Author Login Editor-in-Chief Peer Review Editor Work Office Work

05 May 2009, Volume 35 Issue 9
    

  • Select all
    |
    Degree Paper
  • SUN Quan-bao; ZHANG Min-xuan; XIAO Li-quan
    Computer Engineering. 2009, 35(9): 1-3. https://doi.org/10.3969/j.issn.1000-3428.2009.09.001
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Supporting multicast at hardware level is a trend of high performance interconnection networks. To minimize the router transmitting latency of multicast packet, this paper presents the Maxed Served First Served(MSFS) multicast schedule algorithm to assign priority to a multicast packet according to the number of destination ports which have received the packet and the waiting time of the packet at the head of buffering queue. The implementation of MSFS is simple. When unicast and multicast coexist, MSFS can be integrated with FCFS unicast schedule algorithm smoothly. The simulation results show that MSFS can lead to high and stable communication performance.
  • WANG Wei-jiang; LI La-yuan; ZHENG Feng
    Computer Engineering. 2009, 35(9): 4-6,10. https://doi.org/10.3969/j.issn.1000-3428.2009.09.002
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at the inaccuracy in the module of MFW for OMNeT++, the function of PHY/MAC in this module is modified and mended, which implements the rate adaptation MAC protocol based on RBAB in IEEE 802.11b and a simulation model framework is constructed for cross layer network protocol stack with the modified module. An instance about cross layer design which joints rate adaptation in MAC layer and routing algorithm in network layer to improve performance of mobile Ad Hoc network is studied based on this simulation model framework. The simulation results show that cross layer design in the application of Ad Hoc network protocol stack improves the performance of Ad Hoc network significantly in the mobile wireless environments.
  • ZHAO Xiong-wei; GUO Jin-huai; YU Hong-yi; HU Han-ying
    Computer Engineering. 2009, 35(9): 7-10. https://doi.org/10.3969/j.issn.1000-3428.2009.09.003
    Abstract ( )   Knowledge map   Save
    The Cooperative diversity and Network Coding(NC) have shown their advantages in wireless communication. In order to combine the superiority of these two techniques, the concept of cooperative NC is proposed. This paper discusses one type of cooperative network coding model, and analyzes the performance of two difference decoding methods. It compares the Bit Error Rate(BER) bounds of two different receiving methods at large Signal Noise Ratio(SNR) regime. The result shows that the diversity order of this model is two, and the receiver performance based on decoding method 1 is better than which based on the method 2. If the NC parameters are linear independence, different parameters affect only the coding gain not the diversity order.
  • LIU Liang; LI Long-shu
    Computer Engineering. 2009, 35(9): 11-13,1. https://doi.org/10.3969/j.issn.1000-3428.2009.09.004
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Many multi-Agent Q-learning problems can not be solved because the number of joint actions is exponential in the number of Agents, rendering this approach infeasible for most problems. This paper investigates a regional cooperative of the Q-function by only considering the joint actions in those states in which coordination is actually required. In all other states single-Agent Q-learning is applied. This paper offers a compact state-action value representation, without compromising much in terms of solution quality. It performs experiments in RoboCup-simulation 2D which is the ideal testing platform of multi-agent systems and compared the algorithm to other multi-Agent reinforcement learning algorithms with promising results.
  • LI Yu-dong; REN Jian-yue; JIN Long-xu
    Computer Engineering. 2009, 35(9): 14-16. https://doi.org/10.3969/j.issn.1000-3428.2009.09.005
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at low power consumption design of embedded system, a software power management model is put forward, which based on object-oriented principle. On the foundation of operating system, the related APIs are packed and expended. In the mean time, four classes are abstracted which are Operating System Power Management class(OSPM), CPU Power Management(CPUPM) class, Device Driver Power Management(DDPM) class and Application Power Management(APM) class. Within operating system level, device driver level, application level, and the power management interface are formed which make the software of power management easy to design and defend for embedded system.
  • SUN Da; HUANG Jian-hua; TANG Xiang-long
    Computer Engineering. 2009, 35(9): 17-18,2. https://doi.org/10.3969/j.issn.1000-3428.2009.09.006
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    A new method is proposed to measure the track of mobile object in large ground field, which uses the rotation camera to extend the range and precision of monocular camera. The method uses the scene compositing technique to align every image to get the homograph matrix between the ground filed and every frame. By recognition and tracking, the object can be located in every frame, and the coordinates are mapped to the real field. Compared with static camera method, the method needs less equipments and is flexible and easy for operation.
  • DANG Chen; WANG Jia-zhen; LIU Ai-zhen; ZHAO Xin-qing
    Computer Engineering. 2009, 35(9): 19-21. https://doi.org/10.3969/j.issn.1000-3428.2009.09.007
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    By modeling Mobile Agent(MA) server system model, this paper presents a MA intelligent migration algorithm founded on ant colony algorithm. It uses Mobile Agents to detect the global system status, which can minimize costs by detecting software. When Mobile Agents arrive at servers’ nodes, they can feel the pheromone by others laid. According to the pheromone, they choose a shorter route to move intelligently. Experimental results show that algorithm can adapt to environmental changes and has fault tolerant. It introduces the self-adjust pheromone to add intensity coefficient, so that MA can move more efficiently.
  • LIU Chang; ZHOU Ji-liu; HE Kun; Duan Yu-mei
    Computer Engineering. 2009, 35(9): 22-24. https://doi.org/10.3969/j.issn.1000-3428.2009.09.008
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The variety of facial pose and expression will affect the result of facial recognition. The traditional methods analyses facial pose and expression from every pixel of image on the contrary. This paper analyses the pose and expression from geometric relationship among image data. It uses Locally Linear Embedding(LLE) which computes low dimensional, neighborhood preserving embedding of high-dimensional data. The algorithm finds the nonlinear structure of data effectively, invariable to translation, revolution and so on. Experiment shows that the algorithm has capability to reflect the slight variety of facial pose and expression, and indicates that the low-dimensional distribution of various pose and expression is identical to different persons and the original image can be reconstructed exactly from neighboring images.
  • Software Technology and Database
  • LI Yue-e; XIA Shi-xiong; ZHOU Yong
    Computer Engineering. 2009, 35(9): 25-27. https://doi.org/10.3969/j.issn.1000-3428.2009.09.009
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at the problems that it ignores the different effect which the median and wide of interval play on the analysis of interval number, this paper presents a new measure of distance based on the median and wide of interval with different weight. On basis of this, a revised clustering algorithm is proposed. The experiments of the simulative and practical datasets are made by this algorithm and IADFCM. Experimental results indicate this algorithm is effective.
  • CHEN Yi-fei; YE Xiao-ling; ZHANG Ying-chao
    Computer Engineering. 2009, 35(9): 28-30. https://doi.org/10.3969/j.issn.1000-3428.2009.09.010
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The concept of weight is introduced in fuzzy queries based on theory of fuzzy set, which shows the relative importance that users pay to different attributes in query clauses. The records that satisfy queries are output according to the decrease of matching degrees, so users can select what they want more conveniently. Weights and matching degrees are linguistic variables, whose values are linguistic terms, and the queries become more flexible. The alpha-cut of fuzzy set is used to translate the linguistic fuzzy querying conditions into crisp SQL clauses. It is possible to make use of the mechanism of RDBMS to filter the records, which avoids scanning the whole table and assures the efficiency.
