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• 2010, No. 10　Published:29 September 2010 Last issue    Next issue
  Columns in this issue: 论文

• 论文

  An Irrelative Rule Set Match Algorithm Based on Collision Detection

  SHI Ronghua1,MO Rui1,ZHAO Wentao2

  2010, 32(10): 1-4. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 400 )   PDF (550KB) ( 459 )   　　

  The fire wall has already become a key role in the network security architecture,and more and more attention has been paid to the management of firewalls. This paper aims at the problems of rule collision and rule match efficiency in the management of firewalls,and submits an irrelevant rule set match algorithm based on  collision detection. By analyzing  the filtering rules,the paper confirms 5 relations that the rules should be matched;by categorizing  the collision rules,the paper concludes the collision detection state diagram according to the collision's characteristics,which helps to optimize the firewall rule set. Based on the analysis of the traditional liner match algorithm and the tree match algorithm,the paper submits an irrelative rule set match algorithm based on collision detection.The efficiency of the algorithm is O(log(n)) on the average and the performance of the algorithm is better than the traditional ones.

  Research and Implementation of the Hierarchical RFID Code Resolution System

  LIU Wei,CHEN Xiaohui,XIE Peng,YUAN Wei

  2010, 32(10): 5-7. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 404 )   PDF (740KB) ( 338 )   　　

  The architecture of the RFID code resolution system has significant impacts on the performance of the RFID code resolution system. This paper analyzes the existing RFID code resolution technologies,and then proposes a hierarchical RFID code resolution service.The system architecture,data storage and cache mechanisms are fully discussed. System test shows that the proposed system improves the resolution performance significantly,offering effective code resolution services.

  Research of Quantitative Vulnerability Assessment Based on Attack Graphs

  CHEN Feng1，ZHANG Yi1，BAO Aihua2，SU Jinshu1

  2010, 32(10): 8-11. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 605 )   PDF (444KB) ( 353 )   　　

  Attack graph is a modelbased vulnerability analysis technology. It may automatically analyze the interrelation among vulnerabilities in the network and the potential threat resulting from the vulnerabilities，which is one of problems the quantitative vulnerability assessment must solve. This paper proposes a novel quantitative vulnerability assessment method based on attributebased attack graphs. First attributebased attack graphs and valid attack paths are formally described， and maximal reachable probability is adopted to measure the vulnerability of the key attribute set of the target network. An algorithm for computing maximal reachable probability is presented to solve the problem of loop attack paths. Finally， because some data may not be obtained in practical assessment，the conception of creditability is introduced to measure the impact of absent data on the result.

  Degrees of the Wireless Sensor Network with Arbitrary Sensing Areas

  FAN Gaojun,JIN Shiyao

  2010, 32(10): 12-15. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 430 )   PDF (446KB) ( 517 )   　　

  The coverage is a fundamental research issue in WSN because it can be considered as the measure of QoS of the sensing function for a sensor network. In order to evaluate the coverage degrees of the wireless sensor network with arbitrary sensing areas,we transform the area coverage problem to the intersection points’ coverage problem based on regional closeness and computational geometry techniques. An algorithm for calculating the coverage degrees is proposed by analyzing the set of intersection (SI) inside or onto the boundary of the coverage region,and SI includes:(1) the intersecting points or the two end points of the intersecting lines of any two boundaries of sensors; or (2) the intersecting points or the two end points of the intersecting lines between any boundary of a sensor and the boundary of  the coverage region. The coverage degrees of wireless sensor networks are identical to the minimal coverage degrees among SI.

  Security Evaluation Based Dynamic  Access  Control  for Grid Application

  YAN Lei，TANG Weimin，WANG Zongfei

  2010, 32(10): 16-19. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 419 )   PDF (404KB) ( 276 )   　　

  The emerging Grid infrastructure research presents many challenges due to its inherent heterogeneity,dynamics and multidomain characteristics. GSI,the grid security infrastructure mainly oriented to security authentication and communications,pays insufficient attention to the access control. The traditional access control methods are mainly concerned about the security problems of the provider of resources and miss the protection of the access requesters. The diversity of the operation and user heterogeneous computing environments lead to the dynamic Grid environment and uncertainty.The access control method should be improved when dynamic and uncertain changes of the grid environment affect the access requester. It should be asked to dynamically adapt to the security status changes of the grid environment. In this paper we present a security evaluation model for grid (SEMFG) in order to evaluate the security of the access environment and the requester .Evaluation results can guide the access control.

