Journal of Computer Applications

Yi-Yu YU

2008, 28(10): 2455-2458.

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A trust model was proposed for the open grid market. Our trust model emphasizes the importance of both direct trust and indirect trust/reputation when evaluating the trustworthiness of a grid service provider. Since many factors contribute to the direct and indirect trusts, a new method based on Multiple Attribute Decision Making (MADM) theory was proposed to determine the objective weights of both direct and indirect trusts. The simulation results demonstrate that our trust model reflects the trustworthiness of a service provider more accurately than the weighted feedback model and eBay trust model and thus improves users satisfaction in the open grid environment.

P2P trust management language and certificate chain discovery algorithm

2008, 28(10): 2459-2463.

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Because of the open, distributed and dynamic characteristics of peer to peer (P2P), the security problem has become more difficult. Considering the creation of the trust relationship among entities, a language of trust management based on trust value named LOTOV was proposed. To improve the discovery of the certificates chain effectively, a searching algorithm based on minimal certificategraph using certificate result certificate was designed and implemented. The experiments show the good performance of the approach.

Authentication system scheme based on fingerprint

2008, 28(10): 2464-2466.

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An authentication system scheme based on fingerprint was proposed. The authentication system accomplished mutualauthentication between client and server with the combination of the fingerprint captured by USBKey and the Schnorr protocol. The higher security of system was proved by the analysis of masquerade and reply attacks. At last, the efficiency and cost of system were described and the system was proved to be easily used and maintained.

Data-flow dependency-based trusted recovery method

BAO Bi-Xian Qing-Kai ZENG

2008, 28(10): 2467-2470.

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To effectively recover system states under intrusion situation, an inter-process system recovery method based on data-flow dependency was presented. By realtime monitoring of system calls, abnormal behaviors were detected and damages of the protected system were evaluated. According to the evaluation, the system was recovered. Legal operations were preserved to improve the accuracy and efficiency of recovery. A prototype system was implemented by the method. Experimental results show that the method has better performance in many aspects, such as approximately 10% CPU overhead and reasonable storage expense.

Research on methods of network risk evaluation

Zhi-Cai SHI

2008, 28(10): 2471-2473.

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In order to evaluate the network risk, Hidden Markov random procedure was adopted as analysis means. The output of intrusion detection systems (called alarm events) was used as the processed objects. The Hidden Markov Model (HMM) to describe the state transform of the attacked host system was constructed. The calculation method of the risk coefficient for host systems was given. The risk coefficients for host systems were simply added to obtain the quantitive evaluation of the risk for whole network. The experiments justify that the proposed method is effective.

Trustworthiness of single hop link in wireless sensor network

Peng XIONG Wei ZHANG

2008, 28(10): 2474-2477.

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To overcome a variety of attacks, a novel solution was proposed. The solution is to establish a trusted relation between all neighboring nodes while avoiding untrustworthy nodes during the route discovery process so as to resist DoS-style flooding attacks. This scheme was described in detail. The extensive simulation results indicate clearly that this scheme can resist DoS in wireless sensor network, and its additional overhead is reasonably low.

Improved key-management scheme for wireless sensor networks

Ni CHEN Jian-bo YAO Guang-jun WEN

2008, 28(10): 2478-2480.

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This paper proposed an improved matrix key-distribution scheme for wireless sensor networks. This scheme can delete and update key information with the network topology changes to avoid key information to be revealed. Also, based on the clustered structure, this scheme can reduce communication，computation and key storage overhead, which can solve the problem that each sensor node has limited resource. Comparison and simulation results show that the proposed scheme has higher network security and lower key storage overhead than most of the existing key management schemes.

Intrusion detection model for RFID system based on immune network

Jian-Hua GUO Hai-Dong YANG Fei-Qi DENG

2008, 28(10): 2481-2484.

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It is very hard to develop encryption technology used in cheap Radio Frequency Identification (RFID) tags. In this paper, intrusion detection, as a new methodology, was adopted to create security model for RFID system. By analyzing typical security attacks on RFID systems, and based on artificial immune network, a solution to extract intrusion characteristics and to identify intrusion was proposed. A self-adaptive intrusion detection model for RFID system was designed. The model can enhance the defense capabilities of RFID systems by cooperating with encryption technology, but has no need to amend the technical standards of RFID. Stimulation results prove that the mistake rate and miss rate of the model are fairly low.

Research of distributed and autonomous computer forensics system

2008, 28(10): 2485-2487.

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Currently, most of computer forensics systems are not real-time, and often cause communicational bottleneck. In order to overcome the shortages, a distributed and autonomous computer forensics system was presented. By using the autonomous forensics node, the system could obtain real-time evidence dynamically as soon as network intrusions took place，in which the evidence could be saved in a safe way in time. This way of autonomous forensics could optimize system performance. Experimental result shows that the system can capture the authentic and valid electronic evidence, and has high capability of fault tolerance.

Curve watermarking technique for protecting copyright of digital maps

ZENG Hua-Fei HU Yong-Jian

2008, 28(10): 2488-2491.

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In order to protect the copyright of digital maps, a curvebased watermarking technique for fingerprinting digital maps was proposed. First the embeddable sample points were selected according to their curvatures, and then the spread spectrum based watermark sequence (also called fingerprint sequence) was embedded into the coordinates of the embeddable sample points. To achieve high quality watermarked curve and robust watermark, the Bezier segments were used to reconstruct the watermarked curve. Our watermarked curve suffers smaller embedding distortions and is robust against common geometrical distortions (e.g., translation, rotation, and scaling), collusions, and printingscaling attacks.

Program anomaly detecting approach based on behaviors analysis

[中]罗亚丽 [英]LUO Ya-Li

2008, 28(10): 2492-2494.

