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Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

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Progress in Natural science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2.and Luo Zhexian2.1. Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 10002., china 2. {2. University of information sciences & Technology, {2. 2.0044, china) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China nanjing University of information {2.s & Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 12.0 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation

Effect of Pozzolanic Reaction Products on Alkali-silica Reaction

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Journal of Wuhan University of Technology(Materials science) 2006年第3期21卷 168-171页

作者：魏风艳 Shanghai K. Wah Concrete Co.Ltd Shanghai 200030China

The effect of fly ash on controlling alkail-silica rection （ASR） in simudated alkali solution was studied. The expausion of mortar bars and the content of Ca（ OH）2.in cement paste cured at 80 °G for 91 d were measured. Traasmission electron microscopy （TEM） and high-resolution transmission electron microscot9 （HRTEM） were employed to study the microstructure of C-S-H. TEM/ energy dispersive spectroscopy （EDS） leas then used to determine the composition of C-S-H. The pore structure of the paste was analyzed by mercury intntsion porosimetry （MIP）. The results show that the contents of fly ash of 30% and 45% can well inhibit ASR. And the content of Ca（OH） 2.decreases with the increase of fly ash. That fly ash reacted with Ca（OH）2.to produce C-S-H with a low Ca/Si molar ratio could bind more Na^＋ and K^＋ ious, and produce a reduction in the amount of soluble alkali available for ASR. At the same time, the C- S- H produced by pozzolanic reaction converted large pores to snudler ones （ gel pores smaller than 10 nm ） to deusify the pore structure. Perhaps that could inhibit alkali trausport to aggregate for ASR.

关键词： alkali Ca/ Si molar ratio C-S-H alkali-silica reaction

Comparison of the fracture process of the rubberized concrete and plain concrete under bending load

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science china(Technological sciences) 2010年第6期53卷 1526-1533页

作者： ZHANG YaMei1,WANG Chao2.LU Yi1 & MA AiBin2.1 Jiangsu Key Laboratory of Construction Materials,southeast University,nanjing 2.1189,{2. 2.College of Materials science and engineering,Hohai University,nanjing 2.0098,{2. 1. Jiangsu Key Laboratory of Construction Materials Southeast University Nanjing 211189 China2. College of Materials Science and Engineering Hohai University Nanjing 210098 China

Acoustic emission (AE) technique is employed to investigate the damage process of the notched plain concrete and rubberized concrete specimens under 3-point bending *** signals in the fracture process of notched specimens are illustrated by analyzing the distribution of amplitude and hit rate of AE *** signals in the rubberized concrete have lower activity and amplitude than in the plain *** AE location analysis,it is found that the high energy events mainly are distributed near the notch *** to AE energy,the fracture process zone (FPZ) is *** comparing the FPZ of both concretes,it is found that the incorporation of rubber particles in concrete can greatly alleviate the damage process of concrete specimens and the damage zone in the rubberized concrete is much smaller than in the plain *** moment tensor is also used to analyze the type of cracks and it is found that tensile cracks dominate the early period of loading,while shear cracks become dominant with propagation of cracks in late load period.

关键词： concrete rubberized concrete acoustic emission damage moment tensor

Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 506-515页

作者： WANG Shi-dong1, 2. LIU Chang-hua2. ZHANG He-bing2.1. College of Resources science and Technology, Beijing Normal University, Beijing 100875, china 2. {2. of Surveying and Land information engineering, Henan Polytechnic University, Jiaozuo 454000, china [a] College of Resources science and Technology Beijing Normal University Beijing 100875 China [b] school of Surveying and Land information {2. Henan Polytechnic University Jiaozuo 454000 China

Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

关键词： mining area land reclamation suitability evaluation Gaoqiao bauxite mine

Interactive group decision making procedure based on uncertain multiplicative linguistic preference relations

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Journal of Systems engineering and Electronics 2010年第3期21卷 408-415页

作者： Zeshui Xu1,2.1.College of Economics and Management,southeast University,nanjing 2.0096,P.R.{2. 2.Institute of sciences,University of science and Technology of the PLA,nanjing 2.0007,P.R.{2. College of Economics and Management Southeast UniversityNanjing 210096P.R.China Institute of sciences University of Science and Technology of the PLANanjing 210007P.R.China

Group decision making problems are investigated with uncertain multiplicative linguistic preference *** unbalanced multiplicative linguistic label set is introduced,which can be used by the experts to express their linguistic preference information over *** uncertain linguistic weighted geometric mean operator is utilized to aggregate all the individual uncertain multiplicative linguistic preference relations into a collective one,and then a simple approach is developed to determine the experts＇ weights by utilizing the consensus degrees among the individual uncertain multiplicative linguistic preference relations and the collective uncertain multiplicative linguistic preference ***,a practical interactive procedure for group decision making is proposed based on uncertain multiplicative linguistic preference relations,in which a possibility degree formula and a complementary matrix are used to rank the given ***,the proposed procedure is applied to solve the group decision making problem of a manufacturing company searching the best global supplier for one of its most critical parts used in assembling process.

