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X-RESTORE: Middleware for XML's Relational Storage and Retrieve 被引量:4
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作者 Wan Chang-xuan +1 位作者 Liu Yun-Sheng 《Wuhan University Journal of Natural Sciences》 CAS 2003年第01A期28-34,共7页
We propose a new approach to store and query XML data in an RDBMS basing on the idea of the numbering scheme and inverted list. O ur approach allows us to quickly determine the precedence, sibling and ancestor/ desc... We propose a new approach to store and query XML data in an RDBMS basing on the idea of the numbering scheme and inverted list. O ur approach allows us to quickly determine the precedence, sibling and ancestor/ descendant relationships between any pair of nodes in the hierarchy of XML, and utilize path index to speed up calculating of path expressions. Examples have de monstrated that our approach can effectively and efficiently support both XQuery queries and keyword searches. Our approach is also flexible enough to support X ML documents both with Schema and without Schema, and applications both retrieva l and update. We also present the architecture of middleware for application acc essing XML documents stored in relations, and an algorithm translating a given X ML document into relations effectively. 展开更多
关键词 XML retrieve keyword search relational storage numbering scheme
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Fast Computation of Sparse Data Cubes with Constraints 被引量:2
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作者 FengYu-cai ChenChang-qing FengJian-lin XiangLong-gang 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第2期167-172,共6页
For a data cube there are always constraints between dimensions or among attributes in a dimension, such as functional dependencies. We introduce the problem that when there are functional dependencies, how to use the... For a data cube there are always constraints between dimensions or among attributes in a dimension, such as functional dependencies. We introduce the problem that when there are functional dependencies, how to use them to speed up the computation of sparse data cubes. A new algorithm CFD (Computation by Functional Dependencies) is presented to satisfy this demand. CFD determines the order of dimensions by considering cardinalities of dimensions and functional dependencies between dimensions together, thus reduce the number of partitions for such dimensions. CFD also combines partitioning from bottom to up and aggregate computation from top to bottom to speed up the computation further. CFD can efficiently compute a data cube with hierarchies in a dimension from the smallest granularity to the coarsest one. Key words sparse data cube - functional dependency - dimension - partition - CFD CLC number TP 311 Foundation item: Supported by the E-Government Project of the Ministry of Science and Technology of China (2001BA110B01)Biography: Feng Yu-cai (1945-), male, Professor, research direction: database system. 展开更多
关键词 sparse data cube functional dependency DIMENSION PARTITION CFD
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A novel face recognition method with feature combination 被引量:2
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作者 李文书 周昌乐 许家佗 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第5期454-459,共6页
A novel combined personalized feature framework is proposed for face recognition (FR). In the framework, the proposed linear discriminant analysis (LDA) makes use of the null space of the within-class scatter matrix e... A novel combined personalized feature framework is proposed for face recognition (FR). In the framework, the proposed linear discriminant analysis (LDA) makes use of the null space of the within-class scatter matrix effectively, and Global feature vectors (PCA-transformed) and local feature vectors (Gabor wavelet-transformed) are integrated by complex vectors as input feature of improved LDA. The proposed method is compared to other commonly used FR methods on two face databases (ORL and UMIST). Results demonstrated that the performance of the proposed method is superior to that of traditional FR ap- proaches 展开更多
关键词 Fisher discriminant criterion Face recognition (FR) Linear discriminant analysis (LDA) Principal component analysis (PCA) Small sample size (SSS)
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Summarization based on physical features and logical structure of multi documents 被引量:2
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作者 秦兵 LiuTing LiSheng 《High Technology Letters》 EI CAS 2005年第2期133-136,共4页
With the rapid development of the Internet, multi documents summarization is becoming a very hot research topic. In order to generate a summarization that can effectively characterize the original information from doc... With the rapid development of the Internet, multi documents summarization is becoming a very hot research topic. In order to generate a summarization that can effectively characterize the original information from documents, this paper proposes a multi documents summarization approach based on the physical features and logical structure of the document set. This method firstly clusterssimilar sentences into several Logical Topics (LTs), and then orders these topics according to their physical features of multi documents. After that, sentences used for the summarization are extracted from these LTs, and finally the summarization is generated via certain sorting algorithms. Our experiments show that the information coverage rate of our method is 8.83% higher than those methods based solely on logical structures, and 14.31% higher than Top-N method. 展开更多
