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Evaluation Method of Web Site Structure Based on Web Structure Mining

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wuhan university Journal of Natural Sciences 2003年第3A期8卷 791-796页

作者： Li Jun\|e 1 , Zhou Dong\|ru 2.1. Computer Center,wuhan {2., wuhan 430072, Hubei, china 2. school of Computer,wuhan {2., wuhan 430072, Hubei,china Computer Center Wuhan University Wuhan Hubei China school of Computer Wuhan University Wuhan Hubei China

The structure of Web site became more complex than before. During the design period of a Web site, the lack of model and method results in improper Web structure, which depend on the designer's experience. From the point of view of software engineering, every period in the software life must be evaluated before starting the next period's work. It is very important and essential to search relevant methods for evaluating Web structure before the site is completed. In this work, after studying the related work about the Web structure mining and analyzing the major structure mining methods (Page\|rank and Hub/Authority), a method based on the Page\|rank for Web structure evaluation in design stage is proposed. A Web structure modeling language WSML is designed, and the implement strategies for evaluating system of the Web site structure are given out. Web structure mining has being used mainly in search engines before. It is the first time to employ the Web structure mining technology to evaluate a Web structure in the design period of a Web site. It contributes to the formalization of the design documents for Web site and the improving of software engineering for large scale Web site, and the evaluating system is a practical tool for Web site construction.

关键词： web structure mining page\|rank web structure evaluation modeling language for web structure

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,{2. university,wuhan 430072.china 2.State Key Laboratory of Software Engineering,{2. university,wuhan 430072.china school of Computers Wuhan University Wuhan China State Key Laboratory of Software Engineering Wuhan University Wuhan 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

Electronic Structure of Doped Trans-Polyacetylene

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wuhan university Journal of Natural Sciences 2002年第1期7卷 51-53页

作者： Ren Da-zhi 1,2. Zhuang Wei 2. Wang Jun 2.1. wuhan university Journals Press,wuhan 430072,Hubei,china 2. school of Physics and Technology, wuhan university, wuhan 430072,Hubei,china wuhan university Journals Press Wuhan Hubei China school of Physics and Technology Wuhan University Wuhan Hubei China

The behavior of electronic structures of doped trans-polyacetylene is revealed by a simple method. (C2.H2.)+n is used to simulate p-type doped trans-polyacetylene at various doping concentrations. The electronic structure is calculated, by CNDO/2.method. These calculations show that at low doping level, the decrease of electronic energy compensates the increase of elastic energy, thus the bond alternation exists, and the charge carriers are solitons. When doping level is high, the increase of elastic energy is larger than the decrease, of electronic energy, the bond alternation disappears, solitons no longer exist, and polyacetylene is in a metalic state.

关键词： trans polyacetylene CNDO/2 electronic structure doped

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 Key Laboratory of Software Engineering, wuhan university, wuhan 430072, china 2. school of Computer Science, wuhan university, wuhan 430072, china State Key Laboratory of Software Engineering 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

A PRICE-SETTING NEWSVENDOR MODEL UNDER CVAR DECISION CRITERION WITH EMERGENCY PROCUREMENT

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Journal of Systems Science and Systems Engineering 2010年第1期19卷 85-104页

作者： Minghui XU school of Economics and Management,wuhan {2.,wuhan 430072.china school of Economics and Management Wuhan University Wuhan China

In this paper, we consider a newsvendor model in which a risk-averse manager faces a stochastic price-dependent demand in either an additive or a multiplicative form. An emergency purchase option is allowed after the realization of demand to satisfy the units that are short. By adopting Conditional value-at-risk （CVaR） as the decision criterion, we aim to investigate the optimal pricing and ordering decisions, and the effects of parameter changes in such a setting. We provide sufficient conditions for the uniqueness of the optimal policy for both demand models. We perforl~, comparative statics analysis to show how the optimal pricing and ordering decision behaves when changing parameters. We also compare our results with those of the newsvendor with a general utility function and with CVaR criterion under lost sales assumption. Our key results include：（i） For both demand models, the optimal selling price is decreasing in risk aversion. Hence, the optimal price of a risk-averse newsvendor is not greater than the optimal price of a risk-neutral newsvendor. （it） In contrary to the lost sales case, for the multiplicative demand model, the optimal order quantity may not be monotonic in risk aversion. Consequently, the optimal risk-averse order quantity may be lower or higher than the optimal risk- neutral counterpart. （iii） For the additive model, the optimal order quantity is strictly increasing in the emergency purchase price, while for the multiplicative model the optimal order quantity has no such a monotonic property. Some numerical examples are conducted to verify our claims and gain more insights about the risk-averse decision-making behaviors.

