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• 2011, No. 9　Published:25 September 2011 Last issue    Next issue
  Columns in this issue: 论文

• 论文

  Research on Scalable IPTV Data Transport Quality Monitoring in Tree Topology Access Networks

  YANG Liu1,SUN Zhigang2,TANG Zhuo1,LI Renfa1

  2011, 33(9): 1-6. doi:

  Abstract ( 392 )   PDF (562KB) ( 411 )   　　

  IPTV data transport quality monitoring is one of the most important technologies that must be studied for the deployment of this application. According to the access network with tree topology, this paper proposes a new method for transport quality monitoring based on perhop delay variation detection. With the realtime and continuous attributes of IPTV streams, this method can be used to measure the output port queue lengths and congestion points in a switch. Our analysis shows that this method is scalable and easy to be deployed in the network.

  Modeling the Uncertain Data in the KAnonymity Privacy Protection Model

  WU Jiawei,LIU Guohua,WANG Mei

  2011, 33(9): 7-12. doi:

  Abstract ( 519 )   PDF (438KB) ( 317 )   　　

  Modeling is the basis for the data management of uncertainty. The specificity in the uncertainty of the data in the kanonymity privacy protection model is found, namely, its uncertainty is caused by artificial generalization, and the probability that each instance is reduced after generalization to the original tuple is equal. Because of its specificity, the past modeling approaches of uncertainty data are not suitable for the uncertainty data in the kanonymity privacy protection model simply. In order to describe uncertainty data in the kanonymity privacy protection model, several new modeling methods are proposed in this paper: the Kattr model uses the attributeors ways to describe the uncertainty in the quasiidentifier attribute values of the kanonymity privacy protection model; the Ktuple model takes the quasiidentifier attribute values as relations and use the  tupleors ways to describe the relations; the Kupperlower model separates some generalization values to two fields: the upper limit and the lower limit; the Ktree model based on the property that kanonymous table is the generalization of the ordinary relation with generalization tree splits the quasiidentifier attribute value into a certain tree reversely. A model space which consists of these models is given. The completeness and closure about these models are discussed later.

  A Network Intrusion Detection Algorithm Based on Relative Distance Competitive Activation

  LIANG Bizhen,LU Yueran,YANG Xuguang

  2011, 33(9): 13-18. doi:

  Abstract ( 395 )   PDF (446KB) ( 368 )   　　

  Aiming at the problem of lower efficiency of network intrusion detection learning algorithms at present, a concept called relative distance is proposed in this paper, and then competitive activation and similarity measurement are constructed based on it. On that basis we put forward an improved network intrusion detection algorithm. The advantage of the improved algorithm is: (1) The relative distance can distinguish the terms of column with a large range very well and realize normalization in a lower complexity; (2) Competitive activation of relative distance can process the data which includes the characteristics in a lower computation complexity without converting characters into integers; (3)The algorithm needs no reset. Examination results on the KDD Cup99 sets show that the improved algorithm can reduce the learning time and the testing time significantly while maintaining the accuracy of detection compared to other approaches.

  A Heuristic Algorithm for the QoS Problem Based on MultiConstraints

  XIONG Lijun1,XIE Zheng2,CHEN Zhi2,ZHANG Jun3

  2011, 33(9): 19-23. doi:

  Abstract ( 399 )   PDF (449KB) ( 328 )   　　

  On the communication network, QoSbased routing has become the hot technique in order to fulfill the requirements of multimedia communications. Generally, finding a path in the network that satisfies multiple independent constraints is known to be NPcomplete. In this paper, we discuss the multiconstrained path (MCP) problem. By transforming the problem to discrete dynamic networks, which is acyclic, we propose a more efficient heuristic algorithm for QoS routing. The running time complexity is reduced from O(Tmn) to O(Tm), where m is the number of edges and n is the number of nodes, T is an integer defined by the algorithm. Further more, we theoretically prove the correctness of the algorithm. In the end, some experimental results are presented to show that the proposed algorithm performs better than other algorithms when used to solve the MCP problem. This improved heuristic algorithm can also be used in largescale networks.