关键词 因特网 多文件摘要 逻辑结构 拓扑结构 物理特征
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Combined Viterbi Detector for a Balanced Code in Page Memories 被引量:1
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作者 ChenDuan-rong XieChang-sheng1 PeiXian-deng 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第1期37-40,共4页
Based on the two path metrics being equal at a merged node in the trellis employed to describe a Viterbi detector for the detection of data encoded with a rate 6:8 balanced binary code in page-oriented optical memorie... Based on the two path metrics being equal at a merged node in the trellis employed to describe a Viterbi detector for the detection of data encoded with a rate 6:8 balanced binary code in page-oriented optical memories, the combined Viterbi detector scheme is proposed to improve raw biterror rate performance by mitigating the occurrence of a twobit reversing error event in an estimated codeword for the balanced code. The effectiveness of the detection scheme is verified for different data quantizations using Monte Carlo simulations. Key words holographic data storage - balanced code - modulation code - Viterbi algorithm - path metric CLC number TN 911. 21 Foundation item: Supported by National 973 Research Program of China (G1999033006)Biography: Chen Duan-rong (1960-), male, Lecturer, Ph. D candidate, research direction: coding and signal processing for the recording channel of holographic data storage. 展开更多
关键词 holographic data storage balanced code modulation code Viterbi algorithm path metric
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A Hybrid Approach for Selection in Service Community 被引量:1
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作者 TANG Chaogang 《China Communications》 SCIE CSCD 2014年第A01期114-120,共7页
Although there have been existing competitions among web service (WS) providers, they still have opportunities to cooperate together for common profits. WS community as a mean to provide an ontological organizati... Although there have been existing competitions among web service (WS) providers, they still have opportunities to cooperate together for common profits. WS community as a mean to provide an ontological organization of WSs that share the same domain of interest has realized this kind of fancy in the sense that providers can work together to compete against others outside the community. Service selection in WS community is different from the traditional service selection, since WS community should take into account its own benefits. Therefore, we propose a hybrid approach to make service selection in WS community. The approach considers the profits of both WS community and the services within it. The experimental evaluation shows that the approach has a great advantage over other approach without consideration of community's benefits. 展开更多
关键词 COMMUNITY service selection PROFITS dominating TOP-K
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Design and Implementation of Web Services Security Based on Message Layer 被引量:1
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作者 WANGCui-ru XUZheng-wei YUANHe-jin MAHui-min 《Wuhan University Journal of Natural Sciences》 CAS 2004年第5期755-759,共5页
Along with the development of Internet, Web Services technology is a new branch of Web application program, and it has become a hotspot in computer science. However, it has not made great progress in research on Web S... Along with the development of Internet, Web Services technology is a new branch of Web application program, and it has become a hotspot in computer science. However, it has not made great progress in research on Web Services security. Traditional security solutions cannot satisfy the Web Services security require of selective protection, end-to-end security and application layer security. Web Services technology needs a solution integrated in Web Services framework to realize end-to-end security. Based on cryptography and Web Services technology and according to W3C, XML encryption specification, XML digital Signature specification and WS-Security, which proposed by IBM and Microsoft, a new Web services security model based on message layer is put forward in this paper. The message layer is composed of message handlers. It is inserted into the message processing sequence and provides transparent security services for Web Services. To verify the model, a Web Services security system is realized on, net platform. The implementation version of the model can provide various security services, and has advantages such as security, scalability, security controllability and end-to-end security in message level. Key words Web services - Web services security - message layer CLC number TP 393.08 Biography: WANG Cui-ru (1954-), female, Professor, research direction: database and information management system. 展开更多
关键词 Web services Web services security message layer
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Data Hiding and Security for XMLDatabase: A TRBAC-Based Approach 被引量:1
