Table of Content

01 December 2011, Volume 31 Issue 12

Previous Issue    Next Issue

Network and communications

Incentive strategy based on Bayesian game model in wireless multi-hop network

XU Li CHEN Xin-yu CHEN Zhi-de

2011, 31(12):  3169-3173. 

Asbtract ( )   PDF (984KB) ( )  

References | Related Articles | Metrics

The enhancement of nodes intelligence causes more applications for the wireless multi-hop networks. The security problem also becomes more crucial. In order to prevent the adverse effects of the selfish nodes or malicious nodes, this paper proposes a cross-layer mechanism based on the game theory. A Bayesian game model is developed for the information sharing between the physical layer and the link layer. Apply the Bayesian game model to derive and analyze the mutual information among nodes and form an effective mutual supervision incentive for the node cooperation. The effectiveness of the proposed Bayesian game model is shown through careful case studies and comprehensive computer simulation.

Random access packet-based strategy for TD-SCDMA trunking system

JIANG Qing XU Ze-wen TANG Hong LIU Zhang-mao WU Xiang-lin

2011, 31(12):  3174-3176. 

Asbtract ( )   PDF (622KB) ( )  

References | Related Articles | Metrics

Concerning the collision and access failure which are very likely to occur when the intensity of the users’ access increases, a random access packetbased strategy was proposed. The users were divided into several groups according to the strategy; certain subframes formed a superframe to enable different users to send Uplink Synchronization Code (SYNCUL) to the corresponding subframe of superframe when the users needed random access information, and based on it, priority was set for the users from different groups. Compared with the general strategy, packetbased strategy has greatly improved the success rate of the users’ access, and grouping based on priority was adopted to ensure a higher success rate for advanced users. The theoretical analysis and simulation results show that the proposed packetbased strategy can significantly improve the system Quality of Service (QoS) and could be an effective measurement for decreasing the probability of collision in random access.

Two radios multi-channel MAC protocol in cognitive radio networks

QIAN Yu-le LI Yun

2011, 31(12):  3177-3180. 

Asbtract ( )   PDF (643KB) ( )  

References | Related Articles | Metrics

In the cognitive radio networks, the main functions of MAC protocols include channel sensing, channel selection and access, the detection time and transmission time has the important influence on network performance. In dynamic wireless network environment, how to reasonably distribute detection time and transmission time is a challenge. A two radios multi-channel distributed MAC(TM-MAC) protocol are proposed, which is not necessary to detect channels before node transmit data. Node can detect the spectrum resource while other nodes transmit data. Then, the node can transmit data use the idle spectrum resource. A model is built to analyze the throughput of TM-MAC under the saturation condition. The analysis results show that TM-MAC improves the throughput in cognitive networks.

Spectrum usage prediction based on chaotic neural network model for cognitive radio system

XIAN Yyong-ju YANG Yue XU Chang-biao ZHENG Xiang-yu

2011, 31(12):  3181-3183. 

Asbtract ( )   PDF (531KB) ( )  

References | Related Articles | Metrics

In order to improve spectrum usage in Cognitive Radio System (CRS), and reduce channel switching frequency, a new prediction mechanism was designed, which was used chaotic neural network to analyze and predict the last time of channel status. Simulation results show that the prediction accuracy can reach 90%, thus the effectivess of this new prediction mechanism was proved.

Improved M-virtual scanning algorithm for road surveillance

SU Pan-lan CHEN Liang-yin ZHANG Jing-yu YUAN Ping

2011, 31(12):  3187-3190. 

Asbtract ( )   PDF (601KB) ( )  

References | Related Articles | Metrics

VIrtual Scanning Algorithm（VISA) is unable to fully take advantage of the number of nodes, in order to prolong the network lifetime, it must be built on the basis of dense nodes deployment which makes the time for finding average target increase. Therefore, based on low dutycycle Wireless Sensor Network (WSN) by combining the ideology of virtual scan wave, the Multiple VIrtual Scan Algorithm (M-VISA) was proposed for road surveillance. This algorithm adopted the way of fixing points, deploying the same location with multinodes to let the nodes to be worked in order and in batches, hence, the network lifetime could be greatly extended. Simulation result demonstrates that M-VISA can prolong network lifetime by 180% when compared with VISA, improving the network performance effectively.

Network coding-incremental relay mechanism in wireless cooperative communication system

SUN Wen-sheng CHEN An-hui

2011, 31(12):  3191-3194. 

Asbtract ( )   PDF (593KB) ( )  

Related Articles | Metrics

The existing network coding applied to wireless communication system uses a fixed way to relay. Therefore, a new cooperation mechanism was proposed: Network CodingIncremental Relay (NC-IR). The relay node decided whether to forward according to the two users’ sending status of the direct passing path. That is, if both of the direct passing paths or neither of them were successful while sending users’ data, the relay node did not forward data, and if only one of the direct passing path were successful while sending users’ data, the relaying node forwarded the data by network coding. The simulation shows that this cooperation mechanism saves a lot of time slot, power and bandwidth resources without affecting the system performance.

High-speed multicast congestion control based on population ecology

MA Hai-yuan MENG Xiang-ru MA Zhi-qiang ZHOU Jing ZHUANG Xu-chun

2011, 31(12):  3195-3199. 

Asbtract ( )   PDF (814KB) ( )  

Related Articles | Metrics

The existing TCP multicast congestion control mechanisms do not have speed smoothness, Round-Trip Time (RTT)-fairness, and high efficiency in highspeed networks. To solve these inherent disadvantages derived from TCP, an Adaptive High-Speed Multicast (AHSM) congestion control mechanism was proposed based on population ecology theory. The new mechanism estimated the bottleneck bandwidth and the rate of background traffic at each receiver. Then the estimated values were used in population ecology model to calculate requested service rate. The receiver with lowest requested service rate was selected as representative to control the sending rate via feedbacks. The simulation results show that the new mechanism has speed smoothness and RTT-fairness, it also has high transmission efficiency in high-speed networks. It can share bandwidth with unicast flow in both low and high-speed networks.

Coverage problem of directional sensors in wireless sensor networks

ZHOU Yun ZHAN Hua-wei

2011, 31(12):  3200-3203. 

Asbtract ( )   PDF (633KB) ( )  

Related Articles | Metrics

Coverage problem is one of the most fundamental problems in wireless sensor networks since it reflects the sensing quality. The present studys mostly concentrates in Omni-directional sensors which is not suitable in many applications such as video surveillance systems consisting of directional video sensors. This paper present a new (k,ω)-angle coverage problem which study directional sensors deployment. The goal is to deploy minimal number of sensors to k-angle cover all the targets. It present a greedy algorithm to solve this problem. For this algorithm, it define three contribution functions to determine the location to deploy sensor. The proposed method greedily selects a maximal contribution location to deploy a sensor until the entire targets are k-angle covered. Simulation results exhibit the characteristic and performance of this algorithm.

New method of calculating coverage and connectivity rate

LI Chao-liang XING Xiao-fei LIU Yue-hua

2011, 31(12):  3204-3206. 

Asbtract ( )   PDF (435KB) ( )  

Related Articles | Metrics

Deploying sensor nodes’ has to meet certain coverage and connectivity in the energy constrained wireless sensor networks. Concerning this, a new square regionbased coverage and connectivity probability computational method was proposed in this paper. The new method can not only depict the relations among coverage rate, connectivity rate, the number of nodes, the sensing (communication) range of nodes and the size of network, but also calculate the number of sensor nodes scattered for maintaining certain coverage rate and connectivity rate. The simulation results show that the errorrate of deployment is less than the value obtained from the theoretical analysis.

Design of shortened LDPC codes based on IEEE802.16e protocol without short cycles

CUI Yuan-yuan XU Rong-qing PAN Xin-yan WANG Yu-jie GUAN Li WANG Bin-bin

2011, 31(12):  3207-3209. 

