05 October 2007, Volume 33 Issue 19
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Computer Engineering. 2007, 33(19): 1-3,25. https://doi.org/10.3969/j.issn.1000-3428.2007.19.001Taking difficulty on exact measurement and complete expression of NGI (next generation Internet) network status into account, this paper presents a flexible QoS multicast routing algorithm based on DE (differential evolution) with introduction of fuzzy mathematics. the corresponding model and its mathematical description are introduced. Under inaccurate network status information and flexible user QoS requirement, the proposed algorithm tries to find the multicast tree with the maximum confidence degree on meeting with user QoS requirement and the user satisfaction degree on the achieved QoS. Simulation results have shown that the proposed algorithm is both feasible and effective.
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Computer Engineering. 2007, 33(19): 4-6,28. https://doi.org/10.3969/j.issn.1000-3428.2007.19.002Automatic evaluation of fingerprint image quality is an important step in automatic fingerprint identification system. According to the requirement in real application of fingerprint identification system, an automatic quality evaluation algorithm of fingerprint images is proposed. The method integrally evaluates the quality of captured fingerprint images in several respects, such as fingerprint foreground area, pressing position of finger, gray-level variation of fingerprint image, orientation consistency and clarity degree of ridge-valley structure. The algorithm can accurately prompt the user for different kinds of bad quality fingerprint images in the process of fingerprint capture, and can also mark the region of bad quality to ensure reliability of fingerprint feature matching. The experimental results prove the method effective.
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Computer Engineering. 2007, 33(19): 7-9. https://doi.org/10.3969/j.issn.1000-3428.2007.19.003This paper proposes an universal logic control model based on zero-order universal combination model of universal logic, and designs the structures from 1 to 4 dimensional universal logic controllers according to the number of inpnt. Because of referring to the general correlation between the input values, the controller has strong generality and adaptability. For different controlled objects, the universal logic control model doesn’t need to be designed specially. It is an intelligent control model with flexible talent. The control experiments for classical linear and nonlinear systems prove the validity and advantage of universal logic control model.
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Computer Engineering. 2007, 33(19): 10-12,3. https://doi.org/10.3969/j.issn.1000-3428.2007.19.004Due to the promising mobility in IEEE802.16e, MS (mobile subscriber) is tightly constrained by battery capacity. So sleep mode mechanism becomes an important component for MS which can effectively manage the limited energy, and prolongs the use time of once-charged battery. This paper reviews 3 types of power saving classes of sleep mode of MS in IEEE802.16e, investigates the combinations of several power saving classes, and solves the problems of energy consumption and energy saving of MS at sleep mode. By system model simulation, it presents the methods of performance evaluation and enhancement of sleep mode based on variable parameter configurations.
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Computer Engineering. 2007, 33(19): 13-15. https://doi.org/10.3969/j.issn.1000-3428.2007.19.005This paper introduces the structure of intrusion detection system in mobile Ad Hoc networks, and analyzes a model of layered weighted IDS and clustering algorithm. According to the hierarchical structure, it gives a scheme of broadcasting and transferring alert message using digital signature. It designs the packet format of alert message, and gives the source code of ELFhash Hashing function.
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Computer Engineering. 2007, 33(19): 16-18,4. https://doi.org/10.3969/j.issn.1000-3428.2007.19.006This paper considers gross interference power of each reception nodes in Ad Hoc networks. It establishes a probability model for successful reception and modifies the protocol-interference model for Ad Hoc networks. By the method of probability, a quantity analysis of simultaneous transmission performance is obtained. The numeric results show the impacts of different network parameters, which include signal loss exponent and ratio of transmission and interference radius upon available simultaneous transmission capacity.
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Computer Engineering. 2007, 33(19): 19-22,4. https://doi.org/10.3969/j.issn.1000-3428.2007.19.007
It is necessary to guarantee the validity of Web services and their composition. Since B-method is a model-based formal method, which has strong structuring mechanisms and good tool support, it is an effective method for modeling and verifying. Therefore, this paper models for Web Services and their composition and verifys the B model with the help of the tools of B.
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Computer Engineering. 2007, 33(19): 23-25. https://doi.org/10.3969/j.issn.1000-3428.2007.19.008There are usually lots of heterogeneous storage nodes in the virtual network storage system. Methods of data assignment on homogeneous storage system do not adapt to heterogeneous system any more. A new self-adaptability method (AD) of data assignment on virtual network storage system is proposed. It can obtain the optimal data assignment and efficiently utilize both the I/O bandwidth and storage capacity of all storage nodes. Experimental results show that this method can fully utilize the heterogeneous storage nodes’ performance, resolve the imbalance problem of data placement of grid storage system, and increase the utility ratio of the virtual network storage system effectively.
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Computer Engineering. 2007, 33(19): 26-28. https://doi.org/10.3969/j.issn.1000-3428.2007.19.009It is difficult to apply the current P2P network service to the business fields without QoS guarantee. This paper introduces QoS attributes into the P2P network and proposes a service composition model, gives a computing method of service composition, proposes an improved genetic algorithm, and provides the solving procedure to satisfy the customer’s service level agreement. A set of experiments show that the proposed model and algorithms can achieve better performance.
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Computer Engineering. 2007, 33(19): 29-32. https://doi.org/10.3969/j.issn.1000-3428.2007.19.010Situation evaluation is an important part of the decision support system. Because the strategy of confrontation is the essence of SimuroSot, situation evaluation of the robot and ball on the ground is a necessary and effective way to enhance strength of the team. This paper presents and analyses the mathematical model based on situation evaluation of the robot and ball on the SimuroSot5vs5 platform, and puts forward an effective and practical procedures algorithm, whose validity is tested out in experiments and matches.
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Computer Engineering. 2007, 33(19): 33-35，3. https://doi.org/10.3969/j.issn.1000-3428.2007.19.011In order to enrich the cognitive ability of artificial fish in virtual marine environment, this paper proposes a memory-based cognitive model of artificial fish according to the biological principle and memory mechanism of natural fish. Information is transferred and stored during the three stages: ultra short-term memory(USTM), short-term memory(STM) and long-term memory(LTM). Artificial fish uses the focuser to extract the interested sensory information, and uses the decision-maker and STM to select behaviors and stores the experience knowledge to LTM which is called by STM to optimize current decision-making. Animation results show that artificial fish with this model can have memory-directed behaviors and display more vivid and intelligent life properties.
