Loading...
  • 中国计算机学会会刊
  • 中国科技核心期刊
  • 中文核心期刊

Current Issue

    • 论文
      IRC Botnets’ Size Measure Based on Duplicated Removal of Dynamic IP
      LI Runheng,GAN Liang,JIA Yan,LI Aiping,YANG Shuqiang
      2012, 34(9): 1-7. doi:
      Abstract ( 328 )   PDF (1182KB) ( 418 )     

      IRC botnet can be regarded as a collection of compromised computers under the commandandcontrol infrastructure constructed by the IRC server. Since both the botnet and the IP are dynamic, the measure of botnet’s size is difficult. The paper removes the duplicated and dynamic IP to estimate the size of the botnet. Experiments are carried out for validation purposes.

      Design and  Implementation of Esper &Nagios Based Network Monitoring System
      CAI Zhaoquan,SUO Jian,WANG Huabin,LU Qingwu,LUO wei
      2012, 34(9): 8-12. doi:
      Abstract ( 299 )   PDF (791KB) ( 304 )     

      To address the issue of the increasing massive and complicated internal network application of the enterprises, we propose a system network monitoring platform with the combination of Esper and Nagios. This platform will apply the event flow technology to the network security event control by using the strategy analysis and rule engine to actively handle the network security events. As a result, it supports the large scale dynamic network event decisionmaking analysis with high efficiency. It can realize the active warning and real time passive notification before and after the event. Thus, it avoids the solidified effects caused by the static monitoring and supervision system, and updates the dynamic setting of the rule with the capacity of meeting the business needs of the enterprises perfectly.

      A Strategy of Preventing Routing Attacks in Mobile Ad Hoc Networks Based on Genetic Algorithm
      YANG Hui,ZHONG Sheng
      2012, 34(9): 13-16. doi:
      Abstract ( 324 )   PDF (673KB) ( 306 )     

      In wireless mobile networks,the malicious nodes can attack networks by sending false information and false routing information,broadcasting false links,etc.Based on the analysis of several common routing attacks,a genetic algorithm based routing optimization strategy is proposed. The experimental results indicate that this strategy can prevent routing attacks effectively and improve network performance.

      An Improved TRW Algorithm Based on Packet Sampling
      ZHANG Hai,ZHANG Jian,DAI Shaofeng
      2012, 34(9): 17-20. doi:
      Abstract ( 302 )   PDF (411KB) ( 390 )     

      The portscan is most popular anomaly in the network and the TRW is the most representative algorithm for the portscan detection.The packet sampling is currently the majority of packet selection method used by many business demands.Prior work has shown that the packet sampling thins traffic flows and impacts anomaly detection.The success ratio and the false negative ratio of the TRW initially increases for low sampling intervals before dropping off for high sampling intervals as the traffic is increasingly thinned.Based on previous researches,we design an improved TRW using theTCP protocol information in the sampling packet.Experimental results show that using the algorithm the false negative ratio drops off while the success ratio does not change.

      Research on a Wireless Network System in the Intelligent Office Environment
      WANG Haizhen1,LIAN Zuozheng2,TENG Yanping1
      2012, 34(9): 21-25. doi:
      Abstract ( 281 )   PDF (511KB) ( 361 )     

      The currently network in the domestic construction is installed by wires,which is not easy to extend,therefore,in order to improve the intelligence of controlling the building environment,and provide a comfortable,energyefficient office environment,the problem of the wireless network system construction in the intelligent office environment is studied and a wireless network system is proposed based on the multi Agent technology, the ZigBee technology and the fuzzy Qlearning algorithm.The system network structure and the multiAgent system model are designed, and then the design and communication methods of each Agent are analyzed, and both the system hardware and software platforms are designed.Finally,the experiments are carried on. On the one hand, we verify that whether multiAgent fuzzy Qlearning can speed up the learning process or not;on the other hand,a program for system network performance test is designed and the test results show that the network packet loss rate is low.Therefore, the system can be applied.