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作者 ZHANGWan-song SUNWei LIUDa-xin 《Wuhan University Journal of Natural Sciences》 CAS 2005年第1期293-296,共4页
In order to cope with varying protection granularity levels of XML(extensible Markup Language) documents, we propose a TXAC (Two-level XML. Access Control) framework,in which an extended TRBAC ( Temporal Role-Based Ac... In order to cope with varying protection granularity levels of XML(extensible Markup Language) documents, we propose a TXAC (Two-level XML. Access Control) framework,in which an extended TRBAC ( Temporal Role-Based Access Control) approach is proposed to deal withthe dynamic XML data With different system components, LXAC algorithm evaluates access requestsefficiently by appropriate access control policy in dynamic web environment. The method is aflexible and powerful security system offering amulti-level access control solution. 展开更多
关键词 XML data access control data security
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Design Pattern Mining Using Graph Matching 被引量:1
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作者 LIQing-hua ZHANGZhi-xiang BENKe-rong 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第4期444-448,共5页
The identification of design pattern instances is important for program understanding and software maintenance. Aiming at the mining of design patterns in existing systems, this paper proposes a subgraph isomorphism a... The identification of design pattern instances is important for program understanding and software maintenance. Aiming at the mining of design patterns in existing systems, this paper proposes a subgraph isomorphism approach to discover several design patterns in a legacy system at a time. The attributed relational graph is used to describe design patterns and legacy systems. The sub-graph isomorphism approach consists of decomposition and composition process. During the decomposition process, graphs corresponding to the design patterns are decomposed into sub-graphs, some of which are graphs corresponding to the elemental design patterns. The composition process tries to get sub-graph isomorphism of the matched graph if sub-graph isomorphism of each subgraph is obtained. Due to the common structures between design patterns, the proposed approach can reduce the matching times of entities and relations. Compared with the existing methods, the proposed algorithm is not linearly dependent on the number of design pattern graphs. Key words design pattern mining - attributed relational graph - subgraph isomorphism CLC number TP 311.5 Foundation item: Supported by the National Natural Science Foundation of China (60273075) and the Science Foundation of Naval University of Engineering (HGDJJ03019)Biography: LI Qing-hua (1940-), male, Professor, research direction: parallel computing. 展开更多
关键词 design pattern mining attributed relational graph subgraph isomorphism
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Lattice—BGK simulation of a two—dimensional channel flow around a square cylinder 被引量:9
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作者 郭卫斌 王能超 《Chinese Physics B》 SCIE EI CAS CSCD 2003年第1期67-74,共8页
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Adaptive tracking controller using BP neural networks for a class of nonlinear systems 被引量:5
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作者 LiuZilong LiuGuozhong LiuJie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第4期598-604,共7页
An BP neural-network-based adaptive control (NNAC) design method is described whose aim is to control a class of partially unknown nonlinear systems. Making use of the online identification of BP neural networks, the ... An BP neural-network-based adaptive control (NNAC) design method is described whose aim is to control a class of partially unknown nonlinear systems. Making use of the online identification of BP neural networks, the results of the identification could be used into the parameters of the controller. Not only the strong robustness with respect to uncertain dynamics and nonlinearities can be obtained, but also the output tracking error between the plant output and the desired reference output can asymptotically converge to zero by Lyapunov theory in the process of this design method. And a simulation example is also presented to evaluate the effectiveness of the design. 展开更多
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A unified incompressible lattice BGK model and its application to three-dimensional lid-driven cavity flow 被引量:3
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作者 何南忠 王能超 +1 位作者 施保昌 郭照立 《Chinese Physics B》 SCIE EI CAS CSCD 2004年第1期40-46,共7页
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The Response Time Analysis of Digital Broadcasting System
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作者 WANGShuo ZHANGJiang-ling FENGDan 《Wuhan University Journal of Natural Sciences》 CAS 2005年第3期515-519,共5页
