20 December 2011, Volume 37 Issue 24
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Computer Engineering. 2011, 37(24): 1-3. https://doi.org/10.3969/j.issn.1000-3428.2011.24.001To prevention metamorphism and new malware effectly, a static detection method based on data mining is proposed and its key technique is discussed. Melware code is disassembled and preprocessed into sequential data, an Apriori-like algorithm is used to discover sequential pattern and remove normal pattern, the result pattern set can be used to detect unknown malware. Experimental result shows that the method has high accuracy rate and low false positive rate.
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Computer Engineering. 2011, 37(24): 4-6. https://doi.org/10.3969/j.issn.1000-3428.2011.24.002Most existing integrated unicast and multicast schedule algorithms can not keep high throughput when the ratio of unicast and multicast traffic changes, a dynamic integrated schedule algorithm of unicast and multicast is proposed. The algorithm is designed based on Input Queued(IQ) switch which is used widely. By monitoring the ratio of unicast and multicast traffic of the latest several time slots at the input port, it dynamically decides the integrated schedule scheme of unicast and multicast. Simulation results show that the unicast throughput, multicast throughput and overall throughput of the proposed algorithm are always higher than that of FILM and fSCIA, and the overall average delay of the proposed algorithm is also the best.
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Computer Engineering. 2011, 37(24): 7-9. https://doi.org/10.3969/j.issn.1000-3428.2011.24.003In this paper, a new Non Line of Sight(NLOS) error mitigation algorithm based on Kalman filter and neural network is proposed. According to the features of Time of Arrival(TOA) measurements and the statistic characteristics of NLOS errors, the condition on which can obtain the unbiased estimation of Kalman filter is deduced. It fixes on the state transition matrix of Kalman filter with neural network in different environments. Simulation results show that the location performance of the algorithm is improved with better estimation accuracy and robustness.
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Computer Engineering. 2011, 37(24): 10-12. https://doi.org/10.3969/j.issn.1000-3428.2011.24.004Considering the simplicity of scalar processing and the effectiveness of vector processing when doing color digital image noise reduction, a method of domain replacement is proposed in this paper. It processes the image data in RGB space with mean filtering, converts the image data from RGB to HSI, and replaces the original H and S domain with that filtered. The noise in H and S domain is reduced indirectly after these operations. The method is tested with an actual color image captured from a binocular endoscope. According to the results of the test, the method of domain replacement may have both the advantages of scalar processing and vector processing. Compared with common scalar processing and simple vector processing, the method can achieve a better effect.
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Computer Engineering. 2011, 37(24): 13-15. https://doi.org/10.3969/j.issn.1000-3428.2011.24.005A global point pattern fingerprint matching method based on Genetic Algorithm(GA) is presented. In order to avoid the low efficiency and premature convergence of standard GA, an fast GA is proposed. The algorithm can make the matching process converge rapidly to the global optimal result through narrowing down the population size and the number of best individuals step by step, reducing the probability of mutation, and trying to select individuals with high fitness. Experimental results show that the improved algorithm can enhance the accuracy of fingerprint matching with less time cost.
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Computer Engineering. 2011, 37(24): 16-17. https://doi.org/10.3969/j.issn.1000-3428.2011.24.006The Local Binary Pattern(LBP) method does not consider the contrast value between neighbor pixels, so the feature representation ability of LBP method is limited. According to the problem, this paper proposes a Local Multi-layer Contrast Pattern(LMCP) method to overcome this disadvantage. It limits the illumination variation and divides the contrast value range between neighbor pixels in local area into several layers. Every contrast value is mapped into a certain layer. The statistic histogram for every contrast layer is constructed using the same idea as LBP method. In order to solve the problem of expanded feature dimension, it adopts statistics mapping method to reduce the histogram bins. Experimental result based on Outex_TC_00012 texture database proves that the LMCP method has good classification effect.
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Computer Engineering. 2011, 37(24): 18-21. https://doi.org/10.3969/j.issn.1000-3428.2011.24.007Traditional digital signature schemes need much more storage and management overhead for the use of certificates, while the identity-based digital signature schemes fail to solve the inherent key-escrow problem. Certificateless signature schemes need no certificates and can solve the key-escrow problem. This paper presents a certificateless signature scheme from bilinear pairings, and verifies its security under the random oracle machine. It designs a certificateless group signature scheme from the certificateless signature scheme, and its security is founded under the assumption of the computational Diffie-Hellman problem. Performance analysis shows that both signature schemes are secure and have high performing efficiency.
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Computer Engineering. 2011, 37(24): 22-24. https://doi.org/10.3969/j.issn.1000-3428.2011.24.008The Reverse K Nearest Neighbor(RKNN) problem is a generalization of the reverse nearest neighbor problem which receives increasing attention recently, but high-dimensional RKNN problem is little explored. This paper studies on the high-dimensional main-memory RKNN queries, proposes an indexing structure called Δ-RdKNN-tree, precomputes KNN distances of points in the dataset by main-memory KNN self-join based on this index and propagates these distances to higher level index nodes. Main-memory RKNN query algorithm based on this index is proposed and main-memory RKNN join algorithm is given for set-oriented RKNN queries. Analysis shows that the two algorithms are effective in high dimension space.
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Computer Engineering. 2011, 37(24): 25-27. https://doi.org/10.3969/j.issn.1000-3428.2011.24.009In real application environment, when tree database carries out live updating, the present tree-cluster algorithm can not update existing cluster result. In consideration of the semi-structured characteristics and the lower accuracy rate of similarity measurement of tree, this paper puts forward a similarity measuring method of combining knot semantics and structure feature of one side of knot. On that basis, it brings forth Closed Tree Update Mining (CTUM) algorithm, Tree Cluster(TC) algorithm and Update Tree Cluster(UTC) algorithm, which can separately solve problems of increment updating, clustering and increment clustering of close subtree. Experimental result proves that the novel algorithms are efficient and practicable to own higher executing efficiency and better cluster accuracy rate.
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Computer Engineering. 2011, 37(24): 28-31. https://doi.org/10.3969/j.issn.1000-3428.2011.24.010This paper describes the design and implementation of a framework for XQuery Hotspot compiler system, which obtains more efficient performance by translating the frequently called methods into Java byte code on the basis of online runtime profile information. Experimental results show that the approach offers high performance in comparison with the interpretive system, and provides better method to deal with dynamically generated XQuery program on Internet in comparison with the static compiler system.
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Computer Engineering. 2011, 37(24): 32-35. https://doi.org/10.3969/j.issn.1000-3428.2011.24.011This paper focuses on methods and policies about algorithm recognition, which is turned to recognizing characteristic expression picked up as the distinguishable characteristics, in high-level language that is gained by code reverse analysis. With an eye to the expression in the high-level language recovered, this paper researches methods to recognize algorithm based on abstract syntax tree, and proposes two different policies, which are strict compatibility and anamorphic compatibility, to recognize characteristics expression aiming at recognizing algorithm in the target code, which is of great help to code analysis.
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Computer Engineering. 2011, 37(24): 36-37. https://doi.org/10.3969/j.issn.1000-3428.2011.24.012To the demand of a continuous mining frequent itemset in the same transaction database under multiple minimum support degree, this paper proposes frequent itemset mining algorithm based on multiple minimum support degrees. The algorithm uses set theory, leads into model library, converts the transaction database into a model library, and searches model library to obtain frequent itemset. The algorithm reduces the time of frequent itemset mining and improves efficiency of frequent itemset mining. Experimental results show this algorithm is more efficient than Apriori algorithm.
