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science china(Technological sciences) 2010年第6期53卷 1520-1525页

作者： LAI JianZhong1 & SUN Wei2.1 Department of materials science and Engineering,{2. university of science and Technology,{2. 2.0094,china 2.college of materials science and Engineering,southeast university,nanjing 2.1189,china 1. Department of materials science and Engineering Nanjing University of Science and Technology Nanjing 210094 China2. College of Materials Science and Engineering Southeast University Nanjing 211189 China

Ultra-high performance cementitious composites (UHPCC) were prepared by replacing 60% of cement with ultra-fine industrial waste *** dynamic damage and compressive stress-strain relations of UHPCC were studied using split Hopkinson pressure bar (SHPB).The damage of UHPCC subjected to repeated impact was measured by the ultrasonic pulse velocity *** show that the dynamic damage of UHPCC increases linearly with impact times and the abilities of repeated impact resistance of UHPCC are improved with increasing fiber volume *** stress waves on impact were recorded and the average stress,strain and strain rate of UHPCC were calculated based on the wave propagation *** effects of strain rate,fibers volume fraction and impact times on the stress-strain relations of UHPCC were *** show that the peak stress and elastic modulus decrease while the strain rate and peak strain increase gradually with increasing impact times.

关键词： ultra-high performance cementitious composites (UHPCC) split Hopkinson pressure bar (SHPB) repeated impact damage stress-strain

Dynamic Mechanical Behaviour of Ultra-high Performance Fiber Reinforced Concretes

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Journal of Wuhan university of Technology(materials {2.) 2008年第6期23卷 938-945页

作者：赖建中 Department of materials science & Engineering Nanjing University of Science & Technology

Ultra-high performance fiber reinforced concretes （UHPFRC） were prepared by replacing 60% of cement with ultra-fine industrial waste powder. The dynamic mechanical behaviour of UHPFRC with different fiber volume fraction was researched on repeated compressive impact in four kinds of impact modes through split Hopkinson pressure bar （SHPB）. The experimental results show that the peak stress and elastic modulus decrease and the strain rate and peak strain increase gradually with the increasing of impact times. The initial material damage increases and the peak stress of the specimen decreases from the second impact with the increasing of the initial incident wave. Standard strength on repeated impact is defined to compare the ability of resistance against repeated impact among different materials. The rate of reduction of standard strength is decreased by fiber reinforcement under repeated impact. The material damage is reduced and the ability of repeated impact resistance of UHPFRC is improved with the increasing of fiber volume fraction.

关键词： ultra-high performance fiber reinforced concretes split Hopkinson pressurebar dynamic repeated impact

Internal relative humidity and creep of concrete with modified admixtures

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Progress in Natural science:materials International 2011年第5期21卷 426-432页

作者： Zhi-hai HE~(1,2.,Chun-xiang QIAN~(1,2. 1.college of materials {2. and Engineering,southeast university,nanjing 2.1189,china 2.Jiangsu Key Lab of Construction materials,nanjing 2.1189,china [a] college of materials {2. and Engineering Southeast University Nanjing 211189 China [b] Jiangsu Key Lab of Construction materials Nanjing 211189 China

The creep characteristics and internal relative humidity(IRH) of concrete with shrinkage reducing admixtures(SRA),poly vinyl alcohol fiber(PVAF) and a mixture of fly ash and slag(MFS) were investigated by the self-made loading *** pore structure was tested,and the relationship of creep and IRH of concrete was *** results indicate that MFS and SRA reduce the total creep and delay the change of ***,the effect of PVAF is contrary,relative to MFS and *** total creep depends largely on drying *** basic creep of concrete is similar,which is significantly influenced by volume fraction of pores whose diameter is between 3.5 nm and 50 nm to the total pore(VP),and IRH of concrete is connected with *** is easy to obtain a good linear relationship predicting the creep of concrete according to the change of IRH.

关键词： modified admixture internal relative humidity total creep drying creep basic creep porosity

Two-and Three-Dimensional Chloride Ingress into Fly Ash Concrete

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Journal of Wuhan university of Technology(materials {2.) 2011年第5期26卷 978-982页

作者：张云升 Jiangsu Key Laboratory for Construction materials Southeast University college of materials {2. and Engineering Southeast University

2.,3D chloride ion concentration at the edge and corner zones were systematically investigated for fly ash concretes made with different cement replacement percentage by fly ash （0%,10%,2.%,40%,60%）,water to binder ratios （0.3,0.35,0.4）,and curing ages （2. d,90 d）.An interaction effect caused by 2. and 3D diffusion could obviously be observed through the comparison with 1D testing *** order to quantify the interaction effect,2. and 3D diffusion interaction coefficients was proposed in this ***,the changes of 2. and 3D interaction coefficients with the change in the free chloride ion concentration were *** above research provide an insight into chloride ion attack on the edge and corner reinforcing bars of concrete structures in the field of civil engineering.

