message passing algorithm based on chaotic sequence was presented which can be used in cooperative systems and was operated in a canonical coordination problem (graph coloring ) performing decentralized coordination. The spacetime dynamic messages of factor node were generated using chaotic sequence and updated following optimized utilitymap and simple rules. Compared to maxsum product algorithm, the solution resolves computational bottleneck and shows a better performance in both convergence speed and robustness.

Graphics and image processing

New adaptive method for image denoising with keeping details efficiently

2010, 30(8):  2077-2079. 

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In order to keep more details while denoising, an efficient local adaptive image denoising algorithm based on the Double-density Dualtree Complex Wavelet Transform (DD DT CWT) was proposed. The principles and characteristics of the DD DT CWT were analyzed and a Bivariate Shrinkage Function (BSF) was derived. The noisy image was firstly decomposed by the DD DT CWT, then according to the statistical properties of wavelet coefficients and the dependency of inter-scale with intra-scale coefficients, the wavelet coefficients were shrunk by the BSF with local variance estimation, and finally the denoised image was reconstructed by the shrunk coefficients. The experimental results prove that the proposed algorithm is efficient in noise removal and details reservation, and can improve the visual quality of the denoised image.

Image denoising based on spatially adaptive Bayesian shrinkage in NSCT domain

2010, 30(8):  2080-2084. 

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A new image denoising method via spatially adaptive Bayesian shrinkage in the Nonsubsampled Contourlet Transform （NSCT） domain was propsed in this paper. the generalized Gaussian distribution was utilized to model the statistics of individual NSCT domain detail subbands. Anisotropic elliptic windows were then constructed and applied to the description of the local contextual characteristics of each coefficient located at a certain detail subband. As a result, an NSCT domain image denosing approach with spatially adaptive Bayesian shrinkage mechanism was established. The experimental results demonstrate the effectiveness of the proposed denoising method. Compared with four shiftinvariant contourletrelated denoising methods, the proposed method provides preferable denoised results.

Extended RGB color correction based on standard white board

2010, 30(8):  2085-2087. 

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A general technique problem in image processing is how to obtain the real chromatic rendition by color correction. In this paper, a color correction method based on standard white board was proposed. Firstly, the color space must be extended to certain accuracy so that a standard white board could be made. Then according to a such requirement, an appropriate corrector was chosen to calculate the value of RGB to correct the target image which was obtained under the same conditions with the corrector. Engineering and simulation analysis indicate that corrected image not only is consistent with the standard image in the visual, but also its numerical deviation is smaller than the result of traditional methods.

Image matching method based on perceptual organization of linear features in stereoscopic images

2010, 30(8):  2088-2090. 

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Compared with point features, high-level features, especially free-form linear features, contain abundant information, which are more beneficial to the consequent image interpretation and surface reconstruction, etc. But, the linear features that can be matched successfully with typical method are few. Concerning the weakness of typical matching methods, perceptual organization theory was introduced into the matching process, and an image matching method based on perceptual organization of linear features in stereoscopic images was proposed. According to the results of the experiment, this algorithm advances the success ratio of free-form linear features matching and increases the length of free-form linear features, which facilitates the subsequent manual objects extraction.

Improved multi-scale retinex image enhancement algorithm

2010, 30(8):  2091-2093. 

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For the existing problems of expensive calculation in the process of image enhancement with multi-scale Retinex, this paper presented an improved algorithm on the basis of fast two-dimensional convolution and multi-scale continuous estimation. Compared with the original algorithm, the new one was simpler for its superiority of making full use of the separability of the image Gaussian convolution and the feasibility of multi-scale continuous illumination estimation. Meanwhile, a histogram clipping method with removing extremum was proposed to deal with the color distortion of enhanced image, which could restore image color information and enhance image contrast. The experimental results demonstrate that the proposed method can efficiently increase the running speed while improving image quality.

Image thresholding method based on Fourier spectrum and moment-preserving principle

2010, 30(8):  2094-2097. 

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Aiming at the problems of the threshoding method based on the Moment-Preserving Principle (MPP), this paper presented an image thresholding method based on Fourier spectrum and MPP. Firstly the Cumulative Distribution Function Value (CDFV) was calculated according to the MPP to get the rough threshold value, then Discrete Fourier Transform (DFT) was carried out to the histogram of the image to be segmented and compute its Fourier Spectrum (FS), finally the CDFV and the FS were used to change the rough threshold value. Owing to good adaptation of FS,to the rough threshold, this adjustment could get an optimal threshold. Experimental results show that the proposed method can get better segmentation result and better generalization with high speed.