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Computer Engineering. 2011, 37(24): 38-41. https://doi.org/10.3969/j.issn.1000-3428.2011.24.013In order to reduce the user response time of Web service registry center, on the basis of the characteristics of Universal Description Discovery and Integration(UDDI) standard, this paper divides the system into two layer of inter-domain and internal-domain, and establishes cross-domain system. In this system, inter-domain uses subscription-based approach for asynchronous data replication, internal-domain uses dynamic master-slave replication for synchronization data replication. It optimizes the UDDI data structure. The amount of data before and after optimization is analyzed. The system and complete duplicate systems between nodes are compared. Experimental results show that the system can effectively improve the performance of the service registration center.
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Computer Engineering. 2011, 37(24): 42-44. https://doi.org/10.3969/j.issn.1000-3428.2011.24.014Aiming at the problem that word load of meteorological data loading is very heavy, this paper presents a common model of data loading based on the intelligent adapter. eXtensible Markup Language(XML) and Java Architecture for XML Binding(JAXB) are adopted for metadata makeup and input/output in the model, and the scripting language is used to deploy the rules configuration of intelligent adapter. It develops the meteorological data loading system based on the common model. Operation result indicates that the system has highly flexibility and scalability features.
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Computer Engineering. 2011, 37(24): 45-49. https://doi.org/10.3969/j.issn.1000-3428.2011.24.015For the topic clue inspection of dynamic text flow, this paper proposes an inspection algorithm based on semantic relevance model. It calculates the semantic relevance of message text and topic clue, allots message to related topic clue, and adopts the improved algorithm of semantic relevance model to inspect different data sets and topics of different lengths. Experimental results show that this algorithm gives higher F1 value than current algorithms.
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Computer Engineering. 2011, 37(24): 50-51. https://doi.org/10.3969/j.issn.1000-3428.2011.24.016In distributed database systems, controlling usage of data after it had been released to a different control domain from its provider becomes an important security issue. Aiming at this problem, this paper analyses the characteristics of Role-based Access Control model(RBAC) and Usage Control model(UCON), and proposes a novel secure model of distributed database based on usage control technology. It gives the composition and definition by using different access control policies on server-side and client-side. Analysis result shows that this model can be used as an effective solution for usage control enforcement in distributed database systems.
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Computer Engineering. 2011, 37(24): 52-54. https://doi.org/10.3969/j.issn.1000-3428.2011.24.017A new uncertainty measure, such as dominance degree is proposed in ordered objective information systems based on dominance principle, and an explicit theoretical meaning of rough set is given to the dominance degree which can be used to measure the inconsistence of objective information system. The granulation monotonicity of dominance degree is proved, based on which a new measure of attribution importance is designed. An heuristic reduct algorithm in objective information system is provided based on dominance relation. An example illustrates the validity of this algorithm, and results show that the algorithm has the same theoretical foundation with classical reduct algorithm in rough set theory, and it is easily understood. The algorithm provides an important theoretical basis for knowledge discovery in ordered objective information systems.
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Computer Engineering. 2011, 37(24): 55-57. https://doi.org/10.3969/j.issn.1000-3428.2011.24.018In order to ensure the Wave Division Multiplexing(WDM) optical network to achieve fast speed protection and restoration of optical network against single link failure, the parallel algorithm combined with heuristic algorithm of P-cycle configuration is proposed in this paper. The main idea of this algorithm is to find all candidate cycles in network under some limitations and then use multi-process to parallel calculate the Efficiency Ratio(ER) of all P-cycles, select a P-cycle with the maximum efficiency ratio and configure it. Simulation results show that this parallel algorithm is more suitable for large amounts of P-cycles configuration, and the speedup gets better as the number of P-cycles configuration increases.
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Computer Engineering. 2011, 37(24): 58-60. https://doi.org/10.3969/j.issn.1000-3428.2011.24.019Aiming at the shortage of AFDX switch’s Static Priority Un-interrupt Scheduling(SPUS) algorithm in eliminating output random jitter, Virtual Clock(VC) is added to provide legitimate time in packet schedule for ameliorating the algorithm. Packets sending to cascading port enters shaping scheduling before output queue. Shaping scheduling maintains the switch’s certainty and quality of service. Simulation results show that the algorithm after ameliorating can eliminate output random jitter, which beseems to switch’s cascaded port.
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Computer Engineering. 2011, 37(24): 61-63. https://doi.org/10.3969/j.issn.1000-3428.2011.24.020Based on timing analysis of network sessions, this paper puts forward a detection approach of heartbeat packet sequence based on clustering processing. It processes the network data stream with time clustering, expands the cluster collection by periodic features, and screens out the clusters which do not meet the characteristics, and detects the heartbeat packet sequence within steady cluster collection. Experimental results show that this approach can achieve higher correct detection rate, real-time detection and processing.
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Computer Engineering. 2011, 37(24): 64-66. https://doi.org/10.3969/j.issn.1000-3428.2011.24.021This paper proposes a dynamic rate adaptation Media Access Control(MAC) strategy for multi-rate IEEE 802.11 wireless LAN based on threshold adjustment. In the protocol, two groups of success thresholds are set respectively for fast-fading and slow-fading wireless channels. Each group of success thresholds is tuned by an improved Binary Exponential Backoff(BEB) algorithm. Without any change to the current 802.11 standard, the protocol facilitates its implementation. Simulation results show that the new scheme outperforms other existing schemes including the Auto Rate Fallback(ARF) scheme and its variants.
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Computer Engineering. 2011, 37(24): 67-70. https://doi.org/10.3969/j.issn.1000-3428.2011.24.022In order to adapt the demand of flat network management, this paper presents a Service-oriented Architecture(SOA) network management system. The paper designs service-orient network management system integration framework which consists of customer service operating platform, user portal, service design environment, and service management system, introduces the conception of network management interface simulation in order to achieve network management system development and performance evaluation, and uses the network simulation environment to provide real-time network information for the upper network management system to verify the function of the system and shorten the system development cycle. Experimental results show that the system can efficiently complete the network management tasks.
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Computer Engineering. 2011, 37(24): 71-73. https://doi.org/10.3969/j.issn.1000-3428.2011.24.023This paper presents a fast low-cost algorithm of delay-constrained dynamic multicast routing. When adding multicast nodes, it uses improved delay-constrained shortest path subgraph to avoid searching non-delay-constrained shortest path, which greatly improves the efficiency of the algorithm. By sharing longest shortest path as much as possible, it greatly reduces total cost of constructing multicast tree. Simulation results show that this algorithm has less computation time and low multicast tree total cost than Shortest Best Path Ttree(SBPT) algorithm, and multicast tree is more stable.
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Computer Engineering. 2011, 37(24): 74-76. https://doi.org/10.3969/j.issn.1000-3428.2011.24.024In this paper, a proportional rate constraints algorithm based on single carrier frequency division multiple access system, used for dynamic subcarrier allocation is proposed. The proposed algorithm utilizes appropriate allocation constrains to achieve the channel capacity resources allocation fairness for each user, thereby realizing the design of proportional rate constraints algorithm. On this foundation, a simplified algorithm is also proposed. Experimental results show that the algorithm can effectively improve the system capacity and guarantee the fairness, its simplified algorithm have good distribute performance and low calculation complexity.