      Performance Improvement of BDDbased Network Reliability Analysis Algorithm
      PAN Zhusheng,MO Yuchang,ZHONG Farong,ZHAO Jianmin
      2012, 34(9): 26-32. doi:
      Abstract ( 267 )   PDF (615KB) ( 317 )     

      BDD is a diagrammatic representation of the Boolean function and has been widely applied to the network reliability analysis.In order to enhance the performance of network reliability analysis algorithm based on BDD,this paper first puts forward two kinds of invalid edge expansion paths according to the edge expansion diagram instance:invalid edge expansion with redundant nodes and invalid edge expansion with ST unconnectedness.Then,useful techniques are provided to successfully eliminate those invalid edge expansion paths.Experimental results show that these techniques can identify the invalid paths in advance,avoid invalid extension,reduce the number of intermediate subnetworks and shorten the analysis time.With these two techniques,both of the invalid expansion paths can be eliminated,and hence great performance improvement of network reliability analysis is achieved.

      Investigation of the Parallelization of theFractionalStep Method to 3D IncompressibleNavierStokes Equations on Heterogeneous Platforms
      XU Ying,XU Lei,JIANG Kai
      2012, 34(9): 33-39. doi:
      Abstract ( 267 )   PDF (697KB) ( 279 )     

      This paper implements the classical fractionalstep method for 3D incompressible NavierStokes equations in parallel using message passing interface (MPI),and investigatesthe mapping of parallel algorithm on the GPGPU heterogeneous platform usingCUDA.The momentum equation is solved with BiCGSTAB algorithm and the pressure Poisson equation is directly solved with the Fourier method. With the analysis of the computation and communication ratio on each MPI processorsfrom 1D,2D and 3D domain decompositions,the 2D domain decomposition is found to have the smallestcomputation and communication ratio and is chosen in this study.The performance results for the CPU clusters and GPGPU platform are discussed.

      Scheduling Strategy for DeadlineSensitive Scientific Workflow on Hybrid GridCloud Infrastructure
      YAN Chaokun1,2,HU Zhigang1,LUO Huimin2
      2012, 34(9): 40-46. doi:
      Abstract ( 287 )   PDF (752KB) ( 321 )     

      In a hybrid gridcloud environment,the user has elasticity provided by public cloud resources that can be aggregated to the existing grid resource pool as necessary.However,the integration opens new problem,such as:which are the best resources to loan from a public cloud based on current QoS requirement?Existing scheduling strategies based on static resource information cannot absolutely guarantee the successful completion of scientific workflow and satisfy the user’deadline requirements.In this paper,we propose an infrastructure,which is able to manage the execution of scientific workflow. Aimed at the scheduling of deadlinesensitive scientific workflow,the stochastic service model is adopt to model dynamic service capacity of grid resource and a metric called Default Risk of Task (DST) is offered to judge whether virtual resources should be loaned from cloud providers or not.Thus a scheduling algorithm (HCA_SASWD) is put forward.The experimental results show that HCA_SASWD achieves better performance than other algorithms on user’s deadline guarantee.

      Research onCopy State SavingTechnique in Parallel Simulation
      WANG Xuehui1,CAO Lu2,ZHANG Lei3
      2012, 34(9): 47-50. doi:
      Abstract ( 251 )   PDF (619KB) ( 275 )     

      The optimistic time synchronization mechanism can dramatically improve the parallel simulation performance,but the optimistic time advancement will lead to causality error,which needsthe event rollback according to the saved state,therefore the state saving mechanism is an important factor impactingthe optimistic time advancement performance.In this paper,we first introduce the logic process execution procedure of the parallel simulation and discuss the state saving and event rollback mechanism for the optimistic time advancement;then we model and theoretically analyze the copy state saving technique,and test its performance through experiment tovalidatethe correctness of our theoretical analysis.

      Research on P2P Database System
      LIU Dong1,2
      2012, 34(9): 51-57. doi:
      Abstract ( 263 )   PDF (498KB) ( 278 )     

      Due to having many benefits,the emerging P2P is attracting the attentions of industries and academia.Data sharing is one of the P2P application domains.However,the data sharing in current P2P systems is mostly restricted to filesystemlike capabilities, and cannot directly deal with relational data.Furthermore,under some situations,data integration methods in the traditional database cannot be carried on.The mergence of the P2P and the database technology provides a new approach to solving the problem.In this paper, firstly we introduce the backgrounds of the emergence of PDBS (P2P Database System) and its related work.Secondly,we simply review the P2P technology from two aspects:character and overlay network.Thirdly,we analyze the similarities and differences between PDBS and DDBS (Distributed Database System).Finally,we also present a PDBS prototype instance:PeerDB.