  An Analysis of the CallCompletion Rates in GSM Network Optimization

  YANG Yun,FENG Ya

  2010, 32(10): 20-22. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 403 )   PDF (627KB) ( 338 )   　　

  Callcompletion rate is an important measure of the quality of the GSM networks.According to the basic theory of GSM network optimization,the paper analyse and studies the phenomenon of the low callcompletion rates,details the factors which affect the rates of GSM network optimization and proposes a set of feasible and effective optimization methods,and thus achieves an improved callcompletion rate,and an optimized  GSM network,and designs the software of  GSM network optimization. Finally,an instance of the GSM network in An Yang where exists low callcompletion rates is discussed,and the optimization software to improve the callcompletion rates is confirmed.

  A Network Traffic Classification Method Based on the MIXKernel SelfOrganizing Maps

  TAO Xiaoling1,HU Ting2

  2010, 32(10): 23-25. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 484 )   PDF (448KB) ( 262 )   　　

  Due to the worse classification performance of classical SelfOrganizing Maps (SOM) for network traffic，a network traffic classification method based on the MIXKernel SelfOrganizing Maps(MIXKSOM) is proposed. Applying a mixed kernel function that is the linear combination of the radial basis function and the polynomial function to replace the Euclidean distance as distance measure, this method can not only combine the advantages of global and local kernel functions, but also simplify the complicated flow sample from the input space to the feature space. The experimental results show that this method has a better performance for classifying network traffic than the classification method based on the traditional SOM and the single kernel function SOM(KSOM), and get a better accuracy rate than NB.

  A LowPowerOriented Mechanism for Shared Cache Partitioning on CMPs

  XIONG Wei，YIN Jianping，SUO Guang，ZHAO Zhiheng

  2010, 32(10): 26-29. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 545 )   PDF (533KB) ( 297 )   　　

  As the development of CMPs,the size of a onchip cache increases and it consumes more and more power of the whole system. How to reduce the power of cache has become a focus of many designers of modern caches. This paper investigates a lowpoweroriented runtime mechanism for shared cache partitioning. A shared cache partitioning framework is proposed,and it uses the Miss Rate Monitors to collect the miss rate information of the current applications at runtime. Then the miss rates are inputted to a lowpoweroriented cache partitioning model to get the partitioning solution within the performance degradation threshold (PDT). Our evaluation,on top of a two core CMP processor with a shared L2 cache,with 21 multiprogram workloads,shows that when PDT is 1% and 3%,the rates of L2 cache shutdown will be up to nearly 20.8% and 36.9% respectively.

  Fabrication Development of the RoomTemperature Single Electron Transistor

  CHI Yaqing,ZHONG Haiqin,SUI Bingcai,ZHANG Chao,FANG Liang

  2010, 32(10): 30-33. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 420 )   PDF (747KB) ( 442 )   　　

  Single electron transistor (SET) is considered as one of the most promising nanoelectronic devices for its nanoscale dimension and ultralow power consumption. Roomtemperature operation and the precise controllability of the device structure are the key issues for the widespread use of SET. The dominant fabrication techniques of the roomtemperature single electron transistor (RTSET) are the topdown process and the bottomup process. The topdown process is convenient for the integration of SETs,but difficult to control the error of the nanostructures and the characteristics of  SETs; the bottomup process is easy to make SET operate at room temperature,but also hard to reduce the error of the coupling structures in SETs. The next key to study is bring new nanostructure fabrication methods to improve the precision of the SET process based on both the topdown and bottomup processes.

  The FPGA Implementation of LargeScale QR Decomposition

  ZHOU Jie1,CHEN Xiaoyang1,ZHAO Jianxun2,DOU Yong1

  2010, 32(10): 34-37. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 495 )   PDF (686KB) ( 370 )   　　

  Largescale QR decomposition is widely used in many fields,such as signal processing,large image processing,and computational structure dynamics,and so on. Traditional methods adopt  parallel computers to accelerate  largescale QR decomposition,which is a computationintensive algorithm. This paper presents a finegrained parallel implementation of Givens Rotation QR decomposition on FPGA. A scalable linear array of processing elements (PEs),which is the core component of our hardware design,is proposed to implement this algorithm. To our knowledge,this is the first  FPGAbased implementation of largescale QR decomposition. A total of 15 GRPEs can be integrated into an Altera StratixII EP2S130F1020C5 FPGA.The experimental results show that a speedup up to 19 can be achieved relative to the Pentium Dual CPU.