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Computer Engineering. 2011, 37(24): 83-85. https://doi.org/10.3969/j.issn.1000-3428.2011.24.027For targets coverage in directional sensor network, this paper presents a target coverage method based on immune algorithm in directional sensor network. It chooses the directional sensors as few as possible that can monitor all targets. Simulation experimental results show that the simulation time of immune algorithm decreases about one third compared with genetic algorithm, and the performance of immune algorithm is better, the number of sensors decreases also after the operation.
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Computer Engineering. 2011, 37(24): 86-87. https://doi.org/10.3969/j.issn.1000-3428.2011.24.028Targeting the performance requirements of connection management in high-speed networks, an optimization of connection management is proposed, applying Move to Front(MTF) heuristic to improve the lookup operation of connection table. The locality property of network traffic is analyzed, which is exhibited as a group of packets within a connection probably arrive in group in a short time. Based on the property, the MTF heuristic is applied to optimize the lookup operation of connection table, and get the MTF connection table. The implementation of optimized connection management is described. The optimization and the MTF connection table, with physical high-speed network traffic are evaluated. Experimental results indicate that the lookup performance of MTF connection table is superior to that of the traditional sorted connection table.
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Computer Engineering. 2011, 37(24): 88-90. https://doi.org/10.3969/j.issn.1000-3428.2011.24.029This paper presents the basic structure of the network layer protocol SCPS-NP in the satellite communication protocol, introduces the match algorithm principle with wildcard, and proposes a new space transfer protocol identification algorithm Grammatical_BM which is based on grammar analysis idea, verifies it through simulation experiment. Experiment result shows that this method shields the pattern string shortage problem efficiently, and solves the problem of large wildcards in pattern string. Compared with former match algorithm principle with wildcard, it can reduce the algorithm complexity and improve the identification efficiency at the case of improving package number.
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Computer Engineering. 2011, 37(24): 91-93. https://doi.org/10.3969/j.issn.1000-3428.2011.24.030This paper proposes a GMM-based application-layer protocol identification technique of ESP traffic. It uses two means to construct the ESP traffic data sets, one is synchronous collection, another is traffic simulation, And builds and tests the GMMs of HTTP, FTP, SMTP and TELNET on the data sets. Result shows GMM is applicable to identify the application-layer protocol of the ESP traffic, and the network-layer characteristics of the ESP traffic leak enough information to identify other application-layer protocol.
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Computer Engineering. 2011, 37(24): 94-96. https://doi.org/10.3969/j.issn.1000-3428.2011.24.031In order to reduce the routing overhead, probability of the information collision and rate of the link breaks in hierarchical Ad Hoc networks, a new inter-cluster routing algorithm based on the link reliability is proposed and described. Based on the research of the characteristics of the classification structure and inter-cluster routing, several key parameters in the inter-cluster routing are discussed and the corresponding weight parameter is defined. The weight parameter is mapped to the variables of Ant Colony Algorithm(ACA), so as to meet the demand of the network. And this ant colony optimization algorithm is applied to the inter-cluster routing. Simulation results show that the new algorithm is effective to reduce the flooding overhead, increase the probability of optimization and enhance the reliability of inter-cluster routing.
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Computer Engineering. 2011, 37(24): 97-99. https://doi.org/10.3969/j.issn.1000-3428.2011.24.032Lowering the energy consumption may result in higher latency Wireless Sensor Network(WSN). To address such a tradeoff, this paper proposes a Media Access Control(MAC) protocol based on dynamic duty cycle. It adjusts duty cycle dynamically based on utilization, average sleeping delay, and the upper and lower bound of duty cycle. Experimental results show that the MAC protocol saves energy about 52% and reduces latency by 35% from S-MAC in a chain topology. In the cross topology, it achieves 68% energy saving and 46% latency reduction from S-MAC.
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Computer Engineering. 2011, 37(24): 100-102. https://doi.org/10.3969/j.issn.1000-3428.2011.24.033The traditional secret sharing scheme has defects in preventing cheating between participants. Based on systems of linear equations, this paper proposes a new scheme. Before the recovery phase, the new scheme needs two steps in which authorized participants shares must be verified, and it is shown that any participant who has passed the verification in these two steps must be honest. The new scheme is more safer than the other vector space secret sharing schemes.
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Computer Engineering. 2011, 37(24): 103-105. https://doi.org/10.3969/j.issn.1000-3428.2011.24.034To assess the biometric cryptosystem performance in possible side-channel attacks, on the basis of analysis of the biometric cryptosystem structure and characteristics, a secure biometric cryptosystem based on the keystroke is designed by the combination of the user's keystroke biological characteristics and secret sharing scheme. Power consumption leakage of the safe biometric cryptosystem is measured with the Differential Power Attack(DPA). Simulation analysis shows the biometric cryptosystem can be extracted with bits of power leakages.
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Computer Engineering. 2011, 37(24): 106-108. https://doi.org/10.3969/j.issn.1000-3428.2011.24.035This paper analyzes the existing security of the forward secure ring signature scheme, points out that the scheme exists security omission because of lacking forward security. Aiming at these problems, it proposes an improved forward-security ring signature scheme. The defect that the original scheme is signed with constant is overcome by changing the algorithm of ring signature. The algorithm combines the updating secret key and ring signature. The analysis of security and efficiency shows that the improved scheme has forward security, unconditional anonymity and resisting forging attack, as well as higher signing efficiency.
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Computer Engineering. 2011, 37(24): 109-111. https://doi.org/10.3969/j.issn.1000-3428.2011.24.036This paper analyzes the problems of the password guessing dictionary attacks and message replay attacks in current Kerberos protocol. An improved single sign-on protocol is proposed. The prevention of password guessing dictionary attacks is achieved by adding a random number and employing a dynamic key in authentication messages. The resistance of replay attacks is realized by marking the message between a client and its corresponding server with a unique serial number. Experimental results show that the improved protocol is valid.
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Computer Engineering. 2011, 37(24): 112-113. https://doi.org/10.3969/j.issn.1000-3428.2011.24.037In order to defend both Invalid Curve Attack(ICA) and Sign Change Fault Attack(SCFA) at the same time, and avoid embranchment operation, this paper proposes an elliptic curve point multiplication algorithm which can resist fault attack by using randomization technology and fault infective computation. Theory analysis proves that the algorithm can defend ICA and SCFA effectively, and its redundancy computation is less, which influences chips little.
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Computer Engineering. 2011, 37(24): 114-116. https://doi.org/10.3969/j.issn.1000-3428.2011.24.038A proxy blind signature scheme is analyzed. It is found that proxy blind signature generation phase in this scheme is not secure, adversaries can easily find out the proxy key due to improper use of pre-computation. To resolve the problem, this paper proposes a new ID-based proxy blind signature scheme which satisfies the required security properties of unforgeability and blindness. It has lower computing complex compared with other schemes.
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Computer Engineering. 2011, 37(24): 117-119. https://doi.org/10.3969/j.issn.1000-3428.2011.24.039This paper designs a new kind of image encryption algorithm which uses two Logistic systems. The auxiliary key m is obtained by a certain line data of the changed image matrix. The initial values of two Logistic mappings are modified by the key m. The Logistic mappings are used to generate the encryption sequences which are used to encrypt with every pixel of the image. Theoretical analysis and simulation results show the new algorithm not only has better sensitivity and very uniform pixel-value distribution, but also is simple and easy to achieve.