      A Delay Model of Adaptive Channel Double Buffers for OnChip Interconnects
      QI Shubo,LI Jinwen,YUE Daheng,ZHAO Tianlei,ZHANG Minxuan
      2012, 34(9): 58-63. doi:
      Abstract ( 281 )   PDF (891KB) ( 304 )     

      With the technology scaling down,relative to the gate delay, the global wire delay increases and hence a flit transmission between routers requires several cycles on NetworkonChips(NoCs).Registers in pipelined channels cannot buffer flits when the congestion occurs in the creditbased flow control scheme.Therefore,an adaptive Channel Double Buffer (CDB),which can buffer flits,is proposed in the paper. With detailed design and analysis of the gatelevel circuit, the delay model of the CDB is derived based on the theory of the logical effect.It is validated by Synopsys Prime Time in a TSMC 65 nm technology and found the difference within one τ4.Experimental results show that the depth of the CDB is the same with the SPLS for a 1mm semiglobal interconnect wire in a 32nm technology.

      Memory Access Behavior CharacteristicsOriented Cache Partition for SPMV
      DENG Lin,DOU Yong,ZHENG Yi
      2012, 34(9): 64-70. doi:
      Abstract ( 329 )   PDF (1376KB) ( 286 )     

      The sparse matrix vector multiplication (SPMV) is the kernel of many scientific applications.Due to its indirect and random memory accesses,the SPMV is the bottleneck of scientific applications.In this paper,based on analyzing data structure and computation process,we present the memory access characteristics of the SPMV and propose a memory access behavior characteristicsorient cache partition method.According to the performance evaluation with 12 sparse matrix vector multiplications,the proposed cache partition method increase the hit ratio of reusable data and reduce the cache capacity request efficiently during the SPMV.

      Design and Implementation of a LowCost 128bit QuadruplePrecision FloatingPoint SIMD Fused MultiplyAdd Unit
      HUANG Libo,WANG Zhiying,SHEN Li,MA Sheng
      2012, 34(9): 71-76. doi:
      Abstract ( 313 )   PDF (873KB) ( 279 )     

      Incorporating the SIMD unit has become one of the important ways to improve the performance of processors.The reused lowcost hardware design method for the fixedpoint SIMD unit is mature,but it is not the case for the floatingpoint SIMD unit,which still remains the simple replication design method. To address the increasing computation demand for 128-bit quadrupleprecision floatingpoint operations,this paper proposes the hardware design of the lowcost 128bit quadrupleprecision floatingpoint SIMD fused multiplyadd (FMA) unit.The experimental results show that the structure of the proposed FMA unit can be more optimized in performance and cost parameters in comparison to the traditional 128bit quadrupleprecision floatingpoint SIMD multipleadd unit.

      Uncertainty Measurement and Visual Analysis on Terroristic Attacks Data
      HE Huaiqing,WANG He
      2012, 34(9): 77-82. doi:
      Abstract ( 276 )   PDF (594KB) ( 423 )     

      In recent years,terroristic activities occur more frequently and have seriously affected the regional stability and the world peace.With the development of information technology,the researchers are able to obtain information of terroristic attacks from many aspects.However, with the constant enlargement of the scale of data sets,how to explore the underlying information and analyze the uncertainty from a large number of data has become an important issue in the analysis process of terroristic attacks.On Global Terrorism Database,based on visual analysis and uncertainty measurement theory,we propose the measurement and visual analysis methods on data records and uncertainty of attributes.By integrating results of uncertainty measurement with parallel coordinates,histogram,area chart and interactive methods,the data uncertainty is clearly displayed without influence on its representation and provides information base for situation assessment based on uncertainty theory the next step.

      Biological Visual Characteristic Based Infrared and Visible Image Fusion Scheme
      LI Min,CAI Wei
      2012, 34(9): 83-87. doi:
      Abstract ( 258 )   PDF (750KB) ( 355 )     

      The Pulse Coupled Neural Network (PCNN) model of the cat visual cortex has proven to have interesting properties in image processing,including segmentation,target recognition et al.This paper proposes a multisensor image fusion scheme based on the modified PCNN.Focusing on the famous difficult problem of PCNN and how to determine PCNN parameters adaptively,this paper brings forward an adaptive PCNN parameters determination algorithm based on water area.Experimental results demonstrate that the proposed fusion scheme outperforms the multiscale decomposition based fusion approaches,both in visual effect and objective evaluation criteria.The research fruits have certain value on the theory research and practical application of PCNN.