  • LIANG Gen; QIN Yong; GUO Xiao-xue; LIANG Huo-min
    Computer Engineering. 2009, 35(9): 31-33,3. https://doi.org/10.3969/j.issn.1000-3428.2009.09.011
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at the problem of poor control ability of distributed system with fixed nodes, this paper gives a task scheduling model of distributed system. The problem of task scheduling in single node is discussed. In order to depict the capability of load-tolerance clearly, the processing intensity concept is drawn. The method of task scheduling among dynamic multi processing nodes is deduced to optimize the characteristic of responsibility time in task scheduling. Simulation experiments show that this algorithm has a better control ability, and it can reduce load of processor, improve the performance of the task-processed delay and use the resource of system more legitimately.
  • Wushou Sliamu; HOU Yong; ZHOU Yan-hui
    Computer Engineering. 2009, 35(9): 34-36. https://doi.org/10.3969/j.issn.1000-3428.2009.09.012
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The problem of unbalanced of metatask scheduling in the performance predicted and scheduling system, Grid Harvest Service(GHS), are researched. In order to solve the problem, a Heuristic Min-Min and Max-Min algorithm(H-MM) is proposed and implemented into GHS to schedule tasks. Experimental results show that the algorithm overweighs traditional algorithms a lot in makespan and scalability parameters.
  • ZHENG Jun; WANG Wei; YANG Wu; YANG Yong-tian
    Computer Engineering. 2009, 35(9): 37-39,4. https://doi.org/10.3969/j.issn.1000-3428.2009.09.013
    Abstract ( )   Knowledge map   Save
    The evaluation method of text clustering uses the parameter estimation technique in statistics. It takes parameter estimation to estimate the numerical characteristics of the distances’ distribution according to the data of distances between clusters. According to the results of the estimation, the logical range of the distances between clusters is worked out. And the clusters between which the distances are not in the range should be rectified. But the final result must be validated by cluster validity test function. The method improves the text clustering algorithm’s precision, and also provides a feasible method to choose and compare between different clustering algorithms. The final experiment results indicate that the evaluation method is feasible and effective.
  • HE Xiao-yuan; MIN Hua-qing
    Computer Engineering. 2009, 35(9): 40-42. https://doi.org/10.3969/j.issn.1000-3428.2009.09.014
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Considering that R-tree is suitable for the dynamic index, its spatial overlap between nodes is great, and Hilbert R-tree cannot reduce the coverage and overlap effectively, which influences directly R-tree querying efficiency. In order to meet the demands of many GIS querying applications, the Hilbert R-tree index algorithm based on the nodes clustering is proposed. The algorithm resolves preferably the clustering storage for the adjacent data, decreasing the leaf nodes MBR area and the spatial overlap between interior nodes. Experiments conducted and performances are analyzed for the algorithm. The results show that the algorithm has high efficiency in querying.
  • ZHANG Zhong-wu; WU Xin-cai
    Computer Engineering. 2009, 35(9): 43-45,4. https://doi.org/10.3969/j.issn.1000-3428.2009.09.015
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Being a basic structure of computational geometry, convex hull is important to data analysis of GIS. Based on the analysis of traditional convex hull algorithm, a new convex hull algorithm is presented, i.e. pyramid algorithm. It adopts three fast algorithms simultaneously to improve execution efficiency. Comparison of much experiment data shows that the algorithm is very efficient for calculating convex hull of planar massive scattered point set, and for the point set of 107 level, its execution time on a 2.00 GHz personal computer is only three to four seconds.
  • XIAO Jin-ge; ZHAO Rong-cai; SHAN Zheng; ZHANG Zheng
    Computer Engineering. 2009, 35(9): 46-48. https://doi.org/10.3969/j.issn.1000-3428.2009.09.016
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The traditional formalization description of rule in packet classification is improved. On basis of research on rule conversion method, a novel non-match rule conversion algorithm based on sets is proposed. Its performance is compared with other relevant algorithms, and the time and space complexity are also analyzed and simulated. Experimental results show the amount of rules created by this algorithm is far less than others.
  • CHEN Dong-ping; LIU Xiao-jie; LI Tao; HU Xiao-qin; YANG Xiao-long; KANG Shi-liang; HUANG Cheng-ji
    Computer Engineering. 2009, 35(9): 49-51,5. https://doi.org/10.3969/j.issn.1000-3428.2009.09.017
    Abstract ( )   Knowledge map   Save
    Due to the backup data storage structure of remote disaster tolerant system depends on the data source, the resource in the backup center is extremely wasted. According to this problem, this paper presents a remote backup data storage method. With the backup data been encapsulated and storage space allocated dynamically, the method supports multi-tasks’ backup data be stored in the shared storage space and the storage structure of the backup data in the backup center be independent of the data source. The experiment proves that the method not only can improve the efficiency of system resource, but also can provide better storage performance.
  • TANG De-quan; ZHU Lin-li
    Computer Engineering. 2009, 35(9): 52-54. https://doi.org/10.3969/j.issn.1000-3428.2009.09.018
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Graph can express richer semantic meaning, but enhance the complexity of data structure and increase the difficulty of interested sub-graph mining. The knowledge of graph and data mining technology is applied comprehensively to accomplish canonical coding of graph. Candidate subgraph is generated by join and extension operation. The value of support and frequency of candidate subgraph is counted by maintaining an embedded set. Algorithm FSubgraphM is proposed to mine frequent induced subgraph from graph database.
  • ZHANG Hao; WANG Kui-sheng; FANG Ming
    Computer Engineering. 2009, 35(9): 55-56,5. https://doi.org/10.3969/j.issn.1000-3428.2009.09.019
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In the management information system development process, the traditional tree generation solution to achieve the generation of tree can bring the serious problem of efficiency during the implementation of program. This paper puts forward a Tree Generation Solution Based on Genericity(TGSBG), including its design and implementation, and describes a tree generation algorithm about TGSBG with a formal method. The experiment shows that TGSBG and its algorithm can improve the program efficiency at runtime and data access speed.
  • CAI Chun-li; WANG Hui-ling; SUN Yan-ming
    Computer Engineering. 2009, 35(9): 57-59. https://doi.org/10.3969/j.issn.1000-3428.2009.09.020
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    On basis of analyzing the advantages and weaknesses of the current clustering algorithm of data streams, this paper introduces a new density-based clustering algorithm in evolving data streams——SDStream, which can analyze and deal with large-scale evolving data stream. Its performance is tested by using both real datasets and synthetic datasets. Experimental results show this algorithm has better perpformance of applicability, effectiveness and extension and achieves a higher quality of clustering.
  • CAI Zhao-quan; LU Qing-wu; ZHENG Zong-hui; LUO Wei
    Computer Engineering. 2009, 35(9): 60-62,6. https://doi.org/10.3969/j.issn.1000-3428.2009.09.021
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at the contradiction between fast changing needs of applications and slow response of software development, according to SOA and metadata, by encapsulating business logic in software component, this paper implementes a new rapid development platform using workflow technology to control the process. Test results show that the new platform can speed up software development and enhance software’s quality, and it can be applied in a wide range.
  • WU Jian-hua; SHEN Jun-yi; WANG Yuan-yuan
    Computer Engineering. 2009, 35(9): 63-65. https://doi.org/10.3969/j.issn.1000-3428.2009.09.022
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Classification Based on Association(CBA) algorithm is one of the main methods in data mining. However, this algorithm only uses confidence parameter to process classification problem which may impact the classification accuracy. In this paper, a new improved method of CBA is presented. On the basis of CBA method, shorter rules are selected firstly for classification. Experimental results show this algorithm has higher classification accuracy and fewer numbers of classification rules than traditional ones.
  • HE Zhen-xiang; DONG Yi-sheng
    Computer Engineering. 2009, 35(9): 66-68,7. https://doi.org/10.3969/j.issn.1000-3428.2009.09.023
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    It is necessary to consider the user’s suitability in the process of different physical implementation in the same functional service when constructing the SOA. This paper proposes a method to definite the attributive set of service Quality of Service(QoS) according to the user’s request. In this method, the service QoS is described by the extended WSDL and the QoS of service and user is quantified. It constructs the QoS model based on the user’s request and the relevant algorithm to finish the choice of the physical realization of service with the best user’s suitability.