Wang Tile-based improved texture synthesis

2010, 30(8):  2098-2100. 

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Wang Tiles are constructed from four texture samples, and get ready for matching other Tiles. Because they are precomputed, Wang Tiles is a real-time way to generate textures. However, matching problems occur within Tiles and at the corners of adjacent Tiles. Therefore, a new technique of improving Wang Tile was proposed which generated Tile set and synthesized a large texture by replacing the center of edge-matching texture samples with a new sample, and using the Image Quilting pathfinding algorithm to find the instead path. The experimental results indicate that the rendered texture successfully overcomes these problems and enhances texture diversity to some extent.

New method of morphological color image processing

2010, 30(8):  2101-2104. 

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The definition of color morphological operators was proposed in this paper, which was based on the combination of weighted distance ordering of the reference color and improved lexicographical ordering. In the proposed approach which based on L*a*b* color model and its polar coordinates representation, vectors ordering which was mapped to scalar function with weighted impact factors were compared. A generalization of λ-modulus lexicographical ordering with the lexicographical ordering was proposed to solve the lack of equidistant, which could adjust arbitrarily quantitative function and reduce contributions of the preceding components in ordering. Compared with traditional distant and lexicographical ordering method in color image processing, favorable consistency in terms of human perception was obtained, better image color balance was maintained, and richer details of image edge and smoother processing performance were shown in the experiments results.

Fast feature-guided stippling method based on threshold matrix

Hui-Qin Wang

2010, 30(8):  2105-2107. 

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The traditional stippling methods have some deficiencies, for example, the distribution of stipples is not very reasonable, the features are not very clear and the iterations cost much time. In this paper, the fast feature-guided stippling method was proposed in accordance with the distribution and rendering of stipples. The distribution of stipples was generated by sampling on offset lines which were obtained by applying distance transformation to feature image. The rendering of stipples was the mapping procedure of threshold matrix generated previously to distributed stipples. The experimental results show that this method can help obtain good stippling style with reasonable stipples distribution. At the same time, the generating speed is increased greatly.

Color space conversion algorithm of generalized regression neural network based on digital proof

2010, 30(8):  2108-2110. 

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Color conversion algorithm of CMYK and CIE L*a*b* is the key technique in output device characterization and color management module. In this paper the forward and reverse color space conversion models between CMYK and CIE L*a*b* based on Generalized Regression Neural Network (GRNN) were built using the color data of the digital proof. Then the accuracy of the models were tested. Finally, The result shows that it is an efficient method to build the color space conversion between CIE L*a*b* and CMYK using GRNN, which gains an advantage over BP network not only in training convenience, speed but also precision. network not only in training convenience, speed but also precision.

information security

Dynamic trust model based on fuzzy set in heterogeneous wireless network

2010, 30(8):  2111-2113. 

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A dynamic trust model based on fuzzy set (DTMBF) was proposed to solve the new security challenges in heterogeneous wireless networks (HWNs). In the model, the fuzzy membership degree was used to show the subjectivity and indeterminacy of the trust. The trustworthiness evaluation incorporated direct trust, recommendation trust, reputation of recommenders and time stamp. These parameters were adjusted in time using trust feedback control mechanism. Direct and recommendation trust reflected how well the candidate network has fulfilled the service agreements in the past. Reputation of recommenders and time stamp were introduced to show the creditability and time efficiency of the trust feedback. The simulation results show the DTMBF model can accurately evaluate the trustworthiness of the network and effectively restrain the acts of slander and co-fraud.

Implementation of layered model based on evolutionary theory

2010, 30(8):  2114-2119. 

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After deep analysis and rigorous logic reasoning of the trusted computing, the trust model based on evolutionary theory in the trusted computing environment was established. Through the definition on trusted chain and trusted layer as well as description of credibility in three main attributes, the logical structure was realized. Through trusted root broadcasting based on legal rights and obligations in broadcast networks, and establishing trusted root based on trusted storage in trusted terminal, physical structure in trusted computing environment was achieved. The implementations made the common computing platform suitable for trusted computing environment, solved the external and fair issues in trusted computing environment, and reduced validation overhead brought from proactive of trusted terminal. The convergence of credibility was realized in the trusted computing environment at the smallest costs.

Cross-domain mechanism of anonymous attestation for distributed network

ZHOU YanWei 周彦伟

2010, 30(8):  2120-2124. 