Asbtract ( )   PDF (468KB) ( )  

Related Articles | Metrics

The shortened LDPC codes based on the current IEEE802.16e Standard, has plenty of small girth. In order to resolve this problem, this paper presents a new scheme of designing the shortened LDPC codes. In the proposed scheme, the design has modified the sub-parity check matrix under the frame of the IEEE802.16e Standard. The proposed check matrix with the spreading factor (zf=48) is constructed with quasi-cyclic matrix method and finite geometry method. Moreover, parity check points was searched the node degree in the way of synchronous sequential, the proposed sub- parity check matrix has minor girth-6 and no girth-4. The results of simulation in the AWGN channels show that the improved short code with the code rate approaching to 0.5, can fast encode as excellent as the IEEE802.16e protocol contains，moreover, a good BER performance of the proposed code is 1.1dB more than the Shannon limit of this channel.

Hybrid BitTorrent traffic detection

LI Lin-qing YANG Zhe ZHU Yan-qin

2011, 31(12):  3210-3214. 

Asbtract ( )   PDF (788KB) ( )  

Related Articles | Metrics

Peer-to-peer (P2P) applications generate a large volume of traffic and seriously affect quality of normal network services. Accurate and real-time identification of P2P traffic is important for network management. A hybrid approach consists of three sub-methods was proposed to identify BitTorrent (BT) traffic. It applied application signatures to identify unencrypted traffic. And for those encrypted flows, message-based method according to the features of the message stream encryption (MSE) protocol was proposed. And a pre-identification method based on signaling analysis was applied to predict BT flows and distinguish them even at the first packet with SYN flag. And some modified Vuze clients were used to label BT traffic in real traffic traces, which made high accuracy benchmark datasets to evaluate the hybrid approach. The results illustrate its effectiveness, especially for those un- or semi- established flows, which have no obvious signatures or flow statistics.

Distributed weighted node localization algorithm based on Euclidean correction

2011, 31(12):  3215-3218. 

Asbtract ( )   PDF (597KB) ( )  

Related Articles | Metrics

The traditional Multi-Dimensional Scaling (MDS) algorithm adopts multihop distance to replace direct distance, resulting in low accuracy of the local network and large localization error in irregular network. Relative to the existing algorithms， the paper introduced the Euclidean algorithm to generate accurate multihop distance between nodes, and used weighting mechanism to improve the coefficient of stress. The simulation results show that in low connectivity rectangle network and C-shape network localization, this method achieves better performance.

Handover algorithm based on cluster mobile node

LV Sha-sha SUN Jian-wei JIA Jun-ying YU Bo

2011, 31(12):  3219-3222. 

Asbtract ( )   PDF (660KB) ( )  

Related Articles | Metrics

Handover procedure of modern cellular wireless networks depends on IP-based technology. IETF Proxy Mobile IPv6 (PMIPv6) protocol guarantees the Quality of Service (Qos) in fast handover moving while it does not support realtime communications between two mobile nodes. Therefore Cluster Mobile Node (CMN) algorithm was proposed to reduce handover delay in the system by applied Media Independent Handover (MIH) Technology. Also, the algorithm extended PMIPv6 protocol with an Aggregated Proxy Binding Update (A-PBU) scheme in the paper. Finally, the network model and mobile model were simulated and the effectiveness of handover delay was analyzed. Quantitative results show a significant reduction in handover delay compared with the original handover algorithm.

Peak-to-average power ratio reduction algorithm based on correlation between candidates of iteration partial transmitted sequence

GUO Min GUO Ya-nan Gan JunNa

2011, 31(12):  3223-3225. 

Asbtract ( )   PDF (617KB) ( )  

Related Articles | Metrics

The Partial Transmitted Sequence (PTS) is an efficient algorithm to solve the problem of high Peak-to-Average Power Ratio (PAPR) in Orthogonal Frequency Division Multiplexing (OFDM),but the basic algorithm of PTS has higher computational complexity. A new algorithm based on Cyclic Iteration PTS (C-IPTS) which is called Correlational Cyclic Iteration PTS(CC-IPTS) was proposed to solve this problem. The proposed algorithm reduced computational complexity by using the relation between adjacent phase factors in Iteration PTS (IPTS), and the correlation of two candidate signals in PTS and cyclic iteration. The simulation shows that CCIPTS can not only improve the PAPR performance,but also reduce computational complexity.

Low complexity partial transmit sequence algorithm and realization on field programmable gate array

LIU Jun-jun YUAN Zhu MA Teng ZHOU Jian-hong

2011, 31(12):  3226-3229. 

Asbtract ( )   PDF (601KB) ( )  

Related Articles | Metrics

The conventional Partial Transmit Sequence (PTS) approaches get high computational complexity and need to transmit side information, which is difficult for hardware implementation. Concerning these problems, this paper proposed an algorithm of using m sequences as phase rotation factors and transferring them by pilot information. The m sequence can reduce the complexity of Field Programmable Gate Array (FPGA) implementation and the pilot transferring phase rotation factor need no side information. The Matlab simulation proves the algorithm is effective. Meanwhile, a Peak-to-Average Power Ratio (PAPR) suppression module was designed to be implemented on FPGA, and the results show that this module not only reduces the complexity of OFDM systems, but also works well in PAPR suppression.

OFDM channel estimation based on DFT decision threshold method

LI Shi-ping LI Xin

2011, 31(12):  3230-3232. 

Asbtract ( )   PDF (431KB) ( )  

Related Articles | Metrics

In Orthogonal Frequency Division Multiplexing (OFDM) systems, the key point is to improve accuracy and reduce complexity of channel estimation algorithm. First, the traditional Discrete Fourier Transform (DFT) channel estimation algorithm was improved. Furthermore, the impact of channel noise was eliminated through the introduction of the decision threshold, and system performance improved, then the improved channel estimation was compared with LS, SVD and DFT estimation. Finally,the Matlab simulation results show that the proposed algorithm can improve the accuracy of channel estimation without increasing the complexity, and then improve the performance of the whole system.

DoA estimation of complex coherent signals based on temporal smoothing and reconstruction of Toeplitz matrix

SUI Wei-wei JING Xiao-rong ZHOU Wei ZHANG Yong-jie

2011, 31(12):  3233-3235. 

Asbtract ( )   PDF (566KB) ( )  

Related Articles | Metrics

Under the condition of coherent multipath environment, the algorithms of temporal smoothing and reconstruction of Toeplitz matrix were adopted respectively to estimate the DoAs (Direction of Arrivals) of complex coherent signals, furthermore these two algorithms were compared through mathematical analysis and computer simulation, and the following conclusion could be obtained: Both of these two algorithms for DoA estimation of complex coherent signals have the effectivity, the performance of algorithm based on reconstruction of Toeplitz matrix is relatively better but it will lose the array aperture, the algorithm based on temporal smoothing will not lose array aperture and can estimate M-1 coherent multi-paths (M is the number of array elements), however, it has a slightly larger calculation load.

Database technology

Attributes reduction method based on limited tolerance relation in incomplete information system

WANG Chao LUO Ke

2011, 31(12):  3236-3239. 

Asbtract ( )   PDF (624KB) ( )  

Related Articles | Metrics

The confirm of core attribute of a decision table is always the base of information reduction. However, most of the previous reduction methods in core attribute were faced to complete information system. Extending the reduction algorithm in core attribute and attribute order to incomplete information system, which used in complete information system, this paper presents a attribute reduction algorithm based on limited tolerance relation in incomplete information system. This method obtains core attribute by constructing a improved discernable matrix of decision table in incomplete information system, sorts the attribute which not belongs to core attribute by ability of affecting classification quality intuitively, in order to ensure the reduction result we get is a relatively minimize reduction. This method shows more feasible and effective in experiment by comparison.

Set-valued ordered information systems under dominance relation

LIN Yao-jin LI Jin-jin LIN Meng-lei

2011, 31(12):  3240-3242. 

Asbtract ( )   PDF (596KB) ( )  

Related Articles | Metrics

Set-valued ordered information systems could be divided into conjunctive/disjunctive set-valued ordered information systems. Through analyzing the limitations of the existing dominance relations in conjunctive/disjunctive set-valued ordered information systems and discussing the unreasonable situations, new dominance relations which could classify objects better were proposed. Based on this, rough set models in conjunctive/disjunctive setvalued ordered information systems were constructed, and the validity of the proposed technique was checked with classical instances.

Decision tree optimization algorithm based on multiscale rough set model

CHEN Jia-jun SU Sjou-bao XU Hua-li

2011, 31(12):  3243-3246. 