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For the purpose of protecting system resource, process behaviors anomaly at runtime was analyzed and summarized, and a program anomaly detection approach was put forward based on behaviors analysis. By setting checkpoints on running system, API hook under usermode was used to detect process behaviors on operating resources, and Bayes algorithm was used to estimate the validity of program behaviors. An alarm would be given when detecting anomaly.

Detection techniques of format-string vulnerabilities in binary files

Long-Jie ZHANG Xiao-Fang XIE Sheng-Zhi YUAN

2008, 28(10): 2495-2498.

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Current detection techniques are mostly limited to the source code level, and research on the binary files is few. Based on the stack pointer and the argument pointer of the formatstring, the attacking principles of formatstring vulnerabilities were researched. A new method to detect formatstring vulnerabilities in binary files was brought forward. By analyzing the method that the model adopted, the particular means and processes to construct the attacking codes were presented. In order to improve the effectiveness of the detection, the attacking code constructions for different systems were studied. At last, an example was given to demonstrate the validity of the detection model.

Input-output model for enterprise energy-consuming unit based on improved resource allocating networks

2008, 28(10): 2499-2502.

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According to the necessity for researching the input-output model of enterprise complex energy-consuming unit, the modeling method for energy-consuming unit based on improved Resource Allocating Network (RAN) was researched. In view of the existing problems of traditional resource allocating networks, a design method for RAN based on rough set and orthogonal least square (OLS) was proposed. Firstly, rough set was applied to intelligent data analysis for extracting typical characteristics from the training samples, and then OLS was used to select best centers as the hidden layer nodes. The simulation results show that the presented modeling method has the advantages of simple network structure, high convergence rate and better generalization ability, etc.

Complex-exponential Fourier neuronal networkand its hidden-neuron growing algorithm

Yu-Nong Zhang Qing-Dan Zeng Xiu-Chun Xiao Xiao-Hua Jiang A-Jin Zou

2008, 28(10): 2503-2506.

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Based on the approximation theory of Fourier-series working in square integrable space, a Fourier neuronal network was constructed by using activation functions of the complex exponential form. Then a weightsdirectdetermination method was derived to decide the neuralnetwork weights immediately, which remedied the weaknesses of conventional BP neural networks such as small convergence rate, easily converging to local minimum and possibly lengthy or oscillatory learning process. A hidden-neurons-growing algorithm was presented to adjust the neural-network structure adaptively. Theoretical analysis and simulation results substantiate further that the presented Fourier neural network and algorithm could have good properties of high-precision learning, noise-suppressing and discontinuous-function approximating.

Dynamic task assignment algorithm based on multi-criteria

2008, 28(10): 2507-2509.

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The present task assignment algorithms consider quite fixed factors and less of extendibility and flexibility. In view of these flaws, a dynamic task assignment algorithms based on multicriteria was proposed. The algorithm is not only more precise to the task participants for track and analysis of real-time situation, but also more balanced to the task assignment. The detailed task allocation formalization was given. The extendibility of the algorithm is strengthened because of the independence among each appraisal target. Moreover, timer was used to realize push and pull task assignment mechanism and strengthen the flexibility. The method not only makes the users to choose work item independently according to their interests, but also makes the system run well while no user choosing the task item. Therefore, the humanity of the task assignment system was strengthened.

Methods of conception soft-and operation in cloud model

2008, 28(10): 2510-1512.

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On account of the importance of the conception soft-and operation in the cloud models as artificial intelligence with uncertainty, two soft-and operation methods to compute the conception were introduced, namely, projection mapping and neural network soft-and. The drops created by cloud models were mapped to new universe of discourse and immediately the X-term cloud generation was used to gain the results of soft-and by the former method. In the later method, case based reasoning was combined with neural network, and through training and learning, the certainty level was predicted finally. The experiments testify that the two conception soft-and methods provide valid and fixed ways for executing the conception of soft-and operation.

Algorithm for learning centre of single class based on k-means and semi-supervised mechanism

2008, 28(10): 2513-2516.

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A new algorithm named "single-means" was presented to improve the centre estimation of the object class when a hybrid data set had unknown k value and feature of accumulating to centre. Based on that k-means algorithm was equivalent to Expectation Maximum (EM) algorithm on a special hybrid Gaussian model, it was proved that given a data set generated by the above Gaussian model, the true centre of the object Gaussian distribution could be converged by a new algorithm. The new algorithm was applied in learning the centre of single text class. The experiment shows that given a small labeled text set, the new algorithm can get a better centre, and is robust on sparse data set and that with great variance.

Multi-objective optimization algorithm with combined strategy based on Pareto optimal and neural network

2008, 28(10): 2517-2520.

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Current multi-objective evolutionary algorithms cannot solve the problems of nonanalytic arithmetic objective functions. With mixed strategy based on evolutionary algorithm and neural network, a novel method to deal with this kind of problem was proposed. Firstly, by training on historical data with neural network, the objective function could be replaced by feasible neural network model. Then, evolutionary computation could be followed by embedding the given neural network model in multi-objective evolutionary algorithm. The given method was applied to the problem of proportion blending. The experimental results show that the proposed approach can solve problems better than other traditional methods.

Improved discrete PSO algorithm and its application in winner determination problem

Zhen WANG Yang Yi

2008, 28(10): 2521-2524.

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A kind of discrete Particle Swarm Optimization (PSO) algorithm named NDPSO was proposed for extending the classic PSO model to solve the discrete optimization problems with high effectiveness and stability. The concept of comparison with probability was also introduced based on NDPSO, and then the stochastic repairing operator was constructed for heuristic search to solve the Winner Determination Problem (WDP) in combinatory auction. The experimental results show that NDPSO has great advantages in both success rate and convergence speed compared with other discrete PSO algorithms and genetic algorithm.

