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Journal of Hydrodynamics 2009年第6期21卷 779-789页

作者： SHI Liang-sheng YANG Jin-zhong state key {2. of Water Resources and Hydropower engineering Science Wuhan University Wuhan 430072 China The Sonny Astani Department of Civil and Environmental engineering University of Southern California Los Angeles CA 90089 USA

The sparse grid collocation method is discussed to qualify the uncertainty of solute transport. The Karhunen-Loeve （KL） expansion is employed to decompose the log transformed hydraulic conductivity. The head, velocity and concentration fields are represented by the Lagrange polynomial expansion. A sparse grid collocation method is then used to reduce the original stochastic partial differential equations to a set of deterministic equations which is collocated at selected interpolation （collocation） points. The collocation points are constructed by the Smolyak algorithm. The accuracy, efficiency and convergence property of sparse grid collocation method are investigated by numerical experiments. The analysis shows that stochastic collocation strategy helps to decouple stochastic computations, and all the numerical computation is possible to be implemented by existing deterministic finite element codes. The proposed method provides an efficient way to evaluate the uncertainty of the solute transport in the heterogeneous media.

关键词： stochastic partial differential equations collocation method solute transport uncertainty

SIMULATION OF SEDIMENT DEPOSITION IN A CAVITY WITH FREE SURFACE

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Journal of Hydrodynamics 2010年第5期22卷 626-633页

作者： ZHANG Xiao-feng CUI Zhan-feng LU Xin-hua state key {2. of Water Resource and Hydropower engineering Science Wuhan University Wuhan 430072 China Yangtze River Scientific Research Institute Wuhan 430010 China

Studies of the flow and sediment movement in a cavity with free surface were mostly limited to physical modeling experiments. In this study, the sediment movement is characterized in detail using a 3-D turbulent numerical model. To close the Reynolds equations, the standard k-ε model is employed. The VOF method is adopted to capture the time varying free surface and the porosity method is introduced to deal with the irregular boundary and the varying bed deformation. The computation results agree well with the experimental data in major aspects such as the vertical distribution of the sediment concentration and the deposition topography in the cavity. The comparisons show that this model can well predict the flow structure and the sediment movement and also the river bed deformation in a cavity.

关键词： 3-D turbulent flow cavity flow free surface VOF porosity sediment transport

Hemoglobin-biocatalyzed Synthesis of Conducting Molecular Complex of Polyaniline and Lignosulfonate

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Journal of wuhan University of Technology(Materials Science) 2008年第6期23卷 809-815页

作者：胡兴邹国林 Department of Bioengineering Huaihua University state key {2. of Virology College of Life SciencesWuhan University

A new biocatalyst route for the synthesis of a conducting polyaniline （PANI）/ lignosulfonate （LGS） complex was *** different catalysts such as hemoglobin （Hb）,5,10,15,2.-tetrakis （meso-hydroxyphenyl） porphyrin,iron （II） tetrasulfophthalocyanine and ferric chloride were used to polymerize aniline in the presence of a natural polyelectrolytes template *** experimental results show that Hb is an effective catalyst in this case and the synthesis is simple,and the conditions are mild in that the polymerization may be carried out in lower pH （1.0-4.0） buffered solution and optimal pH of *** concentrations of aniline,LGS and H2.2.in feed the favorable conditions for the production of PANI were ***-vis absorption,FTIR,elemental analysis,conductivity,cyclic voltammetry and thermogravimetric analyses confirm the formation of thermally stable and electroactive PANI.