Digital broadcasting system has become a high-light of research on computer application. To respond to the changes of the playbill in the broadcasting system in real time, the response time of the system must be studi... Digital broadcasting system has become a high-light of research on computer application. To respond to the changes of the playbill in the broadcasting system in real time, the response time of the system must be studied. There is scarcely the research on this area currently. The influence factors in the response time are analyzed; the model on the response time of the system service is built; how the influence factors affect the response time of the system service is validated; and four improvement measures are proposed to minimize the response time of system service. 展开更多
关键词 Key words digital broadcasting system response time ANALYSIS REAL TIME
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A High-Speed Information Retrieval System
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作者 SHIShu-dong LIZhi-tang 《Wuhan University Journal of Natural Sciences》 CAS 2004年第4期425-428,共4页
We cleveloped a high-speed information retrieval system. The system hased on the IXP 2800 is one of the dedicute device. The velocity of the information retrieval is 6.8 Gb/s. The protocol support Telnet, FTP, SMTP, P... We cleveloped a high-speed information retrieval system. The system hased on the IXP 2800 is one of the dedicute device. The velocity of the information retrieval is 6.8 Gb/s. The protocol support Telnet, FTP, SMTP, POP3 etc. various networks protocols. The information retrieval supports the key word and the natural language process. This paper explains the hardware system, software system and the index of the performance. Key words network processor - IXP2800 - information retrieval - IXA CLC number TP 309 Foundation item: Supported by the National Natural Science Foundation of China (69873016 & 69972017) and the National High Technology Development Program of China (863-301-06-1)Biography: SHI Shu-dong (1963-), male, Ph. D. candidate, research direction: network & information security. 展开更多
关键词 network processor IXP2800 information retrieval IXA
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Ontology Based Resolution of Semantic Conflicts in Information Integration
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作者 LUHan LIQing-zhong 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期606-610,共5页
Semantic conflict is the conflict caused by using different ways in heterogeneous systems to express the same entity in reality. This prevents information integration from accomplishing semantic coherence. Since ontol... Semantic conflict is the conflict caused by using different ways in heterogeneous systems to express the same entity in reality. This prevents information integration from accomplishing semantic coherence. Since ontology helps to solve semantic problems, this area has become a hot topic in information integration. In this paper, we introduce semantic conflict into information integration of heterogeneous applications. We discuss the origins and categories of the conflict, and present an ontology-based schema mapping approach to eliminate semantic conflicts. Key words ontology - CCSOL - semantic conflict - schema mapping CLC number TP 301 Biography: LU Han (1980-), male, Master candidate, research direction: ontology and information integration. 展开更多
关键词 ONTOLOGY CCSOL semantic conflict schema mapping
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Approach in High Precision Topic-Specific Resource Discovery on the Web
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作者 YeWei-guo LuZheng-ding 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第1期41-45,共5页
The Internet presents numerous sources of useful information nowadays. However, these resources are drowning under the dynamic Web, so accurate finding user-specific information is very difficult. In this paper we dis... The Internet presents numerous sources of useful information nowadays. However, these resources are drowning under the dynamic Web, so accurate finding user-specific information is very difficult. In this paper we discuss a Semantic Graph Web Search (SGWS) algorithm in topic-specific resource discovery on the Web. This method combines the use of hyperlinks, characteristics of Web graph and semantic term weights. We implement the algorithm to find Chinese medical information from the Internet. Our study showed that it has better precision than traditional IR (Information Retrieval) methods and traditional search engines. Key words HITS - evolution web graph - power law distribution - context analysis CLC number TP 391 - TP 393 Foundation item: Supported by the National High-Performance Computation Fund (00303)Biography: Ye Wei-guo (1970-), male, Ph. D candidate, research direction: Web information mining, network security, artificial intelligence. 展开更多
关键词 HITS evolution web graph power law distribution context analysis
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A Dynamic XML-NS View Based Approach for the Extensible Integration of Web Data Sources
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作者 WUWei LUZheng-ding LIRui-xuan WANGZhi-gang 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期647-651,共5页