Asbtract ( )   PDF (587KB) ( )  

Related Articles | Metrics

Concerning the complicated structure and being sensitive to noise and other problems of decision tree constructed by classical decision tree algorithms, a new decision tree construction algorithm based on multiscale rough set model was proposed. This proposed algorithm introduced the concept of scale variable and scale function, the index of approximate classification accuracy in different scales was used to select test attributes and the holddown factor was put forward to prune the decision tree and removed the noise rules effectively. The results show that decision tree constructed by this algorithm is simple, and has certain degree of antiinterference and can meet the decision accuracy requirements from different users.

Nonlinear discriminant K-means clustering on manifold

GAO Li-pin ZHOU Xue-yan ZHAN Yu-bin

2011, 31(12):  3247-3251. 

Asbtract ( )   PDF (921KB) ( )  

Related Articles | Metrics

In real applications in pattern recognition and computer vison, high dimensional data always lie approximately on a low dimensional manifold. How to improve the performance of clustering algorithm on high dimensional data by using the manifold structure is a research hotspot in machine learning and data mining community. In this paper, a novel clustering algorithm called Nonlinear Discriminant K-means Clustering (NDisKmeans), which has taken the manifold structure of high dimensional into account, is proposed. By introducing the spectracl regularization technology, NDisKmeans first represents the desired low dimensional coordinates as linear combinations of smooth vectors predefined on the data manifold; then maximizes the ratio between inter-clusters scatter and total scatter to cluster the high dimensional data. A convergent iterative procedure is devised to solute the matrix of the combination coefficient and clustering assignment matrix. NDisKmeans overcomes the limilation of linear mapping of DisKmeans algorithm; therefore, it significantly improves the clustering performance. The systematic and extensive experiments on UCI and real world data sets have shown the effectiveness of the proposed NDisKmeans method.

Fuzzy ISODATA clustering algorithm based on gene expression programming

JIANG Dai-hong

2011, 31(12):  3252-3254. 

Asbtract ( )   PDF (460KB) ( )  

Related Articles | Metrics

Concerning the defects of the artificial setting of the categories number, the sensitiveness to initial cluster centers and the lack of automatic clustering effects on the ISODATA algorithm, in combination with Gene Expression Programming (GEP) a nested iterative selforganizing fuzzy clustering was formed up. This paper presented a new algorithm: fuzzy ISODATA clustering algorithm based on GEP. This algorithm not only conducted automatic clustering under the condition of no prior knowledge, but also fully used the capability of global optimization of GEP algorithm and soft classification features of ISODATA, which resulted in the increase of the convergence speed and the clustering accuracy. It is verified by simulation and comparative analysis of the practical problems in GIS logistics location.

Airborne multi-sensor management methods based on fuzzy decision tree

ZHANG KUN ZHOU De-yun WANG Qian XU Jie

2011, 31(12):  3255-3257. 

Asbtract ( )   PDF (413KB) ( )  

Related Articles | Metrics

In view of the difficult in management of airborne multi-sensor, a fuzzy decision tree algorithm is applied to multi-sensor intelligent management, combined with operational processes, and combat stage will be merging with the target type, different target attributes is built reasonable. The fuzzy decision trees model are established based on target type, then the airborne multi-sensor management model is established. Finally, the simulation results show that the method can compose battlefield objectives and tactical effectively, complete airborne multi-sensor management rapidly, and the method is reasonable and effective.

Semantic integration method and research for XML data based on domain ontology and relational model

LI Hua-yu OUYANG Chun-ping XU Jiu-yun

2011, 31(12):  3258-3263. 

Asbtract ( )   PDF (1060KB) ( )  

Related Articles | Metrics

Due to lack of sufficient semantic information, it is difficult to interoperate among XML data files with different schemas. Facing the needs to integrate XML data in the field of Well-Engineering, this paper proposes a model-independent semantic integration method for XML data using domain global ontology. This method builds semantic mapping between domain ontology and paths of XML schema to shielding the pattern differences; then, XML data is stored as relational data using model-mapping method; finally, the SPARQL query will be rewriting into SQL statements to realize semantic query. By semantic annotating to XML schema and using relational database to store and query XML date, this method solves the semantic integration for domain XML data effectively.

Wikipedia-based focused crawling with page segmentation

XIONG Zhong-yang SHI Yan ZHANG Yu-fang

2011, 31(12):  3264-3267. 

Asbtract ( )   PDF (628KB) ( )  

Related Articles | Metrics

Against shortcomings and limitations of traditional focused crawling methods, a wikipedia-based focused crawling with page segmentation was proposed. It set up topic vector by category tree and topic descriptive document of wikipedia, which described topic; introduced page segmentation after downloading a web page, to filter noise nodes; took block relevance into consideration when computing the priority of candidate links，making up for limited information of anchor text; and validated whether different detailed degree of topic description would effect the performance of focused crawling or not, via changing the size of topic vector space. Experimental results show that this method is effective and scalable, and within a limited degree, the more detailed the topic description, the more related to the topic the collected web pages are.

Network User Identify On Feature Weighting Naive Bayes Classification Algorithm

LIU Lei CHEN Xing-shu YIN Xue-yuan DUAN Yi LV Zhao

2011, 31(12):  3268-3270. 

Asbtract ( )   PDF (475KB) ( )  

Related Articles | Metrics

Based on the access logs of network users, Feature Weighting Naive Bayes Classification(FWNBC) algorithm is used to identify users. Firstly, the data acquisition system based on WinPcap framework was used to collect the access logs of network users, characteristics are counted from five aspects by analyzing these access logs, and then selected after filtering, at last the FWNBC algorithm is used to identify the 3300 samples, and the recognition rate reached 85.73%.The experiment results show that this algorithm is effective to identify the identity of network users.

Automatic annotation of auxiliary words usage in rule-based Chinese language

HAN Ying-jie ZAN Hong-ying ZHANG Kun-li CAI Yu-mei

2011, 31(12):  3271-3274. 

Asbtract ( )   PDF (597KB) ( )  

Related Articles | Metrics

Existing results of auxiliary word are difficult to use in the automatic annotation of natural language processing. Based on the auxiliary words knowledge base, rule-based method is used in automatic annotation of auxiliary words usage. Contrast to the results of test, it shows that refining, extension and adjusting the matching order of the rules can promote the precision and recall effectively. It is also benefit for improve the quality of Chinese Corpus, deepen the processing depth, and reduce the artificial work.

Method for elimination of redundant sentences in automatic abstraction

CHEN Chuan-peng YANG Yao-ke

2011, 31(12):  3275-3277. 

Asbtract ( )   PDF (412KB) ( )  

Related Articles | Metrics

To solve the problem of information redundancy in automatic abstraction, this paper proposed a method for eliminating redundant sentences in automatic abstraction. Firstly, similarity of words was defined based on TongYiCi CiLin. And then, correspondence between topic words and subject sentence was established based on the similarity of words, the similarity of subject sentence was got based on the theory of Hamming distance in encoding theory, and high similarity sentences were reduced by threshold. The experimental results show that the method greatly improves the accuracy of abstraction.

Dynamic multi-granularity locking mechanism based on transaction deadline

ZHAO Yue-hua HAN Shao-cong

2011, 31(12):  3278-3280. 

Asbtract ( )   PDF (603KB) ( )  

Related Articles | Metrics

Multi-granularity locking mechanism improves the concurrency of the database system. But in real-time database, the traditional multi-granularity locking mechanism meets serious challenge for the real-time demand of its transaction processing. In this paper, considering multi-granularity locking mechanism and the transaction deadline, a dynamic multi-granularity locking mechanism based on transaction deadline is proposed. The transaction conflicts level are determined by transaction deadline, and when the conflicts reach or drop to a certain level, the locking granularity is adjusted accortding to current locking granularity. Through simulations, the expermental results show that this mechanism can not only reduce transaction confilicts, but also reduce the miss ratio and restart ratio of transaction, improve transaction concurrency and real-time.

Application of WCF distributed framework to mobile data synchronization

LIU Li-zhi WU Yun-tao

2011, 31(12):  3281-3284. 