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The restriction of computing and storage of Trusted Platform Module （TPM） and authentication complexity of Direct Anonymous Attestation （DAA） results in that DAA mechanism is for single-domain. In order to overcome this limitation, a DAA for cross-domain was proposed in this paper, considering paralleling, high-performance and co-processing in distributed network. The mechanism introduced a trusted third party-Certificate Arbitration Center(CAC) to verify the reality of requester's platform certificate, which issues the cross-domain certificate to the requester with real TPM. The certificate is issued once for repeated usage, which prevents CAC becoming system bottleneck. The mechanism reaches the controllable anonymity, and the analysis with universally composable security shows that the mechanism realizes the cross-domain anonymous attestation securely.

Novel masquerader detection scheme in sensor networks

2010, 30(8):  2125-2129. 

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Concerning the masquerader attacks in the sensor network, a new masquerader detection scheme was proposed. By means of the identity-based signature technique and node alarming rules, a single masquerader detection algorithm was constructed, which was based on the neighbor mutual authentication. Moreover, an algorithm to detect multiple masqueraders was acquired from this. In addition, the succeeded masquerader detection algorithm was proposed in this scheme in which the sink nodes monitor and examine the malicious region, and the normal nodes identify and transmit the alert messages. The proposal scheme is applicable to complicated masquerade attack and high network security demanding environment. The simulation experiments show the effectiveness in detection of the proposed scheme.

Escape technique of AVM2 virtual machine based on verification deception

2010, 30(8):  2130-2133. 

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The usage, value of security study, and present situation of escape techniques of AVM2 (ActionScript Virtual Machine 2) were introduced. Starting from the flaws of ABC verification in AVM2 security model, with host environment vulnerabilities and byte code simulation engine vulnerabilities, the technique details of the escape based on verification deception were then analyzed. Finally, according to the current research, proper strategies of defense and the target to improve in the next phase were given.

Detection of malicious content attacks on Web services

2010, 30(8):  2134-2138. 

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Malicious content attacks based on SOAP messages have great impact on application and popularization of Web services. In order to detect the malicious content in SOAP message, this paper proposed a new method of SOAP message signature detection. This method defined the SOAP Item and SOAP Rule to describe the feature of malicious content, and introduced the SOAP message parsing algorithm and SOAP rule matching algorithm to detect the malicious content attacks detection. According to this proposed method, a prototype system of Web services attack detection was designed and implemented. The experimental results of attack detection and performance analysis show that this system has good detection effect and performance.

Evaluation of vulnerability static severity based on attribute synthetic assessment system

2010, 30(8):  2139-2142. 

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To solve the problem of evaluating static severity of computer security vulnerability, a method of evaluating vulnerability static severity based on the attribute synthetic assessment system was proposed. Four factors: threat, epidemic, incidence and easy or hard repair were advanced from the basic attributes of vulnerability, and the proposed method used the attribute synthetic assessment system to get a binary tuple denotation of vulnerability static severity of which qualitative denotation shows static severity rank and quantitative denotation shows static severity metirc. Application cases show that the proposed method is exact and effective. Compared with other existing methods, the proposed method has merits of quantitative and qualitative denotation, and embodies nuance of different vulnerabilities which are in the same quantitative static severity level.

Quantum evolutionary algorithm for optimizing network intrusion signature database

ZHANG ZongFei

2010, 30(8):  2142-2145. 

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Concerning the poor performance of the intrusion signature database in network intrusion detection system, the Improved Quantum Evolutionary Algorithm (IQEA) of optimizing network intrusion signature database was proposed in this paper. The IQEA adopted eigenvector to express chromosome structure, initialized population based on the idea of niche cooperative evolutionary, designed the fitness function based on the matching degree of individual, and used the strategy about the dynamic update of quantum rotation corner and the cross of excellent individuals to evolve population. The simulation results show that the IQEA is superior to QEA and EA in search ability and convergence rate, and the intrusion signature database optimized by IQEA has better detection ability and self adaptabili

Automatic generation method for penetration test programs based on attack graph

2010, 30(8):  2146-2150. 

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In order to fulfil the need for network security management, a new automatic generation method of penetration test programs was proposed in this paper. The penetration attack graph was set up with the inference relation of the vulnerabilities in the target network through the forward breadth-first search strategy which combined knowledge of atomic attack. The system produced penetration test programs through reverse depth-first traversal attack graph. A prototype of penetration test programs automatic generating system was designed and implemented on the basis of this method. The illustration indicates that this method can effectively set up the penetration test programs which provide a useful reference for network security analysis.