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Computer Engineering. 2007, 33(19): 36-38. https://doi.org/10.3969/j.issn.1000-3428.2007.19.012This paper studies distributed planning techniques based on contract net for dynamic tasks scheduling of multiple unmanned aerial vehicles (UAVs) in battlefield, presents a multi-UAV tasks scheduling model, develops and a distributed tasks scheduling architecture is developed. A novel path planning algorithm based on probabilistic road maps is designed, which can plan predictive routes between the UAV and multiple tasks rapidly. Contract net protocols are expanded to simultaneity deal with multiple trades in one auction, so that negotiation efficiency is improved. By integreting several contract types which can work together, tasks scheduling in complex battlefield situations is solved.
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Computer Engineering. 2007, 33(19): 39-41. https://doi.org/10.3969/j.issn.1000-3428.2007.19.013Relations between bit error rate (BER) and average received signal-to-noise ratio(SNR) in AWGN channel are derived for π/4-DQPSK and 8DPSK modulations modes in Bluetooth 2.0+EDR specification. Function expressions of packet broadcasting retransmission probability and average received SNR of ACL data packets are put forward. The adaptive packet selection policy is presented for the Bluetooth 2.0+EDR specification packets in different SNRs, which selects proper packet in different SNRs to get the least retransmission times and the maximal broadcasting throughput. Simulation results can be used to achieve a good broadcast performance in different channel conditions.
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Computer Engineering. 2007, 33(19): 42-44. https://doi.org/10.3969/j.issn.1000-3428.2007.19.014Based on the useful, true, timely and reasonable software metrics, this paper builds the project resource model during CMMI performance. When plenty of resources data are collected during the improvement of organization’s level of capability maturity, based on the resource model of completed projects, projects resources data can be incorporated and organization resource model can be built by using the equivalent class partition technique based on clustering. Correct resource model can be used to plan, predict, monitor and control project resources quantitatively and efficiently.
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Computer Engineering. 2007, 33(19): 45-46. https://doi.org/10.3969/j.issn.1000-3428.2007.19.015This paper researches on equivalence problem of security protocol and presents the notion of security protocol equivalence. Messages and goals of each security protocol are formalized with different set of expression, then most general substitute of the set of expression can be solved by an algorithm. If there exists most general substitute, security protocols are equivalent, or security protocols are not equivalent. According to the equivalence relation on the set of security protocol, equivalence class of security protocol is divided, so amount of researching security protocol is decreased.
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Computer Engineering. 2007, 33(19): 47-48,5. https://doi.org/10.3969/j.issn.1000-3428.2007.19.016This paper analyses fuzzy support vector regression, presents a new fuzzy support vector regression method based on time series analysis (TS-FSVR), and optimizes parameters of model by particle swarm optimization (PSO). This method is successfully used to the evaluation system of tour-environment carrying capacity. The experimental results show the method is feasible.
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Computer Engineering. 2007, 33(19): 49-50,5. https://doi.org/10.3969/j.issn.1000-3428.2007.19.017This paper psoposes a method of reconstructing curved surface from two images. Two images are photographed from the frontal and lateral direction of the curved object. Then the silhouettes of the two images are obtained by user-interaction. And the smoothest 3D surface which projects exactly to these silhouettes can be recovered by minimizing the linearly constrained quadratic object function. In addition, surface creases are realized by adding a parameter to the quadratic object function. The promising reconstructing results validate the effectiveness of this method.
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Computer Engineering. 2007, 33(19): 51-53. https://doi.org/10.3969/j.issn.1000-3428.2007.19.018Polyglot is a highly extensible compiler frontend framework, while avoiding code duplication. Users may extend the framework to define any necessary changes on abstract syntax tree and semantic analysis for implementing language extensions. In order to direct users to work with Polyglot fleetly, the main flow and class hierarchy of Polyglot are summarized, and the methodologies of the scalable extensibility are anatomized, in which the delegation, visitors and abstract factories are employed. And the use steps of Polyglot and the related application are stated in a nut shell.
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Computer Engineering. 2007, 33(19): 54-56. https://doi.org/10.3969/j.issn.1000-3428.2007.19.019This paper presents that data creating system is an important method in computer audit data processing, analyzes the function and principle of the system, implements it by using Visual Basic 6.0 tool, and introduces application of it in computer audit data processing. Results show that data creating system avoids the shortages of actual data, and creates the necessary test data, which is helpful to research data processing method.
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Computer Engineering. 2007, 33(19): 57-59. https://doi.org/10.3969/j.issn.1000-3428.2007.19.020Priority inversion is the most common problem occurring in real-time system when using a real-time kernel. In order to solve the problem, the operation system must dynamically hoist the task priority which occupies the resource. This paper analyses the task scheduling principle of μC/OS-II, and then proposes a method based on the priority inheritance and hoist, which solves the problem. It improves the task scheduling of the real-time system and strengthens its real-time performance for the high-priority task.
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Computer Engineering. 2007, 33(19): 60-62,6. https://doi.org/10.3969/j.issn.1000-3428.2007.19.021This paper separates requirements of open distributed system into functional requirement, monitoring requirement and manipulating requirement, mapping the system as a coordination layer and a function layer. Based on Java information service and EJB technology, it proposes an infrastructure implementation. Experimental results of vehicle navigation system show the module’s interactivity and real-time interaction.
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Computer Engineering. 2007, 33(19): 63-65. https://doi.org/10.3969/j.issn.1000-3428.2007.19.022Through the research on classification of the association rules mining, this paper presents a definition method about association rules mining. According to the correlation between the items, it proposes an algorithm APAR based on ANN-PCA, and consequently the application of the association rules mining is extended. Experimental results show the algorithm is effective.
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Computer Engineering. 2007, 33(19): 66-68,7. https://doi.org/10.3969/j.issn.1000-3428.2007.19.023This paper focuses on the research of multi-level association rules mining, and presents a fast algorithm FAMML_FPT on frequent pattern tree. This algorithm can realize data mining not only among an identical level association rule but also among cross-level association rules. In this algorithm, conceptions of the repaired items and the cross-level repaired items are brought, which is propitious to create FP-tree from lower levels to higher levels. This algorithm can reduce the scanning times of the database and eliminate the need for generating the candidate items, which improves efficiency of data mining.
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Computer Engineering. 2007, 33(19): 69-71. https://doi.org/10.3969/j.issn.1000-3428.2007.19.024Based on existed models, this paper proposes a new one that can reduce checking times of the original database, and points out problems in IncSpan+ and defects in interpret mining based on semi-frequent patterns. It constructs a prefix tree to represent the sequence patterns, and continuously maintains the tree structure by using width pruning and depth pruning. Experimental results show the algorithm has a good performance.