Asbtract ( )   PDF (656KB) ( )  

Related Articles | Metrics

Using remote data access and merge copy to synchronize data exists problems of data security and unsuitable with complex network structure. Synchronization service realizes data synchronization by the way of reconstructing synchronization components, so the server synchronization components and the client synchronization components can be deployed separately. To encapsulate server components by WCF, the server components provide data synchronization service as an application service layer individually and the problems of data security and unsuitable with complex network structure caused by RDA or merge copy can be resolved by this way. Incremental data synchronization can be applied by customizing data adapters and data conflicts can be resolved by data synchronization service conflict management mechanism using server priority or client priority, so a perfect mobile data synchronization solution based on WCF distributed framework is given by this paper.

Similarity measurement of time-series data with different granularities

SHAO Xiao-shasha HAO Wen-ning JIN Da-wei WANG Ying

2011, 31(12):  3285-3287. 

Asbtract ( )   PDF (498KB) ( )  

Related Articles | Metrics

Most of the existing similarity measurement, based on Euclidean distance, cannot be applied directly and effectively to similarity matching of the timeseries with different granularities. This paper proposed a new similarity measure based on the sample of the corresponding D-value. It firstly expounded the definition of the time-series with different granularities, and defined the sample of the corresponding D-value; secondly it put forward the similarity matching algorithm; finally, the experimental results prove that the algorithm can effectively measure the similarity of time-series with multiple granularities.

Artificial intelligence

Shuffled frog leaping algorithm based on immune evolutionary particle swarm optimization

LI Zuo-yong ZHANG Zheng-jian YU Chun-xue

2011, 31(12):  3288-3291. 

Asbtract ( )   PDF (583KB) ( )  

Related Articles | Metrics

A new shuffled frog leaping algorithm based on immune evolutionary particle swarm optimization was proposed in order to avoid premature convergence and to improve the precision of solution by using basic Shuffled Frog Leaping Algorithm (SFLA). The proposed algorithm integrated the global searching idea in the Particle Swarm Optimization (PSO) into SFLA, to pursue the information of two optimal solutions in the sub-swarm and the whole-swarm simultaneously, so as to search thoroughly near by the space gap of the worst solution, and also integrated the immune evolutionary algorithm into SFLA making immune evolutionary iterative computation to the optimal solution in the whole-swarm, so as to use the information of optimal solution fully. This algorithm can not only get free from trapping into local optimum and be close to the global optimal solution with higher precision, but also speeds up the convergence. Calculation results show that the Immune Evolutionary Particle Swarm Optimization-Shuffled Frog Leaping Algorithm (IEPSO-SFLA) has better optimal searching ability and stability as well as faster convergence than those of basic SFLA.

Hybrid feature selection methods based on D-score and support vector machine

XIE Juan-ying LEI Jin-hu XIE Wei-xin GAO Xin-bo

2011, 31(12):  3292-3296. 

Asbtract ( )   PDF (801KB) ( )  

Related Articles | Metrics

As a criterion of feature selection, F-score does not consider the influence of the different measuring dimensions on the importance of different features. To evaluate the discrimination of features between classes, a new criterion called D-score was presented. This D-score criterion not only has the property as the improved F-score in measuring the discrimination between more than two sets of real numbers, but also is not influenced by different measurement units for features when measuring their discriminability. D-score was used as a criterion to measure the importance of a feature, and Sequential Forward Search (SFS) strategy, Sequential Forward Floating Search (SFFS) strategy, and Sequential Backward Floating Search (SBFS) strategy were, respectively, adopted to select features, while Support Vector Machine (SVM) was used as the classification tool, so that three new hybrid feature selection methods were proposed. The three new hybrid feature selection methods combined the advantages of Filter methods and Wrapper methods where SVM played the role to evaluate the classification capacity of the selected subset of features via the classification accuracy, and leaded the feature selection procedure. These three new hybrid feature selection methods were tested on nine datasets from UCI machine learning repository and compared with the corresponding algorithms with F-score as criterion of the discriminability of features. The experimental results show that D-score outperforms F-score in evaluating the discrimination of features, and can be used to implement the dimension reduction without compromising the classification capacity of datasets.

Sequential minimal optimization algorithm for bilateral-weighted fuzzy support vector machine

LI Yan YANG Xiao-wei

2011, 31(12):  3297-3301. 

Asbtract ( )   PDF (752KB) ( )  

Related Articles | Metrics

High computational complexity limits the applications of the Bilateral-Weighted Fuzzy Support Vector Machine (BW-FSVM) model in practical classification problems. In this paper, the Sequential Minimal Optimization (SMO) algorithm,which firstly decomposed the overall Quadratic Program (QP) problem into the smallest possible QP sub-problems and then solved these QP sub-problems analytically, was proposed to reduce the computational complexity of the BW-FSVM model. A set of experiments were conducted on three real world benchmarking datasets and two artificial datasets to test the performance of the SMO algorithm. The results indicate that compared with the traditional interior point algorithm, the SMO algorithm can reduce significantly the computational complexity of the BW-FSVM model without influencing the testing accuracy, and makes it possible for the BW-FSVM model to be applied to practical classification problems with outliers or noises.

Parameter optimization of support vector machine and application based on particle swarm optimization mode search

WANG Xi-bin ZHANG Xiao-ping WANG Han-hu

2011, 31(12):  3302-3304. 

Asbtract ( )   PDF (619KB) ( )  

Related Articles | Metrics

Considering the importance of selecting Kernel parameters, the Particle Swarm Optimization (PSO) model search algorithm was proposed to search optimal parameters. This method combined the global search capability of PSO algorithm and the good local convergence of mode search, that making PSO model search algorithm displays higher performance, and applied to an the practice of agricultural technological project classification. The results of experiment show that this method is not only efficient, but also catches the optimal parameters that have achieved higher accuracy.

Product diffusion study of fast moving consumer goods based on hybrid model of Bass and cellular automata models

ZHANG Yan-fang XIONG Hai-ling

2011, 31(12):  3305-3308. 

Asbtract ( )   PDF (631KB) ( )  

Related Articles | Metrics

The product diffusion of Fast Moving Consumer Goods (FMCG) mainly involves two aspects, the initial purchase and the replacement purchase. The current Bass model has the macro forecast ability about initial purchasers, while the cellular automata model can effectively predict the amount of the replacement purchasers. A hybrid model by learning advantages from the Bass and cellular automata models was proposed to forecast the FMCG diffusion. The mean error of estimation values and real values form 1999 to 2006 is 4.11%, and its fitting degree is 96.7%; the perdiction values are 15%,7%,2% smaller than the real values of Chinese milk sales volumes in 2007,2008,2009 respectively. The experimental results on Chinese milk sales volume verify that the hybrid model is effective and applicable to predict the FMCG product diffusion of Chinese milk sales volumes.

Hierarchical cellular genetic algorithm based on polycentric urban strategy

LU Yu-ming CAI Ye LI Ming

2011, 31(12):  3309-3311. 

Asbtract ( )   PDF (606KB) ( )  

Related Articles | Metrics

In order to improve the accuracy, speed and efficiency of the Hierarchical Cellular Genetic Algorithm (HCGA) in solving complex problem, in this paper, a new polycentric HCGA on the basis of HCGA and with reference to the central city theory of western economics was proposed. The new algorithm chose a few individuals with high fitness in population as the central cities. Individuals around the central city moved towards the center，and the optimal solution was generated from these central cities. The algorithm greatly improves populations diversity and thus the searching efficiency. The numerical simulations show that the improved algorithm is more effective for realizing the global optimization and can avoid premature effectively.

A research of motion control strategy on mobile robot formation

LIANG Jia-hai

2011, 31(12):  3312-3314. 

Asbtract ( )   PDF (463KB) ( )  

Related Articles | Metrics

This paper studied how to achieve the diversity, stability and continuity of formation change for mobile robots，and solved the problem of obstacle and collision avoidance for the robot formation to reach the destination. The basic formation was analyzed and the idea of formation parameterization was presented. Parametric mathematical model was established for the virtual structure of basic formation. Formation alternated between basic formation and derivative formation by adjusting the parameters. Robot motion can be controlled by using behavior fusion method, follow pilot method, artificial potential field method and virtual structure method. The simulation and experimental results show that this strategy not only retains the advantage of stability and rapid formation of virtual structure method but also improves flexibility.

