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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 {2.hubei,china 2. school of Physics and Technology, wuhan university, wuhan {2.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

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 4.0072. 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

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 Key Laboratory of Software Engineering, wuhan university, wuhan {2. hubei,china 2. school of computer, wuhan university, wuhan {2. hubei, china 3. school of {12. Science, Lab. of Software Eng. Wuhan Univ. Wuhan 430072 China Sch. of Comp. Wuhan Univ. Wuhan 430072 China Sch. of Comp. Sci. Chongqing Univ. of Post and Telecom. Chongqing 400065 China

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

Accountability Analysis of Electronic Commerce Protocols by Finite Automaton Model

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wuhan university Journal of Natural Sciences 2004年第3期9卷 293-295页

作者： Xie Xiao-yao 1,2., Zhang Huan-guo 1 1. school of computer, {2., wuhan 4.0072. hubei, china 2. Institute of Network Technology, Guizhou university of Technology, Guiyang 550003, Guizhou, china school of computer Wuhan University Wuhan Hubei China Institute of Network Technology Guizhou University of Technology Guiyang Guizhou China

The accountability of electronic commerce protocols is an important aspect to insures security of electronic transaction. This paper proposes to use Finite Automaton (FA) model as a new kind of framework to analyze the transaction protocols in the application of electronic commerce. Key words finite automaton - electronic commerce - nonrepudiation - information security CLC number TP 393. 08 Foundation item: Supported by the National Natural Science Foundation of china (66973034, 90104005, 60373087)Biography: Xie Xiao-yao (1952.), male, Professor, Ph. D candidate, research direction: information security.

关键词： finite automaton electronic commerce nonrepudiation information security

Effect of Substrate-Water Interaction on the Wetting Behavior in Water-Oil and Substrate-Water-Oil Systems

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wuhan university Journal of Natural Sciences 2003年第4A期8卷 1097-1102页

作者： Yuan Yin-quan 1,2., Zou Xian-wu 1 , Jin Zhun-zhi 1 1. school of Physics and Technology, wuhan university, {2. 4.0072. hubei, china 2. Department of Physics, Xiaogan university, Xiaogan 432.00, hubei, china school of Physics and Technology Wuhan University Wuhan Hubei China Department of Physics Xiaogan University Xiaogan Hubei China

The effects of the substrate-water interaction on the wetting behavior in water-oil and surfactant-water-oil systems confined by one substrate which has the preferential interaction to one species of particles have been investigated by using the free energy analysis and discontinuous molecular dynamic simulations. As the preferential interaction between the substrate and water particles varies from small repulsion to large attraction, the partial drying, partial wetting and complete wetting state are observed in sequence. In addition, the wetting behavior of surfactant aqueous solution on the substrate is not only dependent on the interaction, but also limited by the maximum equilibrium concentration of surfactants at the interface.

关键词： wetting behavior wetting transition preferential interaction substrate

Prediction of Tumor Outcome Based on Gene Expression Data

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wuhan university Journal of Natural Sciences 2004年第2期9卷 177-182页

作者： Liu Juan 1,2. Hitoshi Iba 3 1. school of computer, {2., wuhan 4.0072. hubei, china 2. State Key Laboratory of Software Engineering, wuhan 4.0072. hubei, china 3. Department of Frontier Informatics, university of Tokyo, Tokyo 113-8656, Japan school of computer Wuhan University Wuhan Hubei China State Key Laboratory of Software Engineering Wuhan Hubei China Department of Frontier Informatics University of Tokyo Tokyo Japan

Gene expression microarray data can be used to classify tumor types. We proposed a new procedure to classify human tumor samples based on microarray gene expressions by using a hybrid supervised learning method called MOEA+WV (Multi-Objective Evolutionary Algorithm+Weighted Voting). MOEA is used to search for a relatively few subsets of informative genes from the high-dimensional gene space, and WV is used as a classification tool. This new method has been applied to predicate the subtypes of lymphoma and outcomes of medulloblastoma. The results are relatively accurate and meaningful compared to those from other methods. Key words bioinformatics - tumor classification - Pareto optimization - MOEA CLC number Q 786 - TP 181 Foundation item: Supported by the National Natural Science Foundation of china (60301009), the Foundation of Young Scholars of Ministry of Education of china (150118) and Chenguang Project of {2. City (2.112.009).Biography: Liu Juan (1970-), female, Associate Professor, Postdoctoral, research direction: bioinformatics, data mining, machine learning.