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Computer Engineering. 2007, 33(19): 72-74,8. https://doi.org/10.3969/j.issn.1000-3428.2007.19.025Traditional P2P model can not give attention to both searching efficiency and dynamic nature, thus, problems, such as single point-invalidation and load-disproportion exist. This paper presents a new P2P model, topic-based structured P2P network (TS-P2P), which inosculates the merit of unstructured and structured P2P model, adopts multilateral hash to insert peers and publish database resources. Based on cache buffer and distance, it chooses best peer to communicate by comparing PRI. This model improves the capability of P2P networks on searching speed, veracity, single point-invalidation, and load-disproportion.
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Computer Engineering. 2007, 33(19): 75-78. https://doi.org/10.3969/j.issn.1000-3428.2007.19.026Establishing and improving software process capability is the requirement of the high maturity level of CMM or CMMI, and also a difficult problem of software measurement. This paper discusses the related concepts and issues of software process capability, defines the software process capability indexes, and gives the quantitative solution to establish and improve software process capability by using XmR control chart technique of statistical process control. An example of establishing and improving software process capability is given to illustrate the usage of the quantitative solution.
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Computer Engineering. 2007, 33(19): 79-81. https://doi.org/10.3969/j.issn.1000-3428.2007.19.027This paper presents a component-based framework of mobile robot. This framework can reduce the complexity in application building, and improve code reuse. By developing a uniform control and network platform and establishing a group of abstract class and interface, the framework component can be dynamically loaded and linked. By changing component, the robot can be flexibly adjusted to work under different control manners and network control modes. An example illustrates how Java and XML techniques are used in the frame.
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Computer Engineering. 2007, 33(19): 82-84. https://doi.org/10.3969/j.issn.1000-3428.2007.19.028In order to detect boundary points of clusters effectively, a technique making use of objects’ density and distribution feature in its Eps-neighborhood to detect boundary points, and a boundary points detecting algorithm named BOUND(detecting boundary points of clusters in noisy dataset) is developed. Experimental results show that BOUND can detect boundary points in noisy dataset containing different shapes and sizes clusters effectively and efficiently.
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Computer Engineering. 2007, 33(19): 85-87. https://doi.org/10.3969/j.issn.1000-3428.2007.19.029This paper introduces a kind of XML based markup language: message queuing markup language(MQML), which could be used to describe e-business, e-government and enterprise integration. MQML is extendables, with flexible structure and can explain itself. It also can be deployed and used in existing application with the help of XML. An application instance is given to describe the value of MQML for e-government.
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Computer Engineering. 2007, 33(19): 88-90,9. https://doi.org/10.3969/j.issn.1000-3428.2007.19.030This paper introdues a new kind of scalable distributed data structure—EP*. An EP* file can scale up to many servers and its structure is simple. EP* structure supports single-record operation and range query operation. Experiment shows that as compared to EH*, EP* not only adds range query functon, but also has more stable load factor and message cost for single-record operation during file’s growing up.
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Computer Engineering. 2007, 33(19): 91-92,1. https://doi.org/10.3969/j.issn.1000-3428.2007.19.031A software test process management platform named QESuite2.0 is designed. This paper summarizes the related models in GJB 2725A-2001 and its accessories. Based on these models, general function architecture and framework oriented design scheme of the platform are presented which make the platform support to customize its workflow, function abilities and project item lists. It also supports documents automative generation. Key techniques used in the system implementation is discussed.
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Computer Engineering. 2007, 33(19): 93-95. https://doi.org/10.3969/j.issn.1000-3428.2007.19.032Spatial topological relationships have impacts on spatial query and spatial analysis. This paper analyzes the current methods of describing topological relationships for spatial objects and proposes a novel method, which is based on topological data model, to discover the topological consistency for spatial objects. The mechanism is to define variation ratio by finding topological mode relations among objects, according to the mechanism, topology consistent rules used to check and maintain spatial consistency in the systems can be acquired. As a result, it also can improve the qualities of spatial query and analysis.
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Computer Engineering. 2007, 33(19): 96-98,1. https://doi.org/10.3969/j.issn.1000-3428.2007.19.033This paper designs a new signaling protocol based on FC for embedded safety critical network, and the protocol realizes differentiated service in the queue scheduling according to different data types. Based on this protocol, it discusses how to extend NS2, especially how to build a simulation model by extending frame, node, Agent and link. The simulation results indicate that queue scheduling algorithms work well in differentiated service. Extending NS2 to verify network protocol and algorithms can raise efficiency and reduce costs, on the other hand, it is much more flexible.
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Computer Engineering. 2007, 33(19): 99-100. https://doi.org/10.3969/j.issn.1000-3428.2007.19.034Security and privacy are the crucial conditions in the seal-auction design. For an anonymous bid, a new electron auction is presented based on Hash chain with constructing a Hash chain, root of the chain and Hash value of the random number submitted to the auctioneer by only one time. The scheme differs from the previous electronic auction of secret sharing of the multi-computation protocol that multi-proxy of auction share the identities of the bidders. Its efficiency is distinctly improved in computation and communication.
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Computer Engineering. 2007, 33(19): 101-103. https://doi.org/10.3969/j.issn.1000-3428.2007.19.035This paper puts forward a new mobile grid model supporting offline computing, which breaks through the pattern of traditional service-oriented grid architecture. It presents the components of the model and their relations, and introduces how to deal with the tasks. Following the maneuver of the registered letter, the model realizes high agility.
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Computer Engineering. 2007, 33(19): 104-105,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.036Protocol conformance test of DHCPv6 is to verify whether the implementation conforms to the requirements of DHCPv6’s specification. This paper introduces DHCPv6, analyzes the disadvantages of TAHI’s test, then presents a test topology using virtual testers and a layered message definition structure. On the basis, 61 test cases are designed, then the test experiment against Cisco’s router 2600 is performed and the test result is delivered.
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Computer Engineering. 2007, 33(19): 106-108. https://doi.org/10.3969/j.issn.1000-3428.2007.19.037To solve the problem of the current real-time polling service (rtPS) scheme for MPEG video transmission via wireless MAN, an efficient medium access control (MAC) uplink scheduling algorithm is presented. Without periodical bandwidth request by the base station (BS), the algorithm allocates a constant part of the bandwidth for certain fraction of the MPEG video data when the application connection is set up, and the transmission bandwidth for the remaining fraction is allocated on demand according to the piggyback request of the unsolicited grant data, thus to guarantee better quality of service (QoS). By using typical test video traces in simulation, the algorithm shows better performance in the aspects of video frame delay and jitter with similar channel utilization as the existing scheme.
