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Three-dimensional elasticity solution of simple-supported rectangular plate on point supports, line supports and elastic foundation

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science china(Technological sciences) 2009年第3期52卷 584-589页

作者： XU YePeng1 & ZHOU Ding2.1 School of science, nanjing {2. of science and technology, nanjing 2.0094, china 2.college of Civil Engineering, nanjing university of technology, nanjing 2.0009, china School of science Nanjing University of Science and Technology college of Civil Engineering Nanjing University of Technology

This paper studies the bending of simple-supported rectangular plate on point supports, line supports and elastic foundation. On the basis of three-dimensional elasticity theory, the exact expressions of the displacement functions, which satisfy the governing differential equations and the simply supported boundary conditions at four edges of the plate, are analytically derived. The reaction forces of the in- termediate supports are regarded as the unknown external forces acting on the lower surface of the plate. The unknown coefficients are then determined by the boundary conditions on the upper and lower surfaces of the plate. Comparing the numerical results obtained from the proposed method to those obtained from Kirchhoff plate theory, Mindlin plate theory and those obtained from the commer- cial finite element software ANSYS, the high accuracy of the present method has been demonstrated.

关键词： rectangular plate point support line support elastic foundation displacement stress three-dimensional elasticity solution

Dynamic damage and stress-strain relations of ultra-high performance cementitious composites subjected to repeated impact

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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,nanjing {2. of science and technology,nanjing 2.0094,china 2.college of Materials science and Engineering,Southeast {2.,nanjing 2.1189,china Department of Materials science and Engineering Nanjing University of Science and Technology college of Materials science and Engineering Southeast University

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

Resolution method for overlapping peaks based on the fractional-order differential

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science china Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2.& ZHENG Gang2.1 college of Information & Control, nanjing {2. of Information science & technology, nanjing 2.0044, china 2.college of Automation Engineering, nanjing {2. of Aeronautics and Astronautics, nanjing 2.0016, china college of Information & Control Nanjing University of Information Science & Technology Nanjing China college of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

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

A new heuristic algorithm for the circular packing problem with equilibrium constraints

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science china(Information sciences) 2011年第8期54卷 1572-1584页

作者： LIU JingFa 1,2.LI Gang 3 & GENG HuanTong 1 1 School of computer and Software,nanjing {2. of Information science & technology,nanjing 2.0044,china 2.Network Information Center,nanjing {2. of Information science & technology, nanjing 2.0044,china 3 School of Mathematics and Physics,nanjing {2. of Information science & technology,nanjing 2.0044,china School of computer and Software Nanjing University of Information Science & Technology Network Information Center Nanjing University of Information Science & Technology School of Mathematics and Physics Nanjing University of Information Science & Tec

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 11 representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 11 instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization

A Raw Signal Simulator for Bistatic SAR

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Chinese Journal of Aeronautics 2009年第4期22卷 434-443页

作者： Xia Weijie,Zhou Jianjiang college of Information science and {2.,nanjing university of Aeronautics and Astronautics,nanjing 2.0016,china college of Information science and {2. Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This article proposes a new efficient raw signal simulator for the bistatic synthetic aperture radar （SAR） based on 2. fast Fourier transform （FFT） to deal with cases of both ideal trajectory and trajectory deviation. It begins with analyzing the geometric configuration and the range history of the bistatic SAR in side-looking and squint modes of ideal trajectory as well as trajectory deviation. Then a detailed and mathematical study is conducted on the equivalence relation of bistatic-to-monostatic applications （BTMA） in the case of ideal trajectory and trajectory deviation. Also a set of formulas are derived for the equivalence relation between bistatic SAR and monostatic SAR on some reasonable assumptions. Therefore, the application of the simulation method based on the 2. FFT for the monostatic SAR can be extended to the case of bistatic SAR. Finally, the simulation results prove the validity of this method. By comparing the efficiency of the proposed method with that of the time domain method, it is shown that the former is a few orders of magnitude higher.

关键词： bistatic synthetic aperture radar raw signal simulation fast Fourier transform

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 University Nanjing 210096 P. R. China Institute of sciences University of Science and Technology of the PLA Nanjing 210007 P. 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.

Basin filling algorithm for the circular packing problem with equilibrium behavioral constraints

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science china(Information sciences) 2010年第5期53卷 885-895页

作者： LIU JingFa1& LI Gang2.1School of computer and Software, nanjing {2. of Information science & technology, nanjing 2.0044, china 2.chool of Mathematics and Physics, nanjing {2. of Information science & technology, nanjing 2.0044, china School of computer and Software Nanjing University of Information Science & Technology School of Mathematics and Physics Nanjing University of Information Science & Technology

With the background of the satellite module layout design, the circular packing problem with equilibrium behavioral constraints is a layout optimization problem and NP-hard problem in math. For lack of a powerful optimization method, this problem is hard to solve. The energy landscape paving (ELP) method is a class of stochastic global optimization algorithms based on the Monte Carlo sampling. Based on the quasiphysical strategy and the penalty function method, the problem is converted into an unconstrained optimization problem. Here by combining the improved ELP method, the gradient method based on local search and the heuristic configuration update mechanism, a new global search algorithm, basin filling algorithm, is put forward. The numerical results show that the proposed algorithm is effective to solving the circular packing problem with equilibrium behavioral constraints, and is easy to be popularized to other layout optimization problems.

关键词： equilibrium behavioral constraints packing problem layout optimization

Selection of unitary operations in quantum secret sharing without entanglement

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science china(Information sciences) 2011年第9期54卷 1837-1842页

作者： XU Juan 1,CHEN HanWu 1,LIU WenJie 1,2.& LIU ZhiHao 1 1 School of computer science and Engineering,Southeast {2.,nanjing 2.0096,china 2.School of computer and Software,nanjing {2. of Information science and technology,nanjing 2.0044,china School of computer science and Engineering Southeast University School of computer and Software Nanjing University of Information Science and Technology

We propose a substitute-Bell-state attack strategy for quantum secret sharing schemes without entanglement,as well as a definition of the minimum failure probability of such attack strategy.A quantitative analysis of security degrees corresponding to different unitary operations is also provided,when the secret sharing schemes without entanglement are stricken by substitute-Bell-state *** a result,the relation between the selection of unitary operations and the effect of substitute-Bell-state attack is shown,which can serve as an important guidance for the selection of unitary operations in designing and implementing quantum secret sharing schemes.

关键词： quantum secret sharing substitute-Bell-state attack unitary operation minimum failure probability