Adaptive interactive genetic algorithms with grey for fitness of evolutionary individuals

2008, 28(10): 2525-2528.

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It is necessary to enhance the performance of interactive genetic algorithms in order to apply it to complicated optimization problems successfully. An adaptive interactive genetic algorithm with grey for fitness of evolutionary individuals was proposed. The fitness uncertainty of evolutionary individuals was measured and expressed by grey. Through analyzing these fitness intervals, information reflecting the distribution of an evolutionary population was abstracted. Based on these, the probabilities of crossover and mutation operation of an evolutionary individual were presented. The proposed algorithm was applied to a fashion evolutionary design system. The results show that it can find many satisfactory solutions per generation.

Scoring matching approach: Learning high order Markov random fields

Xiao-lei LU Fu-rong WANG Ben-xiong HUANG

2008, 28(10): 2529-2532.

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Traditional Markov Random Field (MRF) models have two inherent limitations that are low order property of pixel neighborhoods and selecting parameters by hand. In this paper, we adopted a new machine learning method of score matching and get a group of parameters of high order MRF models by learning from training image data. We demonstrated the capabilities of the learning MRF models by applying them to image denoising according to Bayesian rule. Imaging denoising experiments show that our denoising algorithm can produce excellent result in the Peak Signal-to-Noise Ratios (PSNR) and subjective visual effect. Thus, our learning method is effective.

A fast algorithm for mining frequent subgraphs

Wu Jia 吴甲

2008, 28(10): 2533-2536.

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An algorithm for mining frequent subgraphs based on associated matrix was proposed. By normalizing the associated matrix of the graph, the computational cost on verifying the isomorphism of the subgraphs was effectively reduced. Based on the depth-first searching method, all the frequent subgraphs could be searched by adding edges progressively. Experimental results show that the algorithm has higher speed and better stability than other similar ones.

Comparison of XML compression techniques

Sheng Zhang Xiao-ling Bao

2008, 28(10): 2537-2540.

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XML is a de facto standard for exchanging and presenting information on the Web. However, XML data is also recognized as verbosity since it heavily inflates the data size due to the repeated tags and structures. The data verbosity problem gives rise to many challenges of conventional query processing and data exchange. The hindrance is more apparent in bandwidth- and memory-limited devices. Compression techniques are the important way to overcome the verbosity problem. Multifarious XML-conscious compression methods were collected, and six XML-conscious compression technologies were compared and analyzed in terms of compression ratio, compression and decompression times, memory consumption, and query performance. Their advantages and shortcomings were discussed, and then further work of XML-conscious compression was pointed out.

An efficient similarity search for multivariate time series

2008, 28(10): 2541-2543.

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In order to efficiently perform similarity search for Multivariate Time Series （MTS）datasets, a distance-based index structure (Dbis) for similarity search was presented. The dimension of MTS database was reduced firstly by Principal Component Analysis (PCA). The principal component of MTS was parted by cluster, and a MTS item was selected as reference point from each partition. The MTS items in each partition were transformed into a single dimensional space based on their similarity with respect to a reference MTS item. This allowed the MTS items to be indexed by using a B+-tree structure. An extended Frobenius norm (Eros) was used to compare the similarity between MTS items. Several experiments on a financial MTS database were performed. The results show the effectiveness of Dbis.

Synchronization and replication model in mobile environment

Lisheng Chen Fei-yue Ye

2008, 28(10): 2544-2547.

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Focused on the conflict avoidance and reconciliation problem, a new model of synchronization and replication was proposed. The mobile client cached data with two different granularities. Adopting the mode of "Subscribe-Cancel-Subscribe", it provided customization caching data. Two synchronization strategies were put forward. Client qualified timestamp was used as the swap strategy to solve the Web content conflict and the pretreatment mode before synchronization to reduce the upload data when the mobile client synchronized with server. The combination of priority and transaction cooperation was done to solve the database conflict. The two methods resolved the issue of the data conflict for this model.

Study of similar graph containment search and index

Jin-Tao LV Li Xue-Ming

2008, 28(10): 2548-2552.

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Based on profound analysis and conclusion of several typical indexing strategies towards traditional search, the unique characteristics of similar graph containment search was discussed and a coverage and support based frequent pattern filtering approach for constructing index for this kind of search was proposed as well. Experimental results show this approach is effective.

Distributed query optimization model based on data grid

2008, 28(10): 2553-2557.

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The disparate and geographically distributed data sources in ITS (Intelligent Transportation System) can be integrated using distributed computing technologies such as data grid. The real challenge involved in such data integration is in the design and development of the distributed query processing engine. Generally speaking, distributed query processing and optimization are carried out in three distinct phases: determination of single node plan, generation of parallel plan, and optimal node selection for plan execution. As considering the three phases in isolation leads to suboptimal plans, a new distributed query optimization model was proposed to integrate all the three phases of the query optimization and take all the parameters in the query optimization into account including effective memory, processing speed, tolerance ability of data transportation, etc.

A novel mapping method for image semantics and visual features

YANG Jun JiCheng WANG danjun XING

2008, 28(10): 2558-2560.

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Establishing a mapping relationship between image visual features and semantics can be used to reduce "semantic gap". A novel mapping method for image semantics and visual features was presented. In this method, image semantic information could be captured by adding users relevance feedback, and then a decision table of visual features and semantics was constructed. Knowledge reduction of rough set theory was used to reduce the redundant visual features according to semantics, by doing that a mapping relationship between image visual features and its semantics was established. The experimental results indicate that amount of visual features irrelevant to image semantics can be reduced greatly, the complexity and cost of semantic classification are reduced and the accuracy of classification is better.

MSCR-tree: A spatial index for electronic map on mobile device

2008, 28(10): 2561-2564.