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Computer Engineering. 2011, 37(24): 120-122. https://doi.org/10.3969/j.issn.1000-3428.2011.24.040This paper presents a design scheme with low power consumption oriented to security domain called Application Specific Instruction-set Processor(ASIP) which also achieves high performance and flexibility. The instruction Read Only Memory(ROM) is divided into two parts, one of which can be power gated in some cases. The clock-gating method is used to cool the registers in the register file unit. The operator latches are added in front of the EXE stage so that the idle function units can avoid unnecessary switches. Experimental results show the scheme reduces the power of the core part of security ASIP and the whole design including storage elements by 30% and 16% on average respectively.
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Computer Engineering. 2011, 37(24): 123-125. https://doi.org/10.3969/j.issn.1000-3428.2011.24.041Based on the existing dynamically updated key management scheme on Wireless Sensor Network(WSN), this paper improves its flaw of no identity authentication and weak scalability by adding identity authentication modules and proposes a new key management scheme and a feasible new node joining mechanism on WSN. Compared with the original one and similar key management schemes, this scheme maintains efficiency while ensuring higher security and bringing in better scalability, network connectivity and other features.
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Computer Engineering. 2011, 37(24): 126-128. https://doi.org/10.3969/j.issn.1000-3428.2011.24.042This paper analyzes the security issues of an efficient identity-based signcryption scheme S-IDSC. It indicates its lack of the security characteristics of forward security and public verifiability. An improved signcryption scheme E-IBSC is proposed. Security analysis shows that E-IBSC can satisfy the generic security requirements of signcryption schemes. Performance analysis shows that E-IBSC maintains the equivalent computational overheads with only additional acceptable communication load.
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Computer Engineering. 2011, 37(24): 129-131. https://doi.org/10.3969/j.issn.1000-3428.2011.24.043In distributed systems, the user’s identity is uncertain, the access platform is complex, and the network environment is changeable. The traditional simplex access control model such as role-based or identity-based access control model can not well meet the requirements. It combines the advantage of Role-based Access Control(RBAC) and Trust Management(TM), extends the traditional RBAC model with the notion of trust and context, performs a multidimensional measurement on user’s identity, access platform and user’s behavior, considering the security of user’s platform and the dynamic uncertainty of the network environment, promotes a new access control model called MCBAC. It is according to user’s identity information and trust degree assign roles. It realizes dynamic role authorization control. It has good security and flexibility.
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Computer Engineering. 2011, 37(24): 132-135. https://doi.org/10.3969/j.issn.1000-3428.2011.24.044This paper proposes a key agreement protocol in satellite network based on bilinear pairings. It analyzes the characteristics of the satellite network and gives the implementation procedure of the protocol. Security analysis demonstrates that the key agreement protocol can resist active and passive attacks without key trusteeship problem and the key generating process is uncontrolled. Performance analysis demonstrates that the protocol can increase the efficiency of the session key agreement, it is more satisfied with needs of key generation in real satellite network.
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Computer Engineering. 2011, 37(24): 136-137. https://doi.org/10.3969/j.issn.1000-3428.2011.24.045To solve the problem of the Hash algorithm expansibility based on the Chip Operating System(COS), a flexible Hash interface is designed. The interface which takes the object-oriented thought is made up by Hash algorithm interface and Hash algorithm setting interface. The Hash algorithm interface is set by the Hash algorithm setting interface, which is stored in the EEPROM, to be an instance and has the capability to provide the cryptographic service. The results of experiment show that Hash interface has good expansibility to add other algorithms, and get the purpose to design it.
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Computer Engineering. 2011, 37(24): 138-140. https://doi.org/10.3969/j.issn.1000-3428.2011.24.046Toward the basic exemplar-based recognition method is hard to apply in real-time gesture recognition for the huge amount of data, the Haar wavelet can be used to decompose images to keep the detail parts and discard the high-frequency parts, where each frame image in the video sequence can be downsized to the minimal level such that no obvious effect on the system’s accuracy and the computational cost in the recognition stage can be saved. Comparing by the experiment with a single Web camera on a 36 elements of American sign language gesture dataset, the results show that the effective system recognition can be sped up to 30 f/s with the same accuracy, which meets real-time requirement.
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Computer Engineering. 2011, 37(24): 141-143. https://doi.org/10.3969/j.issn.1000-3428.2011.24.047Aiming at similarity and instability of gesture activity signal in gesture interaction, a gesture recognition scheme based on three-axial accelerometer is presented. It utilizes a MMA7260 accelerometer to capture the acceleration signal of dominant wrist. An activity detection algorithm is used to auto determine the data stream which containing interesting motion according to the features of gesture activity signal. After denoising and resampling the acceleration data streams, gesture features are extracted, and Discrete Hidden Markov Model(DHMM) is built for gesture recognition. Experimental results demonstrate the effectiveness of the scheme.
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Computer Engineering. 2011, 37(24): 144-146. https://doi.org/10.3969/j.issn.1000-3428.2011.24.048This paper proposes a video text localization method based on Local Binary Pattern(LBP) and Fuzzy Support Vector Machine(FSVM). The edge detection and morphological operations are used to the video images. The candidate text regions are detected using project analysis and heuristic rules. The final results are defined using FSVM, in which LBP that describes the local edge distribution are used as input features. Experimental results show that the performance of this method is well and it has stronger robustness.
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Computer Engineering. 2011, 37(24): 147-149. https://doi.org/10.3969/j.issn.1000-3428.2011.24.049To reduce the dimensionality of the Gabor feature, this paper presents a novel approach called Gabor Phase-based Texture Representation(GPTR) for face recognition. GPTR is characterized by using the Generalized Gaussian Density(GGD) to model the Gabor phase distribution. The estimated model parameters serve as texture representation, which is then analyzed by Locality Preserving Projections(LPP) to make them more discriminative. Experimental results on FERET and Yale databases show that GPTR is superior to traditional Gabor features in terms of recognition accuracy.
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Computer Engineering. 2011, 37(24): 150-151. https://doi.org/10.3969/j.issn.1000-3428.2011.24.050The influence of the illumination, expression and the angle and so on may enhance the time complexity and space complexity of the data computation greatly during the face recognition, so this paper proposes a new statistical model for image appearance. Active Shape Model (ASM) is introduced in Grey Level Co-occurrence Matrix(GLCM). By calculating the GLCM under the shape of the image alignment, Semi-active Appearance Model(SAAM) is established. Experiments on the standard ORL face database show that compared with ASM, the model gains higher recognition rate and speed.
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Computer Engineering. 2011, 37(24): 152-154. https://doi.org/10.3969/j.issn.1000-3428.2011.24.051A multi-objective evolution algorithm based on good point set is proposed to tackle restraint optimization problems. Good point set in number theory and multi-objective optimization methods are integrated into algorithm. Restraint optimization problem is transformed into a bi-objective optimization problem. Combined with the principle of good point set, it makes the individuals in search space distribute more evenly. The new mutation operator is applied for enhancing the diversity of the offspring population. A sub-swarm local search operator with Pareto non-dominated is used to choose the best individuals for the next population. Experimental results show that the algorithm has good stability.
