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A Hybrid Genetic Algorithm for Reduct of Attributes in Decision System Based on Rough Set Theory

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wuhan University Journal of Natural Sciences 2002年第3期7卷 285-289页

作者： Dai Jian\|hua 1,2., Li Yuan\|xiang 1,2.,Liu Qun 3.1. state {3. {2. of software {3., wuhan University, wuhan 43.072. hubei,China 2. School of Computer, wuhan University, wuhan 43.072. hubei, China 3. School of Computer Science, wuhan University State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan University School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Chongqing University of Posts & Telecommunications School of Computer Science Chongqing China (GRID:grid.411587.e) (ISNI:***)

Knowledge reduction is an important issue when dealing with huge amounts of data. And it has been proved that computing the minimal reduct of decision system is NP-complete. By introducing heuristic information into genetic algorithm, we proposed a heuristic genetic algorithm. In the genetic algorithm, we constructed a new operator to maintaining the classification ability. The experiment shows that our algorithm is efficient and effective for minimal reduct, even for the special example that the simple heuristic algorithm can’t get the right result.

关键词： rough set reduction genetic algorithm heuristic algorithm

A hybrid matching method for geospatial services in a composition-oriented environment

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Science China(Technological Sciences) 2010年第S1期53卷 213-220页

作者： LUO An 1,2.WANG YanDong 1,2.& CHEN ShengHua 2.1 {3. key {2. of software {3.,wuhan University,wuhan 43.072.China 2.{3. key {2. of Information {3. in Surveying,Mapping and Remote Sensing,wuhan University,wuhan 43.079,China 1. state key {2. of {3. {3. Wuhan University Wuhan 430072 China 2. state key {2. of Information engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China

With the development of Internet and GIS,large volumes of spatial data,powerful computing resources and many spatial data processing functions are published in the form of Web *** suitable geospatial services in the composition-oriented environment is a crucial *** semantic Web provides a kind of technology to find and compose various service resources automatically through the *** paper proposes a hybrid method for the semantic matching of geospatial *** method includes two *** 1 puts forward a multi-level semantic matching approach,which matches single geospatial service at four levels:classification,input/output,precondition/effect and the quality of service(QoS).This multi-level matching approach makes single service matching quicker and more *** 2.puts forward a matching algorithm for a geospatial service chain based on the *** algorithm adopts a trace algorithm,taking account of the effect of the *** restricts the input/output parameters of the current service by the input/output parameters of service chain,pre-service and *** matches the atomic service dynamically in a composition-oriented environment,and accurately converts the abstract model of geospatial services into an executable geospatial service chain.A case study of the flood analysis for the Poyang Lake illustrates the effectiveness of our context-based matching method for geospatial services.

关键词： geospatial services semantic context composition service match

Genetic Algorithm for Chinese Postman Problems

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wuhan University Journal of Natural Sciences 2003年第S1期8卷 316-318页

作者： Jiang Hua, Kang Li-shanstate key {2. of {3. {3., wuhan University,wuhan 43.072.hubei, China wuhan University State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

Chinese Postman Problem is an unsettled graphic problem. It was approached seldom by evolutionary computation. Now we use genetic algorithm to solve Chinese Postman Problem in undirected graph and get good results. It could be extended to solve Chinese postman problem in directed graph. We make these efforts for exploring in optimizing the mixed Chinese postman problem.

关键词： Chinese postman problem Eularian graph genetic algorithm evolutionary computation

Building Distributed Web GIS: A Mobile Agent Based Approach

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wuhan University Journal of Natural Sciences 2001年第Z1期6卷 474-481页

作者： jhguan@*** Guan Ji hong 1 , Zhou Shui geng 2., Bian Fu ling 3. Meng Ling kui 3.1. School of Computer, wuhan University, wuhan {2. China {3., wuhan University, wuhan {2. Chin School of Computer Wuhan University Wuhan 430072 China

The diversity of GISs and the wide spread availability of WWW have led to an increasing amount of research on integrating a variety of heterogeneous and autonomous GISs in a cooperative environment to construct a new generation of GIS characterizing in open architecture, distributed computation, interoperability, and extensibility. Our on going research project MADGIS (Mobile Agent based Distributed Geographic Information System) is reported, in which we propose the architecture of MADGIS to meet the requirements of integrating distributed GIS applications under Internet environment. We first describe the architecture of MADGIS, and detailed discussions focusing on the structure of client site, server site and mobile agent in MADGIS. Then we explore key techniques for MADGIS implementation.

关键词： distributed GIS mobile agent architecture mobility interoperability

Extended multivariate public key cryptosystems with secure encryption function

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Science China(Information Sciences) 2011年第6期54卷 1161-1171页

作者： WANG HouZhen 1,2., ZHANG HuanGuo 1,2., WANG ZhangYi 1,2.& TANG Ming 1,2.1 The key laboratory of Aerospace Information Security and Trusted Computing, Ministry of Education, School of Computer, {2. University, {2. 43.079, China 2.{3. key laboratory of software {13., {2. University, {2. 43.072. China 1. The key laboratory of Aerospace Information Security and Trusted Computing Ministry of Education School of Computer Wuhan University Wuhan 430079 China2. State Key Laboratory of Software Engineering Wuhan University Wuhan 430072 China

Advances in quantum computers pose great threats on the currently used public key cryptographic algorithms such as RSA and ECC. As a promising candidate secure against attackers equipped with quantum computational power, multivariate public key cryptosystems (MPKCs) have attracted increasing attention in recently years. Unfortunately, the existing MPKCs can only be used as a multivariate signature scheme, and it remains unknown how to construct an efficient MPKC enabling secure encryption. Furthermore, some multivariate signature schemes have been shown insecure in recent years, and it is also not trivial to build MPKC which can serve as a secure signature scheme. By employing the basic MQ-trapdoors, this paper proposes a novel MPKC and shows how it can be used as a multivariate signature scheme and a multivariate encryption scheme, respectively. The goal is achieved by incorporating our new hash authentication techniques and some modification methods such as the Shamir's minus method. Thorough analysis shows that our schemes are secure and efficient. Our MPKC gives a positive response to the challenges in multivariate public key cryptography.