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It should be considered to support the multiscale property when displaying map and the limited computational resource of devices when designing the electronic map application on embedded devices. The conventional spatial index does not support these two features. A new spatial index called MSCR-tree (Multi-Scale Compressed Hilbert R-tree) was proposed in this paper. This new structure provided higher searching efficiency by using data compression and linearization of spatial elements. The experiment shows the MSCR-tree index effectively improves the searching performance and space usage rate.

High-dimensional indexing structure based on γ splitting strategy

WANG Shu-E SUN Jing-Guang

2008, 28(10): 2565-2568.

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An effective index structure was proposed for high-dimensional data spaces: compact pyramid tree. The basic idea is to divide the data space first into 2d pyramids sharing the center point of the space as a top. Its basic philosophy is: the data invalid in low-dimensional spaces are usually invalid in high-dimensional spaces. In the process of spatial division, the γ division strategy was used to carry out the data compression. It reduced the index structure, and overcame the pyramid technologys shortcomings. The construction method and inquiry algorithm of pyramid tree were given. The experiments prove that compact pyramid technology is an effective spatial division strategy, and has good performance in highdimensional skew space.

Overlay multicast routing algorithm with minimum overlay cost

2008, 28(10): 2569-2572.

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Compared with IP multicast, overlay multicast usually consumes more underlying network resources. Therefore, utilizing the underlying network resources effectively has some practical significance when constructing the multicast delivery tree based on overlay network. The concept of overlay cost was proposed, and the overlay multicast routing problem was defined to find a degree and delay constrained spanning tree with the minimum overlay cost for an undirected complete graph. The goal of the solution was to satisfy the applications requirements and the end hosts performance needs, and to make the consumption of underlying network resources minimum at the same time. A heuristic genetic algorithm for this problem was given, and the simulation results verify the effectiveness of the algorithm.

Dependability enhancement of mission-critical wireless networks by message scheduling

Wei JIANG XIONG Guang-ze

2008, 28(10): 2573-2576.

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Dependable requirements, like real-time and security, pose great challenges for missioncritical wireless networks, whereas existing message scheduling algorithms disregard security factors. In this paper, a SecurityAware Message Scheduling (SAMS for short) was proposed to maximize the security profit of a group of missioncritical messages without sacrificing security-ritical and time-critical constraints. Simulation results show the efficiency and robustness of SAMS.

Survivability model for vehicular Ad-Hoc network based on Markov chain

2008, 28(10): 2577-2579.

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According to the characteristics and application of Vehicle Ad-Hoc Network (VANET), the factors in the survivability of VANET were defined, and then the services, threats, and strategies of VANET were analyzed. The model of average survivability based on Markov chain was developed. Finally, the correctness verification work of the model was also done by simulations. Both the theory and simulation results show that keeping basic services and preventing serious threats can efficiently enhance the survivability of VANET.

SCP2P: A self-adaptive peer-to-peer model based on peer characteristics

2008, 28(10): 2580-2583.

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Peers have their own characteristics in peer-to-peer network. In the past research, the characteristics were either ignored completely or considered simply. A self-adaptive P2P model based on peer characteristics was proposed by fully using peer characteristics. In the model, peers organize clusters based on their characteristics. The model, in terms of the requirement mode, can adjust connections among peers and peer status, as well as cluster scale.

Table-based routing protocol in wireless sensor networks

2008, 28(10): 2584-2586.

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Routing is one of the key problems in Wireless Sensor Network (WSN). A routing protocol based on routing table named SPBT (Sensor protocol based on routing table) was put forward. In the routing protocol, route tables were used to simplify the data transmission process to save energy, and the strategy for equilibrium of using energy and route optimization was used to establish routes. In order to improve the reliability of data transmission, the strategy of trace-back was adopted. In simulation, the table-based protocol was compared with the protocol SPIN. The results show that the protocol SPBT can use energy effectively with equilibrium of using energy and shortened delay.

Study on the fast handover performance of MIPv6 in 802.11

lee blake

2008, 28(10): 2587-2589.

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The fast handover performance of MIPv6 in Wireless Local Area Network (WLAN) was studied. In order to optimize the handover performance, a method appropriately improved upon the Fast Handovers for Mobile IPv6 (FMIPv6) protocol was proposed. In the method, the handover latency and data loss were greatly reduced through the combination of HMIPv6 and fast router bulletin. This algorithm was simulated in an open source Network Simulator 2 (NS-2).

Algorithm for detecting module structure in complex networks based on node type

Shi Wei Zheng Zhao Gui-xiang Xue

2008, 28(10): 2590-2593.

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A new algorithm based on node type named SW was proposed for detecting modules in complex network efficiently. Fist, Simulated Annealing (SA) algorithm was adopted for initial partition of the network. Second, the nodes were classified into different types and the network was further partitioned according to node type until it reached optimization. Experimental results show that SW algorithm can detect the modules efficiently.

Clustering hierarchy tree routing algorithm based on LEACH

Chun-Yan SONG Hua-Zhong ZHANG

2008, 28(10): 2594-2596.

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Considering the characteristics of sensor nodes' limited energy and limited transmission radius, the clustering hierarchy tree routing algorithm based on LEACH was proposed. In cluster construction stage, the optimal candidate cluster heads would become the final cluster heads, which guaranteed the distance between any two heads was far enough and neither of them was in the same area of radius, so the cluster heads were uniformly distributed in the network. In the intercluster communication, cluster heads form a hierarchical tree and the root was Base Station (BS), which reduced the energy consumption of direct data transmission from the head to BS, thereby prolonging the life cycle of the network.

Research on improving TCP performance over wireless links by adaptive FEC

Wang Jian-zhong

2008, 28(10): 2597-2599.