Certificateless signcryption scheme in standard model

2010, 30(8):  2151-2153. 

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Most of the current identity-based signature schemes are secure in the random oracle model, but many of them have security problem. In this paper, an efficient and provably secure identity-based certificateless signcryption scheme was proposed. The scheme was proved secue in the standard model and reduced the q-Augmented Bilinear Diffie-Hellman Exponent (q-ABDHE) problem. Compared with the known identity-based scheme in the standard model, the proposed scheme has shorter signature length and less operation.

Free-starting preimage attacks on BLAKE-32

2010, 30(8):  2154-2156. 

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As one of SHA-3 candidate algorithms for the second round competition, BLAKE adopts local wide-pipe technology and improved MD iteration structure. Its core is the core of Chacha cipher algorithm and its security has not been proved. By analyzing the structure and the characteristics of message permutation, three rounds free-starting preimage attack could be applied to BLAKE by using splice-and-subsection technology. The result shows that the designing deficiency of message permutation affects the security of BLAKE algorithm.

Compression algorithm of state transition table based on sparse matrix

2010, 30(8):  2157-2160. 

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Regular expression matching is essential for network security applications. In this paper, a smi-SCT (State transition Compressed Table of sparse matrix index) algorithm was proposed.Firstly a sparse matrix and index table were introduced into Deterministic Finite Automaton (DFA) with a general create method of them. Then combined with the smi-SCT with alphabet compression table algorithm, an optimization strategy of the algorithm was given. At last proved the compression effect of smi-SCT and gave the applicable scope of smi-SCT according to the experimental results on compression effects.

Watermarking algorithm for resisting local nonlinear geometric attacks based on normed centre of gravity

2010, 30(8):  2161-2163. 

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An image watermarking scheme based on Normed Centre of Gravity (NCG) and lifting-based wavelet resisting nonlinear geometrical attacks was proposed to achieve the copyright protection of digital image in this paper. Firstly, the watermark image was preprocessed by employing scrambled. Secondly, wavelet transformation based three-level lifting for the original image was conducted, and then NCGs were detected from the low frequency and high frequency components, then the feature vector was generated by taking distances between NCGs. Finally, the copyright information was obtained by calculating the watermark and feature vector. The experimental results show that the scheme can well withstand local nonlinear geometric attacks, meanwhile security of the algorithm is guaranteed by using secret keys.

Semi-blind watermarking algorithm based on SVD-Winograd fast transform

2010, 30(8):  2164-2166. 

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At present most of the methods based on Fourier transform domain have very good performance against geometric attacks and with a great amount of information embedded, but they have poor resistance to shear attack. Therefore, a semi-blind watermarking algorithm based on Singular Value Decomposition (SVD) and Winograd fast Fourier transform combination was proposed. In the SVD process, the first singular value decomposition of the diagonal matrix with the Winograd fast Fourier transform decomposition of the diagonal matrix to matrix multiplication, resulting in a new diagonal matrix. Then digital watermark was embedded into the new diagonal matrix. Finally the watermark was extracted through the relevant operations. The experimental results show that the method can obtain better image visual effects, and is of good robustness against shear, noise, rotation and other attacks.

Proxy blind signature scheme based on DLP

2010, 30(8):  2167-2169. 

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The proxy blind signature scheme based on DLP proposed by Tan et al. was analyzed, and it was found that this scheme does not possess the unforgeability. The original signer and the receiver could both forge a valid proxy blind signature for any message. At the same time, the proxy signer could make a linkage between a message signature and the corresponding blind message signature, which was called linkability. So an improved proxy blind signature scheme was proposed in this paper, which can not only resolved the security problems existing in the original scheme, but also has high efficiency.

Software process technology

Ontology-based service network platform and its construction method

2010, 30(8):  2170-2172. 

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As SOA being widely used, it is more and more important to meet the growing needs of large-scale Web services management and automatic Web service process. Based on Service Network (SN) model, which is a semantic relations-based Web service infrastructure, a Service Network Platform (SNP) and an approach of evolving SN was proposed in this paper. The definitions of Web service and service relations were provided, which make it possible for automatic processing Web service. The dynamically optimized service network system core was designed which implements the data storage, SN optimization and relation mining. A suit of SN core tools were designed and implemented which contains SN creator, service increasing module, SN viewer, and so on. The relations' construction approach based on service classification and service annotation was provided, which evolves the SN system. Finally, some applications based on SN prove the effectiveness and the applicability of this platform.