We propose a three-step technique to achieve this purpose. First, we utilize a collection of XML namespaces organized into hierarchical structure as a medium for expressing data semantics. Second, we define the format... We propose a three-step technique to achieve this purpose. First, we utilize a collection of XML namespaces organized into hierarchical structure as a medium for expressing data semantics. Second, we define the format of resource descriptor for the information source discovery scheme so that we can dynamically register and/or deregister the Web data sources on the fly. Third, we employ an inverted-index mechanism to identify the subset of information sources that are relevant to a particular user query. We describe the design, architecture, and implementation of our approach—IWDS, and illustrate its use through case examples. Key words integration - heterogeneity - Web data source - XML namespace CLC number TP 311.13 Foundation item: Supported by the National Key Technologies R&D Program of China(2002BA103A04)Biography: WU Wei (1975-), male, Ph.D candidate, research direction: information integration, distribute computing 展开更多
关键词 INTEGRATION HETEROGENEITY Web data source XML namespace
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A New Local Search Algorithm for the Job Shop Scheduling Problem
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作者 HuangWen-qi YinAi-hua 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03A期797-802,共6页
In this paper, the job shop scheduling problem concerned with minimizing make\|span is discussed, and a new local search algorithm is proposed for it. This local search method is based on an improved shifting bottlene... In this paper, the job shop scheduling problem concerned with minimizing make\|span is discussed, and a new local search algorithm is proposed for it. This local search method is based on an improved shifting bottleneck procedure and Tabu Search technique. This new local search is different from the previous Tabu Search (TS) proposed by other authors, which is because the improved shifting bottleneck procedure is a new technology that is provided by us for the problem, and two remarkable strategies--intensification and diversification of TS are modified. To demonstrate the performance, our algorithm has been tested on many common problem instances (benchmarks) with various sizes and levels of hardness and compared with other algorithms, especially the latest TS in the literatures. Computational experiments show that this algorithm is effective and efficient. 展开更多
关键词 HEURISTIC improved shifting bottleneck procedure Tabu search INTENSIFICATION DIVERSIFICATION
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Reliable routing algorithm in marine ad hoc networks
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作者 LINWei YANGYong-Tian 《Journal of Marine Science and Application》 2004年第2期46-49,共4页
A routing algorithm called DNH for increasing efficiency of mobile ad hoc network is presented, which is based on a new criterion called TSS ( Temporarily Steady State) , combining with wireless transmission theory th... A routing algorithm called DNH for increasing efficiency of mobile ad hoc network is presented, which is based on a new criterion called TSS ( Temporarily Steady State) , combining with wireless transmission theory that makes networks topology correspondingly stabilization. Also the DNH algorithm has the characteristics of giving up queuing in a node, but selecting another idle node instead of the node for forwarding data packets if the node has a full throughput. Simulation evaluation shows that selecting another node is better than queuing in a full throughout node if some conditions are satisfied, especially during a sea battle, every warship in ad hoc network wants to contest time and increase propagation reliability. The DNH algorithm can help decrease routing time, and raise efficiency of marine ad hoc networks. 展开更多
关键词 船舶 ADHOC网络 布线协议 DNH
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Data Mining Based on Computational Intelligence
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作者 WANGYuan-zhen ZHANGZhi-bing +1 位作者 YIBao-lin LIHua-yang 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第2期371-374,共4页
This paper combines computational intelligence tools: neural network, fuzzylogic, and genetic algorithm to develop a data mining architecture (NFGDM), which discovers patternsand represents them in understandable form... This paper combines computational intelligence tools: neural network, fuzzylogic, and genetic algorithm to develop a data mining architecture (NFGDM), which discovers patternsand represents them in understandable forms. In the NFGDM, input data arepreprocesscd byfuzzification, the preprocessed data of input variables arc then used to train a radial basisprobabilistic neural network to classify the dataset according to the classes considered, A ruleextraction technique is then applied in order to extract explicit knowledge from the trained neuralnetworks and represent it m the form of fuzzy if-then rules. In the final stage, genetic algorithmis used as a rule-pruning module to eliminate those weak rules that are still in the rule bases.Comparison with some known neural network classifier, the architecture has fast learning speed, andit is characterized by the incorporation of the possibility information into the consequents ofclassification rules in human understandable forms. The experiments show that the NFGDM is moreefficient and more robust than traditional decision tree method. 展开更多
关键词 data mining rule extraction neural network fuzzy logic genetic algorithm
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