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An adaptive algorithm for end-to-end Forward Error Correction (FEC) to improve TCP performance over wireless links was proposed. A new TCP (TCP-ARS) combining this algorithm with ReedSolomon code was realized. TCP-ARS can reconstruct the lost packets by packet level adaptive FEC. The simulation results are promising and show in different scenarios that the throughput can be significantly improved by adding adaptive FEC to TCP.

Search in social networks using MCMC algorithm

2008, 28(10): 2600-2603.

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Experiments and theoretical analysis demonstrate that short path exist in social networks, and people can search a target in a few steps. Greedy routing in social networks was explored. An MCMC algorithm was given to embed a given shortcut graph into a one or two dimensional grid. This algorithm was realityoriented and the coordinate system was used only for the computation of network distance. The algorithm was tested using artificially generated data (graphs generated according to the ideal model in one and two dimensions)as well as real social network data. The result is pretty satisfactory: the success rate of inquiry is high and the mean step length of success inquiry is short.

On-line algorithm of loose competitive caching

Zhao-Quan CAI

2008, 28(10): 2604-2607.

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In response to a sequence of requests for files, where each file has a specified size and retrieval cost, the total size of each file in cache was maintained at some specified k so as to minimize the total retrieval cost. A simple deterministic on-line algorithm was proposed. In this algorithm, many well-known paging and weighted caching strategies were generalized, and the retrieval cost was either insignificant or at most a constant (independent of k) times the optimum value for most k. This helps explain why competition ratios of many on-line paging algorithms have been typically observed to be constant in practice.

A program understanding approach for stripped binary code

Liarod Romangol Dawu Gu Haining Lu

2008, 28(10): 2608-2612.

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The stripped binary form software is a typical object that software analysis and program understanding activity often deal with. Traditional analysis and comprehension models based on source code or debug symbol information are often useless when handling this kind of software for lack of information. A comprehension approach for stripped binary code was proposed. The analysis object was transformed to runtime process and the process information was imported. Then the program's action feature was imported using the external behavior and interface as the supplementary information, the feature was mapped to binary code. Finally, program slicing and debugging techniques were used to analyze program. The approach has access to more information for software analysis and program understanding and reduces the complexity, thus solves the information shortage and model building problem when analyzing stripped binary code.

Research of data processing and filtration in RFID middleware

2008, 28(10): 2613-2615.

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As the data collection part of the platform of Radio Frequency Identification (RFID) system test, RFID data collection middleware is mainly responsible for test data collection and lowlevel data processing and filtration. We firstly presented its architecture. Secondly, we emphatically introduced its data processing and filtration module, analyzed the logical mapping engine, and presented three kinds of RFID data filters in detail: duplication elimination filter, event filter and TagID filter.

Mainframe application transition to SOA environment using J2CA

2008, 28(10): 2616-2618.

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Mainframe application is widely used in the SOA environment. By discussing the Adapt transition method and adapterprovided service interface to transit the mainframe 3270 applications to the SOA environment, the mainframe application usage in the SOA environment was proposed. In the case study, how to use J2CA architecture to fulfill the mainframe 3270 applications transition to the SOA environment was analyzed. Some parts of core codes were also provided.

Web application research based on extended Struts framework

Bing LIU

2008, 28(10): 2619-2621.

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Struts framework has no good presentation layer flexibility. Through analyzing its characteristics, XSL was combined with Struts by mighty conversion function in XSLT to improve the view of Struts. An improved model XStruts was proposed. This model was the extension of Struts. It separated business logic from presentation and supported XML and XSL. It could support many types of clients. This model was easier to maintain and extend. Finally, a typical Web application, online bookstore system, was designed and implemented using XStruts.

Active contour model based on multi-swarm particle swarm optimization

2008, 28(10): 2622-2624.

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Searching for the object's concavities of active contour model (Snake model) is a dynamic optimization problem. Due to its complexity, the traditional active contour model and single particle swarm optimization algorithm converge slowly and easily converge to local optima. Aiming at the above problems, multi-swarm PSO algorithm was proposed to apply in active contour models for the sake of expanding the control point of the searching area and optimizing convergence speed. In this algorithm, every control point was corresponding to one swarm. Subswarms worked together via information sharing. The results obtained by the multi-swarm PSO algorithm have been compared with that of single PSO algorithm and the conventional method. Experimental results show that the proposed algorithm is more efficient.

Research on Edge Detection Algorithm based on Odd Gabor Filter

xiaoxing gao li Cao

2008, 28(10): 2625-2627.

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Using canny edge detection operator, it is set 2 thresholds by users. Results of edge detection vary widely when we use the same threshold on the different images. This limits the practical application of Canny operator. To solve this problem, this paper presents an edge detection using odd Gabor filter. This method used non-maximum inhibition, and then used high and low threshold to detect the edge of the images. The experimental results show this algorithm not only overcome the defects of Canny algorithm, but also effectively wipe off the pseudo-edge of the image.

Fast image segmentation algorithm based on region competition with level set

Lin-Juan Wang Xi-Li Wang

2008, 28(10): 2628-2632.

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An adaptive variational image segmentation model based on Bayesian and region competition was presented. Level set method was used to describe the plane curves and partitioned regions, and the energy function was obtained based on Bayesian region statistical information. Then, a new fast partial different equation for curve evolution was deduced to implement unambiguous image segmentation by region competition. The model can extract multi-class objects simultaneously with fast evolving speed and high segmentation precision. Also, it is easy to integrate other image information such as texture and shape into this model. Besides, the energy function and curve evolution equations are independent so that we can choose different probability functions to describe various types of images. The experimental results show that it is a fast, effective and novel image segmentation algorithm.

Fast concave object extraction algorithm based on graph cuts and GVF Snake

Li-Li TIAN Min GUO Qiu-ping XU

2008, 28(10): 2633-2635.