Semantical analysis and modeling for OWL-S based on CSP

2010, 30(8):  2173-2176. 

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In order to implement automatic verification of OWL-S process model, this paper present a semantical model for OWL-S process model based on Communicating Sequential Process （CSP）. The formal semantical model of CSP was established and could be used to define the formal semantics of OWL-S processes. Finally, to show a complete process of how to define the formal semantics of OWL-S using CSP model, a flight-booking example was given. Due to the well defined mathmatical foundation, it is easy to develop a kind of tool verifying OWL-S processes automatically which increases the safety of the systems.

Gap analysis method for domain requirement and its application

2010, 30(8):  2177-2180. 

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The development of the domain information source facilitates the domain requirement. Few of the existing domain analysis methods nowadays can clarify the evolution process of domain requirements. Therefore, the method of gap analysis for domain requirement was presented in this paper, which was used to analyze the evolving process in a specific domain. This method analyzed the differences between the as-is requirements and the to-be requirements on the basis of the domain prototype system. Then, the problem-domains that need to be focused on in the evolution process of domain requirements were got, and the evolution model of the domain requirements can be built accordingly. This method is applied in the requirement analysis of banking system, and the effectiveness of the method has been well verified.

Safety test environment for safety assessment oriented CTCS-2 train control system

2010, 30(8):  2181-2184. 

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The CTCS-2 train control system of high speed railway is a typical safety-critical system. In term of the characteristic of safety-critical system and with analyzing the requirements of safety test and evaluation of the CTCS-2 train control system of high speed railway, the test script language-SED_TSL was designed which driven by scenarios and events. Then the functions, system architecture and test strategy of the test environment for the CTCS-2 train control system of high speed railway were proposed, the automatic test environment of CTCS-2 train control system based on the SED_TSL was implemented. The automatic test environment was used for standard testing of the product in the train control system, and implementing effectively the functional and safety test of the product of train control system.

Functional testing method for Web applications based on TTCN-3

2010, 30(8):  2185-2188. 

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For the growing demands of Web application functional testing and test reuse, a TTCN-3 based Web application functional testing method was proposed. The method combined hierarchical thinking with TTCN-3 features, and divided Web application functional testing into three levels: page testing, and session testing, scenario testing. The TTCN-3 test processes were given respectively from three levels of Web application. This method used parametric designing idea of TTCN-3 test cases, effectively separated test design and test implementation, so that test cases would be highly reusable. Examples illustrate that the method is effective.

Research and implementation of unit testing framework based on three-layer architecture

2010, 30(8):  2189-2192. 

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The unit testing is fundamental and also the most important step in the whole testing system. Through the deep research of the characteristics of the three-layer architecture，In this paper a unit testing framework based on the three-layer architecture was proposed,In this architecture,a popular interface-oriented programming was adopted, meanwhile, the flexible designing patterns were used to effectively guide the whole testing process. Currently, the whole framework has been put into practice and also has been proved feasible by practice. It can discover the hidden problems in the process of the software development, more effectively ensure the quality of the Web application procedure and cut down the expense on the latter maintenance.

Hash table based on Trie-tree

2010, 30(8):  2193-2196. 

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A Hash table based on Trie-tree was proposed, based on idea the Aho-Corasick (AC) algorithm and the chain-hash. This algorithm, by adding a counter of the subsequent state, could supply simpler and faster information for the follow-up search operations and so on. The analysis and the experiment indicate that this algorithm is of higher efficiency,stronger stability and less energy consumption.

Network and communications

New grid resource management framework for mixed types of workloads

2010, 30(8):  2197-2201. 

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In the past years, most existing grid resource management techniques focus on performance improvement for one kind of workload, while ignoring the scalability of resource provision for multiple types of workload, which restricts the grid system application to more fields besides e-science. This paper proposed a new resource management model and its implementation framework for mixed types of workload that can support diverse workload simultaneously, such as batch workload, service workload etc. The proposed policy that constrained resource allocation method can make the resource achievement satisfy the performance specification of each workload by abstracting "workloads-resources" sharing relationship into consumer sharing policy tree, so that the user utility of whole system is greatly improved.

TA-ONS — New enquiry system of Internet of Things

2010, 30(8):  2202-2206. 