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Computer Engineering. 2007, 33(19): 109-111. https://doi.org/10.3969/j.issn.1000-3428.2007.19.038Web services reliable messaging offers the reliable method to exchange information between Web services, transforms information into packets, insures successful exchange of data by combining acknowledge, exclusive tag and information of source and destination. The paper introduces the application of WSRM to data exchange in video grid system, explains the disadvantages of WSRM.
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Computer Engineering. 2007, 33(19): 112-114,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.039Based on the analysis of centralized WLAN network structure, in order to effectively decrease the cost of access point equipment and balance the function distribution, the paper puts forward the Split-MAC scheme and introduces the realization method. It introduces each module function of the system framework, describes system initialize flow, process flow of data frame and administration frame of scheme execution. The scheme adapts to real-time application and large-scale deployment of netwok.
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Computer Engineering. 2007, 33(19): 115-118. https://doi.org/10.3969/j.issn.1000-3428.2007.19.040This paper proposes an efficient on-chip communication architecture design method (called CA-CIG) based on CIG. Analysing the communication between processing elements given in CIG, and taking into consideration of the communication cost from the transformation between incompatible protocols and the different bus width, CA-CIG presents a fast and effective architecture prototype design method, and integrates the communication topology generation, bus width configuration and the communication protocol selection processes. To automate the design, CA-CIG also provides the related algorithms for the key steps. This paper uses the JPEG decoder application to demonstrate the effectiveness of the method.
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Computer Engineering. 2007, 33(19): 119-121. https://doi.org/10.3969/j.issn.1000-3428.2007.19.041This paper analyses the problem of the research pattern followed by the existing bluetooth scatternet formation algorithms. A method is proposed that scatternet should be constructed based on the actual capabilities of devices. The method helps algorithms to distribute appropriate roles according to their capabilities. Such idea combines algorithms with applications firmly and improves algorithms’ rationalities and feasibilities. The method is used to improve existing BTCP Algorithm. The analysis proves the method greatly improves the rationality of scatternet construction and stability of the scatternet.
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Computer Engineering. 2007, 33(19): 122-124. https://doi.org/10.3969/j.issn.1000-3428.2007.19.042The Chord, a type of structured P2P routing protocol proposed by MIT base on the distributed Hash table(DHT) technology, has the advantages of entire distribution, balanced load, high scalability & availability, and flexible naming. This paper analyzes the Chord protocol and realizes the basic routing system JavaChord with the Java remote method invocation(RMI) technology. Tests are done for validation.
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Computer Engineering. 2007, 33(19): 125-127. https://doi.org/10.3969/j.issn.1000-3428.2007.19.043NFS is a predominant distributed file system in the cluster. Besides network bandwidth and storage bandwidth, there are some other factors affecting NFS bandwidth as well. With a new MPI-based parallel I/O benchmark Mpbonnie, this paper measures and analyses NFS performance with different configurations in the cluster. It proves server side file system, I/O mode and server side processor have great impact on NFS performance.
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Computer Engineering. 2007, 33(19): 128-129,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.044This paper reviews the basic content of key management. It introduces RSA public key cryptosystems and homomorphic encryption scheme in the integer ring. The homomorphism key agreement based on RSA and homomorphic encryption scheme is presented. The protocol can use the public key of RSA to create the contributory, forward secrecy the session key. Compared with Diffie-Hellman protocol and key agreement protocol based on password, it has separately quicker operation speed and better security. The security of the protocol is proved by BAN logic.
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Computer Engineering. 2007, 33(19): 130-131,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.045A certified E-mail protocol is about fair exchange of a message m for its receipt. Fairness is the most important property in exchange. It modifies existing convertible authenticated encryption scheme so that it can be used by certified E-mail protocols, and based on the scheme, a new certified E-mail protocol is proposed to guarantee privacy and low computation overhead.
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Computer Engineering. 2007, 33(19): 132-133,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.046In wanelet transformation domain, there are lots of semblances among wanelet coefficients at the same direction subbands and spatial location, but different resolutions. This paper proposes an algorithm of robust image watermark based on DWT direction tree structure. The algorithm establishes the model by using support vector machine, hides watermark by adjusting the relation between output and target value of the model. The watermark recovery does not require the original image. Experimental results show that the algorithm possesses good robustness for common image attack, and has lager capacity, better invisibility, better security and super performance.
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Computer Engineering. 2007, 33(19): 134-137. https://doi.org/10.3969/j.issn.1000-3428.2007.19.047The article surveys the state of the privacy and authentication schemes for Ad Hoc networks, analyzes the important problems in establishing and implementing privacy and authentication schemes according to characteristic of Ad Hoc networks, introduces all schemes in existence and makes a contrastive analysis of their merits and faults, proposes some scenarios to solve problems that still exist in these schemes and presents the challenges that are still worth to further research in the area.
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Computer Engineering. 2007, 33(19): 138-139. https://doi.org/10.3969/j.issn.1000-3428.2007.19.048This paper gives some conjectures on the autocorrelation values of new generalized cyclotomic sequences of order 2 of length pq defined by Ding and Helleseth. The results show that the autocorrelation functions of these sequences are 5-, 4- or 3-valued. These sequences have good autocorrelation property. The conjectures come from a computer programm which compute the autocorrelation values. All tested examples confirme to these conjectured values and so these assumptions appear to be well founded. However, a theoretical confirmation is not yet forthcoming. These sequences also have large linear complexity, which make it possible as key stream in stream ciphers or as random number generators.
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Computer Engineering. 2007, 33(19): 140-142. https://doi.org/10.3969/j.issn.1000-3428.2007.19.049Traditional system architectures based on general purpose processor and ASIC can not satisfy requirements to high performance and flexibility of network information audit system. Taking IXP2400 for example, this paper researches the system architecture of network information audit system based on network processor, provides its implementation method and related key technologies. By using interface card ENP-2611 of Radisys company, its implements the proposed system, researches the high efficiency Chinese-English multi-pattern matching algorithm based on network processor. The experiment shows that the speed of proposed system is about 500Mb/s, which is higher than existing systems.
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Computer Engineering. 2007, 33(19): 143-146. https://doi.org/10.3969/j.issn.1000-3428.2007.19.050Computer network security vulnerability assessment is a research focus in network security field. This paper puts forward the research target of computer network vulnerability assessment and the major problems appeared in the course of research. It analyses some resent research methods and techniques aimed at computer network vulnerability assessment, such as network vulnerability assessment in terms of network connectivity, intrusion path, graph theory, analysis tools, agent, AHP, as well as vulnerability dependence relation graph. Based on the analysis, it points out the advantage and disadvantage of each method.