  • ZHAO Li-na; JIA Yu-dong; OU Pan
    Computer Engineering. 2009, 35(9): 69-71. https://doi.org/10.3969/j.issn.1000-3428.2009.09.024
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Embeded Linux device drivers becomes more and more complicated in the movement of widespread usages of embedded applications, the configuration and compiling command investigation turns into its outline and difficulty. This paper simply explains the elements and flow of device drivers programming, emphasizes on the configuration and compiling command Kbuild about deep directory drivers, involving kernel configuration language and kernel Makefile file, investigates the Config.in and Makefile under each directories. It joins the source code in the Linux kernel in order to increase the kernel configuration options and gain corresponding compilation result. Loading modules orderly according to the modules dependence, modules run well.
  • GAO Xiao-lei; MIAO Huai-kou
    Computer Engineering. 2009, 35(9): 72-73,7. https://doi.org/10.3969/j.issn.1000-3428.2009.09.025
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Proof and test are two ways to check specification, and they are complementary. Aiming at the problem that specification is difficult to be proofed, this paper proposes the theory of completeness test of states space. The concepts of constructed function and constrained states space are used. The test approach used to detect the existing of initial state in Z specifications language is discussed, and the feasibility of this approach is proved by application example.
  • LIU Yang; HU Shi-cheng; CHU Dian-hui; XU Xiao-fei
    Computer Engineering. 2009, 35(9): 74-76. https://doi.org/10.3969/j.issn.1000-3428.2009.09.026
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In order to decide those who meet the demand of an enterprise among multiple suppliers and how many should be purchased Just-In-Time(JIT) form them, a two-phase multiple supplier selection and purchasing model is proposed. The Analytic Hierarchy Process(AHP) is used to evaluate each supplier with respect to the qualitative criteria. The cost optimization model for supplier selection and purchasing, which is based on the quantitative criteria, is employed to implement further selection from those selected in the first phase for the sake of deciding the final suppliers and their supply quantities. Practical application results show that the model can help enterprise not only select out the best qualified suppliers, but also reduce the purchasing cost as well as the whole product cost greatly.
  • HE Yan-xiang; HU Wen-sheng; LI Fei
    Computer Engineering. 2009, 35(9): 77-78,8. https://doi.org/10.3969/j.issn.1000-3428.2009.09.027
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Deficiency and limitations of wireless network and mobile terminals, and the particularity of GIS data blocks the development in mobile GIS. Aiming at this problem, this paper presents a progressive query method for a mobile GIS service and the corresponding data structure. Experimental results prove that this method can cut down the processing time and increase the data transfer efficiency.
  • XIE Fu-cheng; WANG Bei-zhan; SHI Liang; JIANG Qing-shan
    Computer Engineering. 2009, 35(9): 79-81. https://doi.org/10.3969/j.issn.1000-3428.2009.09.028
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Metadata plays an important role in bank data warehouse. This paper discusses the categories and functions of metadata, and analyzes the management function of metadata. It presents a metadata manage system based on bank data warehouse, analyzes and illustrates its structure. Application results show that this system can increase the ability of data analysis and management, and improve the flexibility and expansibility of the decision system such as bank data warehouse.
  • Networks and Communications
  • HUANG Jing-lian
    Computer Engineering. 2009, 35(9): 82-85. https://doi.org/10.3969/j.issn.1000-3428.2009.09.029
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    To overcome the defect of IEEE 802.11e Hybrid Coordination Function(HCF) lack of how to implement admission control and access time, this paper proposes an adaptive admission control scheme named AAC to support real-time traffic. By considering burst and load factors, it dynamically allocates variable Transmission Opportunity(TXOP) duration with guaranteeing minimum delay and packet loss rate of traffic to improve throughput. Simulation results and comparison with IEEE 802.11e reference admission control scheme prove that the scheme decreases delay and packet loss rate of real-time traffic, and improves throughput of the system.
  • TANG Chao-wei; SHAO Yan-qing; LIANG Teng; MA Wen-xing; LIU Peng-jun
    Computer Engineering. 2009, 35(9): 86-88. https://doi.org/10.3969/j.issn.1000-3428.2009.09.030
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The sleep window of Mobile Station(MS) can affect energy saving performance and Average Response Time(ART) of receiving data frames. In order to get better energy saving effect and shorter average response time, this paper proposes a novel Superposition Growth Algorithm(SGA). The algorithm defines that the length of the kth sleep window is the sum of the length of the (k-1)th and the (k-2)th sleep window, which slows down the growth rate of the sleep window in every sleep period. Simulation results show that SGA is better than Exponential Growth Algorithm(EGA) prescribed by IEEE802.16e on Average Energy Consumption(AEC) and ART.
  • YIN Yi; WU Wei-dong; XING Su-zhen
    Computer Engineering. 2009, 35(9): 89-91,9. https://doi.org/10.3969/j.issn.1000-3428.2009.09.031
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    With complex network application, the effective transmission of packets is able to improve network congestion and increase network capacity. This paper improves the transmission of the probe with the packet, and at the same time transfers the probing packet and the data packet. The algorithm adjusts the transmission rate for the number of the sending probes. According to the return value of the probe, the send information of the packets can be ensured. As the measurement of probing packet matches the sending data packet, the transmission rate and return value of the packets can be observed favorably, and integration of data can understand the network operation.
  • LI You; WU Jie; LIU Bi-sheng; ZHONG Yi-ping
    Computer Engineering. 2009, 35(9): 92-95. https://doi.org/10.3969/j.issn.1000-3428.2009.09.032
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper analyzes the Peercast live stream media system, concludes that the system carries some shortcomings during its practical application to network and provides improvements. It redesigns downloading flow, and makes it into multithread downloading. It designs a module for managing downloading peers. It redesigns the buffers, and maintains the buffer in many-to-one environment. It introduces the improvements on network delay after the redesign of downloading flow and analyzes the functions of the redesigned system.
  • YUE Cheng-jun; YIN Feng-jie
    Computer Engineering. 2009, 35(9): 96-97,1. https://doi.org/10.3969/j.issn.1000-3428.2009.09.033
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Taking account of unfairness of the bandwidth, which due to the unfriendly TCP don’t obey to the TCP congestion control protocol, this paper presents a congestion control algorithm ensuring TCP-friendly flow fairness. A new robust discreted sliding mode controller is designed based on the max bound of the non-TCP friendly flow. It analyzes the characteristic of the non-TCP friendly flow, and the max translation value of an TCP-unfairness is estimated. It proposes controller regards the influence of unknown disturbances of non-TCP friendly flow and uncertain parameters as an equivalent disturbance, and estimates the value of the disturbance on line by the mechanism of router time delay, employing the value in designing the control law in order to cancel the slowly varying uncertainties. Simulation results show that the algorithm is highly robust against the disturbance under various networks conditions and outperforms significantly.
  • YING Yu-mei; LIU Wei; QIN He; DONG Meng
    Computer Engineering. 2009, 35(9): 98-100. https://doi.org/10.3969/j.issn.1000-3428.2009.09.034
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In order to balance the fairness and throughput of channel resources in wireless Ad hoc network, this paper proposes a distributed fair scheduling algorithm for multi-hop wireless Ad hoc network. The contention relationship of sub-flows are denoted by link contention graph, and the maximal independent sets are formed with coloring algorithm. The algorithm depends on local flow information obtained by information exchange between neighbor nodes. Simulation experimental result proves that the algorithm can efficiently maximize the throughput while maintaining basic fairness among flows.