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According to the insufficiency of the traditional Internet Of Things (IOT) on privacy protection, an improved enquiry system of IOT-Trusted Anonymous Object Naming Service (TA-ONS) was proposed with trusted computing technology, adding anonymous certification to the traditional ONS enquiry system of IOT, authenticating the identities and platform creditability of local ONS servers (L-ONS), and giving temporary certificates to validated L-ONS. Within the authentication period, L-ONS could apply for more than once enquiry services from TA-ONS with the certificate. TA-ONS only provided enquiry services to those authorized and trusted L-ONS, prevented the illegal L-ONS to enquire information of things. The universally composable security model was used as safety check. The analysis shows that the new enquiry system model of IOT is safe, anonymous, trusted and efficient.

Dynamic queue assignment algorithm under IEEE 802.11e

Zheng WAN

2010, 30(8):  2207-2209. 

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In this paper an improved dynamic queue assignment algorithm based on the ideas of cross-layer optimization and unequal protection under IEEE 802.11e was proposed. In this algorithm, queue AC[1] and AC[0] were utilized to transmit video frame. Queue priorities, which were utilized to map with video frame priorities, were calculated according to queue status. The proposed algorithm assigned a queue for a video frame according to the priority of the frame and the congestion conditions of different queues. The simulation results show that video distortion can be greatly decreased by using the proposed algorithm.

Study of routing strategy on complex networks

2010, 30(8):  2210-2213. 

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Compared with regular networks and random networks, complex networks can describe the characteristics of networks better. Routing strategy is important to the information dissemination and exchanging in networks. In recent years, the routing in complex networks has become a research focus. In this paper, the existing routing strategies which including the traditional routing method, the biological behavior based routing strategy and the sociological behavior based routing strategy were discussed, then the direction of further research was pointed out .

Capture of long-period PN code using spectrum correction in high dynamic doppler shift situation

2010, 30(8):  2214-2217. 

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For the problem of power leakage and scallop loss in PN code capture that bases on Fast Fourier Transform （FFT）, spectrum correction was used according to the analysis of method based on the PMF-FFT. While spectrum correction of the maximum power spectrum after FFT, the maximum amplitude was increased, the sidelobe interference was restrained, and a more accurate Doppler shift was obtained, so that a higher detection probability was got. At the same time, signal model and theoretical analysis expression based on this algorithm were shown. On the basis of the theoretical analysis, the computer simulation results show that the method has good capture results.

New method to suppress cross-terms of Wigner-Ville distribution

2010, 30(8):  2218-2220. 

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A new method was proposed to suppress the cross-terms of Wigner-Ville distribution. First，the cross-terms were detected between the Wigner-Ville and the Margenau-Hill distributions based on the geometry difference of cross-terms representation，then a mask filter was designed to eliminate them. Finally，the results of simulation indicate that this technique is feasible.

Adaptive blind presence detection algorithm for burst signals

2010, 30(8):  2221-2223. 

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An adaptive blind presence detection algorithm for burst signals was proposed in this paper. A spectral variance function was chosen as the detection function, the change of background noise was tracked by establishing a noise function set with the threshold adjusted adaptively in real time. Then, the length of control and a stat-transition mechanism were used to mitigate the effect of dithering of detection function on the decision results. The simulation results show that the proposed method has a better robustness and a higher detection probability for burst signals compared with short-time energy method and spectral entropy method.

Network utility maximization of coded packet network under delivery contracts constraint

2010, 30(8):  2224-2227. 

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The paper studied the problem of network utility maximization of coded packet network under delivery contracts constraint when coding subgraph was given. Based on the network utility maximization model proposed, a distributed projection subgradient algorithm for this problem based on dual decomposition theory was developed, and the sufficient condition that can make the algorithm converge to the globally optimal solutions was proved. In the end, numerical example verifier the correctness of the algorithm.

Typical applications

New update method with high-reliability for embedded system software

2010, 30(8):  2228-2231. 

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Concerning the shortages of traditional embedded software updates, a new on-site update method with high-reliability was proposed, which achieved embedded system software updating by copying update files from a SD card to the flash partitions of the embedded device. On condition of fast update, the compatibility detection of update files for fault-avoidance, the double-Bootloader design, the test and verification of the update files, and the exception handling mechanism were adopted to effectively improve fault-avoidance and fault-tolerance properties of the software. The high reliability of this method is proved through the reliability assessment based on the Nelson model and the application in the product.