Football position prediction algorithm based on calculation of strong tracking and H∞ filter

YANG Huan-huan YANG Yi-min

2011, 31(12):  3315-3317. 

Asbtract ( )   PDF (364KB) ( )  

Related Articles | Metrics

Robot soccer moves in dynamic environment which exists unknown outside interference. In the process of competition, the soccer often collides with obstacles such as robots, thus causing change of position and direction. Aiming at the above, an algorithm based on calculation of strong tracking filter(STF) and H∞ filter is proposed to predict the position of football. By introducing a time-varying fading factor, it can both improve the tracking ability of state mutation and avoid making assumptions on the interference signals. In the middle size league of robot soccer competition platform, experiments were conducted to verify the effectiveness of the proposed algorithm.

Quantitative player affective modeling based on evolution neural network

WANG Xiao-ling LIANG Hui DUAN Yun-fei TANG Ning-jiu

2011, 31(12):  3318-3320. 

Asbtract ( )   PDF (628KB) ( )  

Related Articles | Metrics

Player modeling is an important research area in game design field. Foreign scholars have proposed the modeling method based on statistics, but this kind of method needed to build the mathematic model subjectively, which is lack of objectivity. This paper proposed a quantitative method, which was based on the evolution neural network, to build the nonlinear model between game data and the players emotional preferences. The experimental results show that the model constructed by this method is of high efficiency and accuracy.

Survey on Chinese text sentiment analysis

WEI Wei XIANG Yang CHEN Qian

2011, 31(12):  3321-3323. 

Asbtract ( )   PDF (566KB) ( )  

Related Articles | Metrics

The sentiment analysis has aroused the interest of many researchers in recent years，since the subjective texts are useful for many applications. Sentiment analysis is to mine and analyze the subjective text, aiming to acquire valuable knowledge and information. This paper surveyed the status of the art of Chinese sentiment analysis. Firstly, the technique was introduced in detail, according to different granularity levels, namely word, sentence, and document; and the research of product review and news review were presented respectively. Then evaluation and corpus for Chinese text sentiment analysis were introduced. The difficulty and trend of Chinese text sentiment analysis were concluded finally. This paper focuses on the major methods and key technologies in this field, making detailed analysis and comparison.

Advanced computing

Inference of mass ontology based on cloud computing

Qu Zhen-xin YU Chuan-ming

2011, 31(12):  3324-3326. 

Asbtract ( )   PDF (395KB) ( )  

Related Articles | Metrics

To solve the problem of inference on mass ontology, a new algorithm was proposed based on cloud computing platform. Ontology schema was transformed into graph, inference strategy was designed accordingly. Inference algorithm was designed based on the computing model of Map/Reduce. After one time iteration, mass ontology could be inferred in the course of Map. Later, duplicated triples were eliminated in the course of Reduce. The experimental results show that inference of one hundred million triples costs less than four minutes. The algorithm is effective.

Parallel matrix multiplication based on MPI+CUDA asynchronous model

LIU Qing-kun MA Ming-wei YAN Wei-chun

2011, 31(12):  3327-3330. 

Asbtract ( )   PDF (655KB) ( )  

Related Articles | Metrics

Matrix multiplication plays an important role in scientific computing. Different structural models can improve the performance of parallel matrix multiplication. In the existing MPI+CUDA synchronization model, the host-side need enter the waiting state and cannot continue to work until the device completes the task, which obviously wastes time. Concerning this question, a parallel matrix multiplication based on MPI+CUDA asynchronous model was proposed. This model prevented host-sides entering into the waiting state, and used CUDA-stream technology to solve the problem of data bulk over GPU memory. By analyzing the speedup ratio and efficiency of the asynchronous model, the experimental results show that MPI+CUDA parallel programming obviously promotes parallel efficiency and large-scale matrix multiplication’s speed，which exerts the advantages of the distributional memory between the nodes and the share memory in the node. It is an effective and feasible parallel strategy.

Research and Design of Parallel Parsing and Layouting Method for Embedded Browser

YANG Liu-hui LEI Hang GUO Wen-sheng

2011, 31(12):  3331-3333. 

Asbtract ( )   PDF (475KB) ( )  

Related Articles | Metrics

A parallel parsing and layout method for embedded browser was introduced in this paper. By putting the controlling and layout into the master thread, loading resources and parsing into the slave thread, this method paralleled the serial parsing and layout process for Web pages. To solve the problem of the browser’s slow response to users, the message scheduling method for the browser combined with thread scheduling model in Operating System (OS) was also designed. The feasibility of the method is verified and the speed of rendering the first screen to users is improved by 4%-17% costing less than 64MB memory according to the testing cases.

Multicore digital signal processor implementation of normalized cross-correlation image matching

LIU Yi-fei ZHANG Xu-ming DING Ming-yue

2011, 31(12):  3334-3336. 

Asbtract ( )   PDF (445KB) ( )  

Related Articles | Metrics

In order to meet the high requirements for the performance of processor in image processing, the multicore Digital Signal Processor (DSP) system of high performance and low consumption was adopted. Based on template image in the source image pixel by pixel searching and calculating the relativity in the Normalized Cross-Correlation (NCC) algorithm，the search area was divided into six parts and made each core of six core DSP of TMS320C6472 parallel search and calculate the relativity of the respective area. NCC image matching algorithm was implemented on six core DSP of TMS320C6472 using source images and template images of different sizes which were stored in different memory types. The experimental results show that the multicore DSP inherits such advantages of single DSP as high speed signal and image processing and it can realize multicore parallel processing through inter-core task distribution according to different algorithms. For the NCC image matching algorithm, the performance of six core DSP is almost six times better than a single DSP performance and has improved in comparison to the performance of PC while the image size is relatively large.

Information security

Improved SVM co-training based intrusion detection

WU Shu-yue YU Jie FAN Xiao-ping

2011, 31(12):  3337-3339. 

Asbtract ( )   PDF (467KB) ( )  

Related Articles | Metrics

In this paper, a Support Vector Machine (SVM) co-training based method with variation factors to detect network intrusion was proposed. It made full use of the large amount of unlabeled data, and increased the detection accuracy and stability by co-training two classifiers. It further introduced variation factors among multiple iterations to decrease the possibility of effect reduction due to over-learning. The simulation results show that the proposed method is 7.72% more accurate than the traditional SVM method, and it depends less on the training dataset and test dataset.

Design and implementation of secret communication based on layered service provider

ZHONG Yan WANG Peng

2011, 31(12):  3340-3342. 

Asbtract ( )   PDF (610KB) ( )  

Related Articles | Metrics

Most conventional software can not implement communication protection by modifying compiled binary code. Concerning this problem, this paper proposed a general LSP-based confidential communication model. The model introduces the optimization of the linear Hash table to store communication information, and realizes communication protection function on LSP layer by converted Winsock network model and hooked system function. The experimental results show that the proposed model can efficiently realize confidential communication between client and server.

Robustness analysis of unstructured P2P botnet

XU Xiao-dong Jian-guo CHENG ZHU Shi-rui

2011, 31(12):  3343-3345. 

Asbtract ( )   PDF (458KB) ( )  

Related Articles | Metrics

Constant improvement of botnet structure has caused great threat to network security, so it is very important to study the inherent characteristics of botnet structure to defense this kind of attack. This paper simulated the unstructured P2P botnet from the perspective of complex network, then proposed metrics and applied the theory of complex centrality to analyze the robustness of the unstructured P2P botnet when it encountered nodes failure. The experimental results demonstrate that the unstructured P2P botnet displays high robustness when it encounters random nodes failure, but its robustness drops quickly when it encounters central nodes failure.

Intermittent control of nonlinear systems with time-varying delay

2011, 31(12):  3346-3349. 

Asbtract ( )   PDF (541KB) ( )  

Related Articles | Metrics

Time-varying delay widely exists in nonlinear systems. This paper investigated the intermittent control problem of nonlinear systems with time-varying delay and its applications in chaotic secure communications. The authors proposed an intermittent control scheme, and analyzed its correctness theoretically. Moreover, a theorem was also given to determine the corresponding parameters in the controller. According to the proposed theorem, the synchronization of two chaotic Chua’s circuits can be achieved by designing intermittent controller. The method was applied to chaotic secure communications, and the sender’s signal could be recovered well at the receiving end after the synchronization was achieved. This also shows that the proposed method has some engineering applications.