关键词： cryptography post-quantum cryptography MQ problem hash function

A Feedback-Based Web Search Engine

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wuhan University Journal of Natural Sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2.3., XU Bao-wen 2.3.4 , ZHOU Xiao-yu 2.3.4 1. Department of Computer Science and {3., Nanjing University of Posts and Telecommunications, Nanjing 2.0003. Jiangsu, China 2. Department of Computer Science and {3., Southeast University, Nanjing 2.0096, Jiangsu, China 3. Jiangsu Institute of {2. Quality, Nanjing 2.0096 Jiangsu, China 4. The {3. key laboratory of {2. {3., wuhan University, wuhan 43.072. hubei, China Department of Computer Science and engineering Nanjing University of Posts and Telecommunications . Nanjing 210003 Jiangsu China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. key words WWW - search engine - query reconstruction - feedback CLC number TP 3.1. 13..4 Foundation item: Supported by the National Natural Science Fundation of China (603.3.66). National Grand Fundamental Research 973.Program of China (2.02.B3.2.0). Opening Foundation of state key laboratory of software {3. in wuhan University, Opening Foundation of Jiangsu key laboratory of Computer Information Processing Technology in Soochow UniversityBiography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

Hierarchical Classification of Chinese Documents Based on N grams

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wuhan University Journal of Natural Sciences 2001年第Z1期6卷 416-422页

作者： Zhou Shui geng 1, Guan Ji hong 2. He Yan xiang 2.1. state {3. {2. of software {3., wuhan University, wuhan 43.072. China 2. School of Computer Science, wuhan University, wuhan 43.072. China state key {2. of {3. {3. Wuhan University Wuhan China School of Computer Science Wuhan University Wuhan China

We explore the techniques of utilizing N gram information to categorize Chinese text documents hierarchically so that the classifier can shake off the burden of large dictionaries and complex segmentation processing, and subsequently be domain and time independent. A hierarchical Chinese text classifier is implemented. Experimental results show that hierarchically classifying Chinese text documents based N grams can achieve satisfactory performance and outperforms the other traditional Chinese text classifiers.

关键词： Chinese text classification N grams feature selection hierarchical classification

An efficient method for detecting concurrency errors in object-oriented programs

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Science China(Information Sciences) 2012年第12期55卷 2774-2784页

作者： HE YanXiang 1,2.WU Wei 2.& CHEN Yong 2.1 School of Computers,{3. University,{3. {2.China 2.{3. key laboratory of software engineering,{3. University,{3. {2.China 1. School of Computers Wuhan University Wuhan 430072 China2. State Key Laboratory of Software Engineering Wuhan University Wuhan 430072 China

Multicore and multi-threaded processors have become the norm for modern ***,concurrent programs have become more and more prevalent despite being difficult to write and *** errors are highly likely to appear in concurrent code,conventional error detection methods such as model checking,theorem proving,and code analysis do not scale smoothly to concurrent *** is an indispensable technique for detecting concurrency errors,but it involves a great deal of manual work and is *** paper presents an automatic method for detecting concurrency errors in classes in object-oriented *** method uses a heuristic algorithm to automatically generate test cases that can effectively trigger ***,each test case is executed automatically and a fast method is adopted to identify the actual concurrency error from anomalous run *** have implemented a prototype of the method and applied it to some typical Java *** shows that our method is more effective and faster than previous work.

关键词： concurrency error dynamic test data race atomicity violations test case generation

HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

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Journal of Iron and Steel Research International 2012年第10期19卷 13-19页

作者： XIAO Xiao-feng1,2. YE Sheng-ping2. YIN Wei-xin3. XUE Qiong4 (1. School of Mechanical engineering and Automation, {3. Textile University, {3. 43.073. {3., China 2. state key laboratory of Material Processing and Die and Mould Technology, Huazhong University of Science and Technology, {3. 43.074, {3., China 3. {3. Zhike Abrasive-Resistant Material Science and Technology Development Co Ltd, {3. 43.073. {3., China 4. College of Science, {3. University of Technology, {3. 43.079, {3., China) [a] School of Mechanical engineering and Automation Wuhan Textile University Wuhan 430073 Hubei China [b] state key {2. of Material Processing and Die and Mould Technology Huazhong University of Science and Technology Wuhan 430074 Hubei China [c] wuhan Zhike Abrasive-Resistant Material Science and Technology Development Co Ltd Wuhan 430073 Hubei China [d] College of Science Wuhan University of Technology Wuhan 430079 Hubei China

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XRD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HRC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2.and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.

关键词： composite liner bimetal liquid-liquid compound composite interface lost foam casting high Cr white cast iron