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Computer Engineering. 2007, 33(19): 147-149. https://doi.org/10.3969/j.issn.1000-3428.2007.19.051This paper analyzes the 4 factors that determine which model should be chosen with the method of set: the quantity of users, the radix of function set, the change of role’s permissions, the change of user’s roles. It partitions the different conditions that are suitable for RBAC(role-based access control) model or FBAC(function-based access control) model. This paper demonstrates that it is necessary and feasible to adopt different models in complex large system. In this kind of system, it can deal with two methods: cut apart and combine the permissions; use the mechanism of multistage assignment.
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Computer Engineering. 2007, 33(19): 150-151,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.052This paper proposes a new defense mechanism of DDoS attack based on source-end detection. This mechanism can precisely identify the DDoS data flow and effectively defend the DDoS attack. And it will not impose great negative effect on the network performance and discomfort user’s experience about the normal applications on network. It discusses how to implement this mechanism on Microsoft Windows. It analyzes the statistics gathered in the test.
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Computer Engineering. 2007, 33(19): 152-154,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.053Efficient key management is a difficult task in secure multicast. This paper proposes a new identity-based key agreement scheme for multicast groups based on the works of Wang et al. The procedures of secret communications between subgroups and updating of group keys with the dynamic change of group members are analyzed. The analysis shows that the scheme satisfies the security requirements of key agreement and is efficient in computation and communication.
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Computer Engineering. 2007, 33(19): 155-157. https://doi.org/10.3969/j.issn.1000-3428.2007.19.054Shannon put forward the concept of perfect secrecy and proved that some kinds of cryptosystems are perfect secrecy. The paper analyzes Shannon’s proof of some kinds of cryptosystems about perfect secrecy and points out that Bayes’ theorem was used mistakenly in proof because of mixing up the probabilities under different conditions. An example is given to show that one-time system isn’t perfect secrecy and this leads to a foundation for further study of cryptosystem’s secrecy. The paper educes the new direction of probability and discusses the problems of eclectic calculation probability under several conditions.
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Computer Engineering. 2007, 33(19): 158-160,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.055Aiming at protecting regions consisting of most information or regions of interest (ROI) selected by users in the image, this paper proposes a 2-dimension watermark algorithm for the arbitrarily shaped object based on normalized shape-adaptive DCT, which can embed a gray image’s watermark to an arbitrarily shaped object in the cover-image. It achieves efficient watermark’s extraction and restoration. Experimental results show that this scheme is robust to common signal processing procedures with property of invisibility.
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Computer Engineering. 2007, 33(19): 161-163. https://doi.org/10.3969/j.issn.1000-3428.2007.19.056All the present network forensic systems assume that the system is still working on reliable state when intrusion occurs, and the effect of system state changes is not considered. This paper proposes a network forensic system with intrusion tolerance ability, INFS. Mechanisms and modules of this prototype system are presented, such as intrusion tolerance, forensic control based on SMP, security transition, forensic agent, attack trace agent and so on. This paper discusses different forensic analysis methods corresponding to different states, and brings forward the concept of cooperating forensic.
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Computer Engineering. 2007, 33(19): 164-167. https://doi.org/10.3969/j.issn.1000-3428.2007.19.057This paper analyzes the composite chaotic pseudo-random sequence encryption algorithm(CCPRSEA). By analyzing the linear congruent algorithm on a prime field of CCPRSEA, it gains chaotic sequence and gives a tally-degree-based divide-and-conquer attack algorithm by using the information leak of the chaotic map itself. When base=10 and m=3, it proves that the success rate of the attack algorithm is 0.982 7 and the complexity is 240. Experimental results indicate that it just needs 8 hours and 35 minutes for attacking all keys of CCPRSEA in 2.5GHz of Pentium 4 PC. So CCPRSEA is insecure.
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Computer Engineering. 2007, 33(19): 168-169,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.058Besides importance of data transmittal and database security illustrated, the requisite analysis of the model of teledata access based on CA authentication are elaborated as well. The model is divided into client authentication modules, SQL resolution modules, and data transmittal modules and so on. The model functioned with confidentiality, integrity, identity authentication etc, provide secure and reliable channel for sensitive data between two communication terminals; On the other hand, sensitive data in server database is encoded by fields, which keep invisibility for non-correlation persons. The model, to some extent, can keep sensitive data safe in most enterprises.
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Computer Engineering. 2007, 33(19): 170-172. https://doi.org/10.3969/j.issn.1000-3428.2007.19.059This paper focuses on the privacy preserving sequential patterns mining in the following situation: (1)multiple parties; (2)each has a private data set; (3) wish to collaboratively discover sequential patterns on the union of the multiple private data sets without disclosing their private data to each other. It puts forward a novel approach to discover privacy-preserving sequential patterns based on secure multi-party computation by using commutative encryption and homomorphic encryption technology.
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Computer Engineering. 2007, 33(19): 173-174,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.060Algorithms based on image features are very popular and widely used in image matching. However, the feature extraction process is often sensitive to noises. This paper presents an image matching algorithm using critical feature points in space-scale, which represent image gray-level feature. The algorithm is robust to the illumination intensity and noises. For the purpose of comparing distance between weighted feature points, the proportional transportation distance is used. Because PTD obeys the triangle inequality, the algorithm is suitable for efficient object retrieval and recognition in large database. Experiment result confirms the efficiency.
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Computer Engineering. 2007, 33(19): 175-176,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.061It is very important to locate core point accurately and reliably for classification and matching of fingerprints. This paper presents a novel hybrid method based on modified orientation field estimation and improved complex filtering technique to solve the problem of traditional orientation field algorithm. The experiment results show that the proposed algorithm is effective and robust.
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Computer Engineering. 2007, 33(19): 177-179. https://doi.org/10.3969/j.issn.1000-3428.2007.19.062This paper presents an image semantic description in high-level information. In order to explain and calculate the image semantics, the feature vectors and the semantic partition are constructed in structure related. And also the selection of vector space is discussed. In the vector space, an idea is given for the selection of minimum vector dimensions which is being proved by discriminant. From the vectors selection, the structure of feature projection and the formulation can effective to calculate the data from low-level to high-level in image retrieval and recognition. The principles and the experiments show the thoughts can help others in semantic retrieving.
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Computer Engineering. 2007, 33(19): 180-182. https://doi.org/10.3969/j.issn.1000-3428.2007.19.063HSV histogram is a commonly used, effective method for shot boundary detection. This paper deals with computing discontinuity values based on shape and color content in image frames. Then Kohonen self-organized network is used to differentiate boundaries from frames. Experimental results show that this method can avoid wrong and omited detection as a result of adopting single characteristic, and Kohonen net can perform as well as slide window Gaussian’s model method, while diminish the influence of the parameters on the detection performance.