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Combining Gradient Vector Flow (GVF) Snake model with graph cuts theory, a fast concave object extraction algorithm was proposed. First the initial contour was deformed with the graph cuts algorithm, which could put the initial contour in the valid approach region of the GVF field to extract nonconcave part of the object boundary. Then the active contour was input to Snake model and began its evolvement to concave part of the object boundary. Experimental results show that the algorithm can converge to concave object boundary fast and accurately.

Efficient method for object contour extractionbased on probability distribution image

Cheng LU Dong-jian HE

2008, 28(10): 2636-2638.

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Focusing on object contour extraction technology that had the most significant impact on the process of image analysis, an efficient method was proposed for object contour extraction based on probability distribution. First the foreground object was detected and its hue feature was used to build an object probability model. With this model, the probability distribution image was calculated on the whole image for the object. Finally, the contour was obtained from the probability distribution image directly. After testing the method using 2330 continuous images containing moving object, the results suggest that the method can work efficiently. It takes 20ms to 30ms to process a true color image of 640×480 pixels, and the contours extracted are very clear and accurate.

A new improved OPTA thinning algorithm

2008, 28(10): 2639-2642.

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The improved OPTA thinning algorithm for fingerprint images was studied deeply. A new improved OPTA thinning algorithm was proposed to solve the problem that there is much spur in the afterthinning fingerprint images. In the new algorithm, various thinning orders were used for various line-angle and curvedirection, the remove templates were modified, and the reserve templates were improved. Through lots of experiments, the algorithm has been proved to be a better thinning algorithm, which inherits the advantages and can significantly reduce the spur in the thinning process.

An adaptive filter based on images' entropy

Wang Xue-Zhong 王学忠 Xiao Bin

2008, 28(10): 2643-2644.

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An adaptive filter to remove mixed Gaussian noise and impulse noise of the corrupted images based on their minimum entropies was proposed. The proposed filter calculated the noise rate of the corrupted image based on the minimum local entropy, and utilized the noise rate to determine the size of filter windows and the number of pixels to be brushed off in the filter windows of Alphatrimmed mean filter, and then used the average of leaved pixels' gray as the output of the filter. The performance of the proposed filter was evaluated by experiments. Experimental results show that the superiority of this filter including the ability of removing noises and that of preserving the partial details of images in comparison with some existing methods (median filter and mean filter), and this filter is an adaptive Alpha-trimmed mean filter.

Ant colony algorithm in airline seat inventory optimization

Wen Zhang

2008, 28(10): 2645-2647.

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Airline seat inventory optimization is a very profitable tool for airline. Current researches are focused on network seat inventory optimization, which has high complication of combination of the ODF (Origin, Destination, Fare) and seat number. Due to the large number of decision variables, traditional optimization models are hard to compute. Although some LP approximation methods of traditional models improve their practical applicability, they still take long time to compute and have high complexity when network is large. We used ant colony algorithm to solve network seat inventory optimization in this paper. It is shown that ant colony algorithm can solve problem quickly and gain good results, and it is easy to implement.

Fault diagnosis for ship sewage treatment equipment based on clustering support vector machine

2008, 28(10): 2648-2651.

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To solve the problems of condition monitoring and fault diagnosis for ship sewage treatment equipment, a fault diagnosis model based on clustering Support Vector Machines (SVM) was proposed. In the model, the neural network clustering algorithm was used to realize clustering analysis and to obtain the normal subspaces and the abnormal subspaces in the condition monitoring sample space. Then, to the abnormal subspaces, the multi-classification SVM based on binary tree architecture was designed to carry out the fault diagnosis and recognition. Compared with the traditional SVM learning algorithms, the proposed algorithm avoided the blind classification and improved the classification performance in some extent. The model was applied to a ship sewage treatment equipment to train and exam the measured samples. Experiment results show this method has good generalization and expendibility.

Simulated annealing particle swarm algorithm applied in new traffic control model

2008, 28(10): 2652-2654.

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The city transportation system is a random and complicated giant system. To acquire good traffic efficiency, a new adaptive Particle Swarm Optimization (PSO) algorithm based on simulated annealing temperature (SATPSO) was proposed, and a new harmony control signal model of city transportation was given. Then SATPSO was used in the model. The emulation results show that the algorithm can overcome the defects of the original PSO sinking into the local optimal, and has good convergence and stability. The model is feasible and effective.

New heuristic algorithm for channel assignment in cellular mobile systems

2008, 28(10): 2655-2657.

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In the algorithm for channel assignment problems in cellular mobile systems, sequential ordering algorithm assigns channels to cells according to its assignment difficulties. This algorithm is simple and fast, but it can easily be trapped in the sequential cycling. A new heuristic algorithm based on MAX-MIN ant system algorithm was proposed. It could solve the above problem by choosing a cell by its selecting probability, and avoid stagnation by justifying convergence factor and then reset pheromone trails to find a better sequential ordering. In the procedure of testing Philadephia problem, our algorithm is closer to the theoretical lower bound, and its convergence time is shorter than other ant algorithms with the same solution quality.

Cellular automaton model for mixing traffic in two-lane system with period boundary condition

QIAN Yong-Sheng

2008, 28(10): 2658-2660.

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Based on the analysis of the existing classical cellular automaton model of traffic flow, considering the characteristic of part of expressways without differences between running lane and passing lane, we demarcated the parameters such as length of the cellar automaton, operation speed, random slow mechanism and the max speed etc, set up the vehicle's generating function and vehicle changing lane regulation, and established Cellular Automaton (CA) model for mixing traffic in twolane system with period boundary condition. Then we analyzed the relation among three parameters of traffic flow through computer simulation, and the impact of the occupation rate of large-scale freight vehicles on traffic flow. We compared the spacetime evolution figure with density changing under the same occupation of large-scale vehicles. The result shows that the occupation rate of large-scale freight vehicles has little influence on the speed of mixed traffic flow in the situation that the expressways have no differences between running ways and passing ways. The stochastic deceleration probability of the vehicle plays an important role in the motion state of mixed traffic flow.