关键词： bioinformatics tumor classification Pareto optimization MOEA

A Microenvironment, Rather than Chemical, Initiates the Cardiomyogenic Differentiation of Marrow Stromal Cells

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wuhan university Journal of Natural Sciences 2004年第4期9卷 513-521页

作者： LIU Wei-xin 1,2., SONG Jian 1 , WAN Yu 1, PAN Guo-dong 1 , LIU Yu 1 , CHENG Bang-chang 2.,CHEN Xi-chang 1 1. school of Medicine, wuhan university, {2. 430071, hubei, china 2. Renmin Hospital, wuhan university, {2. 430060, hubei, china Sch. of Medicine Wuhan Univ. Wuhan 430071 China Renmin Hospital Wuhan Univ. Wuhan 430060 China

To investigate the potential of cardiomyogenic differentiation of rat bone marrow stromal cells (MSCs), they were exposed to 5-azacytidine tretments (single/repeat) at varying concentrations (3, 5, 10 μmol/L) and the fates of the cells were analyzed by immunocytochemistry, Western blot and the reporter gene of enhanced cyan fluorescent protein (ECFP) under the control of ventricular myosin light chain 2.(MLC2.) promoter. MSCs were also cocultured with cardiomyocytes for periods up to 16 days, the expression of cardiac myosin heavy chain (MHC) and troponin I (Tn I) proteins was analyzed. After the induction with 5-azacytidine, neither spontaneously beating cells nor myotubes were found; MHC and Tn I proteins were also undetectable and no ECFP-positive MSCs were detected. But when cocultured with cardiomyocytes, spontaneously contracting MSCs were observed and cardiac specific proteins could be detected. The results proved that the novel effects of 5-azacytidine on the cardiomyogenic differentiation of MSCs should be questioned and a direct intercellular communication with cardiomyocytes is necessary for MSCs to differentiate into cardiomyocytes. Key words cardiomyocyte - cell differentiation - stem cell CLC number Q 813.5 - R 542.2.2.Foundation item: Supported by the Natural Science Foundation of hubei Province (2.02.B00150)Biography: LIU Wei-xin (1976-), male, Ph. D candidate, research direction: stem cell and cellular biology.

关键词： cardiomyocyte cell differentiation stem cell

Singular Integral Equations with Cosecant Kernel in Solutions with Singularities of High Order

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wuhan university Journal of Natural Sciences 2005年第2期10卷 339-343页

作者： HAN Hui-li 1,2.,DU Jin-yuan 1,3 1. school of Mathematics and Statistics, wuhan university, {2. 4.0072. hubei, china 2. school of Mathematics and computer, Ningxia university, Yinchuan 75002., Ningxia, china 3. Department of Mathematics, hubei Institute for Nationalities, Enshi 445000, hubei, china school of Mathematics and Statistics Wuhan University Wuhan Hubei China school of Mathematics and computer Ningxia University Yinchuan Ningxia China Department of Mathematies Hubei Institute for Nationalities Enshi Hubei China

We have discussed and solved the boundary value problem with period 2.π and the singular integral equation with kernel csc t-tv/a in solution having singularities of high order, where the smooth contour of integratio... 详细信息

关键词： boundary value problem singular integral equation the singularities of high order

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 {2. china 2. school of computer Science, wuhan university, wuhan {2. 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