关键词： Newsvendor model inventory pricing risk aversion conditional value-at-risk

Commission Strategy of the Auction House

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wuhan university Journal of Natural Sciences 2006年第3期11卷 507-510页

作者： WANG Yan~ 1,2.1. College of Economics, Fudan university, Shanghai 2.0433, china 2. {2. of Mathematics and Statistics, wuhan university , wuhan 430072, Hubei, china College of Economics Fudan University Shanghai China school of Mathematics and Statistics Wuhan University Wuhan Hubei China

In a SIPV model, when the commission proportion is not certain, but related with bargain price, generally, it is a linear function of the bargain price, this paper gives bidders＇ equilibrium bidding strategies in the first-and secondprice auctions. We find that the equilibrium strategies in second-price auction are dominant strategies. For seller or auction house, whether the fixed proportion or the unfixed proportion is good is not only related with constant item and the linear coefficient of the linear function, the size of the fixed commission proportion, but also related with the value of the item auctioned. So, in the practical auctions, the seller and the auction house negotiated with each other to decide the commission rules for their own advantage.

关键词： auction commission proportion Bayesian equilibrium bidding strategy

An Overview on Wavelet Software Packages

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wuhan university Journal of Natural Sciences 2001年第Z1期6卷 593-600页

作者： Fan Qi\|bin 1, Li Hong 2.1. school of Mathematics and Statistics, wuhan {2., wuhan 430072, china 2. school of Electronic Information, wuhan {2., wuhan 430072, china school of Mathematics and Statistics Wuhan University Wuhan China school of Electronic Information Wuhan University Wuhan China

Wavelet analysis provides very powerful problem\|solving tools for analyzing, encoding, compressing, reconstructing, and modeling signals and images. The amount of wavelets\|related software has been constantly multiplying. Many wavelet analysis tools are widely available. This overview represents a significant survey for many currently available packages. It will be of great benefit to engineers and researchers for using the toolkits and developing new software. The beginner to learning wavelets can also get a great help from the review. If you browse around at some of the Internet sites listed in the reference of this paper, you may find more plentiful wavelet resources.

关键词： wavelet transforms image compression matching pursuit lifting MATLAB

Fabrication of Dense Ultrafine TiAl Alloys by Spark Plasma Synthesis from Mechanically Activiated Powders

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Journal of wuhan university of Technology(Materials Science) 2007年第3期22卷 408-411页

作者：夏力 Department of Materials Engineering Wuhan University

Powder of Ti-46at%Al alloy was synthesized through mechanical activation（MA） and then sintered and concurrently consolidated in a short sintering time of 900 s by using a spark plasma sintering（SPS） process. The XRD and SEM profiles show that the microstructures of TiAl alloys contained γ TiAl and small amount α-2.Ti3Al phase, whose amount can be controlled by the sintering temperature. The compacts retained the original fine-grained fully densified bodies by avoiding an excessively high sintering temperature. The alloys sintered at higher temperature with this process showed a coarser microstructure. So it is possible to produce dense nanostructured TiAl alloys by mechanically activated spark plasma sintering （MASPS） within a very short period of time.

关键词： titanium aluminides mechanical activation spark plasma sintering (SPS)

Capability of evolutionary cryptosystems against differential cryptanalysis

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Science china(Information Sciences) 2011年第10期54卷 1991-2000页

作者： ZHANG HuanGuo 1,2.,LI ChunLei 1,2.& TANG Ming 1,2.1 school of Computer,{2. university,wuhan 430072.china 2.Key Laboratory of Aerospace Information Security and Trusted Computing of Ministry of Education,{2. university,wuhan 430072.china school of Computer Wuhan University Wuhan China Key Laboratory of Aerospace Information Security and Trusted Computing of Ministry of Education Wuhan University Wuhan China

The evolutionary cryptosystem is a new *** paper studies its security level resisting against differential *** is shown that the evolutionary cryptosystem possesses higher resistance than its initial fixed cryptosystem against differential *** the basis of the relationship among the data complexity,the bit advantage and the success rate of differential cryptanalysis,it is proven that more data is needed for attacking the evolutionary cryptosystem when the bit advantage and success rate are ***,it is shown that the time complexity for attacking the evolutionary cryptosystem is higher than that of differential attacking its initial fixed cryptosystem with the same amount of plaintext-ciphertext *** research indicates that the evolutionary cryptosystem is more robust than its initial fixed cryptosystem against differential cryptanalysis.

关键词： information security cryptology evolutionary cryptosystem cryptanalysis differential cryptanalysis