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Computer Engineering. 2011, 37(24): 155-157. https://doi.org/10.3969/j.issn.1000-3428.2011.24.052In order to realize landmark tracking by Unmanned Aerial Vehicle(UAV), this paper embeds online feature selection into particle filtering algorithm, and adopts adaptive transition model. Candidate feature set is composed of linear combination of R, G and B pixel values. Histograms of feature values for pixels on the object and in the background are computed for obtaining log likelihood ratio and variance ratio. The feature with the best discrimination is selected for computing the likelihood image. Two sets of particles are obtained via different approaches for estimating the position of the object. Experimental results show that the algorithm provides more reliable results and it is more robust.
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Computer Engineering. 2011, 37(24): 158-160. https://doi.org/10.3969/j.issn.1000-3428.2011.24.053In order to take advantages of expired training data and correlation data structures to achieve the aim of learning new areas, this paper proposes a transfer learning approach based on Markov Logic Network(MLN). It autonomously maps the predicates on the source and target, and optimizes the mapping structure by self-diagnosis, structure update and new formula mining. Experimental results show that compared with traditional method, the probabilistic reasoning to the target domain MLN structure to gain higher accuracy of the results with less learning time and training data.
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Computer Engineering. 2011, 37(24): 161-163. https://doi.org/10.3969/j.issn.1000-3428.2011.24.054Non-negative Matrix Factorization(NMF) with dual constraints method for document clustering is proposed. It is based on NMF model with adding of pair-wise constraints on documents and categorization constraints of the words. Iterative rules obtained from the original word-document matrix are decomposed to get document clustering results. Compared with a variety of popular semi-supervised clustering algorithm, the method for document clustering can effectively improve the accuracy of document clustering, and can provide more accurate and efficient clustering results.
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Computer Engineering. 2011, 37(24): 164-166. https://doi.org/10.3969/j.issn.1000-3428.2011.24.055Based on analyzing the features of REST and RESTFUL service, the concept of designing service-oriented computing for Genetic Algorithm(GA) in REST style is presented, which realizes distributed genetic evolving with two sorts independent service processes that call each other by verb PUT and POX encoding format. An intelligent test paper system taking advantage of distributed paralleling genetic algorithm running RESTFUL service is developed by Window Communication Foundation(WCF). Experimental results show that the algorithm is proved to have high operational efficiency.
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Computer Engineering. 2011, 37(24): 167-168. https://doi.org/10.3969/j.issn.1000-3428.2011.24.056An abandoned objects detection method based on double background is presented in this paper. Sliding average model and improved Gaussian Mixture Model(GMM) are used respectively to construct separate reference and dynamic background. Compared the two prospects of the two layers, static object and ghost are labeled. Ghost can be eliminates by using the histogram matching method with the stationary objects. Based on the foreground detection, Mean Shift algorithm and particle filter algorithm are used to tracking. Experiment results prove the validity of the method.
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Computer Engineering. 2011, 37(24): 169-172. https://doi.org/10.3969/j.issn.1000-3428.2011.24.057This paper proposes a Chinese Semantic Role Labeling(SRL) based on phrase and dependency syntactic structure. Combining the features of phrase and dependency syntactic structure, syntax tree are pruned, filtrates group piece phrases unit and relationship nodes of syntax tree which can’t assume semantic role, labels role category for group piece and nodes which assume semantic role. Recognition results show that the nominal SRL approach achieves the performance of 73.53% in F1-measure on golden parse trees and golden predicates.
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Computer Engineering. 2011, 37(24): 173-175. https://doi.org/10.3969/j.issn.1000-3428.2011.24.058In Particle Swarm Optimization(PSO) algorithm, many particles may exceed the limit of positions when searching the global best. In order to overcome the problem, a new group of restricted boundary conditions, which relocate the arrant particles randomly in the solution space are proposed. The performances of the five new boundary conditions and six existed boundary conditions are tested based on two benchmark functions. Simulation results are examined from both the global best and convergence rate of the algorithm. Comparisons show the performance of the new restricted boundary conditions are much better than that of the boundary conditions relocated in the boundary, and the invisible/absorbing boundary condition edges out other unrestricted boundary conditions.
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Computer Engineering. 2011, 37(24): 176-179. https://doi.org/10.3969/j.issn.1000-3428.2011.24.059According to the complexity of sunspots, this paper uses Empirical Mode Decomposition(EMD) method, the solar activity contains all of the time scale changes separated into the inherent weight smooth Intrinsic Mode Function(IMF) and remainders. It observes each component of the spectrum, based on the characteristics of the low frequency IMF component selection Auto-regressive Moving Average(ARMA) model predicted the average directly, and the high frequency IMF using neural network forecast. Through the various components of the primary signal reconstruction predicts a prediction sequence, and increases the prediction accuracy. Simulation results show that the model has higher forecast accuracy.
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Computer Engineering. 2011, 37(24): 180-182. https://doi.org/10.3969/j.issn.1000-3428.2011.24.060An algorithm for fast tracking multi-targets in image sequences of video is proposed to solve the problem of collision and cover in targets tracking. Kalman algorithm is applied to predict the position of the targets, and color match algorithm is used to determine the fast match of the targets between two frames in this algorithm, and the states of the targets are determined by building the Markov model and analyzing the confidences of the targets to avoid the interference of collision and cover, so that the targets can be tracked accurately. Experimental results indicate that this algorithm can be used to solve the problems of collision and cover in multi-target fast track.
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Computer Engineering. 2011, 37(24): 183-186. https://doi.org/10.3969/j.issn.1000-3428.2011.24.061To solve subtask allocation problem, a Particle Swarm Optimization(PSO) algorithm is proposed by designing a dual coding method. Pre-constraint is used to produce population. A search strategy based on harmony search is brought into PSO algorithm to avoid its defect of easily plunging into the local optimum. Simulation results of the the classical cases and comparison to other algorithms demonstrate the effectiveness of this algorithm.
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Computer Engineering. 2011, 37(24): 187-189. https://doi.org/10.3969/j.issn.1000-3428.2011.24.062This paper proposes a novel face recognition algorithm of 2D Nonparametric Subspace Analysis(2DNSA) based on 2D Principal Componet Analysis(2DPCA) subspace. The original face matrices are performed to have feature dimension reduction, and the reduced feature matrices are used as a new training set, which can be conducted by 2D non-parametric subspace analysis. This method not only can reduce feature dimensions by 2DPCA, but also consider the impact of boundary samples for classification by taking full advantage of classification capacity of 2DNSA, which avoids the irrationality of using class centers to measure the distances of different classes. Experimental results on the two face databases(namely Yale and LARGE) show the improvements of the developed new algorithm over the traditional subspace methods such as (2D)2PCA, 2DPCA, (2D)2LDA, 2DLDA, 2DPCA+2DLDA, 2DNSA, etc.
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Computer Engineering. 2011, 37(24): 190-192. https://doi.org/10.3969/j.issn.1000-3428.2011.24.063Ant Colony Algorithm(ACA) has some short-comings such as its slow computing speed, and it is easy to fall in a local optimal. Based on the idea of ACA, a hybrid optimization algorithm for solving Vehicle Routing Problem(VRP) is proposed. The algorithm expands the scope of solution space and improves the global ability of the algorithm by importing mutation operator, optimizes the stage optimal solution further by combining 2-opt, and controls the rate of change in pheromone by adjusting configuration of parameters dynamically. Example simulation results show that this algorithm can get optimal resolution of VRP effectively and quickly.