  Research on User’s Rights Control Technology Based on Authentication Trustworthiness

  WEI Lifeng,DING Yan,CHEN Songzheng,HE Lianyue

  2011, 33(9): 24-28. doi:

  Abstract ( 443 )   PDF (452KB) ( 324 )   　　

  Authentication trustworthiness reflects the degree of trustworthiness of the user who has passed system authentication. Based on authentication trustworthiness, logging in  is restricted, user’s role and role’s mandatory access control rights are restricted, and then the user’s rights control technology is proposed. Combing authentication trustworthiness with accessing systems, it requests that the user must have some authentication trustworthiness when he wants to access a system, and the important user must pass an important identity authentication mechanism. Applying authentication trustworthiness to RBA(Role Based Authorization), it can decide which role can be activated by the user, and also can decide what rights can be activated by the active role of the user, and reflects on every mandatory access control policy, it implements the unification of authentication and access authorization, solves the problem of improper right obtaining. Finally, more contents to be studied are pointed out.

  Multithreaded Encryption and Decryption Technologies of HyperChaos Cipher

  LIU Shuo1，XUAN Lei2

  2011, 33(9): 29-33. doi:

  Abstract ( 430 )   PDF (539KB) ( 276 )   　　

  Aiming at the defects of virtual machine antivirus technologies, a hiding algorithm of malicious code based on multithreaded hyperchaos cipher encryption is proposed by combining hyperchaos Hénon mapping with multithreaded synchronization. Hiddenness factors of malicious code are  analyzed, and a hiddenness analysis model of malicious code is proposed based on AHP.Gray pigeon malicious code is  used to test and analyze the hiding algorithm of malicious code, and then the hiddenness analysis model of malicious code is used to analyze the experimental results. The results demonstrate the effectiveness of the malicious code hiding algorithm. The research in this paper increases the hiddenness and threat of malicious code, and it provides a new way for antivirus technologies.

  Ensemble Learning and Active Learning Based Personal Spam Email Filtering

  LIU Wuying,WANG Ting

  2011, 33(9): 34-41. doi:

  Abstract ( 455 )   PDF (785KB) ( 348 )   　　

  This paper proposes a personal spam email filtering method, which can learn a user’s interests and update it automatically according to the user’s feedback. The proposed method extracts the linguistic features and behavior ones to build some rulebased individual filters, and uses the SVM ensemble learning method to combine the multifilter’s results. Applying an active learning method to choose those knowledgeable emails with the user’s labels, the method can minimize the number of labeled emails and reach steadystate performance more quickly. The experimental results show the personal filtering method based on ensemble learning and active learning can capture personality, and achieve high performance with the considerations on accuracy, efficiency and learning ability.

  Code Performance Optimization and Analysis Based on Itaniuam Microprocessors

  CHI Lihua,LIU Jie

  2011, 33(9): 42-47. doi:

  Abstract ( 355 )   PDF (454KB) ( 318 )   　　

  High performance computing is widely used in science and engineering to solve large scale computation problems. But the sustained performances achieved for the real applications do not increase as fast as the peak performances do. In fact， the sustained performance is a only about 5~10% of the peak performance, and the gap between the sustained performance and the peak performance is widening. Code performance optimization, which is one of the effective ways to solve this problem, draws the attentions of the research community. Based on Itanium microprocessors, this paper summarizes the general methods for code performance optimization and gives the common steps for code performance optimization and analysis. According to the steps, the performances for four codes are analysed in detail to find the performance bottlenecks and the key subroutine codes. Then four codes are optimized in the Itanium microprocesspor, using the code optimization techniques based on cache and instruction pipeline. Finally, the test results for the four performance optimization codes show that the performances are increased by 8~33% respectively.

  Technology,Changsha,Hunan 410073,P.R.China Gossip Algorithm in Chord Like Network

  LIU Dehui1,2,YIN Gang1,WANG Huimin1,ZOU Peng1

  2011, 33(9): 48-51. doi:

  Abstract ( 475 )   PDF (431KB) ( 341 )   　　

  In this paper, we study the applicability of the Gossip algorithm in the Chord networks. We propose ModGossip, an improved push & pull style Gossip algorithm according to the characteristics of Chord. The simulation results show that the push & pull style Gossip algorithm can be applied in the Chord networks, and the rounds needed to spread the information of one node to the whole network in the Chord networks is approximately the same as that in a fully connected network. However, ModGossip can save about 2 rounds. In dynamic networks, the joining of nodes will not influence the execution of the push & pull style Gossip algorithm and ModGossip.