关键词： hemoglobin polyaniline biocatalyst conductivity lignosulfonate

Electronic Structures and Bonding Properties of Ti_2.lC and Ti_3AlC_2

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Journal of wuhan University of Technology(Materials Science) 2007年第1期22卷 27-30页

作者：闵新民 Department of Applied Chemistry School of Science Wuhan University of Technology state key {2. of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

The relation among electronic structure, chemical bond and property of Ti2.lC, Ti3AlC2.and doping Si into Ti2.lC was studied by density function and the discrete variation （DFT-DVM） method. After adding Si into Ti2.lC, the interaction between Si and Ti is weaker than that between Al and Ti, and the strengths of ionic and covalent bonds decrease both. The ionic and covalent bonds in Ti3AlC2. especially in Ti-Al, are stronger than those in Ti2.lC. Therefore, in synthesis of Ti2.lC, the addition of Si enhances the Ti3AlC2.content instead of Ti2.lC. The density of state （DOS） shows that there is mixed conductor characteristic in Ti2.lC and Ti3AlC2. The DOS of Ti3AlC2.is much like that of Ti2.lC. Ti2.iAl1-xC has more obvious tendency to form a semiconductor than Ti2.lC, which is seen from the obvious difference of partial DOS between Si and Al 3/7.

关键词： Ti2.lC Ti3SiC2 doping electronic structure chemical bond

Object-level change detection based on full-scale image segmentation and its application to Wenchuan Earthquake

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Science china(Technological Sciences) 2008年第S2期51卷 110-122页

作者： GONG JianYa,SUI HaiGang,SUN KaiMin,MA GuoRui & LIU JunYi state key {2. of Information engineering in Surveying,Mapping and Remote Sensing,wuhan University,wuhan 430072.china state key {2. of Information engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan China

Aiming at object fragmentation and poor detection results caused by discontinuous segmentation scale in object-level change detection,a new object-level change detection method based on the full-scale object tree is presented in this *** core idea of this new algorithm is to establish the full-scale object tree based on convexity model theory and integrate full-scale image segmentation techniques and change detection into the whole *** Wenchuan Earthquake images are taken as an example to discuss the new method for earthquake damage detection and evaluation in urban area,landslide detection,and extraction of barrier lake *** application shows that the new method is robust and it provides an advanced tool for the quantitative detection and evaluation of earthquake damage.

关键词： change detection convexity model image segmentation full-scale object tree Wenchuan Earthquake

Damping Properties of Flexible Epoxy Resin

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Journal of wuhan University of Technology(Materials Science) 2008年第3期23卷 411-414页

作者：王翔刘韩星 School of Materials Science and engineering Wuhan University of Technology state key {2. of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

Amino-terminated polyethers and amino-terminated polyurethane were used as curing agent to cure the epoxy resin together and get a series of cured products. The damping properties of the composites were studied by DMA test at different measurement frequencies. Damping mechanical tests show that the flexible epoxy resin has higher loss factor than common epoxy. The highest loss factor reaches 1.57. Also the height and position of loss factor peak of the flexible epoxy resin varies by changing the content of amino-terminated polyethers. Results shows that the flexible epoxy resin can be used as damping polymer materials at room temperature or in common frequency range.

关键词： flexible epoxy damping properties amino-terminated polyethers amino-terminated polyurethane

Exsolution of ilmenite and Cr-Ti magnetite from olivine of garnet-wehrlite

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Science china Earth Sciences 2005年第9期48卷 1368-1376页

作者： LIU Xiangwen1,2. JIN Zhenmin1,3, QU Jing2.& WANG Lu2.1. state key {2. of Geological Processes and Mineral Resources, china University of Geosciences, wuhan 430074, china 2. Graduate School of china University of Geosciences, wuhan 430074, china 3. Faculty of Earth Sciences, china University of Geosciences, wuhan 430074, china state key {2. of Geological Processes and Mineral Resources China University of Geosciences Wuhan China Graduate School of china University of Geosciences Wuhan China Faculty of Earth Sciences China University of Geosciences Wuhan China