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Computer Engineering. 2011, 37(24): 193-194. https://doi.org/10.3969/j.issn.1000-3428.2011.24.064This paper presents a dimensionality reduction algorithm based on pair-wise constraints and sparsity preserving. It combines some supervised information in the form of pair-wise constraints and large number of unsupervised information. It uses pair-wise constraints to discriminant analysis and uses sparse representation to preserve the sparse reconstructive structure in the transformed space. Compared with the traditional feature extraction method, this algorithm has a better recognition impact, lower parameters, and better robustness.
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Computer Engineering. 2011, 37(24): 195-197. https://doi.org/10.3969/j.issn.1000-3428.2011.24.065This paper proposes an orthogonal wavelet transform fractionally spaced constant modulus blind equalization algorithm based on the optimization of Quantum Particle Swarm Optimization(QPSO). It analyzes of the futures of the quantum-behaved particle swarm optimization algorithm and orthogonal wavelet transform. The algorithm can reduce the autocorrelation of the input signals, and the equalizer weight vector can be optimized by QPSO algorithm with the characteristics of high searching ability, rapid convergence and high robustness. Simulation result shows that this algorithm can reduce steady mean square error, improve convergence rate and no distortion transmission performance of signal in underwater acoustic channels.
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Computer Engineering. 2011, 37(24): 198-199. https://doi.org/10.3969/j.issn.1000-3428.2011.24.066The traditional Local Linear Embedding(LLE) algorithm is sensitive for the number of nearest neighbors, and fails on sparse source data. In order to solve this problem, a local linear embedding algorithm based on the geometric distance perturbation is proposed. The local linear property of the manifold data is described by geometric distance perturbation. The original dataset is set into some maximal linear block according to the perturbation. The LLE is applied to this maximal linear patch to complete the embedding dimensional-reduction. Experimental results demonstrate this method can raise the average accurate rate.
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Computer Engineering. 2011, 37(24): 200-203. https://doi.org/10.3969/j.issn.1000-3428.2011.24.067Performance of the traditional Super-resolution(SR) algorithm will degrade in intensive noise environment. In this paper, a novel kurtosis based SR method is proposed which is robust for SR reconstruction from Low-resolution(LR) images with low SNR. The definition of the kurtosis image is given and its two properties are analyzed: (1)The kurtosis image is Gaussian noise invariant; (2)The smoother the image is, the smaller the absolute value of a kurtosis image. The SR image is estimated by maximizing the local absolute kurtosis with the constraint that the reconstructed image is consistent with the observed data of the same image. The constraint optimization problem is solved by using the Lagrange multiplier method. The proposed algorithm is tested on images corrupted by a Gaussian noise and non-Gaussian noise. Experimental results demonstrate that the proposed method is superior both on subjective and objective evaluation.
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Computer Engineering. 2011, 37(24): 204-206. https://doi.org/10.3969/j.issn.1000-3428.2011.24.068Aiming at the application requirement of real-time edge detection in image sequences, an anti-noise Sobel edge detection algorithm is proposed, and its hardware-accelerated design is developed. The algorithm structure is optimized by replacing two-dimensional median filter with separate median filter and improving the computation of the magnitude and orientation of the gradient. Several measures such as improving the hardware architecture of separate median filter, storing the temporary data to avoid computing repeatedly and calculating the magnitude and orientation of the gradient in parallel are taken to improve the real-time performance and reduce the hardware resources cost. Simulation results of ModeSim and the synthesis report of ISE illuminate that the hardware-accelerated can accclerate the speed and reduce the hardware resources consumption. The proposed algorithm performs better in noise immunity and edge detection performance.
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Computer Engineering. 2011, 37(24): 207-209. https://doi.org/10.3969/j.issn.1000-3428.2011.24.069To solve the problem of the difficulty in side-scan sonar image edge detection, a muti-scale edge detect method based on the characteristic of side-scan sonar image is proposed. Side-scan sonar image is decomposed in Non Sampling Contourlet Transform(NSCT) domain and image is denoised locally and adaptively according to the characteristic of speckle noise in NSCT domain. Maximum modulus points are found by interpolation in the direction of edge and non-maximum suppression. The threshold is automatically determined based on minimum interclass variance algorithm and the edge of each subband is acquired by thresholding. The binary edge map is obtained by edge fusing. Edge detection results show that the proposed method has the advantages of edge integrity, positioning accuracy and fewer false edge points.
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Computer Engineering. 2011, 37(24): 210-212. https://doi.org/10.3969/j.issn.1000-3428.2011.24.070Most traditional image fire detection technologies detect fire based on flame space feature such as flame color, boundary and so on, studies lack in image frequency domain. So an image fire detection algorithm based on Amplitude spectrum of boundary chain-code is presented. It converts the chain-code to a sequence array and obtains the amplitude distribution with FFT, analyzes the frequency domain of the image and obtains the relationship of spatial domain features and frequency domain distribution. Amplitude spectrum of boundary chain-code analysis is applied in the research of the image fire detection. Simulation results show the effectiveness of the algorithm.
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Computer Engineering. 2011, 37(24): 213-215. https://doi.org/10.3969/j.issn.1000-3428.2011.24.071A novel shape description algorithm in satellite remote sensing image is proposed based on the wavelet transformation. Images are decomposed by one-scale wavelet transform, the feature vectors are extracted by Hu moment, Zernike moment and the Fourier descriptor respectively, and the feature vectors are weighted according to each sub-wave band’s description ability. The feature vectors are put into the classifier to examine their description abilities. Experimental results demonstrate that the new algorithm has superior performance for more accurate description of the target shape. Compared with classical descriptors, its performance is much higher.
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Computer Engineering. 2011, 37(24): 216-218. https://doi.org/10.3969/j.issn.1000-3428.2011.24.072This paper proposes a new algorithm for 2D adaptive lifting wavelet transform, which suites for the task of image compression applications. It is based on an update lifting operator and a prediction lifting operator according with p-order AR model of an image. It can get the coefficients of the predict filter to minimize the power of predictor error. Experimental results show that the proposed algorithm is competitive for the image compression, in terms of the decrease of the entropy of the detail coefficients and the increase of the PSNR.
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Computer Engineering. 2011, 37(24): 219-221. https://doi.org/zhoujl1122@126.comThe color migration effect of traditional methods depends on the subjective evaluation, and has a big application limitations. This paper proposes an improved method of image color transfer. It chooses the best matched color of the reference color area from the multiple source images by the brightness fitting, category selection. For the color images, the various regions of the target image are smoothed by using the probability of membership function, and the synthetic value of color transfer is computed by using the mean and variance of the reference color area; for the grayscale images, the components of reference and source color image are normalized, the gray level is divided, and the membership is weighted by the Sigmoid function, to achieve the color migration of gray images. Experimental results show that the improved method can generate convincing results with well performance in terms of objective evaluation or visual effects.