  A New Design of the Hypervisor Logical Domain Channel

  FENG Hua,TANG Hongwei,LU Kai

  2011, 33(9): 52-56. doi:

  Abstract ( 414 )   PDF (555KB) ( 332 )   　　

  The UltraSparc T1/T2 processor provides virtualization support.Its platform firmware Hypervisor acts as the virtual machine manager. The logical domain channel is a software mechanism that supports the domaintodomain and domaintohypervisor communication. The logical domain channel is a simple implementation  lacking flexibility.Besides,the communication based on the logical domain channel needs data copying so as to heavily decrease the performance of data transfer.This paper introduces a new technique of logical domain channel. It directly transfers data from one side to the other side based on data descriptors and needs no copying.On the other hand,the size of the transferred data will not be limited by the buffer size of the logical domain channel.The new technique implements a more flexible and quick data transfer between virtual machines.

  An Efficient Algorithm of Hardware/Software Partitioning and Scheduling on MPSoC

  HAN Honglei,LIU Wenju,WU Jigang,LI Hui

  2011, 33(9): 57-62. doi:

  Abstract ( 454 )   PDF (586KB) ( 320 )   　　

  Hardware/software (HW/SW) partitioning and task scheduling are the crucial steps of HW/SW codesign. It is very difficult to achieve the optimal solution as both scheduling and partitioning are combinatorial optimization problems. In this paper a heuristic solution is proposed for scheduling and partitioning on the multiprocessor system on chips (MPSOC). In order to minimize the overall execution time, the proposed algorithm assigns different priorities to different tasks according to their outdegree and the software execution time. The higher the outdegree, the higher the priority. For the tasks with the same outdegree, the higher the software execution time, the higher the priority. The proposed algorithm initially searches for the critical path in the task graph, and then assigns the task with the highest benefittoarea ratio to hardware implementation. The critical path and the available hardware area are updated during the iteration. The whole calculation process works until the available hardware area is not enough to implement any software task in the critical path. As a result, the hardware area is utilized as many as possible. Simulation results show that, the proposed algorithm can reduce the overall execution time up to by 38% in comparison to the latest work.

  A Calculation Model for the Evolution of Unconventional Emergencies

  CHEN Lei1,CHEN Shihong1,2,LIU Yu2,WANG Yunhua2

  2011, 33(9): 63-69. doi:

  Abstract ( 403 )   PDF (564KB) ( 343 )   　　

  Disturbance, high complexity and derivatives are main features which are different from normal emergencies of unconventional emergencies. In response to these characteristics, studying the evolution model of unconventional emergencies to control the complexity and development trend of event handling process has become a hot research problem. In this paper, the authors propose the NFA (Nondeterministic Finite Automation) evolution model and the corresponding evolutionary algorithms of unconventional emergencies, the evolution rules in the form of description, and the event handling scheme selection and resource scheduling functions. Examples show that the NFA model can describe not only the evolution of events, but also the relationships between handling process, scheme selection and resource scheduling. Compared with other existing models, its computability is the most important feature.

  Computation Tree Logic Based on Possibility Measure

  XUE Yan1，LEI Hongxuan2，LI Yongming1

  2011, 33(9): 70-75. doi:

  Abstract ( 391 )   PDF (491KB) ( 363 )   　　

  Firstly, the definition of possibilistic Kripke structure is presented, and the possibility measure space based on it is established. The properties of possibilistic Kripke structure are discussesd, such as the possibility of each path is the infimum of the initial distribution and all of the transisiton possibilities, and the possibility measure which is defined in accordance with the possibilistic Kripke structure is reasonable, etc. Secondly, the possibility computation tree logic (PoCTL) is defined, the equivalence between two PoCTL formulae is studied, and the problems whether some PoCTL formulae are equivalent to some CTL formulae are analyzed. Finally, the persistence property corresponding to PoCTL in CTL*are proved.

  A Verification Method for Web Services Combination Based on Abstract and Refinement Techniques

  CHEN Guobin1,REN Qiang2,ZHANG Guangquan2,3

  2011, 33(9): 76-80. doi:

  Abstract ( 447 )   PDF (544KB) ( 269 )   　　

  Model checking has been widely used to verify the compatibility of Web services composition models, since it can give counterexamples and high automation. As for the state explosion problem existing in model checking, we introduce the predicate abstraction and refinement techniques into the traditional model checking method, and propose a framework for Web services composition based on the such techniques. First, we model each Web service based on the predicate abstraction and composite the models with combination operations. Second, we project the counterexamples obtained by model checking over each Web service, and confirm the projection counterexamples. Third, the Web service abstraction model that causes spurious counterexamples is refined, and a new composition abstract model, whose properties also should be verified, is generated. Finally, we show the correctness of our proposal to relieve state explosion.