Exsolution of rod-like ilmenite (Ilm) and Cr-Ti magnetite (Mt) have been found in olivine of garnet-wehrlite from the core of Chinese Continental Sciences Drilling (CCSD). Their composition, morphology, crystal structure and their topotaxies with host olivine have been studied in detail by the transmission electron microscopy (TEM) and electron probe microanaly- sis (EPMA) technique. It shows that rod-like Ilm exsolution reported in this paper has similar characteristic with that of Alpe Arami olivine, while Cr-Ti magnetite exsolution mentioned in this paper has large discrepancy with chromite exsolution in Alpe Arami olivine. These observations suggest that both of the exsolutions found in this paper should be solid solution phases in β-olivine at their first period, then experiencing decomposition of solid solution and therefore forming Ilm and Cr-Ti magnetite exsolution with the pressure decreasing. So, this garnet-wehrlite perhaps had been ever located in mantle transition zone with a minimum depth of 300 km.

关键词： garnet-wehrlite, ilmenite, magnetite, exsolution, CCSD.

Optimization Research of Urban Space Configuration Based on Space Syntax

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 47-52页

作者： Zhu Qing & Wang Jingwen state key {2. of Information engineering in Surveying Mapping and Remote Sensing, wuhan University, wuhan 430072, china state key {2. of Information engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430072 China

In this paper, a new method based on the space syntax is presented to optimize the urban space configuration. Space syntax theory is used to detect systematically whether one urban space configuration is optimal or not from four aspects including traffic space, cognition space, land use space and culture space. After introducing the computational and cognitive aspects of space syntax for the research of urban space, a framework of urban space optimization based on space syntax is proposed, then the integration with GIS and the extension to third dimension are discussed. Finally, a case study for Kanmen town of Zhejiang province of *** is illustrated by using Axwoman tool.

关键词： space syntax urban space optimizatoine GIS

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 engineering, Nanjing University of Posts and Telecommunications, Nanjing 2.0003, Jiangsu, china 2. Department of Computer Science and engineering, Southeast University, Nanjing 2.0096, Jiangsu, china 3. Jiangsu Institute of software Quality, Nanjing 2.0096 Jiangsu, china 4. The state key laboratory of software engineering, wuhan University, wuhan 430072, Hubei, china Department of Computer Science and engineering Nanjing University of Posts and Telecommunications Nanjing Jiangsu China Department of Computer Science and engineering Southeast University Najing Jiangsu China Jiangsu Institute of software Quality Nanjing Jiangsu China The state key {2. of software engineering Wuhan University Wuhan Hubei 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 311. 135.4 Foundation item: Supported by the National Natural Science Fundation of china (60373066). National Grand Fundamental Research 973 Program of china (2.02.B312.0). Opening Foundation of state key laboratory of software engineering 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

Characterization of Pozzolanic Reaction and Its Effect on the C-S-H Gel in Fly Ash-cement Paste

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Journal of wuhan University of Technology(Materials Science) 2011年第2期26卷 320-325页

作者：王磊何真 state key {2. of Water Resources and Hydropower engineering Science Wuhan University

High resolution solid-state 2.Si MAS NMR,combined with XRD,SEM and FTIR were used to characterize the pozzolanic activity of FA,type of main pozzolanic reaction products,and the effect of pozzolanic reaction on the C-S-H microstructure in fly ash-cement （FC） *** experimental results indicate that in the hydrated FC paste with 30% dosage of FA at 3 d,FA partially participated in the pozzolanic reaction,while,at 12. d,FA largely *** the hydration of FC paste at laboratory temperature,the pozzolanic reaction products are C-S-H gel rather than zeolitic ***,after the covalent bonds of Si-O-Si,Si-O-Al and Al-O-Al in the structure of FA are broken,monosilicates Si-OH and Al-OH groups form,these chemical species can connect C-S-H dimers,thus producing more Al-free C-S-H and aluminous C-S-H than in the plain cement *** increased content of Al for Si substitution in the bridging tetrahedra of C-S-H may decrease the stability of C-S-H,which results in a rather obvious loss in the mechanical strength of hardened FC paste.

关键词： NMR C-S-H microstructure dimer polymerization