  • SHU Yong-an; LUO Bin; SHI Bin-ning
    Computer Engineering. 2009, 35(9): 101-103,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.035
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    To support real time applications with Quality of Service(QoS) requirements in Wireless Mesh Networks(WMN), this paper proposes a TDMA-based QoS routing strategy named TD-MQR. This strategy stratifies WMN and proposes a new link metric. It routes and schedules the network traffic based on the link capacity and interference among wireless channels. Simulation results show that the strategy can provide QoS guarantees for real time applications in WMN.
  • LUO Jing; PENG Hai-ying; TANG Hong
    Computer Engineering. 2009, 35(9): 104-106. https://doi.org/10.3969/j.issn.1000-3428.2009.09.036
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper tests the performance of Transmission Control Protocol(TCP) Veno by using NS2 in MANET environment. Simulation results show that the performance of TCP Veno is superior to that of TCP Reno in MANET environment with background traffic, random packet loss and congestion. The larger background traffic and random packet loss are, and the shorter time congestion takes, the superiority of TCP Veno is more obvious. Compatibility of these protocols is dissatisfactory, leading to rise of retransmission in data package.
  • WANG Jian-ming
    Computer Engineering. 2009, 35(9): 107-109,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.037
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper aims at a mobile base station data collection mode, the best location of the buffer zone of mobile base station is studied. The conclusions include that when nodes radius of the transmitting r=R, the total energy consumption is minimize when the centre of the data buffer is located on 2/3R. The network longest life is expectancy when the centre of the data buffer is located on 1/2R. When the situation is r<
  • SU Jian; GUO Wei; LIU Qiang
    Computer Engineering. 2009, 35(9): 110-113. https://doi.org/10.3969/j.issn.1000-3428.2009.09.038
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In mobile Ad Hoc network, the rapidly changing node’s operating contexts leads to situations where a node currently providing a certain service becomes unsuitable for hosting that service any longer. Based on migratory service model, this paper presents a service migration mechanism which uses dynamic context-awareness, migration destination selection and mobile agent so as to keep providing service continuity. A service migration platform based on Aglets is implemented in mobile Ad Hoc network. Experiment verifies the feasibility of the platform.
  • JIANG Yun-xia; XU Zhen-yang; FU Qi; XU Jian-bo
    Computer Engineering. 2009, 35(9): 114-115,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.039
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    As the present routing protocols for WSNs is not fit for the requirement of enery consumption and delay for multi-actors in WSANs applications, the function of J-Sim for WSANs is used to design and implement the routing protocol BHOER for single-actor-selection model in WSANs. Result of simulation and analysis of performance made for BHOER are given wnich show that BHOER can fit for the routing requirement in WSANs.
  • ZHOU Xin-lian; XU Jian-bo
    Computer Engineering. 2009, 35(9): 116-118. https://doi.org/10.3969/j.issn.1000-3428.2009.09.040
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper analyzes and compares several typical existing data gathering protocols, and according to the actual application needs, designs a new data gathering protocol of Wireless Sensor Network(WSN)——Differentiated Service and Data Aggregation(DSDA). By constructing an agreement constitutes effective cluster-tree network topology, using differentiated service for the network data flow, and using network data aggregation technology for the data transmission process, DSDA improves the existing data gathering protocols. Simulation results with Matlab show that DSDA can reduce the overall energy dissipated in the network and prolong the network lifetime.
  • Security Technology
  • HE Jun; LI Li-juan; LI Xi-mei
    Computer Engineering. 2009, 35(9): 119-120. https://doi.org/10.3969/j.issn.1000-3428.2009.09.041
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Based on the intractability of the discrete logarithm, this paper proposes a verifiable multi-secret sharing scheme, and analyzes its security. In this scheme, several secrets can be shared during one secret sharing process simultaneously. Each participant chooses the secret share by himself, and the dealer is impossible to be a cheater. It need not to design special verification algorithm. This scheme is valuable in the environments where the security channels are not available.
  • ZHANG Guo-jun; LIN Nan-hui
    Computer Engineering. 2009, 35(9): 121-123. https://doi.org/10.3969/j.issn.1000-3428.2009.09.042
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The multi-pattern matching algorithm that based on Deterministic Finite Automata(DFA) needs a lot of memory. In order to reduce its memory requirement, the DFA is needed to optimize. This paper proposes a dynamic default transition algorithm to replace the failto transitions, eliminates most failto transitions of the DFA and achieves the memory optimization purpose. The experiment result shows the proposed algorithm can reduce the memory requirement of DFA effectively.
  • ZENG Zhi-gao; YI Sheng-qiu
    Computer Engineering. 2009, 35(9): 124-126. https://doi.org/10.3969/j.issn.1000-3428.2009.09.043
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In order to eliminate the potential safety problems of fingerprint identification and the security loopholes of dynamic password authentication, an enhanced two-factor identity authentication scheme based on ECC is designed. The random number generator, the encipherment scheme of the dynamic password and the fingerprint sequence are designed. And the performance and security of the authentication system are analysed.
  • HOU Ya-yi; QIAN Huan-yan; WANG Xiao-nan
    Computer Engineering. 2009, 35(9): 127-129. https://doi.org/10.3969/j.issn.1000-3428.2009.09.044
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Routing optimization provides the MIPv6 opportunity to improve the network performance. This paper proposes a routing optimization mechanism which applies the ID signature to make the identity of mobile nodes verified by the correspond nodes communicating. New protocol eliminates the certification authority dependence, and secures mobile nodes and correspond nodes from the attacks.
  • CHEN Hu; SONG Ru-shun
    Computer Engineering. 2009, 35(9): 130-132. https://doi.org/10.3969/j.issn.1000-3428.2009.09.045
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper propose a secure and efficient certificateless group signature scheme. It not only enjoys all the security requirements of a group signature, but also is a dynamic group signature scheme that allows users to join or leave the group freely without updating the group public key and other group members’ private signing key. The length of the signature is independent of the numbers of the group members. The security of the scheme is based on the fact that Computational Differ-Hellman Problem and inverse computational Differ-Hellman problem are hard.
  • XUE Yong-ling; HUANG Hao; ZHANG Bo
    Computer Engineering. 2009, 35(9): 133-135. https://doi.org/10.3969/j.issn.1000-3428.2009.09.046
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Current software attacks often build on exploits that subvert machine-code execution. This paper proposes a new signature monitoring technique to enhance the control-flow integrity of program. It uses the execution of function as the basic item of the control-flow of the program. To get more exact intent of program, it scans the source code, and gets the information of function call sequence. According to the information, the model of program’s intent can be built. The model is used to monitor the program in runtime. Experimental results show the monitoring system makes the program more secure to reject the control-flow attacks.
  • HU Jian-yong; SU Jin-hai
    Computer Engineering. 2009, 35(9): 136-138. https://doi.org/10.3969/j.issn.1000-3428.2009.09.047
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper presents a scheme for real time test of randomness according to the actual requirement, and expounds implement manner, organize manner and test method which are used in the project. This project is implemented with hardware and can be modularized, so it is transplantable and has upper speed of operation. It can be widely used to detect the quality of the random number generator which is used in various information safety systems.
  • DAI Chang-ying; ZHANG Guang-zhi
    Computer Engineering. 2009, 35(9): 139-141. https://doi.org/10.3969/j.issn.1000-3428.2009.09.048
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Current trust evaluation model exists performance problem. This paper improves the trust evaluation model which is used in Web services environment in order to improve the system performance. Consensus rule provided by the model is used to calculate a new trust degree. Independent trust degree is improved to show the different reflect of independent trust degree to final trust degree. Simulation experiments show the improvement of the model and consensus rule achieves the anticipated results.