  Property Testing of Binary Relations and Its Complexity Analysis〖

  WEI Li，XU Daoyun

  2011, 33(9): 81-87. doi:

  Abstract ( 395 )   PDF (442KB) ( 293 )   　　

  The basic principle of property testing is introduced, the possibility of using property testing methods to solve parameterized problems is analyzed, and then the isomorphism properties are parameterized. It studies the property testing of binary relations and parameterized framework isomorphism properties. For a fixed distance parameter, it proves that the testing complexity is better than the complexity of exact decision procedures for every property studied.

  Differential Evolution Algorithm for MultiObjective Optimization

  AO Youyun1，CHI Hongqin2

  2011, 33(9): 88-94. doi:

  Abstract ( 423 )   PDF (600KB) ( 304 )   　　

  Fitness assignment of individuals and diversity maintenance of population are two key techniques of evolutionary algorithms. First, on the one hand, this paper introduces some related concepts of Pareto εdominance which can determine the strength Pareto values of the individuals of population, according to the strength Pareto values of individuals, some better individuals are selected into the offspring population by the technique of Pareto ranking; on the other hand, in order to maintain the diversity of population, a crowdeddensity method is introduced to remove some individuals that are located in the crowed regions. Then, according to some characteristics of differential evolution (DE), through using the appropriate DE strategies and control parameters, this paper proposes a differential evolution algorithm for multiobjective optimization, which is called DEAMO. Finally, numerical experiments show that DEAMO can perform well when tested on several benchmark multiobjective optimization problems.

  An Improved Particle Swarm Optimization Algorithm Based on New Mutation Operators

  2011, 33(9): 95-99. doi:

  Abstract ( 403 )   PDF (637KB) ( 383 )   　　

  Particle swarm optimization (PSO) is an optimization algorithm based on swarm intelligence.Based on introducing PSO’s theory and flow, this paper analyzes the phenomenon that it suffers from premature convergence, longer search time and lower precision when dealing with complex problems. An improved particle swarm optimization algorithm based on new mutation operators(NMPSO) is presented.The mutation operator is compared with the current particles, and the better one will be selected. So the diversity of population is improved, which can help the algorithm avoid premature convergence efficiently. The comparative simulation results on five benchmark functions verify that NMPSO improves PSO’s global search capability, convergence rate and precision.

  Research on Network Path Planning Algorithms Based on MultiAnt Colonies’ Parallel Optimization

  HUANG Zehan1,2,TAN Yuejin1 

  2011, 33(9): 100-104. doi:

  Abstract ( 345 )   PDF (440KB) ( 427 )   　　

  The traffic manager needs to plan a scheme for each mission in military support or emergency, which is a multisource multidestination problem. It is NPC. A new network path planning algorithm based on multiant colonies’ parallel optimization is presented. According to a certain scheduling policy for key network resources, finding a feasible path which satisfies the constraint of transportation properties and the constraint of service quality for each support task, and a scheme which makes the morest missions be successful is planned. Finally, an example is used to validate the model and algorithms.

  An Efficient  Mining Algorithm of Temporal Association Rules

  LI Guangyuan1,2,LIU Yinghua1,3,LIU Yongbin1

  2011, 33(9): 105-108. doi:

  Abstract ( 387 )   PDF (458KB) ( 345 )   　　

  Temporal association rules mining(TARM) is widely applied in many applications, it aims at mining rules within a certain interval of time. Most of the exiting algorithms for TARM need to scan several times of the database, or do not consider the different exhibition period of an individual item, so the efficiency of these algorithms are not enough. In this paper, we present a novel approach to investigating TARM, the proposed algorithm works in an incremental way which takes the different exhibition period of individual item into account, in order to reduce the cost of storage, and only the frequent 1item is stored, and efficient pruning techniques are adopted to reduce the scan times of the database, and it only needs at most one time to scan the whole data set to obtain all the temporal association rules. The  experimental results show that the proposed algorithm is efficient.

  An Index Based on Basic Information Units

  LIU Li,Gou Yanyan,WU Yangyang

  2011, 33(9): 117-122. doi:

  Abstract ( 315 )   PDF (933KB) ( 295 )   　　

  Information retrieval is an important function which data spaces must provide. This paper describes an index for an information retrieval subsystem of a data space system. Using the relationship between the data in the data space, the relevant data are extracted to compose some basic information units, and then an extended inverted lists based on the basic information units is created for multi_source heterogeneous data. The experiments show that using the index based on basic information units, the system can return comparatively complete semantic information.