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Computer Engineering. 2011, 37(24): 222-224. https://doi.org/10.3969/j.issn.1000-3428.2011.24.074According to the problem of large amount of Scale Invariant Feature Transform(SIFT) algorithm, this paper constructs pyramid feature descriptor by using concentric squares, calculates every seed vector quickly by using recursion algorithm, and maintains the rotation invariant of algorithm by simply ranking the vector. It puts forward a matching search method which is suitable for the descriptor. Experimental results show that the algorithm can increase the matching speed, and can identify target effectively under rotate and zooming.
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Computer Engineering. 2011, 37(24): 225-227. https://doi.org/10.3969/j.issn.1000-3428.2011.24.075According to the characteristics of Wireless Sensor Network(WSN) that the heterogeneity of specific application implementation and massive data, this paper illustrates an implementation which WSN structure is built on Crossbow hardware and base station and is used to obtain vineyards environment arguments such as soil, air and radiation data. In order to implement data reception and forwarding, when one or one more base stations connect to it, this paper implements a Parallel Monitoring and Control System(PMCS) mechanism. It is used to monitor multiple base stations’ connection request for receiving and forwarding sensor data, while parsing data in XML format and storing the valid data into Oracle database. It facilitates the development of Web client applications. So it implements the flexible configuration of heterogeneous data and the timely response and cooperative work to service requests from multiple base stations.
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Computer Engineering. 2011, 37(24): 228-229. https://doi.org/10.3969/j.issn.1000-3428.2011.24.076A concept of Joint Test Action Group(JTAG) boundary scan technology is proposed. The key components and related commands are introduced. A universal Flash simulator focusing on the engineering application is introduced. Based on the traditional JTAG on-line simulator, it adds the use of FPGA. It makes full use of the advantage of parallel transmission of parallel port and break through the speed bottleneck of the traditional JTAG on-line simulator. With self-identified communication protocol, it not only improves the reliability and security of the communication, but also realizes a higher performance than the traditional JTAG on-line simulator.
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Computer Engineering. 2011, 37(24): 230-232. https://doi.org/10.3969/j.issn.1000-3428.2011.24.077The fuzzy control dynamic look-up table is developed under the graphical programming language LabVIEW for the controlled target which has the non-liner characteristic, the pure lag and the multivariable in the industrial process controlling. Depoly the dynamic look-up table calculated by compositional rule of inference to the NI Compact Filed Point(CFP)-2120 controller which runs the embedded LabVIEW application programs under the extreme environment, and the three-level series tank level system is real-time controlled. Experimental results show that the fuzzy controller has the excellent performance without overshoot, non oscillation and small static error, and a new method is provided to realize the fuzzy control under the LabVIEW program.
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Computer Engineering. 2011, 37(24): 233-235. https://doi.org/10.3969/j.issn.1000-3428.2011.24.078Aiming at the defects of the fault diagnosis in aircraft Constant Speed Constant Frequency Alternation Current(CSCF-AC) power supply, this paper proposes a new diagnosis method based on the Dynamic Fault Tree(DFT) and network. By adding a new operator BEFORE to the usual Boolean operators in the qualitative analysis of the DFT, this method provides a complete qualitative description of the system, and that any failure distribution can be accommodated. Then a 3-layer networked diagnosis system, which includes built-in test equipment in aircraft, diagnosis center on the ground, and remote experts from airlines, aircraft manufacturers or research institutes, is designed and developed. Experiments in the local area network show that the diagnosis method is effective and reliable, and the engineering effectiveness of the system is verified.
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Computer Engineering. 2011, 37(24): 236-238. https://doi.org/10.3969/j.issn.1000-3428.2011.24.079To improve shortcoming of traditional arbiters, this paper proposes N-way ordered arbiter, which is based on combination of First In First Out(FIFO) and priority arbiter and ring arbiter respectively. FIFO is used for savingthe request orders. It proposes a new structure of priority and a new ring arbiter. Results show that, modular design simplifies the complexity, improves the ability of arbiter to process the request, and the ability of saving the request in order reduces latency and area properties.
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Computer Engineering. 2011, 37(24): 239-241. https://doi.org/10.3969/j.issn.1000-3428.2011.24.080The amount of computation is huge as a result of the Chirp Scaling(CS) algorithm’s complicated phase factor expression. To solve this problem, a hardware-software co-design method which is based on phase compensation factor and suitable for real time image processing is proposed. Taking advantages of the feasibility of numerical calculation by software and the high efficiency of computation by programmable logic, it can generate and compensate the phase factor quickly and efficiently. Theory analysis and experimental results sThe amount of computation is huge as a result of the Chirp Scaling(CS) algorithm’s complicated phase factor expression. To solve this problem, a hardware-software co-design method which is based on phase compensation factor and suitable for real time image processing is proposed. Taking advantages of the feasibility of numerical calculation by software and the high efficiency of computation by programmable logic, it can generate and compensate the phase factor quickly and efficiently. Theory analysis and experimental results show the efficiency of the method.how the efficiency of the method.
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Computer Engineering. 2011, 37(24): 242-244. https://doi.org/10.3969/j.issn.1000-3428.2011.24.081This paper creates an embedded system’s platform centering the microprocessor 88F6281 and based on Double Data Rate 2(DDR2) technique, it can also connect with hard-disks. Because of strict demand of the high frequency circuit to Signal Integrity(SI), it designs all subsystems of this platform on principle of circuits and printed circuits board, such as main memory subsystem, hard-disk’s interface subsystem, power supply subsystem. The platform can be efficiently used in many different applications of embedded system that needs high performance and large numbers of supplementary storage spaces. This platform works well and stably in the test to it.
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Computer Engineering. 2011, 37(24): 245-246. https://doi.org/10.3969/j.issn.1000-3428.2011.24.082To solve the problem of vehicle type recognition, a novel algorithm is proposed. The background reconstruction is proposed based on difference frame sequence. The vehicle detection is finished based on background difference method and the shadow elimination is based on LBP texture analysis method. The concept of projection of vehicle shape is proposed, the 2D information of vehicle shape is reduced dimensionality and the robustness of algorithm is increased. A two-input fuzzy classifier is designed and the high-precision multi-class accurate vehicle recognition is finished by using the projection of vehicle shape and the ratio of height and length. Experimental results prove the validity and practicability of the algorithm.
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Computer Engineering. 2011, 37(24): 247-250. https://doi.org/10.3969/j.issn.1000-3428.2011.24.083This paper takes Shanghai Expo Park as an case, proposes the system logic framework and software design method of energy and environment monitoring WebGIS based on Linux. It anaylzes the key technologies including map server pooling, map cache management, dynamic map rendering and cross domain data access on Web etc., and gives the implementation method of the system modules. The study production has carried out the mission of monitoring and analysis on the energy and environment in Shanghai Expo Park successfully.
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Computer Engineering. 2011, 37(24): 251-253. https://doi.org/10.3969/j.issn.1000-3428.2011.24.084This paper uses the Phase Change RAM(PCRAM) as the main memory of Imagine stream processor, studies the performance optimization of it. It builds the performance analysis model of PCRAM. In order to enhance the limited PCRAM write endurance, it uses redundant bit-writes removal technology to extend the endurance of PCRAM to an average 3.4x longer. It uses nonvolatile feature to avoid not necessary row buffer write back. It analyzes the memory access schedule algorithms, and results show that the row/open memory access schedule algorithm is suitable for PCRAM.