  • LI Fei; ZHOU Yu-jie
    Computer Engineering. 2009, 35(9): 142-143,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.049
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Content Encryption Key(CEK) for stream media in DRM system is difficult to change, which is necessary from the security point. Based on OMA DRM 2.0 specification and ISO138181, MPEG 2 TS standard, a new technology for CEK switch is developed, which is implemented by switch preparation stage, key transition stage, key switch widow and rigidly accurate procession for key switch. By the new technology, CEK for steam media is switched smoothly and security of DRM system is improved without the influence to user watching.
  • DAI Hao; LIU Jia-yong; FANG Yong
    Computer Engineering. 2009, 35(9): 144-146. https://doi.org/10.3969/j.issn.1000-3428.2009.09.050
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    With Linux system call interception and loadable kernel module technique, the file filtering drive is studied and developed. And a file encryption/decryption server is implemented using blowfish algorithm on kernel-level about file filtering drive and its analysis of performance is presented. The result shows that, if the software functions are added to kernel-level, the kernel mechanism greatly improves the operation efficiency of the software and enhances the safeness on Main Machine System(MMS).
  • QIAN Meng; MAO Han-dong; YAO Li; ZHANG Wei-ming
    Computer Engineering. 2009, 35(9): 147-149,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.051
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Recent work in network security focuses on the fact that combinations of exploits are the typical means by which an attacker breaks into a network. This paper describes a new approach to represent and analyze network vulnerability. It proposes logic exploitation graph, which directly illustrates logical dependencies among exploitation goals and network configure. The logic exploitation graph generation tool builds upon LEG-NSA, a network security analyzer based on prolog logic programming, and demonstrates how to reason all exploitation paths using bottom-up and top-down evaluation algorithms in the prolog logic-programming engine. Experimental evidence show that the logic exploitation graph generation algorithm is very efficient.
  • WANG Yong-bing; MEN Yu-mei; JI Long-tao
    Computer Engineering. 2009, 35(9): 150-152. https://doi.org/10.3969/j.issn.1000-3428.2009.09.052
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Threshold signature is an important part of digital signature. Through the security analysis of a new(t, n) threshold signature scheme with a special member presented by Miao at the tenth youth communication conference, this paper proposes three kinds of forgery attacks, malicious SDC and the signaturer can forge a valid signature. An improved scheme based on the property of original scheme is proposed and the security weakness of Miao scheme is overcome. In the new scheme, the power of SDC is limited and the benefit of signaturer is protected, so it is more safety and efficient.
  • LIU Wen-yuan; ZHANG Shuang
    Computer Engineering. 2009, 35(9): 153-154,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.053
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Electronic contract signing is a practical application of the fair exchange of digital signatures. The protection problem of signers’ privacy is an important problem, which affects the application of electronic contract signing protocol. This paper proposes a new protocol to the existing problem, it succeeds in protecting signers’ privacy by signature division, verifiably encrypted signature and bilinear pairings technologies. The proposed scheme can realize not only the protection of signers’ privacy, but also high efficiency and simple structure.
  • LI Bai-liang; XU Da-cheng
    Computer Engineering. 2009, 35(9): 155-157. https://doi.org/10.3969/j.issn.1000-3428.2009.09.054
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper proposes a harr wavelet transform Image watermark algorithm based on lifting scheme. In the algorithm, the watermark is performed a m-sequence transform. It generates the secret key by performing the exclusive-or operation of watermark and the low frequency coefficient of the host image after discrete wavelet transform. After inversing discrete wavelet transform, the host image is obtained. Experimental results demonstrate that the watermark algorithm has good robustness against the attacks such as rotation, image compression, noise addition, filtering, clipping and other image processing.
  • ZHU Geng-ming
    Computer Engineering. 2009, 35(9): 158-160,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.055
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Free-riding and some malicious actions have hampered development of Peer-to-Peer(P2P) network. This paper proposes a peer reputation audit and evaluation algorithm which is based on peer transaction records and improves exist trust evaluation model. The audit and evaluation algorithm employs incentive mechanism to restrain free-riding, employ digital signature and audit to restrain diversified malicious action. Simulation experimentsal results show that the algorithm is efficient and practicality.
  • FENG Xin-yang; SHEN Jian-jing; LI Ping
    Computer Engineering. 2009, 35(9): 161-163. https://doi.org/10.3969/j.issn.1000-3428.2009.09.056
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In order to make the access to Web services more effective and safe, an access control model for Web services is presented. The model is built on the basis of the SOAP message handler chain. It can provide access control at the message level, and has better extensibility and flexibility. By means of extending handler chain, the model can meet various practical needs. A practical application in XFire framework is provided.
  • ZHANG Yu-li; CAI Qing-jun
    Computer Engineering. 2009, 35(9): 164-165,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.057
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Focusing on the problem of lack of the codes of anti-collusion fingerprinting, a new method based on the rational normal curves——the Strong Partial Balanced t-Design(SPBD) is proposed. It gets a lot of new anti-collusion fingerprinting codes from the new method. The number of those are much larger than the known, and the efficiency of the code is better than all the known codes.
  • JIN Shang-zhu; PENG Jun; YANG Zhi-ming; YOU Ming-ying
    Computer Engineering. 2009, 35(9): 166-168. https://doi.org/10.3969/j.issn.1000-3428.2009.09.058
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at encryption and decryption used by software sending and receiving data packets at lower rate, an implementary scheme with the properties of high speed, high performance and flexibility to all kinds of secure system is proposed by exploiting IPSec protocol, including ESP and IKE which can freely use special algorithm within the crypto card. The implementary IPSec models and data transmission system are tested and analyzed. Results indicate that the system proposed is distinct advantage than software encryption system .
  • LI Jia; YAO Ming-lin
    Computer Engineering. 2009, 35(9): 169-170,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.059
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at the problems of secure data transformation and private protection, this paper researches the design of improved Twofish encryption/decryption chip based on Field Programmable Gate Array(FPGA). It uses sixteen Rijndael-like S-boxes to improve the security of Twofish algorithm, and adds a pseudo random number generator to determine the S-box applied in each round, which can enhance the performance to against attacks. The improved chip is realized with FPGA Stratix EP1S20 manufactured by Altera Co., and it is proved that this method can enhance the security of the system.
  • YUAN Shu-xiong; SUN Xing-ming
    Computer Engineering. 2009, 35(9): 171-173. https://doi.org/10.3969/j.issn.1000-3428.2009.09.060
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Database watermark can embed watermark in massive data. Database watermark can provide sufficient evidences for data owners by which they can protect their ownership of assets. This paper discusses application about relational database watermark on integrated business system and the implementation procedure of the application. It discusses and analyses some evaluation results of the application. In this application, whether embedding or extracting, it scans full recorders only once, so the algorithm in this application improves efficiency greatly compared with the previous algorithm.
  • ZHOU Hai-yan; ZHAO Jian-yang
    Computer Engineering. 2009, 35(9): 174-175,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.061
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at certificate revocation problem in Public Key Infrastructure(PKI), a solution scheme based on AVL Search Tree(AVLST) is proposed. The time complexity of searching and updating of the scheme is O(lbn). A novel certificate management method is also introduced. Experimental results show this scheme is effective, and has referential value to the PKI engineering practice.
  • WANG Zhong-shan; LIU Nai-qi; QIN Ke; HAO Yu-jie
    Computer Engineering. 2009, 35(9): 176-178. https://doi.org/10.3969/j.issn.1000-3428.2009.09.062
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at on FAT32 file system, this paper emphasizes to analyze scattered fragments of disk files, and proposes a model of reassembling deleted file fragments based on PPMC algorithm. Employed Prediction by Partial Matching(PPM) is used to build a context model and compute candidate probabilities of the possible adjacency of two document fragments, and pruning technology is adopted to process gradually and reassemble a complete file. It also analyzes the hidden file named index.dat in the system.