Network propaganda machine model based on search engine optimization

2010, 30(8):  2232-2234. 

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Due to low productivity and low efficiency, artificial processing holds back Search Engine Optimization (SEO). In order to deal with it, a network propaganda machine model based on SEO analysis was proposed, and its main idea, key algorithms and working flows were described in this paper. Further, backward spider technology was utilized to collect sorted information and to search optimized key words by matching operations worked in an overlay space. Then, Monte Carlo algorithm was atopted to estimate all characters and to prove the accuracy and efficiency. The simulation comparisons show that the proposed model has better sort performance and clients satisfaction than the traditional one.

Grading model of seed cotton based on image features

2010, 30(8):  2235-2238. 

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In order to improve the accuracy and objectivity of classification of seed cotton, the paper presented a grading model. The model was based on image features and used BP neural networks as the classification algorithm. According to GB1103-2007 national standards of seed cotton, white degree, yellow degree and impurity degree were extracted as characteristic parameters. The BP neural networks were trained with part of the samples. After completion of the training, the left samples were substituted into the trained networks, and the result showed that classification precision of the model was 81%. The experimental results show that this model can promote grading accuracy and objectivity.

Human abnormal behavior identification algorithm based on time-spatial Markov random field

2010, 30(8):  2238-2240. 

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Concerning the sudden-violence abnormal behavior between people, an algorithm which could identify abnormal behavior and other normal behaviors more accurately from images was proposed. This algorithm was based on traditional image segmentation technique, adopted the feature of neighborhood-related-only and the motion feature of adjacent frame in Markov Random Field (MRF), reconstructed the Gibbs energy function. This algorithm considered not only the spatial-information between every pixel and its neighborhood, but also the time-information between successive frames was added in to calculate the whole energy value in the acquired images, which those energy data could be analyzed by using the energy curve. Finally the effectiveness of this approach has been proved by comparing with the traditional optical flow method.

Bullet holes recognization based on color similarity measurement

2010, 30(8):  2241-2243. 

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In view of the shortage existing in the method for small bullet holes recognization,a new method which used color image as the data source was introduced in this paper.With analysis of image characteristics of bullet holes which were describled by color similarity, the template of 3×3 square area was bulit as the basic comparison unit to get the differences between the preshot image and the after-shot image, and then the areas where the threshold was satisfied the human eye recognition were extracted from which the bullet hole features were recognized by analyzing the image. Compared with the existing methods, the experimental esults show that the approach could utilize the information consisted in color image fully which not only can recognize the bullet holes which has 2% difference between background, but also meet the color visual characteristics.

Vehicle-logo recognition method based on image quality and PCA subspace

2010, 30(8):  2244-2246. 

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Concerning the low recognition rate of vehicle-logo images which were shot outdoor under moving conditions and with a variety of qualities, a new recognition method was proposed based on image quality and Principal Component Analysis (PCA) subspace. Firstly, the image fuzzy degree was computed according to fuzzy theory. Then the training samples were divided into different subsets in terms of fuzzy degree and their corresponding PCA subspaces were constructed. At last, the vehicle-logo was recognized in the specific subspaces which were chosen by the vehicle-logos fuzzy degree. The experimental data show that the reconstruction errors based on this method are less than those of traditional PCA subspace, thus the proposed method has more powerful capability in pattern depiction and can obtain higher recognition rate. The comparative test results further indicate the validity of this method.

Surface defects detection technique for steel strips based on artificial immune system

2010, 30(8):  2247-2249. 

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The traditional algorithms of surface defects detection for steel strips cannot achieve expected results because of the image noises, and inadequate or uneven illumination. To address this issue, a new method based on artificial immune system was proposed. According to the spatial inclusion relationship between detector and antigen, as well as self location information in domain, block-based detector generating algorithm was introduced to obtain the height information of surface defects for steel strips through three-dimensional recovery of their gray-level images, thus the three-dimensional quality of surface defects detection for steel strips was achieved. The experimental results show that the proposed method has an excellent effect compared with the traditional image detection algorithm in the condition of low contrast ratio uneven illumination or noise interference.

Adaptive defect detection of composite plate based on grey system theory

2010, 30(8):  2250-2253. 

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Target detection is a key step in image processing. In this paper, the adaptive defect detection of composite plate was realized. Firstly, The composite plate image was processed by oriented light compensation, then a new all-zero grey correlation model based on grey system theory was constructed. And then a finite difference adaptive method using gray histogram was adopted to realize the dynamic threshold segmentation. The theory analysis and real application of this method indicate that it has advantages of low false detection rate, high stability, strong adaptive ability, simple algorithm and so on.