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Computer Engineering. 2007, 33(19): 183-185. https://doi.org/10.3969/j.issn.1000-3428.2007.19.064Aimed at the deficiency of universal thresholding denoising, this paper nitoroduees a new subband-adaptive denoising algorithm based on weighted threshold. After analyzing statistics of wavelet coefficient for wavelet denoising of natural image, an exponentially decaying inter-scale model for image wavelet coefficients is suggested for the adaptation of the denoising filter across scales. Then a subband-adaptive thresholding algorithm is proposed based on statistics comparison of noisy image and original one, which avoids unbalanced denoising cross scales. Experiments show that higher peak-signal-to-noise ratio and better subjective visual effect can be obtained as compared to other thresholding-denoising algorithms.
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Computer Engineering. 2007, 33(19): 186-187,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.065
Support vector machine algorithm becomes another important technique after neural networks in the field of machine learning, but the evaluation and choice for kernel function is not solved. Based on the structural risk theory, a quantity estimation is proposed though empirical risk and confidence interval, and an evaluation formula for kernel function is given. This article points out the default of traditional definition of empirical risk, and gives a new definition. The results of simulation experiment show the feasibility and effectiveness of the method.
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Computer Engineering. 2007, 33(19): 188-189,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.066The segmentation of lung parenchyma is the foundation of chest CT image processing, such as lung nodule detection, quantitative analysis of lung function, three-dimensional reconstruction, and visualization analysis. This paper uses an edge detection method based on genetic algorithm to segment the lung parenchyma of original chest CT image. With global searching capacity and the largest variance between clusters as the fitness function, this method can search the optimal threshold of edge detection automatically, and extract the edge of lung parenchyma by combining morphologic processing to realize the segmentation of lung parenchyma. Experiment shows that the method can not only simplify the segmentation of lung parenchyma, but also achieve a good segmentation effect. It has a good foreground in application.
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Computer Engineering. 2007, 33(19): 190-192. https://doi.org/10.3969/j.issn.1000-3428.2007.19.067As many research papers appear on the Internet, it is very important to accurately extract paper header information and citation from these papers. Thispaper proposes an algorithm based on hidden Markov model for extracting paper header information and citation from Chinese research papers, analyzes the key to the learning of the module structure and method of parameter estimation. In the processing, the algorithm makes full use of the format information of list separators and special-labels to segment text, and gains extraction information of special-fields, based on hidden Morkov model. Experimental results show that the algorithm has good performance in precision and recall.
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Computer Engineering. 2007, 33(19): 193-195. https://doi.org/10.3969/j.issn.1000-3428.2007.19.068This paper proposes a novel multi-focus image fusion method based on point spread functions (PSF). It uses Gaussian functions to convolve with multi-focused images repeatedly. Compared with approximation error images, it gets the focus and defocus regions, and segments the regions through morphological method. It uses choose-max fusion rules to get the all-in-focus image. Experimental results show that the image is distinctly segmented into multi-regions, the image edge is legible, and the fusion results are satisfactory.
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Computer Engineering. 2007, 33(19): 196-198. https://doi.org/10.3969/j.issn.1000-3428.2007.19.069This paper proposes a novel simulated annealing algorithm based on the immune programming——IPSA, after analyzing the advantages and disadvantages of the simulated annealing algorithm. With analogies to the concept and theory of biological immunity, the algorithm combines the global optimal capability of the immune programming with the local optimal capability of simulated annealing algorithm, overcomes inefficient speed of simulated annealing algorithm. Theory analysis and experimental results show that the algorithm keeps population diversity, and increases convergent speed and stability greatly. The proportion of converging to the global optimization can reach 91%.
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Computer Engineering. 2007, 33(19): 199-200,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.070The quality assessment of images is meaningful for most video and images applications. The structure similarity index(SSIM) shows some defects when evaluating the quality of blur images and noise images, the results don’t match the HVS system well. This paper proposes a new image quality assessment algorithm based on dual-scale edge structure similarity(MDESSIM). The edge information is appreciated sufficiently during the structure information in this algorithm. The distortion metric of edge structure is included in the assessment of the image quality. Experimental results demonstrate the MDESSIM algorithm is effective.
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Computer Engineering. 2007, 33(19): 201-203. https://doi.org/10.3969/j.issn.1000-3428.2007.19.071This paper presents an improved politics for premature to provide a mechanism for resuming population diversity. Population diversity is kept by keeping schema diversity. The means is regenerating schema that lose or less in population. To scale degree of validity, schema regenerate excepted value is introduced. An improved politic is analyzed by used schema regenerate excepted value, and examples show that the method is effective.
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Computer Engineering. 2007, 33(19): 204-206. https://doi.org/10.3969/j.issn.1000-3428.2007.19.072Microarray data has the feature of high dimensions and small samples, which causes difficultis to the analysis. Therefore, it is important to select or discover informative genes from microarray data. This paper presents an informative genes selecting method based on genetic algorithm (GA), in which k nearest neighbors (KNN) is implied as a recognition method. Support vector machine (SVM) is used to construct a tumor classifier system and different kernel functions are used to test the performances. This method has been applied to a classic microarray data set (leukemia data) and achieved 100% classification accuracy on the test data set.
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Computer Engineering. 2007, 33(19): 207-209,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.073This paper proposes a set of local line pattern detector(LLPD) for automatic rail detection in freight railway stations. It uses LLPD to extract the features of rail edges, and discards the fallacious patterns from the result of the previous step. It re-connects the broken lines using Hough transform. Compared with other edge detection methods, the new technique is efficient for rail detection with complex surrounding. The proposed method can locate the obstructions on the railroads and thus of great importance for reducing railroad accidents.
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Computer Engineering. 2007, 33(19): 210-212. https://doi.org/10.3969/j.issn.1000-3428.2007.19.074Behavior model of air-attack stream adopts frame structure of Agent and the measure of synthesize CBR and RBR technology, resolves the representation and proceedings of Air-attack field knowledge. To perfect the responses behavior model, this paper puts forward the operation rules of indeterminacy based on inter-zone number, conflict resolution and search strategy. The air-attack model indicates the advantages of behavior modeling, and creates air-attack stream to represent intelligence and simulate actual responses of air pilots perfectly.
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Computer Engineering. 2007, 33(19): 213-214. https://doi.org/10.3969/j.issn.1000-3428.2007.19.075Clone selection and better diversity of immune learning is introduced into particle swarm optimization algorithm to construct an algorithm immune particle swarm optimization algorithm(IPSO). The modified algorithm can avoid the local optimization and has better performance for multi-peak function optimization problem. The algorithm is applied to four familiar test functions. Experimental results illustrate that the IPSO has the potential to achieve better and faster convergence.