  • XU Jian; LI Jing; ZHANG Zhao; ZHOU Fu-cai
    Computer Engineering. 2009, 35(9): 179-181,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.063
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    To solve the key distribution problems in the BF-IBE scheme, this paper proposes a new key distribution protocol based on Merkle simple key distribution protocol and Diffie-Hellman key exchange, which improves the BF-IBE scheme. A new secure E-mail scheme based on Identity-Based Cryptosystems(IBC) is designed with the combination of the improved BF-IBE scheme, GDH group signatures and key exchange protocols. It ensures not only the confidentiality, integrity and authenticity, but also the non-repudiation and tracing of the e-mail owing to the improved PKG. The new scheme is compatible with the existing mail protocols and has some practicability as well as application prospects.
  • YANG Hong-yu; LI Guan-jun
    Computer Engineering. 2009, 35(9): 182-184. https://doi.org/10.3969/j.issn.1000-3428.2009.09.064
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper presents a security mechanism aiming at security requirements of the mobile E-ticket. The security of mobile E-ticket dealing is insured by security measurement such as CA, AES, RSA and digital signature. The paper presents a mobile E-ticket system model based on the Business to Mobile(B2M). Simulation of mobile E-ticket dealing is implemented by using JAVAEE, JAVAME and XML. Experimental results demonstrate the security and feasibility of the model.
  • Artificial Intelligence and Recognition Technology
  • WU Chen-han; LUO Yu-chen; CHEN Wei
    Computer Engineering. 2009, 35(9): 185-186. https://doi.org/10.3969/j.issn.1000-3428.2009.09.065
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Route programming of grid node control is the key technique of information grid needed to resolve. This paper improves the based ant colony algorithm and proposes the route programming strategy for multi-level route optimization. The strategy not only conquers the weakness of easily running into the single route death-lock while making route optimization in the information grid, but also enhances the virtues of the ant colony algorithm of positive feedback and efficient constringency. Furthermore the strategy avoids that the algorithm ends too early or too late, which influences the whole performance of the algorithm, and the strategy can make the information grid nodes be effectively dispatched according to the task amount and route performance.
  • MU Xiao-fang; ZHAO Yue-ai; ZHANG Zhao-xia
    Computer Engineering. 2009, 35(9): 187-189. https://doi.org/10.3969/j.issn.1000-3428.2009.09.066
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    According to an online reputation grid resource management model of auction mechanism, this paper designs the global scheduling strategy of grid jobs based on the Genetic Algorithm(GA). It introduces two economy factors which are time and cost, and improves GA’s astringency. The improved algorithm can achieves the optimized resource allocation strategy on user demand, and improves the system’s performance. This algorithm is tested on the GridSim simulator, and the results prove that it is better than traditional algorithms.
  • WANG Jun-song
    Computer Engineering. 2009, 35(9): 190-191. https://doi.org/10.3969/j.issn.1000-3428.2009.09.067
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    With a large amount of network traffic data collected from the actual network, a network traffic model based on Elman neural network theory is constructed. The structure design of Elman neural network is introduced, and a leaning algorithm based on orthogonal least squares is proposed, on basis of which, the network traffic is predicted. Simulation experimental results show this model has better effect of prediction, and compared with traditional linear model and BP neural network model, it has higher precision and better adaptability.
  • LI Rong-jun; CHANG Xian-ying
    Computer Engineering. 2009, 35(9): 192-194. https://doi.org/10.3969/j.issn.1000-3428.2009.09.068
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Particle Swarm Optimization(PSO) theory is introduced. The problem of random number generating with speed renewal in PSO is researched. Three generating ways of random number in speed renewal process are numerically studied in detail by using standard test functions, and the results are explained by corresponding theories. It is helpful to understand the mechanism of PSO algorithm, and also provides the values foundation for further research.
  • CUI Shi-lin; TIAN Fei
    Computer Engineering. 2009, 35(9): 195-197. https://doi.org/10.3969/j.issn.1000-3428.2009.09.069
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at the problem of feature extracting and feature discriminate in face recognition, this paper introduces a new method of face recognition based on Scale Invariant Feature Transform(SIFT) feature and Fisher discriminant. The SIFT, with the invariant of rotation, scale, translation and illumination, can be used as a primer feature, then it uses FLD to extract the quadratic feature, by comparing the Euripides distance of the quadratic feature. It can find right class of the test picture. Practice illustrates that the recognition rate of new method is 99.65%, which exceeds FLD and KFLD, and the recognition speed of new method is corresponding to Fisher methed.
  • LI Jin; LUO Yi-ping; LIU Hai-hua; GAO Zhi-yong
    Computer Engineering. 2009, 35(9): 198-200. https://doi.org/10.3969/j.issn.1000-3428.2009.09.070
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at the problems existed in traditional Linear Discriminant Analysis(LDA), a novel method for face recognition based on improved null space approach is proposed. The projection of within-class scatter vector on the null space is conducted with singular value decomposition by using the stability of singular vector. The singular value is also conducted with measure of treatment. The performance of this method is tested in both ORL and Yale face databases. Experimental results show this method is effective and achieves higher recognition rate.
  • HUANG Lv-e; LI Ping-kang; DU Xiu-xia
    Computer Engineering. 2009, 35(9): 201-203,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.071
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper designs a new system of motion video tracking motion human body, and the tracking platform which is based on P89v51 is simple and stable. A fast model matching way is presented on motion object detection and tracking. In the complex motion background, it adopts the adapting Surendra background updating algorithm for capturing the background image and subtracting the target template, then decreas the model matching area by the same area of before and after frame. It is realized in video automatic tracking of motion human body at real-time video meeting.
  • HU Peng-yu; ZHAO Peng-peng; FANG Wei; CUI Zhi-ming;
    Computer Engineering. 2009, 35(9): 204-207. https://doi.org/10.3969/j.issn.1000-3428.2009.09.072
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In order to get valuable information from the mass Deep Web, this paper proposes a quality estimation model of Deep Web data sources, considering the query capability of interface, the quality of interface pages and the Quality of Services(QoS), using the SVM and Ranking SVM machine learning approach to obtain the quality estimation function. Experimental results show the Kendall’s&#61556; distance between data sources quality sort sequences made by this quality estimation function and the artificial one is more than 0.5, and achieves higher accuaracy.
  • SUN Wei; ZHANG Zhi-sheng; SHI Jin-fei
    Computer Engineering. 2009, 35(9): 208-210,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.073
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    There is a disadvantage in the present simulative system of educational robot that the physical simulation is lack of support to sound. In order to make the simulation more lifelike, it is necessary to devise a sound system. According to the requirement analysis on sound and the characteristics of FMOD sound engine, its realization flow is designed. The discussion focuses on its key issues and corresponding solutions. The test results show that the devised system can realize various kinds of sound effect, which meets the needs for sound in physical simulation of educational robot. Furthermore, it can manage multiple sound sources well, and save the computer resource effectively.
  • WANG Wen-bin; ZHONG Sheng
    Computer Engineering. 2009, 35(9): 211-213. https://doi.org/10.3969/j.issn.1000-3428.2009.09.074
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In terms of the inadequacy of Multi-Objective Evolution Algorithm(MOEA) with the crowding-distance truncation operator to preserve the distribution and the deficiency of the distribution that is hard to get near to the true Pareto front under the binary condition, an improved MOEA is proposed. The improved algorithm includes the improved crowding-distance truncation operator and the self-adaptive mutation operator. Compared to other classical MOEA, experiment analysis proves that the improved algorithm achieving the final Pareto solutions qualified the better convergence and the good distribution to the true Pareto front.