关键词： fly ash concrete chlorides two and three dimension ingress

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,{2.,china 2.college of materials science and Engineering,Hohai university,nanjing 2.0098,china 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

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 {2. and Engineering, Northwestern Polytechnical university, Xi’an 710072. china 2. college of materials {2. and Engineering, Henan university of {2. and Technology, Luoyang 471003, china 1. college of materials {2. and Engineering Northwestern Polytechnical University 710072 Xi’an China 2. college of materials {2. 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.

Integrated intelligent control analysis on semi-active structures by using magnetorheological dampers

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science china(Technological sciences) 2008年第12期51卷 2270-2284页

作者： XU ZhaoDong1 & GUO YingQing2.1Civil Engineering college, southeast university, {2. 2.0096, china 2.Automation college, southeast university, {2. 2.0096, china Civil Engineering college Southeast University Nanjing 210096 China Automation college Southeast University Nanjing 210096 China

The control strategy is very important for semiactive control or active control systems. An integrated intelligent control strategy for building structures incorpo rated with magnetorheological (MR) dampers subjected to earthquake excitation is proposed. In this strategy, the time-delay problem is solved by a neural network and the control currents of the MR dampers are determined quickly by a fuzzy controller. Through a numerical example of a three-storey structure with one MR damper installed in the first floor, the seismic responses of the uncontrolled, the intelligently controlled, the passiveon controlled, and the passive-off controlled structures under different earthquake excitations are analyzed. Based on the numerical results, it can be found that the time domain and the frequency domain responses are reduced effectively when the MR damper is added in the structure, and the integrated intelligent control strategy has a better earthquake mitigation effect.

关键词： magnetorheological damper semi-active control intelligent

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,{2. 2.0096,P.R.china 2.Institute of sciences,university of science and Technology of the PLA,{2. 2.0007,P.R.china 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.

MMSE relay precoding schemes based on quantization error compensation for multi-relay system

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science china(Information sciences) 2010年第12期53卷 2548-2556页

作者： LI Ting 1,2.& YANG LuXi 2.1 college of Communication and Information Engineering,nanjing {2. of Posts and Telecommunications,nanjing 2.0003,china 2.School of Information science and Engineering,southeast university,nanjing 2.0096,china 1. college of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China2. School of Information Science and Engineering Southeast University Nanjing 210096 China

In order to deal with the performance degradation resulting from the quantization error,this paper introduces the statistics of Grassmannian codebook's quantization error into relay precoding design for multirelay *** on the two-step MMSE optimization algorithm for relay precoding and receiver equalizing with full feedback under QoS requirements,we first propose a limited feedback two-step MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation,and then we propose a limited feedback joint MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation subject to a global power constraint at the output of *** results show that the proposed joint MMSE optimization scheme with quantization error compensation has a much lower bit-error rate than the two-step MMSE optimization scheme with quantization error compensation and the joint MMSE optimization scheme without quantization error compensation.

关键词： multi-relay precoding limited feedback minimum mean square error

Web Application Comprehension Based on Dependence Analysis

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Wuhan university Journal of Natural sciences 2004年第5期9卷 731-734页

作者： WU Jun-hua 1,2., XU Bao-wen 1 , JIANG Ji-xiang 1 1.Department of Computer science and Engineering, southeast university, {2. 2.0096, Jiangsu, china 2.college of Computer science and Engineering, {2. university of Technology, {2. 2.0009, Jiangsu , china southeast university Department of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***) Najing university of Technology College of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.41156.37) (ISNI:***) southeast university Department of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***)

Many research indicate a lot of money and time are spent on maintaining and modifying program delivered. So the policies to support program comprehension are very important. Program comprehension is a crucial and difficult task. Insufficient design, illogical code structure, short documents will enhance the comprehensive difficulty. Developing Web application is usually a process with quick implementation and delivery. In addition, generally a Web application is coded by combining mark language statements with some embedded applets. Such programming mode affects comprehension of Web applications disadvantageously. This paper proposes a method to improving understanding Web by dependence analysis and slice technology. Key words Web application comprehension - program dependence - hyper graph - pogram slicing CLC number TP 311 Foundation item: Supported in part by the Young Scientist’s Fund of NSFC (60373066, 6030302.). National Grand Fundamental Research 973 Program of china (2.02.B312.00) and National Research Foundation for the Doctoral Program of Higher Education of chinaBiography: WU Jun-hua (1965-), female, Ph. D. research direction: software engineering.

关键词： Web application comprehension program dependence hyper graph pogram slicing