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Computer Engineering. 2007, 33(19): 215-217,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.076Synchronization is a difficulty in performance testing. Previous tests use round-trip delay to avoid the synchronization problem, but the jitter error can not be neglected. So precise testing one-way delay is very important. The paper provides a way, using round-trip delay to compute one-way delay, through transmitting and accepting delay. Based on this method, it tests a real multimedia network.
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Computer Engineering. 2007, 33(19): 218-220. https://doi.org/10.3969/j.issn.1000-3428.2007.19.077This paper explores how to construct dynamic multi-resolution models for terrain elevation data by using multi-resolution characteristic of wavelet transform and proposes a wavelet-progressive-reconstruction algorithm to solve the problem of smooth transition between multi- resolution models. It also solves crack problem between terrain blocks of different resolution through a simple “sewing” method. Experiment result illustrates that this method can realize view-dependent continuous rapid rendering of large-scale terrain.
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Computer Engineering. 2007, 33(19): 221-223. https://doi.org/10.3969/j.issn.1000-3428.2007.19.078n order to improve the precision of the 3D motion capture system based on CCD devices using software and decrease the space-warp error arisen from CCD imaging and assembling, this paper compares several data-fitting methods and proposes a layered and repetitious data-fitting algorithm based on searching by analyzing scattered data fitting theory. The algorithm is explained and the experiment results are presented. Experiments show that its accuracy, time complexity and convergence are better than other approaches. It is a practical data-fitting algorithm and is appropriate for calibrating the motion capture data.
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Computer Engineering. 2007, 33(19): 224-226. https://doi.org/10.3969/j.issn.1000-3428.2007.19.079According to the demand of multi-channel high-speed data acquisition and real-time control of the experiment model of pulse detonation engine(PDE), this paper designs and realizes a real-time measurement and control system based on virtual instrument technology. The hardware and software architecture system is introduced. The key techniques including anti-jamming technique, multi-thread programming and card control technology based on register are mentioned. Applications in practice indicate that it owns high real-time performance and dependability and it meets the needs of high-speed data acquisition and control time.
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Computer Engineering. 2007, 33(19): 227-229. https://doi.org/10.3969/j.issn.1000-3428.2007.19.080This paper proposes a modified multiple-word radix-2k Montgomery multiplication (MWR2kMM) algorithm with its corresponding VLSI architecture. With the adoption of MWR2kMM algorithm, the proposed multiplier is able to work with any precision of the input operands and has a shorter critical path. Meanwhile, its performance is much higher compared with previous work because of the optimization of the pipeline architecture. The proposed multiplier is very suitable to the low cost and high performance RSA cryptosystem and can be easily implemented in VLSI technology.
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Computer Engineering. 2007, 33(19): 230-232,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.081With the development of modern industry, the requirements of power distribution system is increasing, which is based on many technologies such as modern electron technology, sensor technology, communication technology, computer and network technology. In a word, intelligent power distribution system has already become a development trend. So a kind of design of DC power distribution box based on CAN/LIN bus is put forward. CAN bus is used to connect the master computer and DC power distribution boxes, and the LIN bus is used to connect the DC power distribution box and low speed switches. The design not only can perform the control function, but also can reduce the cost. It is a practical design.
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Computer Engineering. 2007, 33(19): 233-235,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.082After analyzing the requirement of management and control system of AS/RS(automated storage/retrieval system), the difference between the system and the SCADA(supervisory control and data acquisition) system which is used in process control, is pointed out. And the hierarchical function structure of the system is also illustrated. Combining the advantages of Ethernet and field-bus, the network architecture fit to applied in AS/RS is proposed, which takes the switched Ethernet as its upper levels net, and takes field-bus as its lower levels net. And the Ethernet-based communication model used between the supervisor computer and the PLC is presented. The realization and utilization of the design are described. The information and software integration of the system are illuminated, too. The design has lower cost and achieves system integration of management and control of an AS/RS by common devices and technology.
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Computer Engineering. 2007, 33(19): 236-237,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.083This paper analyzes 2 critical problems in FPGA-based implementation of SOM neural network algorithm: parallelizability and finite word-length effect. The analysis of the two problems, this paper presents a highly parallel architecture to implement this algorithm and shows the circuit of critical blocks. By the result of computer simulation and FPGA implementation, shows that the architecture can ensure the quality of the neural network and meanwhile make the circuit have a high computing speed.
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Computer Engineering. 2007, 33(19): 238-240. https://doi.org/10.3969/j.issn.1000-3428.2007.19.084The wireless sensor network(WSN) is a research hotspot in the communication realm. This paper introduces the theory and factual circuit design of wireless communication system of WSN based on MSP430F1611 and TR3000. Furthermore, some important questions in design are discussed. The experimental result shows that the wireless communication system satisfies the demands of small and low power comsumption.
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Computer Engineering. 2007, 33(19): 241-242,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.085Based on the discussion about advantage of object-relation mapping(ORM) this paper introduces the architecture of ORB based on Nhibernate, gives the procedure of using NHibernate in the information system of airport, and analyzes several key factors which influence the efficiency of using ORM.
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Computer Engineering. 2007, 33(19): 243-245. https://doi.org/10.3969/j.issn.1000-3428.2007.19.086Knowledge organization and classification is important for an intelligent searching system. A metadata model for the intelligence searching of vegetable supply chain knowledge is proposed based on investigation. The model contains the knowledge of vegetable supply chain knowledge database, the domain concepts and user classification. It integrates them as a whole. The metadata model is the base of knowledge sharing and reusing for vegetable supply chain. It formalizes the model by OWL and implements the intelligent searching system.
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Computer Engineering. 2007, 33(19): 246-248. https://doi.org/10.3969/j.issn.1000-3428.2007.19.087In traditional implementation of IPTV networking architecture, ADSL and other Wireline technology is the typical solution for “last mile” in access network. This paper analyzes the network requirement of IPTV and WIMAX technology on theory, researches the feasibility of WIMAX technology as the access network solution of IPTV.
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Computer Engineering. 2007, 33(19): 249-250,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.088The particle system is a successful methods for simulating anomalous and fuzzy object. Concerning the real-time characteristic, the meaning express and the simply operation of the digital high-definition title generator this paper presents the method such as texture mapping, particle movement control, color inquire to improve the tradition algorithm of particle system. According to the result of experiment, the improved algorithm enriches the title generation of the digital high-definition title generator, obtains perfect image effect.