Design and realization of specialized wire-grinding machine system based on ARM7 and CPLD

2010, 30(8):  2254-2256. 

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In order to meet the special requirements for the thrum of wire core in the aerospace field, a specialized wire-grinding machine was developed. This equipment used the ARM7 microprocessor LPC2214 as core controller and CPLD single-chip EMP570 as feedback circuit, to control the servomotors with high precision. In order to get a smooth and flat section, the wire core was rubbed out with precise length by the reciprocating moving sandpaper which was driven by the motors. This machine has already been utilized in real production, and proved to be quite effective.

Middleware of wireless embedded medical devices interacting with database

2010, 30(8):  2257-2260. 

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Considering the higher system requirements and the problem of slower access speed when the wireless embedded medical devices interact with database, this paper put forward a middleware that made wireless embedded devices interact with hospital database based on Socket and XML. This middleware established the communication link with embedded device by Wi-Fi, worked by receiving the request from wireless embedded devices to access the database, and converted the result set to XML document then returned back to the wireless embedded device. The experimental results show that this middleware can solve the interaction problem of wireless embedded devices and database in various operating systems and achieve higher efficiency.

Advanced computing

Improving downloading performance in hadoop distributed file system

2010, 30(8):  2260-2065. 

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Concerning the problems such as low downloading efficiency and imbalanced load of DataNode in Hadoop Distributed File System（HDFS）. Inthis paper two methods to optimize were proposed, one was to improve the whole process of downloading a file, the other was to optimize the downloading a block by a parallel download algorithm for dynamically allocating load by speed. Mathematical analysis and experiments prove that two methods can enhance the efficiency. Meanwhile, by combining the two methods, downloading is more efficient, and more stable when the load of DataNode can be balanced to some extent.

Typical applications

Application of neuro-fuzzy control to marine autopilot

2010, 30(8):  2260-2264. 

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Neuro-fuzzy control technology was applied to marine autopilot. The nero-fuzzy controller for autopilot was designed in this paper. Learning ability of neural network was utilized to optimize the fuzzy controller. Hybrid learning rule, a combination of Back Propagation algorithm (BP) and Least Square Estimator (LSE), was utilized to realize parameter adjustment of fuzzy control rule and membership function in order to improve the adaptive capacity of the controller. The simulation result shows that the controller designed is effective and feasible to satisfy the control performance requirements when marine is under wave interference.

Efficiency evaluation model of joint air defense operation based on advanced evidence reasoning

2010, 30(8):  2265-2268. 

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According to the advantage in dealing with uncertainty reasoning problems, the evidence theory was introduced to evaluate the efficiency of joint air defense operation. Firstly an ordinary model based on evidential reasoning was proposed, then fuzzy theory was applied to solve the problems with fuzzy concept or relations.The advanced evidence model was introduced to evaluate the efficiency of joint air defense operation aiming at the weighted or correlative evidence combination problems occured in actual condition. An example has been given to show the correctness of this new method and show the practicability and effectiveness in efficiency evaluation of joint air defense operation.

Audio watermarking for copyright verification and content authentication

2010, 30(8):  2269-2271. 

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A multipurpose watermarking scheme was proposed to provide a solution for some applications that require both copyright protection and content authentication. A robust watermark, in the form of a binary image, was first embedded in Mel-Frequency Cepstral Coefficient (MFCC). Then, the watermarked MFCC was coded to be binary string as a fragile watermark to be embedded in the DiscreteCosineTransform （DCT） domain. Blind detection was achieved for both robust and semi-fragile watermarks. The experimental results show that the proposed method is sensitive enough to detect malicious modifications and is capable of locating the regions that have undergone malicious manipulations. Besides, it is also effective to detection reliability, embedding capacity and robustness against common signal processing operations.

Performance analysis for audio information hiding algorithm based on spread spectrum

2010, 30(8):  2272-2274. 

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Audio information hiding algorithm based on spread spectrum is generally detected by correlation threshold, but the orthogonal of pseudorandom sequence is always destroyed by perception reshaping. In order to reduce the correlation noise induced by original signal, this paper analyzed the statistical characteristics of audio signal, pseudorandom sequence and channel, and derived the mathematical expectation and variance, and gave out the connection of these parameters. Finally, the results from the simulation and experiment prove that these expressions are correct.