  • SHEN Ren-dao; LI Shao-fa; JIANG Zhuo-lin
    Computer Engineering. 2009, 35(9): 214-216,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.075
    Abstract ( )   Knowledge map   Save
    For most video text is rich in edge, uniform-colored and horizontally ranged, the candidate text areas in video image are determined by using a fast deriche edge based algorithm, and the accurate binary text images are extracted from the areas by using a color based algorithm. The experimental results show that the method is effective in text extraction in complex-background video frame, and has higher processing speed and better extraction result in comparison with color alone based method.
  • WU Xiao-lan
    Computer Engineering. 2009, 35(9): 217-219. https://doi.org/10.3969/j.issn.1000-3428.2009.09.076
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In online retail, the conflict between the different interests of all customers to different commodities and the commodity classification structure of Web site will make customers access overabundant Web pages. To solve this problem, the data about the customers’ interests are mined to make the Web site adjust its structure, which is adaptive site. Based on improvement of the cellular automaton model using the PageRank algorithm, it achieves the adaptive adjustment and spents less time.
  • CHU Ping; WANG Kang-tai
    Computer Engineering. 2009, 35(9): 220-221,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.077
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Based on genetic algorithm and the extremal optimization idea, this paper propose an extremal genetic algorithm to deal with the QoS multicast routing. The non-equilibrium of extremal optimization can avoid to local minimums and accelerate convergence. According to the characteristics of the networks, a suit of special encode, crossover and mutation is used to guarantee the feasibility of the solution. Simulation results indicate that this algorithm has better performances on both speed and precision.
  • REN Xiao-dong; ZHANG Yong-kui; XUE Xiao-fei;
    Computer Engineering. 2009, 35(9): 222-224. https://doi.org/10.3969/j.issn.1000-3428.2009.09.078
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Traditional Adaptive Topic Tracking(ATT) uses VSM to express a topic model and bring mistaken feedback to topic model updating. This paper presents an Adaptive Tracking Technique based on K-Modes clustering(K-MATT) to solve the problems caused by traditional topic model expression. This method uses Topic Kind Center(TKC) to substitute topic model and uses named entities VSM to express TKC, updates TKC in topic tracking until TKC is stable. Experiments prove K-MATT method is effective.
  • LIU Peng-fei; DONG Shou-bin; CAO Yi-cheng; DU Zheng-ping
    Computer Engineering. 2009, 35(9): 225-226. https://doi.org/10.3969/j.issn.1000-3428.2009.09.079
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    To optimize multiple cost functions better, a multi-objective simulated annealing algorithm is proposed. In the process of operation, the multiple objectives are optimized. The optimal solutions of different directions on boundary are obtained. The structure of non-coding RNA is introduced in process of evolution. On the basis of this, the multiple comparison and prediction parallel model is presented. Experimental results show this model can promote the accuaracy and diversity of the solutions.
  • Multimedia Technology and Application
  • LIU En-hong; ZHOU Bing; GE Bao-shan; LI Xiao-dan;
    Computer Engineering. 2009, 35(9): 227-229. https://doi.org/10.3969/j.issn.1000-3428.2009.09.080
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    With the advantages of low-cost, high-performance and steady operation, embedded video servers dominate the video surveillance market. This paper presents an architectural scheme of the video encoder based on the multi-media processor Hi3510. The architecture of this encoder and its main functional modules are introduced, and the solutions to timing matching and signal integrity are detailed. Experimental results show that this encoder meets practical requirements.
  • HUANG Xue-li; ZHOU Bing
    Computer Engineering. 2009, 35(9): 230-232. https://doi.org/10.3969/j.issn.1000-3428.2009.09.081
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    To reduce the complexity of H.264 encoder, this paper proposes a novel algorithm for fast inter-frame mode decision. The encoding mode of the current macro-block is checked whether it is a skip mode in terms of its characteristics. The number of encoding modes can be reduced, and the encoding modes can be further cut down according to the relationship of the mode decision and the quantization parameter. Simulation results show that this algorithm can reduce the encoding time from 31.7% to 75.3% with almost the same image quality and compression efficiency.
  • LUO Yi-ping; SHU Zhen-yu; LIU Hai-hua; GAO Zhi-yong
    Computer Engineering. 2009, 35(9): 233-235. https://doi.org/10.3969/j.issn.1000-3428.2009.09.082
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Motion estimation is a critical problem in video encoding, which directly affects the speed and quality of the encode. According to the motion vectors of the adjacent blocks, each frame of the sequences is divided into three regions. Then the different ways of the prediction methods and search strategies are used in different regions. An improved motion estimation algorithm is proposed. Experimental results show that the algorithm is better both at the image quality and the reduction of the number of search points.
  • CHEN Fang; LI Wei; LI Xiao-qiang
    Computer Engineering. 2009, 35(9): 236-237,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.083
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The main purpose of digital music fingerprint extraction is to establish an effective mechanism used to compare the auditory quality between two pieces of audio. This paper presents a music fingerprint extraction algorithm based on wavelet packet best-basis decomposition. It uses wavelet packet coefficients related to radio content as the feature to extract fingerprint. Experimental results show that this algorithm is robust against common audio signal operations like MP3, WMA and RM compression, noise addition, and audio processing in Stirmark for audio. This algorithm exhibits high ability to differentiate between different songs.
  • CHEN Xing; DUANMU Chun-jiang; ZHANG Yu; ZHOU Shui-hong
    Computer Engineering. 2009, 35(9): 238-240. https://doi.org/10.3969/j.issn.1000-3428.2009.09.084
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at the time-consuming problem of existing motion estimation in H.264/AVC encoder, this paper proposes a new fast motion estimation algorithm based on multi-template. It divides the current block as a quasi-stationary, slow motion, or fast motion block. According to the different motion block types, different search templates and strategies are employed. Experimental results demonstrate that this algorithm raises the encoding speed with about the same image quality.
  • Engineer Application Technology and Realization
  • ZHOU Xin-dong; ZHU Ying; ZHU Ming-ri
    Computer Engineering. 2009, 35(9): 241-242,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.085
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at influence of noise and interference in computer control in process of automatic cane-sugar bowking, based on the technology of supersaturated and non-contact microwave sensing detection and wireless data transmission, this paper puts forward the technical scheme of noise cancellation, and researches into double-treating data sampling, which adopts cubical smoothing algorithm with five-point approximation. Field tests prove it has good performance. This scheme is effective and has important value for designing new product line and advancing the technique of cane sugar manufacture.
  • HE Wei; LIN Ying-cheng; ZHANG Ling
    Computer Engineering. 2009, 35(9): 243-245. https://doi.org/10.3969/j.issn.1000-3428.2009.09.086
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper uses SOPC technology and Altera corporation’s EP1C12Q240C8 as master chip to design a time synchronous data collection system. This system can be applied to real-time monitoring the components in a large aircraft, and all aspects of synchronous detection before rocket launch. It completes the clock synchronization between units based on NIOS II, and a set of flexible control and high speed self-defined internal parallel bus design.
  • GAO Xiao-rong; LI Qi; XU Ying-zhuo
    Computer Engineering. 2009, 35(9): 246-248,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.087
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at the lack of traditional information revelation manner and working manner, this paper proposes a virtual environment for visualization cooperative geosteering drilling constructed by the technology of virtual reality, CSCW and Agent. It provides a cooperation working platform for drilling workers and experts in different place to improve drilling ratio. The architecture and main technology of the virtual environment are described, including 3D visualization of drilling objects, communication between sever and client, management of cooperative partners and concurrent control of multi-user.