  A Survey of the FaultTolerance Techniques for LargeScale Parallel Computing Systems

  FU Hongyi,YANG Xuejun

  2010, 32(10): 38-43. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 349 )   PDF (552KB) ( 687 )   　　

  Fault tolerance is critical to computer systems. Recently,as the ever increasing complexity of architecture and the development of semiconductor techniques,the density of chips becomes much higher. As a consequence,the reliability issue of computer systems emerges,not only for largescale parallel systems,but also for distributed environments,even desktop applications. This paper reviews a number of typical faulttolerance techniques concerning hardware faults proposed in recent years,especially for those designed for largescale parallel systems,draws some preliminary conclusions,and puts forward several potential  research topics of this domain.

  Metrics of Measuring Parallel Computing Systems

  WANG Zhiyuan,YANG Xuejun

  2010, 32(10): 44-48. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 361 )   PDF (420KB) ( 505 )   　　

  The research of metrics for evaluating parallel computing systems is important to parallel systems and application design. First,based on an analysis of the current metric models for parallel computing systems,this paper classifies these model into two categories including the single computing performance model and the synthetically multiple factors productivity model. The work which has been done in the field is reviewed. Then,the various metrics are described. Something that is missing in the current research and the factors which should be considered in building the metric model are pointed out. Since the measure index for the performance of the systems demands a shift from “high performance” to “high productivity”,the paper takes the reliability and energy consumption into account,builds the reliability parallel speedup and energy parallel speedup model in view of scalability,and further proposes a metric model for evaluating the productivity of parallel computing systems. Finally,the direction of further research is proposed.

  An Improved Map Matching Algorithm and Its Application in the Inspection System of Mobile Communications

  ZOU Beiji,HE Jiabei,RUAN Peng

  2010, 32(10): 49-53. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 456 )   PDF (763KB) ( 506 )   　　

  The inspection system is a morden method for dynamic management and quantification of personnel and equipment. Considering the inspection system of mobile communications,his paper proposes an improved map matching algorithm based on the shortest path. Based on the fact that the GPS data is collected with irregular and relatively long sample intervals ,this algorithm not only finishes map matching but also determines the routes between two successive points. Finally,this algorithm is applied in the inspection system of Changsha Mobile.

  Design and Implementation of a LongRange arget Localization and Collimation System

  SU Longfei,HU Dewen,ZHOU Zongtan，ZHANG Huan

  2010, 32(10): 54-58. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 533 )   PDF (845KB) ( 341 )   　　

  A longrange targets automatic localization and collimation system which takes the human face as the anchor point has been developed. In order to improve the performance,the skintone detector and the face detector based on AdaBoost are used in our system. First,the skintone detector checks the available video to separate the skin area from others,then the skintone area is processed with the AdaBoost face detection method to implement realtime localization and collimation. According to the experience,for the front faces and the faces with small angles,the system has a good result. Within the distance of 300m,it localizes and collimates the targets precisely and satisfies realtime requirement. The system is able to reduce the complexity and increase the precision of localization and collimation,and is suitable for the front line of a battle and saving hostages and so on.

  A New Embedded Wavelet ImageCoding Algorithm

  LEI Meimei,YU Liang

  2010, 32(10): 59-62. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 432 )   PDF (478KB) ( 367 )   　　

  A new embedded wavelet image coding scheme is proposed to improve the efficiency of EZW which was founded by Shapiro: divide subbands into important ones and unimportant ones. To avoid the repetitive scans,it is necessary to scan only the important subbands,which will decrease the number of zerotrees needed to scan and code. Besides,the resorting of the subordinate list,which pays a lot but little benefits is given up. Experiments show the simple algorithm saves code streams,speeds up the coding and decoding course,and increases the efficiency without losing the precision of coding. Moreover,we analyse and study some improved algorithms put forward recently,and compare the algorithm in this paper with them.