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Computer Engineering. 2007, 33(19): 251-252,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.089Chip multithreading (CMT) represents the direction for future high-performance processors, and simulation is an integral part of the processor architecture research and design process. This paper presents the design and implementation of a SimpleScalar-based cycle-level simulator—OpenSimCMT, which serves for designing and evaluating the CMT architectures. OpenSimCMT features that: (1) supporting the simulation of simultaneous multithreading (SMT) as well as chip multiprocessors (CMP); (2) open framework and well configurable, being extendible to accommodate a given research goal, and readily to append new simulation contents and relative statistic; (3) all-around simulation, supporting inter-thread resource sharing and competition, various function units, pipeline, branch prediction, multi-level caches, etc, facilitating accurate simulation.
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Computer Engineering. 2007, 33(19): 253-255. https://doi.org/10.3969/j.issn.1000-3428.2007.19.090The electronic seal becomes more and more important in the domain of E-government and E-commerce, and the solution for electric seal based on digital signature and digital watermark is still in developing. Following the Domino-PDF-DSA technique path, this paper synthesizes the technology for PDF digital signature and Lotus platform PKI, successfully makes second-exploiter in virtue of Notes C API and PDF API, extends the Notes ID file with electric seal image, and implements an application system which embedded electric seal into PDF file on Lotus platform.
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Computer Engineering. 2007, 33(19): 256-258,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.091As the contemporary commercial bank develops in the aspects of the bank transaction and service variety, there are more and more data files used in the bank software R&D center. Therefore, it becomes an urgent issue as to how to centrally backup these data, and how to protect the data and make sure the safe processing to the greatest extent. This paper discusses the approaches and strategies that the bank software R&D center employs to centrally backup all the important data, also with the Veritas Netbackup product, it discusses the detail strategy of how to implement it using Veritas Netbackup product.
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Computer Engineering. 2007, 33(19): 259-261. https://doi.org/10.3969/j.issn.1000-3428.2007.19.092This paper solves real-time curve plotting problem by creating a new plotting data interface which has large expansibility and transplant behavior under an embedded GUI application. This GUI application is applied under the embedded Linux environment based on the PC/104 platform. A new low level plotting mechanism and method is created in order to solve the dynamic scale and glitter scream problem. The experiment result shows that they can solve the real-time plotting problem well under embedded application.
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Computer Engineering. 2007, 33(19): 262-263,. https://doi.org/10.3969/j.issn.1000-3428.2007.19.093Based on inference model, this paper proposes a fundamental structure, knowledge representation, reasoning mechanism in the real-time decision of banana intelligence expert system. The mechanism combines concern rectangle and inference based on the produce type inference, improves accuracy of the system. Experimental results show the system is effective.
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Computer Engineering. 2007, 33(19): 264-266. https://doi.org/10.3969/j.issn.1000-3428.2007.19.094This paper proposes a cheat-detection mechanism based on delta state for P2P MMOG. A player’s delta state in other players’ game views is measured by definite integral. It determines whether the player is cheating or not, according to the delta state and taking network delay in reference. Judgment standard is decided by thresholds. Simulation results show that the cheat-detection mechanism can detect this kind of cheating which will induce state inconsistent between other players effectively, so that security of MMOG is enhanced.
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Computer Engineering. 2007, 33(19): 267-269. https://doi.org/10.3969/j.issn.1000-3428.2007.19.095This paper introduces the characters, the framework and designing methods of data warehouse, and puts forward a practical project for the data warehouse using in the analysis of the charges of curing and being in hospital. And this project is on the basis of Oracle Warehouse Builder and Discoverer used for OLAP analysis. The data warehouse supports the mass data on the further handling and recycling. It also solves some technical problems such as the implementation of the data warehouse, data analysis, and client program designing. The system helps the hospital to make decisions positively.
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Computer Engineering. 2007, 33(19): 270-272. https://doi.org/10.3969/j.issn.1000-3428.2007.19.096By analysing the requirement of data collection, management and release with embedded system, the article explains the principle of data collection through UART and data management and release through embedded active Web. It also discusses how to carry out the system on ARM9+Linux platform.
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Computer Engineering. 2007, 33(19): 273-275. https://doi.org/10.3969/j.issn.1000-3428.2007.19.097Based on the different kinds of data integration methods, this paper brings forward an ontology-and-XML-based data integration framework for eliminating the semantic heterogeneity, including application layer, middleware layer and database layer. It expatiates the pivotal technology of implementation and gives an application instance in the integration information system of aviation equipment.
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Computer Engineering. 2007, 33(19): 276-278. https://doi.org/10.3969/j.issn.1000-3428.2007.19.098This paper presents an approach to eliminate noise based on framework of Web pages and rules. This approach divides a page into several parts according to HTML tag
or
related to paragraph, the noise content is eliminated based on this way. Experiments performed on a set of 132 559 Web pages from CWT200G show that this approach can eliminate noise content of Web pages effectively and decrease the size of index files to about 75%. The information retrieval speed can be faster, and the accuracy of retrieval can be improved.
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Computer Engineering. 2007, 33(19): 279-282. https://doi.org/10.3969/j.issn.1000-3428.2007.19.099City traffic managers and users are troubled by the jam of cross-over Huangpu river traffic. By analyzing spatial distribution feature of the cross-over Huangpu river route way and traffic, this paper advances the notion and general design principle, hardware and software architecture, and presents the method of the ration estimate of the system application. ith advanced and reliable CDMA wireless communication and the GIS for urban public traffic, traffic information guidance system is set up based on B/S framework. The application indicates that the system achieves its expected aim.
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Computer Engineering. 2007, 33(19): 283-封3. https://doi.org/10.3969/j.issn.1000-3428.2007.19.100This paper describes the attributes, essence and importance of extraction transformation loading(ETL) technology by discussing the application in the business information system in waterage passenger transportation industry. It studies how ETL technology is used to solve the problems in data search, modification and maintenance. The use of ETL can separate the database system completely, and decrease the load of data search, increasing the speed of search and analysis.
2024
Volume 50 No 4
Volume 50 No 4
(Started in 1975, Monthly)
Sponsored by：
East-China Institute of Computer Technology Shanghai Computer Society
Edited & Published by：
Editorial Board of Computer Engineering
Chief Editor：Jiang Bo
Executive Chief Editor:
Hu Bing
Tel：021-67092217
E-mail: ecice06@ecict.com.cn
CN: 31-1289/TP
ISSN: 1000-3428
Sponsored by：
East-China Institute of Computer Technology Shanghai Computer Society
Edited & Published by：
Editorial Board of Computer Engineering
Chief Editor：Jiang Bo
Executive Chief Editor:
Hu Bing
Tel：021-67092217
E-mail: ecice06@ecict.com.cn
CN: 31-1289/TP
ISSN: 1000-3428