      Pulse Signal Denoising and Feature Point Extraction
      CAI Xiao1,QIN Xiaozhen1,KANG Shuangshuang2
      2012, 34(9): 88-92. doi:
      Abstract ( 249 )   PDF (906KB) ( 434 )     

      By utilizing the wavelet transform which has an ability to reveal lowfrequency signal and highfrequency signal, the powerfrequency and baseline wander interference in pulse signal is eliminated.The signal period is detected with the reconstructed detail signal.Every pulse period can be drawn up with spline fitting.The feature points of the denoised signal are detected with the first derivative of the spline fitting function and the integral function.At last we find out the relationship between the feature of the pulse and the physiological significance.

      A Rectification Method Based onLocal Perspective Transformation forPDF417 Barcode upon Cylinder Side Surface
      HUANG Shuhai,YIN Jianping,ZHU En,TANG Xiangen
      2012, 34(9): 93-97. doi:
      Abstract ( 275 )   PDF (621KB) ( 352 )     

      The PDF417 barcode,as one of the widely used twodimensional barcodes,is being applied to various kinds of goods.There are few researches on the recognition of the PDF417 barcode upon cylinder side surface,though goods in cylinder shape are common in life.To rectify the PDF417 barcode,an algorithm based on local warp perspective transformation is proposed.The PDF417 barcode upon cylinder side surface is segmented into several sub areas first,then the perspective transformation will be done on these sub areas.Finally, these sub areas are joined together and the rectified barcode is obtained.Experimental results show that this algorithm can effectively transform the PDF417 barcode upon cylinder side surface into one upon plane,so that the contained information can be decoded successfully.

      Uyghur Text Segmentation in Color Image with a Complex Background
      Mariyemuguli·Mijiti,Halidan·A
      2012, 34(9): 98-103. doi:
      Abstract ( 252 )   PDF (672KB) ( 256 )     

      Writing along the baseline and with a large number of additions is one major characteristic of Uyghur, therefore the line and word segmentation and recognition of Uyghur in a complex color image becomes a difficult but interesting problem.In the paper,firstly,the complex color image is changed to be a grayscale image.Secondly,the color image is changed to be a grayscale edge image and further a binary image of partial area.Then after regional detection and edgeadjusting,the line position of the Uyghur is located.According to the line position,the text line is obtained from the image.Finally,based on the segmentation result,the accumulation of pixels along the horizontal and vertical line is analyzed to find the best cutoff points and separate out the individual letter or the letter section contains several letters in a text line.Experimental results show that the line segmentation accuracy can reach 96% and the word segmentation accuracy can reach 98%.

      A Search Algorithm for Multidimensional Data
      ZHONG Sheng,ZHONG Xiaoshuang,YU Yancong
      2012, 34(9): 104-108. doi:
      Abstract ( 293 )   PDF (678KB) ( 378 )     

      This paper proposes a data structure that uses the binary tree to organize multidimensional data.Based on the proposed data structure,an area search algorithm is proposed in order to find out all points in the given data set in the domain of given points.The search efficiency of the algorithm is not related with the space dimension.The average time complexity of the algorithm is O(logn).To guarantee the algorithm efficiency,the paper also proposes a balanced tree adjustment algorithm.

      Optimization for the Urban Transit RoutingProblem Based on the Genetic Algorithm
      ZHAO Yi,ZHONG Sheng
      2012, 34(9): 109-112. doi:
      Abstract ( 308 )   PDF (620KB) ( 416 )     

      Without considering setting bus stops,the urban transit network design problem can be mainly divided into two parts:one is the urban transit routing problem and the other is the urban transit scheduling problem.The former involves the development of efficient transit routes on an existing transit network with predefined bus stops.The latter takes charge of assigning the schedules for the passenger carrying vehicles.This article only focuses on the former.An optimization method based on the genetic algorithm is proposed to find out the optimal bus route set.The experiment shows that the results have been greatly improved,compared with some traditional methods.