Graphics and image technology

Simultaneous segmentation and bias correction for MR image based on local region fitting model

REN Ge CAO Xing-qin YANG Yong

2011, 31(12):  3350-3352. 

Asbtract ( )   PDF (622KB) ( )  

Related Articles | Metrics

Intensity inhomogeneity often exists in Magnetic Resonance (MR) images, which is due to the smooth bias field caused by the deficiency of the device. Traditional intensity-based segmentation algorithms often assume the uniform intensity belonging to the object and background, respectively. Therefore, these algorithms fail to successfully segment image with intensity inhomogeneity. This paper proposed a local region fitting model for simultaneous segmentation and bias correction. The model is built based on the intensity property in the local region to build an energy function with respect to the intensity, bias field function and the region indicating function. Then, this energy function was optimized with respect to the intensity, bias field and the indicating function, respectively. The segmentation and bias field estimation would be conducted simultaneously finally. The experimental results on the real MR brain images demonstrate the advantages of the proposed method over variational level set approach.

Algorithm of contours splicing based on OBB projection transformation

2011, 31(12):  3353-3356. 

Asbtract ( )   PDF (652KB) ( )  

Related Articles | Metrics

When reconstructing three-dimensional model based on contours splicing, due to the complexity of spliced object, any kind of mosaic method can not cover all cases. Therefore, on the premise of one-to-one splicing, this paper proposed an algorithm of contours splicing based on Oriented Bounding Box (OBB) projection transformation: First, judged the convexity-concavity of the vertices of polygon. The concave vertex was projected, to the corresponding convex hull; second, calculated the oriented bounding box of convex hull and rotated and translated the rectangular to the axis, calculated the rectangular inner concatenated ellipse; Third, projected the each vertex of polygon to the ellipse, spliced the contours based on these projection vertex. Finally, sought for the correspondence relation between vertices of adjacent contours, and used the actual coordinates to establish the original model of three-dimensional reconstruction.

Image median filtering algorithm based on grey absolute relation

YANG Fang-fang ZHANG You-hui WANG Zhi-wei LI Jun-hong DONG Rui

2011, 31(12):  3357-3359. 

Asbtract ( )   PDF (669KB) ( )  

Related Articles | Metrics

This paper integrated the characteristics of the grey absolute relation with the advantages of the median filter to combine the pixels within the n×n template into two sequences, where n is an odd number that is greater than or equal to 3. Then, the characteristics of the grey absolute relation were used to determine the similarity between the two sequences. Finally, the degree of similarity was adopted to determine whether the current pixel is noise or not, and then the value of median filter was used to replace the noise one. The experimental results show that this algorithm has better filtering effect than the standard median filter method and other filtering methods while keepings more details of the original image.

New objects detection system based on mixture Gaussian model

JIN Guang-zhi SHI Lin-suo BAI Xiang-feng TENG Ming-chun

2011, 31(12):  3360-3362. 

Asbtract ( )   PDF (660KB) ( )  

Related Articles | Metrics

The traditional mixture Gaussian models need much computation and have difficulty in detecting the moving objects under a non-stationary background. Therefore，a new object detection system based on mixture Gaussian model was proposed. An equal weight initial strategy was introduced in the system to improve the results of video detection in the initial stage. Meanwhile, the operation times of variance were reduced by a model matching method based to the linear mean deviation, the calculation of the models was reduced effectively, and the survival ability of model in complex background was enhanced by adding a disturbance information processing module. The experimental results show that the new system can accurately detect multiple moving objects in the initial video stage, and can fast amalgamate the entering and remaining objects into the background. Besides, it can effectively overcome the disturbance of nonstationary background. The research clearly shows that the accuracy and robustness of system are significantly improved.

Quick approach of multi-threshold Otsu method for image segmentation

LIU Yan ZHAO Ying-liang

2011, 31(12):  3363-3365. 

Asbtract ( )   PDF (466KB) ( )  

Related Articles | Metrics

Otsu has been widely used because of its simplicity in calculation and good segmentation result. And many scholars have put forward multi-threshold Otsu method to make it more useful in more complex pictures. But this multi-threshold Otsu method is of low efficiency and time consuming. Concerning this shortage, this paper made histogram intervals first, and then the rapid dichotomy was used to seek for the threshold in the interval. The improvement in this paper can maintain good segmentation result and save lots of time. The experiments show that the algorithm is effective.

Parallel architecture for lifting-based 2DDWT algorithm

TIAN Bao-hua LI Bao-feng

2011, 31(12):  3366-3369. 

Asbtract ( )   PDF (565KB) ( )  

Related Articles | Metrics

A 2x2 parallel architecture for the lifting-based 2D Discrete Wavelet Transform (2DDWT) is presented. The architecture exploits three inherent parallelisms in 2DDWT - row parallel, column parallel and row-column parallel to improve the execution speed and reduce the memory requirement. The proposal takes N2/4+N/2+1 clocks to transform a N×N image while only 3N internal memory is required. The architecture is verified by simulation and implemented in a StratixⅡFPGA

Skin segmentation based on Real Adaboost

YU Yi-min HUANG Ting-hui SANG Tao

2011, 31(12):  3370-3372. 

Asbtract ( )   PDF (593KB) ( )  

Related Articles | Metrics

This paper proposed a method for skin segmentation based on the similarity of skin-tone given by strengthened classifier which constructed via Real AdaBoost algorithm and dynamic threshold.Based on the clustering property of skin-tone distribution in YCrCb chrominance space, a set of weak classifiers in Look-Up-Table (LUT) type using circle-like features was trained via Real AdaBoost to form a strengthened classifier. Firstly, gray scale images indicated the skin-tone similarity of the pixels was created by processing the images with the strengthened classifier. Then skin segmentation was implemented according to the dynamic threshold selected through Da-Jing method. The experimental results show that the strengthened classifier has an outstanding ability for describing the distribution of skin-tone color in the YCrCb space. The method is robust, and efficient.

Image segmentation of maximum cross entropy based on histogram reconstruction

CAO Jian-nong

2011, 31(12):  3373-3377. 

Asbtract ( )   PDF (805KB) ( )  

Related Articles | Metrics

Concerning the thresholds selection in image segmentation, this paper proposed a method that used dynamic threshold to divide the histogram of original image into two new independent histograms. The two new histograms correspond to two fictitious images whose sizes are the same to original one，and pixels of the same probability are similar pixels of original image. The cross entropy can be assembled and calculated between probability distribution of the two new histograms. By analyzing the relationship between peak and valley of the maximum of entropy functional curve,the best multi-thresholds for segmentation image can be achieved. This method is simple and clear, and the experiment shows this method is effective.

Color image segmentation of multi-resolutin Markov random field in combination with multi-space characteristics

YANG Hua-yong YU Zheng-hong ZHENG Chen

2011, 31(12):  3378-3381. 

Asbtract ( )   PDF (638KB) ( )  

Related Articles | Metrics

This paper proposed a new Multi-Space Multi-Resolutin Markov Random Field Model (MS-MRMRF). Concerning the inadequate description of the color images in a single RGB space, the proposed model firstly transformed images from the RGB color space to the HSV color space and combined these two color spaces as a multi-space feature; then a new multi-resolution Markov model was designed to segment the image based on the multi-space feature, which estimated the parameters by fuzzy theory. The experiments of the color images demonstrate that the segmentation results of MS-MRMRF model have a higher segmentation accuracy compared with the segmentation results of multi-resolution MRF with a single RGB space.

Linking algorithm of discontinuity crack block based on autonomous edge growing

ZHU Ping-zhe LI Wei

2011, 31(12):  3382-3384. 

Asbtract ( )   PDF (495KB) ( )  

Related Articles | Metrics

In order to deal with the problem of false information and edge breakpoint about binary image of asphalt pavement crack image segmentation, a new method of discontinuity crack block linking was developed based on autonomous edge growing. This method removed false information according to the characteristics of circular noise and linearly cracks, and filled interstice by using method of region filling, thereby accomplished linking of discontinuity crack block based on autonomous edge growing. The experimental results show that the algorithm has excellent performance in edge linking of discontinuity crack block in different cases, and the noises can be removed at the same time, which is in favor of subsequent image processing such as image measurement and evaluating.