  • LIU Zhen; YIN Hong-sheng; ZHANG Kai; WU Jian
    Computer Engineering. 2009, 35(9): 249-251. https://doi.org/10.3969/j.issn.1000-3428.2009.09.088
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Coal mine enterprises integrated network is not able to meet business Quality of Service(QoS) requirements. This paper proposes a model for resolving the QoS problem of coal mine integrated network, by analyzing coal mine enterprises network’s business characteristics and using QoS control thought. It researches the grading data methods, the queue management algorithms and packet scheduling algorithms adapting to coal mine integrated network. Simulation results show that the model can improve the QoS of coal mine integrated network.
  • Developmental Research
  • HE Zai-hong; QUE Qing-xian
    Computer Engineering. 2009, 35(9): 252-254. https://doi.org/10.3969/j.issn.1000-3428.2009.09.089
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    A similarity model of the multi-host system volume sharing in the network computation mode is proposed to solve the rewritten condition of a few isomorphic hosts. A kind of marking left on the rewritten Similar Collection Element(SCE) of the sharing system volume to carry on the information which instructs the host itself and other hosts to locate fleetly the SCE. The host system volume sharing algorithm is designed based on two degree partial characteristics. The time complex of this algorithm’ is O(1) throughoutly. Experiment result shows that the multi-host system volume sharing strategy takes on a favorable performance and stability.
  • FAN Jing; DONG Tian-yang; YU Qing
    Computer Engineering. 2009, 35(9): 255-257. https://doi.org/10.3969/j.issn.1000-3428.2009.09.090
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In order to render the complicated and large-scale scene of virtual forest rapidly, this paper proposes a framework of the multiple layer scene engine for the virtual forest after analyzing the characteristic of the virtual forest simulation. Some key technologies of the multiple layer scene engine, such as the multi-resolution terrain generation and the algorithm of model simplification are presented. The virtual forest system is implemented and the multiple layer scene engine is applied in this system. Application result shows that the multiple layer scene engine can increase the efficiency of rendering the virtual forest and meet the demand of real time cruise in the virtual forest.
  • LI Qing-cheng; PENG Jie; GONG Xiao-li; LIU Jia-xin
    Computer Engineering. 2009, 35(9): 258-260. https://doi.org/10.3969/j.issn.1000-3428.2009.09.091
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Concerning the effective reading of HTML document on handheld mobile devices, design and implementation of an embedded application-oriented, platform-independent HTML document parser, and its key technologies are described and analyzed. It presents Screen Matching Detection(SMD) mechanism to filter void content of current screen reading. Experimental results show that the parser reduces the requirements of the embedded system processing capabilities and memory configuration, and meets the needs of handheld reading device.
  • ZHANG Hai-li; YANG Min
    Computer Engineering. 2009, 35(9): 261-264. https://doi.org/10.3969/j.issn.1000-3428.2009.09.092
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Aiming at the limitation of the content pushing based on conventional request-response working model, a bluetooth based content pushing system is proposed. The architecture, the key process of initiative content pushing and the design and implementation of content server, wireless access point and mobile client are presented. Three major working models of wireless node and the anti-spamming process are discussed, it shows the advantage of the system in application deployment and user experience.
  • XU Zheng; SHEN Xiao-yun; HAN Dan
    Computer Engineering. 2009, 35(9): 265-268. https://doi.org/10.3969/j.issn.1000-3428.2009.09.093
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    This paper discusses techniques to build the database of civil aviation flight visualization by using the professional modeling tool MultiGen Creator, and gives the optimization techniques for some typical models. With the telemetric data and fieldworking data, a flight visualization database of a western China airport is built. Experimental result suggests that the database performs well with reality and real-time characteristic, and meets the requirement of flight training.
  • JIANG Yi-lian
    Computer Engineering. 2009, 35(9): 269-271. https://doi.org/10.3969/j.issn.1000-3428.2009.09.094
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    According to the defect of transfusion speed monitoring system, this paper proposes a new design idea based on embedded Linux for transfusion speed monitoring system, which adopts wireless detection model and monitors the state of the transfusion of the patients in the WLAN. The functions of the system include transfusion speed monitoring, wireless data transformation, data processing system, transfusion abnormality warning and so on. Application result shows that the system is easy to enforce and has good expansibility.
  • ZHAI Yong; XU Jin
    Computer Engineering. 2009, 35(9): 272-274. https://doi.org/10.3969/j.issn.1000-3428.2009.09.095
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In order to improve identification speed of Radio Frequency(RF) tags, this paper proposes an improved anti-collision algorithm called ODFSA(Optimized Dynamic Framed Slotted ALOHA). The algorithm judges the relationship between the number of tags and the algorithm threshold, and selects the number of responding tags which equivalents to the largest slot number of Radio Frequency Identification(RFID) system until the number is less than the threshold, and enters Dynamic Framed Slotted ALOHA(DFSA) algorithm. Simulation results show that the efficiency of ODFSA algorithm is 1.488 and 1.375 times than Basic Framed Slotted ALOHA(BFSA) algorithm and DFSA algorithm when the number of tags is 500, and the efficiency of this algorithm is very close to the theoretical value in the circumstance of the large number of tags.
  • LIU Han-fei; CHENG Jian; QIAN Yu-liang
    Computer Engineering. 2009, 35(9): 275-276,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.096
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The impedance matching is an essential part of a RF system in order to avoid reflections and optimize the operation of the generator. The discussion about matching algorithm based on gradient information of reflection coefficient magnitude is made. This paper presents the structure of automatic impedance matching apparatus briefly. To improve the performs of matching algorithm, a new method of automatic impedance matching is introduced.Comparison with both methods is made and result shows that the new approach can dramatically curtail the time of impedance matching.
  • HUANG Shen-xi; FAN Xiao-ping; LIU Shao-qiang; PENG Chun-hua; YANG Sheng-yue
    Computer Engineering. 2009, 35(9): 277-279. https://doi.org/10.3969/j.issn.1000-3428.2009.09.097
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The traditional special testing system for high-speed Analog Digital Converter(ADC) is very difficult to be constructed and its cost is also very high. To overcome these shortcomings, this paper puts forward a kind of low cost high-speed ADC frequency-domain characteristics testing system based on window-added and interpolated FFT algorithm, and gives out some key design technologies such as the driving circuit of ADC’s sampling clock, the driving circuit of ADC’s input signal, FIFO buffer circuit and USB interface circuit.
  • FU Guo-qing; QI Zheng-wei; LIANG A-lei
    Computer Engineering. 2009, 35(9): 280-282,. https://doi.org/10.3969/j.issn.1000-3428.2009.09.098
    Abstract ( )   Knowledge map   Save
    This paper raises 3S system concept in the view of Geographic Information System(GIS)/Global Positioning System(GPS)/Location Based Service(LBS) applications, analyzes why 3S system flourishes and the scenarios it applies to, proposes architecture design of typical 3S system, and discusses critical technical problems of implementating 3S system such as map format, map matching, route navigation, platform independency and so on. It demonstrates the prototype of a 3S system developed for Shanghai Expo in 2010.
  • JIANG Ling-yan; LIANG A-lei; GUAN Hai-bing
    Computer Engineering. 2009, 35(9): 283-封三. https://doi.org/10.3969/j.issn.1000-3428.2009.09.099
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In binary translation, the use of intermediate representation can appropriate segregate different machine platforms, and make binary translation system more portable. This paper presents an intermediate representation called VINST, introduces the instruction set and its characteristics. It discusses some optimization methods including SSA formalization algorithm and redundancy elimination algorithm. Through comparison between before and after the optimization, it shows that a simple and efficient method can cover the cost of optimization itself and improve system performance.