  ThreeDimensional Landform Data with TextureInformation Lossless Hiding Technique

  LIU Xuchong1,2,WANG Jianxing1,HU Huaping3,LUO Yong4

  2010, 32(10): 63-65. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 431 )   PDF (750KB) ( 258 )   　　

  In this paper,the information hiding technology is used in protecting the 3D landform data. The information of elevation is hidden in the texture. Keeping the terrain figure and hypsography,the terrain information is compressed in low bit ratio. The landform data are embedded into the texture data by an improved histogram shift. The texture data can recover losslessly after the data are restored. The hidden DEM data can not be detected easily,and the data can not be drawn restored by the illegal user without the key.

  An Improved Image Coding Schemefor NonNegative Sparse Coding

  CHAO Yongguo

  2010, 32(10): 66-68. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 394 )   PDF (513KB) ( 410 )   　　

  In the long process of human evolution and development,every day,the human visual system deals with a lot of visual information. For its own survival and development,the human beings have to evolve a powerful imageprocessing capability,such as image coding of the visual system,etc. Sparse coding successfully simulats the strong ability of image coding of the primary visual cortex in mammals’ visual systems such as human,which features selfadaptability,and the learned image base are localized,oriented in space domain and bandpass in the frequency domain. Nonnegative sparse coding developes and evolves on the basis of sparse coding,to overcome the interoffset phenomena of characteristics,and the coding performance is more superior. And the nonnegative sparse coding,which joins the  image structure information using the experience modality decomposition technology,reflects the structural characteristics of the image better in addition to ensuring the characteristics of nonnegative sparse coding. An image coding approach based on the image base is presented in this paper,and the improved nonnegative sparse coding algorithm is used in image compression,and an ideal compression ratio in ensuring a better quality of the decoded images is achieved.

  A Structural Analysis Approach to  OnlineHandwritten Mathematical Expression

  LU Xiaowei,LIN Jiayu

  2010, 32(10): 69-72. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 369 )   PDF (649KB) ( 884 )   　　

  This paper is based on an online handwritten mathematical expression recognition system. In this paper,we propose a structural analysis approach for mathematical expressions based on the partitioned tree transformation approaches. The approach firstly divides the mathematical expression into several subexpressions ,according to its internal structural information . Then,with a tree transformation it displays the spatial relations of all the characters of each subexpression. In this algorithm,the spatial relation types are greatly simplified,and the algorithm can deal with the expression with a nested structure .Moreover,it can be easily enhanced to suit for different kinds of applications.

  Research on  a Parallel Best Neighborhood MatchingAlgorithm for High Definition Image Restoration

  ZHANG Yanyan,HE Liqiang

  2010, 32(10): 73-76. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 498 )   PDF (614KB) ( 333 )   　　

  The Best Neighborhood Matching (BNM) algorithm is an error concealment algorithm to achieve high quality image restoration. Due to the high computation cost,BNM can not meet the realtime processing requirement at this time. In this paper,we extend the original BNM algorithm which only considers the grey scale images to color images,and use a parallel BNM algorithm for high definition images. Our experiment is done in a fournode Linux cluster system. The results show that the speedup of our parallel algorithm is 7.52 when the damage rate of the image is 15%. It improves the efficiency of BNM,and does not reduce the restoration quality.

  Research of the Tracing Interpretation of the ThreeDimensional Interactive Layers of Seismic Data

  ZHENG Xiaoyue

  2010, 32(10): 77-79. doi: 10.3969/j.issn.1007130X.2010.

  Abstract ( 394 )   PDF (563KB) ( 313 )   　　

  Layer interpretation is some kind of analysis and processing of seismic data. Aided by the result,geological characteristics can be dynamically shown intuitively. Now,it is an important technology in the process of geological and resource exploration. The effect of interpretation affects the efficiency and success of followup directly. Traditional interpretation methods have lots of drawbacks because of its 2D interpretation approaches based on 3D seismic data,such as low utilization rate of information and rough accuracy.Two new threedimensional interactive layers interpretation methods of profile guidance and data volume guidance are introduced in the paper which compensate for the deficiencies of traditional methods from different aspects. The principle and advantages are analyzed,and at the same time the implementation algorithms and effect pictures are given.