Coronary vessel diameter measurement based on MoM evaluation model

XIN Dong WANG Yan-nian PAN Jing-si

2011, 31(12):  3385-3387. 

Asbtract ( )   PDF (638KB) ( )  

Related Articles | Metrics

In the base of extracting vascular centerline using skeletonization algorithm, the tracking method of coronary vessel diameter measurement based on Measure of Match (MoM) evaluation model was proposed. The algorithm took account of the symmetry between the two edge lines of blood vessels and the centerline, and the optimized evaluation idea. By the quantitative measurement of the actual image and comparison with the actual diameter, it was found that using the proposed method can accurately measure blood diameter, and can effectively address the overlap of vascular branching and diameter measurement problems.

Face detection and location method based on a cooperative dual-camera system

SUN Zhuo-jin HU Shi-qiang

2011, 31(12):  3388-3391. 

Asbtract ( )   PDF (633KB) ( )  

Related Articles | Metrics

The major aim for modern video surveillance is to capture clear imagery of Region of Interest (ROI) in large-scale and scene. However, it is hard to achieve the goal by zooming when the ROI is far from the surveillance system. A station-motion camera system was designed to acquire the detailed and overall information of pedestrian at distance to obtain the facial feature. A stationary wide Field Of View (FOV) camera was used to monitor an environment for detecting pedestrians by improved Codebook background subtraction. Then a Pan-Tilt-Zoom (PTZ) camera was steered to track a target detected in the stationary camera, and zoomed in it speedily when pedestrian stopped moving. Afterwards, a face detection procedure used the images received from PTZ camera to obtain pedestrian face. Once the face was detected, PTZ camera put it in the center of the FOV and zoomed to acquire high-definition image. While the pedestrian continued moving, PTZ camera received the location of pedestrian from the station camera and tracked it continually. The experiments on real indoor and outdoor environments show that the proposed wide FOV camera pedestrian detection algorithm is robust to illumination variations, and the PTZ camera can track and zoom in the face of pedestrians. Besides, the speed of the method meets the real-time requirement.

Weighted improvement method based on local gray-level model of active shape model

HAN Yu-feng WANG Xiao-lin

2011, 31(12):  3392-3394. 

Asbtract ( )   PDF (592KB) ( )  

Related Articles | Metrics

In the searching of ASM algorithm for target point, only surrounding local gray-level information of fixed point is adopted. Then, two points is often confused, which have both similar gray-level and widely different texture details. Consequently, the accuracy of positioning is not ensured. The paper suggests that the real feature point probability of bilateral candidate points in the normal direction decreases in turn, so Gaussian distribution is brought in to represent the probability. Thus, better candidate points in the target image can be searched and the accuracy of positioning is improved.

Trademark retrieval by combining Fourier descriptors and SIFT features

WANG Zhen-hai

2011, 31(12):  3395-3398. 

Asbtract ( )   PDF (767KB) ( )  

Related Articles | Metrics

Traditional trademark image retrieval algorithm only using global feature easily make mistaken retrieval, and Scale Invariant Feature Transform (SIFT) features have limited descriptive ability for image contour and high algorithm complexity. According to the problem above, a new retrieval algorithm for trademark was proposed which combined the global feature and the local feature of images. The global feature reflects the overall information of the image that can help to build the candidate image database quickly, while the local feature can be matched with the candidate images more accurately. Firstly, extract Fourier Descriptor (FD) of the retrieved image and sort them according to similarity. And then, based on this result, the candidate images were matched accurately through extracting the SIFT features. The experimental results show that this method not only keeps high recall-precision of SIFT features and is superior to the method based on the single FDs feature, but also compared to the single SIFT features it effectively improves retrieval speed. This method can be well applied in the trademark image retrieval system.

Moving object detection based on local updated layered codebook

XU Xue-mei MO Qin NI Lan GUO Qiao-yun LI An

2011, 31(12):  3399-3402. 

Asbtract ( )   PDF (664KB) ( )  

Related Articles | Metrics

In background subtraction, it is challenging to detect foreground objects in the presence of complex background motions including waving trees, rippling water, illumination changes, etc. In order to solve this problem, a codebook-based object detection algorithm is proposed in the paper. Given that in actual scene the change of background reflects on brightness, color space is transformed from RGB space to YUV space for video sequences. Then the algorithm establishes a Box model which makes the codewords representation and training period more compact than the standard codebook. Besides, A local updated method, namely through frame difference to detect the region of variation, is incorporated into layered codebook to update the background real-timely, thus achieving more accurate foreground detection. Comparative results indicate that the algorithm can handle scenes containing moving backgrounds or illumination variations, and it achieves robust object detection for different types of video.

Invariant feature extraction of amount Chinese characters based on Ridgelet transform

YU Ying DONG Cai-lin

2011, 31(12):  3403-3406. 

Asbtract ( )   PDF (611KB) ( )  

Related Articles | Metrics

To meet the requirements of multi-directional choice, a new approach to the invariant feature extraction of handwritten amount Chinese characters was raised, with Ridgelet transform as its foundation. As far as this approach is concerned, first of all, the original images would be rotated to the Radon circular shift by means of Radon transform. On the basis of the characteristic that Fourier transform is row shift invariant, then, the one-dimensional Fourier transform would be adopted in Radon field to gain the conclusion that magnitude matrixes bear the rotation-invariance as a typical feature, which was pretty beneficial to the invariant feature extraction of rotation. When this was done, one-dimensional wavelet transform would be carried out in the direction of rows, thus achieving perfect choice of frequency, which made it possible to extract the features of sub-line in the appropriate frequencies. Finally, the average values, standard deviations and the energy values would form the feature vector which was extracted from the Ridgelet sub-bands. The approaches mentioned in the paper could satisfy the requirements from the form automatic processing on the recognition of handwritten amount Chinese characters.

Typical applications

Implementation and design of equalizer and carrier recovery loop for high order QAM signals over cable

MA Si-qiang CHEN Yong-en

2011, 31(12):  3407-3410. 

Asbtract ( )   PDF (793KB) ( )  

Related Articles | Metrics

In view of the characteristics of cable channel, a joint design of adaptive equalizer and carrier recovery loop for high order QAM signals was proposed, which was suitable for ITU-T J.83 standard. The equalizer initially operated in Constant Modulus Algorithm (CMA) mode to compensate the channel distortion. When the eye diagram was opened, the equalizer switched to Least Mean Square (LMS) mode to decrease the Mean Square Error (MSE). For high order QAM signals, the carrier recovery loop initially operated in Polarity Decision Algorithm (PDA) under fast and slow modes which were set in Loop Filter (LPF) to capture the frequency offset. When the frequency offset was captured, the loop switched to Decision Direct Algorithm (DDA) to decrease the phase jitter. The simulation studies show the good performances of this design. The whole design was synthesized under Altera Stratix Ⅱ EP2S130F1020C5 FPGA. Highest clock frequency after being routed reached as high as 90.47MHz.

Application of G(Galam) model in network public opinion evolution

CHEN Fu-ji LI Lin-bin

2011, 31(12):  3411-3413. 

Asbtract ( )   PDF (488KB) ( )  

Related Articles | Metrics

The evolution analysis of network public opinion becomes rather complex because of its interaction, diversity and derivability. At first, this paper analyzed the features of the source, content, dissemination and influence of network public opinion,and introduced G (Galam) model which was applied to the study of the evolution of network public opinion. Through experimental analysis, it is concluded that the final polarization direction of the evolution of network public opinion has certain regularity and controllability. Through the intervention in public communication between individuals and the influence on public in public preferences, the direction of the ultimate evolution of network public opinion can be guided.

Visual servo tracking method based on automatic identification system for vessels in controlled areas of Yangtze River

JIN Zhi LIANG Shan CAO Fang-ping

2011, 31(12):  3414-3417. 