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Computer Engineering. 2011, 37(24): 254-256. https://doi.org/10.3969/j.issn.1000-3428.2011.24.085The commercial Geographic Information System(GIS) software has a large scale. The costs are too high in secondary small-scale system development. In this paper, framework design and development are carried out based on the open source class library of SharpMap. Commands and tools are as the smallest unit. Feature refinements to some command or tool. Depending upon the needs of development, commands and tools are integrated together to form a system in accordance with the category. Experimental results prove the method is very flexible in application of secondary development. Developed tools and commands can be reused in multiple projects.
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Computer Engineering. 2011, 37(24): 257-259. https://doi.org/10.3969/j.issn.1000-3428.2011.24.086A two-phase multi-objective decision method is proposed to the multi-objective decision of aircraft environmental control system and engine. The total entropy generation minimum at flight phases of take-off, climb and supersonic penetration are regarded as different objective, the multi-objective optimization model is established. The Pareto optimal set is obtained by multi-objective optimization algorithm. Based on the Pareto optimal set the scheme primary selection is done, and it evaluates the selected scheme through Vague set decision-making method with improved integrated weight, the final optimal scheme is obtained. Results validates the rationality of the method.
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Computer Engineering. 2011, 37(24): 260-262. https://doi.org/10.3969/j.issn.1000-3428.2011.24.087A global optimal algorithm based on Binary Particle Swarm Optimization(BPSO) is presented to resolve user needs in Web service composition. The mutation operation and linearly decreasing inertia weight are used to overcome the premature convergence of traditional BPSO. Based on the memory of particles, the individuals that do not conform to the constraint conditions are modified. Experimental results show that the algorithm can improve the searching efficiency.
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Computer Engineering. 2011, 37(24): 263-265. https://doi.org/10.3969/j.issn.1000-3428.2011.24.088In order to reduce the fault detection rate and improve the anti-fraud capacity in network fault detection, a multi-layer model for network fault detection is proposed based on the hierarchical structure of biological immune system. According to the differentiation mechanism of dendritic cells, an immune model composed of the inherent detection layer, fuzzy judgment layer and adaptive detection layer is established. It reduces the network fault detection rate through the double detection of inherent detection layer, fuzzy judgment layer and uses the adaptive detection layer to conduct self-learning on unknown faults. Experimental result shows that this model has high detection rate and low false reject rate.
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Computer Engineering. 2011, 37(24): 266-268. https://doi.org/10.3969/j.issn.1000-3428.2011.24.089This paper proposes an improved Least Squares Support Vector Machine(LS-SVM) parameter optimized selection method by combining Tabu Search(TS) and Genetic Algorithm(GA). Self-adaptive GA is used to search the global space and TS is used for searching the local area, so that the efficiency and precision of the solution are improved. A prediction model based on the method is established and simulated by the field data from the purification process in a smelt factory. Simulation results show that the method makes LS-SVM model have good generalization performance and high precision which can satisfy the technology requirement.
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Computer Engineering. 2011, 37(24): 269-271. https://doi.org/10.3969/j.issn.1000-3428.2011.24.090Aiming at the dissolve and fade in fade out phenomenon of video, this paper proposes a video shot detection algorithm based on three steps filter. A finite state machine is used to search gradual transition candidates in intensity variance continuity signal, and verify those to get real gradual transitions, next, extract color, texture and motion feature of video frame to guarantee the precision of gradual shot detection. Experimental results based on the videos from TRECVID demonstrate good performance of the algorithm and its robustness against disturbances caused by object motion or flashlight.
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Computer Engineering. 2011, 37(24): 272-274. https://doi.org/10.3969/j.issn.1000-3428.2011.24.091To address the processing problem of mass tag information which emerged from large scale Radio Frequency Identification(RFID) application, this paper proposes a design of embedded RFID middleware system based on multilevel data processing. There are two subsystems in this design, one is responsible for data acquisition and the other is responsible for data processing. Tag information is transferred to users after filter, sorting and restructuring. This design can increase the accuracy of data processing and then improve the efficiency of RFID application.
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Computer Engineering. 2011, 37(24): 275-277. https://doi.org/10.3969/j.issn.1000-3428.2011.24.092This paper presents a real-time display method of three-dimensional strata profile, this method uses the given Digital Elevation Model(DEM) data, it adopts cubic spline function curve to structure its outline line, it effectively solves the internal visualization of three-dimensional strata model. During the dredging, it uses sonar data to adjust the model dynamically for construction. Experimental results show that this method has fast calculation speed, high precision, the effect of real-time display can be achieved, and effectively improves the quality of dredging in trailing suction hopper dredger, reduces environmental impact.
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Computer Engineering. 2011, 37(24): 278-280. https://doi.org/10.3969/j.issn.1000-3428.2011.24.093Aiming at defects of the high computational complexity and hardly used in real-time application of H.264/AVC video encoding standard, by using reconstruction of macro-blocks motion vector and inter-frame prediction mode, and combining feature of Human Visual System(HVS), this paper proposes a fast extraction algorithm for video Region of Interest(ROI) and optimized encoding scheme. Simulation results show that compared with H.264/AVC algorithm, the proposed algorithm can achieve reduction of 53.11% encoding time on average, while PSNR only declined 0.052 dB and bit-rate increase 0.17% at the same time.
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Computer Engineering. 2011, 37(24): 281-283. https://doi.org/10.3969/j.issn.1000-3428.2011.24.094Aiming at the poor robustness problem of the binary hash for the audio fingerprint matching technology, this paper proposes a Parzen Gaussian kernel quantum hash scheme, which encodes the intermediate hash difference between two audio contents into an integer at a suitable range according to its probability density function, and characters the probability distribution of distribution. Experimental results show that the method is more robust under various distortions than the binary hash.
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Computer Engineering. 2011, 37(24): 284-286. https://doi.org/10.3969/j.issn.1000-3428.2011.24.095This paper presents a hybrid Cache coherence protocol suitable for multi-core environment. It uses the hybrid value propagation police, introduces a small capacity directory, D-Cache. The protocol overcomes the shortcoming of traditional coherence protocol that data request is undifferentiated broadcasted. It extends data block state so that eliminates ping-pang phenomenon. Simulation experimental results show that the protocol reduces test workload runtime and L1 Cache miss rate, improves the system performance.
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Computer Engineering. 2011, 37(24): 287-289. https://doi.org/10.3969/j.issn.1000-3428.2011.24.096This paper proposes a Radio Frequency Identification(RFID) anti-collision algorithm based on Adaptive Splitting Tree(AST). The algorithm estimates the size of the collision set and adaptively adjusts the splitting scale. RFID Tags can be evenly and fast divided into different subsets. Simulation results show that the algorithm can effectively reduce the amount of collision slots and idle slots. It shows good system efficiency even in situation with high tags population.
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Computer Engineering. 2011, 37(24): 290-292. https://doi.org/10.3969/j.issn.1000-3428.2011.24.097An adaptive software architecture with dynamic reconfiguration is proposed for members of distributed interactive simulation, and an adaptive software for general torpedo simulator is developed with the architecture. The adaptive software architecture is presented, which consists of four layers of interface communication, requirement management, adaptive reconfiguration, and function realization. The key techniques in software development are given, including adaptive reconfiguration engine, configurable component model, and function components set. An application case is carried out with the developed software and the results verify the feasibility and effectiveness.
2024
Volume 50 No 3
Volume 50 No 3
(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