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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 university of Science and technology, nanjing 210094, china 2.college of civil engineering, nanjing university of technology, nanjing 210009, china 1. School of Science Nanjing University of Science and Technology Nanjing 210094 China 2. college of civil engineering Nanjing University of Technology Nanjing 210009 China

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

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, nanjing 210096, Jiangsu, china 2.college of Computer Science and engineering, nanjing university of technology, nanjing 210009, 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, 60303024). National Grand Fundamental Research 973 Program of china (2002CB312000) 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

Molecular group dynamics study on slip flow of thin fluid film based on the Hamaker hypotheses

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Science china(Technological Sciences) 2010年第7期53卷 1833-1838页

作者： ZHOU JianFeng, SHAO ChunLei & GU BoQin college of Mechanical and Power engineering, nanjing university of technology, nanjing 210009, china 1. college of Mechanical and Power engineering Nanjing University of Technology Nanjing 210009 China

The thin fluid film was assumed to consist of a number of spherical fluid molecular groups and the attractive forces of molecular group pairs were calculated by the derived equation according to the three Hamaker homogeneous material hypotheses. Regarding each molecular group as a dynamics individual, the simulation method for the shearing motion of multilayer fluid molecular groups, which was initiated by two moving walls, was proposed based on the Verlet velocity iterative algorithm. The simulations reveal that the velocities of fluid molecular groups change about their respective mean velocities within a narrow range in steady state. It is also found that the velocity slips occur at the wall boundary and in a certain number of fluid film layers close to the wall. Because the dimension of molecular group and the number of group layers are not restricted, the hypothetical thickness of fluid film model can be enlarged from nanometer to micron by using the proposed simulation method.

关键词： Hamaker hypotheses molecular group velocity slip Lennard-Jones potential

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, nanjing 210096, china 2 Automation college, Southeast university, nanjing 210096, 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

Statistical study of cement additives with and without chloride on performance modification of Portland cement

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Progress in Natural Science:Materials International 2011年第3期21卷 246-253页

作者： Hong HUANG,Xiao-dong SHEN State Key Laboratory of Materials-Oriented Chemical engineering,college of Material Science and engineering, nanjing university of technology,nanjing 210009,china State Key Laboratory of Materials-Oriented Chemical engineering College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The effectiveness of cement additives with and without chloride on the fluidity and the strength development of Portland cement was compared by using statistical full factorial *** experimental results show that the cement additive containing CaCl2and Ca(NO3)2can enhance early strength of cement ***,Ca(NO3)2is less effective than CaCl2even if it is combined with other organic chemicals such as alkanolamine and *** significant difference is found between CaCl2and Ca(NO3)2influencing the fluidity and 28 d strength of *** fluidity is determined by saccharide and its interaction with *** 28 d strength enhancement is determined by *** fluidity as well as the mechanical performance of treated cement can be significantly improved by combining Ca(NO3)2with TIPA and saccharide.

关键词： Portland cement cement additive accelerator type fluidity strength development full factorial design

Analysis of variance for testing method of cement in determination of strength

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Progress in Natural Science:Materials International 2011年第4期21卷 341-346页

The statistical tools such as descriptive statistics,full factorial design and analysis of source of variation were used to identify the potential factors that impact the validity of testing method for determining the strength of *** results showed that personal error impacted both accuracy and precision of test *** time associated with temperature fluctuation resulted in strength variation but did not impact the precision of test in all curing *** compactions did not impact the precision of test but resulted in the strength variation on 3 d and 28 d *** methods for the initial moist air curing significantly impacted the precision of testing method and resulted in the strength variation of cement on 1 d.

关键词： testing method of cement analysis of variance strength accuracy precision

Modal identification of system driven by lévy random excitation based on continuous time AR model

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Science china(Technological Sciences) 2009年第12期52卷 3649-3653页

作者： DU XiuLi 1,2 &WANG FengQuan 1 1 college of civil engineering,Southeast university,nanjing 210096,china 2 School of Mathematical Sciences,nanjing Normal university,nanjing 210097,china college of civil engineering Southeast University Nanjing 210096 China School of Mathematical Sciences Nanjing Normal University Nanjing 210097 China

Based on the continuous time AR model,this paper presents a new time-domain modal identification method of LTI system driven by the uniformly modulated lévy random *** structural dynamic equation is first transformed into the observation equation and the state equation(namely,stochastic differential equation).Based on the property of the strong solution of the stochastic differential equation,the uniformly modulated function is identified *** by virtue of the Girsanov theorem,we present the exact maximum likelihood estimators of ***,the modal parameters are identified by eigen *** results show that the method not only has high precision and robustness but also has very high computing efficiency.

关键词： modal identification uniformly modulated function CAR model lévy process exact maximum likelihood estimator

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 university of Information Science & technology, nanjing 210044, china 2.college of Automation engineering, nanjing university of Aeronautics and Astronautics, nanjing 210016, china 1. college of Information & Control Nanjing University of Information Science & Technology Nanjing 210044 China 2. college of Automation engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 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

Mesoporous Si-MCM-48 membrane prepared by pore-filling method

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Science china(Technological Sciences) 2010年第4期53卷 1064-1068页

作者： XU DeKan & FAN YiQun State Key Laboratory of Materials-Oriented Chemical engineering,college of Chemistry and Chemical engineering,nanjing university of technology,nanjing 210009,china 1. State Key Laboratory of Materials-Oriented Chemical engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 China

Mesoporous MCM-48 membranes were prepared on asymmetric zirconia tubular support with an average pore size of 0.2 μm by hydrothermal *** support should be pretreated with H2O as a pore-filling substance to prevent the sol solution from infiltrating into the support *** SEM showed that the MCM-48 membrane was composed of tightly-connected spherical *** single gas N2 and H2 permeation experiments confirm that crack-free membrane could be prepared by pore-filling method.N2 permeance of MCM-48 membrane,synthesized by secondary growth,can reach 5.66×10-7 mol/Pa·s·m2,and the H2/N2 separation factor was 3.47 under trans-membrane pressure of 0.05 MPa.

关键词： MCM-48 mesoporous membrane pore-filling

On the general expressions of finite Hankel transform

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2125-2130页

作者： JIANG Quan 1,2 & GAO CunFa 1 1 college of Aerospace engineering,nanjing university of Aeronautics and Astronautics,nanjing 210016,china 2 School of civil engineering,Nantong university,Nantong 226019,china 1. college of Aerospace engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. School of Civil Engineering Nantong University Nantong 226019 China

The general expressions of finite Hankel transform are naturally deduced with the help of the property of Bessel *** equations in this paper can degenerate into three kinds of boundaries since all the coefficients in the boundary conditions are taken into *** results can be adopted in solving physics problems involving the finite Hankel transform.

关键词： hankel transform bessel function finite integral