关键词： group decision making uncertain multiplicative linguistic preference relations unbalanced multiplicative linguistic label set consensus degree interaction.

Numerical study on optical and electric-thermal performance for solar concentrating PV/T air system

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science china(Technological sciences) 2009年第12期52卷 3514-3520页

作者： SUN Jian 1,2.&SHI MingHeng 1 1school of Energy and Environment,southeast University,{2.,china 2.epartment of Thermal Energy engineering,Jingdezhen Ceramic Institute,Jingdezhen 333001,china 1. school of Energy and Environment Southeast University Nanjing 210096 China 2. Department of Thermal Energy engineering Jingdezhen Ceramic Institute Jingdezhen 333001 China

Hybrid photovoltaic/thermal(PV/T)system with solar concentrator is an effective way to improve solar energy conversion *** this work,a single-pass PV/T air system with a three-trough compound parabolic concentrator(CPC)of concentration ratio 2.0 is designed and the solar incident distributions at the solar cell surface are calculated by ray tracing *** on energy balance,the heat transfer models of all main components in this system are *** effects of some main designing and operational parameters on the electric-thermal performance of the system are analyzed. The results show that the solar radiation intensity can be higher than 12.0 W/m 2.at most area of the cell *** temperature of the air and cell surface increases along the length of the *** the system efficiency of the CPC is higher than that of the system without the *** thermal efficiency, exergy and electrical efficiency of this CPC system increase with increasing of the air mass flow rate and the length of the *** increasing packing fraction the electrical efficiency increases,but the thermal efficiency *** exergy efficiency increases slightly with the packing fraction *** data obtained in this work are valuable for the design and operation for this kind of solar concentrating PV/T systems.

关键词： photovoltaic/thermal system CPC exergy efficiency thermal and electricity performance optical

Constructing Three-Dimension Space Graph for Outlier Detection Algorithms in Data Mining

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Wuhan University Journal of Natural sciences 2004年第5期9卷 585-589页

作者： ZHANG Jing 1,2., SUN Zhi-hui 1 1.Department of Computer science and engineering, {2. University, nanjing 2.0096, Jiangsu, china 2.Department of Electricity and information engineering, Jiangsu University, Zhenjiang 2.2.01, Jiangsu, china Department of Computer science and engineering Southeast University. Nanjing 210096 Jiangsu China

Outlier detection has very important applied value in data mining literature. Different outlier detection algorithms based on distinct theories have different definitions and mining processes. The three-dimensional space graph for constructing applied algorithms and an improved GridOf algorithm were proposed in terms of analyzing the existing outlier detection algorithms from criterion and theory. Key words outlier - detection - three-dimensional space graph - data mining CLC number TP 311. 13 - TP 391 Foundation item: Supported by the National Natural science Foundation of china (70371015)Biography: ZHANG Jing (1975-), female, Ph. D, lecturer, research direction: data mining and knowledge discovery.

关键词： outlier detection three-dimensional space graph data mining

Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science china(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2. LIU Ping2. DONG Qiming2.& LI Hejun1 1. College of Materials science and engineering, Northwestern Polytechnical University, Xi’an 710072. {2. 2. College of Materials science and engineering, Henan University of science and Technology, Luoyang 471003, {2. 1. College of Materials science and engineering Northwestern Polytechnical University 710072 Xi’an China 2. College of Materials science and engineering Henan University of Science and Technology 471003 Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

Early Age Compressive Strength of Pastes by Electrical Resistivity Method and Maturity Method

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Journal of Wuhan University of Technology(Materials science) 2011年第5期26卷 983-989页

作者：肖莲珍 school of Materials science and {2. Wuhan Institute of Technology

The compressive strength development of Portland cement pastes was investigated by the electrical resistivity method and the maturity *** experiments were carried out on the cement pastes with different water-cement ratios at different curing *** results show that the application of the maturity method has limitation to obtain the *** is found that both of the compressive strength and the electrical resistivity follow hyperbolic trend for all the *** hyperbolic equation of each mix is obtained to estimate the ultimate resistivity value which can probably be *** relationship between electrical resistivity and compressive strength of the cement pastes is established based on the test results and interpreted by the empirical Archie equation and a strength-porosity *** relationship between the electrical resistivity after temperature correction and the compressive strength was linear and independent of curing temperature and water-cement ratio.

关键词： electrical resistivity cement hydration compressive strength maturity method