Morphology measure and 3D reconstruction of corn leaf based on machine vision

2008, 28(10): 2661-2663.

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A method was proposed to gain the plant configuration information and 3D reconstruction. According to the principles of binocular stereo vision, two images were obtained. By image segmentation technology and edge detection algorithm, leaf edge of each image was extracted. Epipolar line and RGB of color image were applied to match stereo images, then 3D coordinates of the leaf edge were worked out, so the 3D edge of the leaf could be reconstructed. Besides, using the same technique, the surface of the leaf could be reconstructed. According to the point cloud, the distance between any two points could be got. Results of many experiments show that 3D information of corn leaf can easily be reconstructed by this method.

Study on fisheye image correction based on cylinder model

Zhou Hui Luo Fei Li Hui-juan Feng Bing-shu

2008, 28(10): 2664-2666.

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Fisheye lens break the limit on the view field of the ordinary camera, and develop a new path for computer vision research and application. In spite of its advantage in broader view and importance in application, fisheye image has its own distortion. A way to correct the distortion of the whole fisheye image was introduced. A method called equal arc length mapping in cylinder model based on the spherical perspective was proposed to solve the problem of distortion. The specific derivation of the algorithm was also provided. The obtained images prove the effectiveness of the proposed algorithm.

Off-line Chinese signature authentication based on integrated neural networks

Lei Zhang CHEN Xiao-rong CHEN Xiao-zhu

2008, 28(10): 2667-2669.

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To assist the signature specialists, the authentication system for offline Chinese signatures was developed based on a new Integrated Neural Network (INN), which was composed of the modules, namely Feature Distributed Network (FDN), Neutral Networks Classifier (NNC) and Decision Fusional Network (DFN). In the method, a specific classifier was created for each of the signatures，and both training sets were constructed to solve the verification and recognition problems. The proposed method yields satisfactory results on signature verification experiments, and can be used to support human experts to authenticate handwriting signature.

Application research of image fusion in ultrasonic tomography of concrete

2008, 28(10): 2670-2672.

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To comprehensively utilize the inversion results of different parameters, the image fusion algorithm based on wavelet transform was adopted to synthesize the images by straight ray tracing and bend ray tracing. The application example shows that the image fusion can effectively integrate the image information. And the fusion rule can significantly reduce background noise and highlight the defect details, which is suitable for the concrete ultrasonic tomography image.

Fabric defects detection based on frequency domain filtering

Sheng-Qi Guan

2008, 28(10): 2673-2675.

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According to the spectrum of fabric texture and defects, a new method for defect detection was presented. Firstly, on the basis of the fabric texture classification, a spectrum image was derived from the Fast Fourier Transform (FFT). Then, the frequency filter was designed to remove normal texture information, and the acquired reconstruction images were segmented into many subwindows, in which variances were calculated as characteristics. Lastly, the characteristics were compared with the standard threshold to determine whether there were defects. Experimental results show that this method is valid, and the detection average accuracy is over 90%.

Rough terrain identification based on random texture analysis

2008, 28(10): 2676-2678.

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According to the characteristics of slope which block autonomous vehicle navigation under cross-country environment, textures analysis was used to compute the slant of slope. The radial competition method was presented for extracting random texture elements that could reflect the sizes of texture elements. Then based on the positions of center distributions of the same size textures, nesting clustering and linear method were used to fit the tilt and continental distance with varying weight was used to compute gradients. Slants of surfaces could be received by the calibration experiment between gradients and slants. Experimental results show that the method can compute the tilt and slant of the surface effectively and the computing error is close to the estimate error of human vision. Furthermore, the method is little affected by gray scale.

New camera pose estimation method based on adaptive particle filter

Liu Wei

2008, 28(10): 2679-2682.

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A new adaptive particle filter based camera pose estimation method was implemented. The noise variance between two adjacent frames to update the prediction model dynamically, and then interior points statistical method was used to calculate the weight. After normalizing the weight, the position and orientation of the camera were calculated. Experimental results show that this method improves the robustness and practicability of markerbased systems.

Reversible data hiding based on fingerprint image characteristics

2008, 28(10): 2683-2685.

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A lossless data hiding technique was proposed using histogram pair based on fingerprint characteristics. It was used in an online bank pension distribution system for fingerprint recognition and fragile watermarking. The fingerprint characteristics of mass fingerprint image were analyzed. It was concluded that there was max number in pixel value equal to 0 and 255 from histogram of fingerprint image, and there was maximum fall between 0 or 255 and near pixel value. The values of 0 or 255 and near pixel were compressed, and then hidden data was embedded into 0 or 255. Experiment shows that it can get better Peak Signal-to-Noise Ratio (PSNR) and enough data embedding capacity to normal application (over 5000 bits).

Architecture design of embedded operating system based on heterogeneous dual-core processor

Jian-Chun JIANG

2008, 28(10): 2686-2689.

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The master-slave embedded operating system is widely used on heterogeneous multiprocessor. The architecture and communication protocol is heterogeneous, so it makes the realization and communication handling complicated. Through analyzing the structural characteristics of heterogeneous dualcore processor, a symmetric communication operating system architecture was proposed based on uniprocessor operating system, and resolves the problem how to make full use of the shared memory to communicate and to improve the efficiency of communication between processors in heterogeneous dualcore processor. This architecture operating system is used successfully on TI OMAP5910.

Simulation research on LS RISC microprocessor

2008, 28(10): 2690-2692.