Asbtract ( )   PDF (701KB) ( )  

Related Articles | Metrics

It is difficult to effectually track and monitor a vessel by video monitoring in narrow and winding controlled areas of Yangtze River. In this situation, directly using the common method for maritime video surveillance would result in tracking lag, alignment error, and even loss of target. A method of combining Automatic Identification System (AIS) and multiple Pan-Tilt-Zoom (PTZ) cameras was proposed to trace and monitor the vessel in controlled areas of Yangtze River. The latitude and longitude of the target vessel were utilized to initialize the alignment of PTZ cameras. Meanwhile, vessel’s speed and heading were applied for dynamic prediction tracking to smoothen image and eliminate tracking lag, while image recognition was employed to correct error for ensuring that target vessel was located in the optimum surveillance area.The simulation results indicate that this algorithm can not only track target vessel continuously and dynamically, but also realize the real-time target tracking with high precision.

Message generation and store model based on HL7V2.x protocol

FAN Xiao HUANG Qing-song

2011, 31(12):  3418-3421. 

Asbtract ( )   PDF (561KB) ( )  

Related Articles | Metrics

Data can not be communicated so well according to the unified data standards among the health information systems in our country that information sharing is impeded. On the basis of the HL7 V2.x (health level seven Version2.x) protocol of health information communication standard and the theory of HL7V2.x message parsing, the method in which data in the database fields is extracted to generate HL7V2.x messages and parsed message information is stored in the specific database is introduced in detail. Then an optimized model of the message store and the message generation is brought forward. In this model, mapping files are designed to save much time in redundant manual configurations and the hash table is used as a data structure during the process of message generation to make it more efficient. Simulation experiment results show the feasibility of the model.

Design of new structural health monitoring system based on first in first out

SHENG Wen-juan GUO Ai-huang

2011, 31(12):  3422-3424. 

Asbtract ( )   PDF (509KB) ( )  

Related Articles | Metrics

High-speed and real-time data acquisition and accurate measurement are very important to structural health monitoring. Traditional serial processing based structural health monitoring system has to stop data acquisition while it is analyzing sensing data, so the data acquisition process is discontinuous, and real-time data acquisition rate is limited. This paper designed a new structural health monitoring system with Fiber Bragg Grating (FBG) sensors, and the real-time data acquisition rate was improved greatly by introducing FIFO into serial processing mode. The experimental results demonstrate that the introduction of FIFO technology is effective to increase real-time data acquisition rate, and the maximum improvement is 100%. The impact of data acquisition on measurement accuracy has also been minimized at the same time.

Modelling and simulation analysis on storage-transportation system of aviation ammunition in aircraft carrier

YUE Kui-zhi HAN Wei CHEN Xiao-wei SHI Jian-guo

2011, 31(12):  3425-3428. 

Asbtract ( )   PDF (838KB) ( )  

Related Articles | Metrics

The forecasting model about aviation ammunition storage-transportation system with automatic regulatory system in aircraft carrier to replenish the required aviation ammunition timely was established. This paper studied the storage and transportation system about aviation ammunition, built the causal loop diagrams and stock and flow diagrams about every element impacting the storage-transportation efficiency of aviation ammunition with the method of system dynamics and simulated by the system dynamics software Vensim PLE 5.9. The simulation results show that this model can predict the storage and transportation trend about aviation ammunition under the condition of perturbation, which correspond with the data and conclusion of exercises with aircraft ammunition storage system.

MRI equipment remote monitor and control system based on multilayer structure of C/S

CHEN Jian-feng XU Hao-jie DAI Song-shi ZHU Shan-an

2011, 31(12):  3429-3433. 

Asbtract ( )   PDF (850KB) ( )  

Related Articles | Metrics

To solve the problems of decentralized management and lack of remote technical assistance, the paper proposed a remote monitor and control system for Magnetic Resonance Imaging (MRI) equipments. Based on the multilayer structure of C/S and remote monitoring technique, the system consisted of four parts: client, query server, device server and device. These parts adopted the frameworks of .NET, Twisted and MFC, while Twisted was an open event-driven framework for the server. To protect the secret data, the survey attached great importance to security architecture, such as the authorization code and the encryption technique. The system realized the functions of remote data transfer and control based on the 3G communication technology, and the virtual channel between the MRI devices and remote clients help the enterprise manage the devices remotely. After the systematic testing and the trial operation, the system is now successfully applied to the actual working environment, and it has good performance.

Method for drawing double-track high-speed maglev train diagram based on knitting algorithm

ZHANG Qi-liang CHEN Yong-sheng DU Lei

2011, 31(12):  3434-3437. 

Asbtract ( )   PDF (650KB) ( )  

Related Articles | Metrics

Based on the characteristics of high-speed maglev train line structure and operation control system, this paper set up a model for the high-speed maglev train diagram of double-track lines, and put forward the knitting algorithm to resolve the model. The algorithm drew the up and down maglev train running lines in chronological order of trains’ departure time from stations, which tended to do some knitting. When meeting the conflict, the algorithm resolved it by changing the station tracks or increasing the departure time intervals, at last it gained global optimization maglev train diagram step by step. A numerical example shows that the method can draw the maglev train diagram quickly and effectively.

Wearable ECG-signal quality assessment based on fuzzy comprehensive judgment

YI Xiao-lin WU Yi-zhi

2011, 31(12):  3438-3440. 

Asbtract ( )   PDF (576KB) ( )  

Related Articles | Metrics

With a comprehensive analysis on R-wave detection matching degree, power spectral density ratio and kurtosis,three indexes for electrocardiogram (ECG) signal quality, this paper established a quality assessment model for a wearable ECG-signal based on fuzzy comprehensive judgment, obtained the quality indexes and quality degree for ECG-signal. Then through a comparison and discussion for this algorithm, the results show that the using of fuzzy comprehensive assessment method can reduce the erroneous assessment in the condition of disturbance to some extent.

Removal of impulsive noise based on Kalman filtering for speech enhancement

HE Zhi-yong ZHU Zhong-kui

2011, 31(12):  3441-3445. 

Asbtract ( )   PDF (764KB) ( )  

Related Articles | Metrics

Speech enhancement aims at extracting clean speech from noisy speech. Traditional speech enhancement algorithms proposed for continuous noise can not work well when clean speech is polluted by impulsive noise. The feature of the distribution of impulsive noise in time domain has to be concerned for speech enhancement. This paper provided a new speech enhancement method for the removal of noise when clean speech is polluted by stationary impulsive noise. By analyzing the samples of impulsive noise and noisy speech, the method found the frequency band in which the energy of impulsive noise was most evident compared with the energy of noisy speech. Furthermore, filter banks were used in recognizing whether the speech frame was polluted. The method based on Kalman filtering removed impulsive noise from the polluted signal frame. Compared with the traditional algorithms based on Kalman filtering, the method also improved the process of the parameters estimation of Auto Regressive (AR) model. In some speech enhancement tests, speech was polluted by white impulsive noise or colored impulsive noise, the results show that the method has achieved an improved Signal-to-Noise Ratio (SNR) and removes impulsive noise even when the SNR of noisy speech is low.

Classification of cotton foreign fibers based on multi-class support vector machine

YANG Wen-zhu LU Su-kui WANG Si-le

2011, 31(12):  3446-3448. 

Asbtract ( )   PDF (579KB) ( )  

Related Articles | Metrics

This paper proposed a new classification method based on Multi-class Support Vector Machine (MSVM) which aimed at solving the problems in online classification of cotton foreign fibers. Firstly the features of color, shape and texture of the foreign fiber objects were extracted to create the feature vectors. Secondly three kinds of multi-class support vector machines were constructed for foreign fiber classification. These three MSVMs were tested with the obtained feature vectors using leave-one-out cross validation. The experimental results show that the one-against-one directed acyclic graph MSVM is the fastest one and is fitter for online classification of foreign fibers.

Design of LED dot display screen based on GPRS SMS control

CAI Zhi-shan

2011, 31(12):  3449-3452. 

Asbtract ( )   PDF (617KB) ( )  

Related Articles | Metrics

To meet the needs of small and medium businesses, a remote control project for LED text display screen with a low cost and easy content updates was designed in this paper. A MCU was used as processing core and GPRS/GSM communication standards were adopted in this system. The control commands and display data emitted from a phone were received by GPRS module mounted on the screen. The received data were then processed to control scan display of the LED screen. Remote update display contents on the LED screen were realized finally. After a period of practical use, the system operation is stable and reliable, and achieves design requirements.