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The system structure simulation in microprocessor has already become the main means of design-space-exploration (DSE) and optimizing systematic designing plan. Through research of LS RISC system structure modeling and analyses of the advanced simulation technology home and abroad, interpretive instruction set simulator LR-sim of LS RISC was designed and implemented. LR-sim was composed of decoder, pipeline, instruction attempter automatic machine, clockdriven model, resource manager and cachememory system, in consideration of simulating efficiency while carrying on one grade of modeling of detailed grain size clock. A large number of tests show that this simulator helps to optimize the wire layout of the hardware, shortens hardware design cycle, and has stronger portability, operability and expansibility.

Dual-core DMA communication between DSP and FPGA in panoramic imaging system based on reverse wave analysis

Zhi-Hui XIONG Li-Dong CHEN Mao-Jun ZHANG Le LI Wei-Dong BAO Shu-Ren TAN

2008, 28(10): 2693-2695.

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A dual-core DMA communication method between DSP and FPGA based on reverse wave analysis was proposed. In high definition and real-time dualcore embedded systems for catadioptric omnidirectional imaging, the dual-core DMA communication method was used to provide high speed panoramic data communication between DSP and FPGA. Reverse engineering methods were applied to perform reverse wave analysis on traditional DMA operations, and dual-core DMA communication was accomplished according to the results of wave analysis. Experiments indicate that the proposed dual-core DMA communication method provides a maximum data transmission speed between DSP and FPGA at 4.704Gbps (i.e. 588MBps).

High-throughput Reed-Solomon decoder

2008, 28(10): 2696-2700.

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Reed-Solomon (RS) coding is one of the most widely applied channel coding schemes. Due to the increasing speed and throughput of communication systems, highthroughput RScoded systems are intensively required. A novel highthroughput RS decoder was derived and proposed. Inversionfree BerlekampMassey, Chien, and Forney algorithms were adopted in the decoder. The proposed decoder featured a new efficient multiplexing pipeline, which provided considerable throughputperformance improvement. As shown in implementation results, the proposed decoder renders significant throughput enhancement regarding hardware complexity, compared with other known RS decoders.

Application of group and expansion code in test data compression

Wang Bao-Qing Hua-guo Liang

2008, 28(10): 2701-2703.

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A scheme of test data compression based on the Group and Expansion Code (GEC) was presented to reduce compression data of System-on-a-Chip (SoC). It is a variabletovariable code based on encoding both 0s run and 1s run, and the code word consists of marked bit, prefix and tail. Due to the characteristics of GEC, which lies in its ability to double capacity of every group, it can compress test data efficiently. Theoretical analysis and experimental results show that the proposed scheme can provide a higher compression efficiency than FDR and has a better adaptability to various test sets.

Design of feedback shift register based on chaos

2008, 28(10): 2704-2706.

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The key stream generated from Line Feedback Shift Register (LFSR) has short period and does not suit encrypting plentiful information. At the same time, chaotic sequences are prone to become short periodic ones because of the restriction of computational precision of computers. Aiming at remedying these inadequacies, a new design of the Feedback Shift Register (FSR) based on chaotic maps was put forward. Through simulation and analysis, the favorable performances of the binary sequences got from our method are evaluated.

Design and implementation of keyboard input method for handwritten Chinese characters

2008, 28(10): 2707-2710.

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A new handwritten Chinese character keyboard input method was designed, and an algorithm of generating strokes intelligently based on fast fuzzy matching was presented. In this method, a Chinese character was simulated on the keyboard by a key list of feature points including uppoints, twistpoints, middlepoints and downpoints of each stroke. By constructing a netlike search space of strokes, a key list was converted to a set of stroke lists, so that the keyboard input of the Chinese character was achieved. It is unnecessary to memorize the keys stricken when the user inputs Chinese character into the computer.

Construct theory of hierarchical functional networks and its application in multiple numerical integral

Xiu-Xi WEI Tao-Shen LI

2008, 28(10): 2711-2714.

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The universal approximation properties of hierarchical functional network were verified. Using this feature, the structure and learning algorithm of hierarchical functional network were used to obtain numerical approximation in the multiple numerical integral. Simulation results show that this method for numerical calculation of multiple numerical integrals is practical and effective, and has good computation precision.

Uncertainty clustering algorithm and its application to intrusion detection system

hu lu

2008, 28(10): 2715-2717.

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Clustering algorithm is an unsupervised machine learning method, which has important applications in the fields of intrusion detection and pattern recognition. Based on the two new proposed verdict criterions, a new possibility fuzzy clustering algorithm was presented based on the uncertainty membership, to realize selflearning and detection based on intrusion dataset. The experimental results based on the datum of KDDCUP99 demonstrate that the algorithm possesses higher detection rate and lower misuse detection rate.

Modeling method of multivariate statistical control chart for small-batch manufacturing process quality

2008, 28(10): 2718-2720.

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Based on the study of multivariate statistical process quality control chart and small-batch manufacturing process, a kind of synthetical modeling method was put forward to deal with multivariate statistical process for small-batch manufacturing. Practical application and emulational instance show that this modeling method can make the best use of the obtained data, build control model dynamically, consequently resolve the problem of lacking modeling data in small-batch manufacturing process.

PPR based similarity search for gas monitoring data

Hua Zhao

2008, 28(10): 2721.

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A Piecewise Polynomial Representation (PPR) based similarity search approach for time series data in coal well gas monitoring was proposed. For experiments, sample data were real gas monitoring data obtained from Yuhua Coal Mine, and evaluation criterions were information loss and mean search efficiency. Experimental results compared with the performance of Discrete Fourier Transform (DFT) based approach and Discrete Wavelet Transform (DWT) based approach show: in the condition of the same compress rate, values of information loss of PPR, DFT and DWT based approaches are very close to each other; Whereas, mean search efficiency of PPR based approach is 32% higher than that of DFT based approach, and 34% higher than that of DWT based approach respectively. Therefore, PPR based approach is more suitable for similarity search of gas monitoring data.

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