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Explicit and Exact Solutions for theGeneralized reaction Duffing Equation

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Communications in Nonlinear Science and Numerical Simulation 1999年第3期4卷 3-5页

作者： Zhenya YAN and Hongqing ZHANG(Institute of mathematical Science, dalian university of technology, dalian 116024, china)E-mail: Zhanghq@*** Institute of mathematical Science Dalian University of Technology Dalian 116024 China

IntroductionInthesolitontheory,findingmoreefficientmethodplaysanimportantroleinsolvingexactsolutionsofnonlinearevolutionequationsll--4].Thefollowingreactionduffingequationwherea,6,dareallconstants,canbereducedtomanyfa... 详细信息

关键词： nonlinear evolution equation reaction duffing equation exact solution solitary wave solution period solution

The Nother and riemann-roch type theorems for piecewise algebraic curve

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Science china Mathematics 2007年第2期50卷 165-182页

作者： Yi-sheng LAI & ren-hong WANG College of Statistics and Mathematics, Zhejiang Gongshang university, Hangzhou 310018, china Institute of mathematical sciences, dalian university of technology, dalian 116024, china College of Statistics and Mathematics Zhejiang Gongshang University Hangzhou China Institute of mathematical sciences Dalian University of Technology Dalian China

A piecewise algebraic curve is a curve determined by the zero set of a bivariate spline function. In this paper, the Nother type theorems for Cμpiecewise algebraic curves are obtained. The theory of the linear series of sets of places on the piecewise algebraic curve is also established. In this theory, singular cycles are put into the linear series, and a complete series of the piecewise algebraic curves consists of all effective ordinary cycles in an equivalence class and all effective singular cycles which are equivalent specifically to any effective ordinary cycle in the equivalence class. This theory is a generalization of that of linear series of the algebraic curve. With this theory and the fundamental theory of multivariate splines on smoothing cofactors and global conformality conditions, and the results on the general expression of multivariate splines, we get a formula on the index, the order and the dimension of a complete series of the irreducible Cμpiecewise algebraic curves and the degree, the genus and the smoothness of the curves, hence the riemann-roch type theorem of the Cμpiecewise algebraic curve is established.

关键词： piecewise algebraic curve place cycle complete linear series.

Analytical theory of flexural behavior of concrete beam reinforced with textile-combined steel

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Science china(Technological sciences) 2010年第6期53卷 1700-1710页

作者： XU ShiLang & YIN Shiping Department of Civil Engineering,dalian university of technology,dalian 116024,china Department of Civil Engineering Dalian University of Technology Dalian China

Textile-reinforced concrete (TrC) is a new high performance cementitious composite material,which not only has superior corrosion resistance but also can effectively limit the development of concrete cracks and make the crack width and spacing of concrete become ***,due to the brittle feature of fiber materials,the TrC structural member has no distinct failure symptom when it arrives at its ultimate *** the same time,ordinary reinforced concrete (rC) elements have large dead weight and can not efficiently restrict the expansion of the main crack of structures because of the restriction of their special cover *** order to overcome the disadvantages of both the TrC and the rC,a new architecture reinforced with textile-combined steel is proposed in this study,making full use of the advantages of the above two *** cover concrete at the tension zone of an rC element is partially replaced with TrC and thus the steel reinforcements replaced with textiles are *** with the old one,the new structure has less dead weight and has the merits of service safety and good *** flexural development process of the proper beam with this new structure is investigated in this paper and based on the plane section assumption,analytical equations are derived by using nonlinear analysis theory,including the load-carrying capacity at different stages and moment-curvature relationship and mid-span deflection during the entire loading *** between the calculated and the experimental results reveals satisfactory agreement and thus verifies the feasibility of the equations.

关键词： textile-reinforced concrete limiting the crack beam reinforced with textile-combined steel flexural behavior analytical theory

A HIGH rESOLUTION FINITE VOLUME METHOD FOr SOLVING SHALLOW WATEr EQUATIONS

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Journal of Hydrodynamics 2000年第1期12卷 35-41页

作者： Wang Jia song school of Civil Engineering and Mechanics, Shanghai Jiaotong university, Shanghai 200030, p.r.chinaNi Hang gen Department of Civil and Structure Engineering, dalian university of technology, dalian 116024, p.r.china Shanghai Jiaotong Univ Shanghai China

A high resolution finite volume numerical method for solving the shallow water equations is developed in this paper. In order to extend finite difference TVD scheme to finite volume method, a new geometry and topology of control bodies is defined by considering the corresponding relationships between nodes and elements. This solver is implemented on arbitrary quadrilateral meshes and their satellite elements, and based on a second order hybrid type of TVD scheme in space discretization and a two step runge Kutta method in time discretization. Then it is used to deal with two typical dam break problems and very satisfactory results are obtained comparied with other numerical solutions. It can be considered as an efficient implement for the computation of shallow water problems, especially concerning those having discontinuities, subcritical and supercritical flows and complex geometries.

关键词： shallow water equations finite volume TVD scheme dam break bores

Enhanced Surface properties Induced by High Current pulsed Electron Beam (HCpEB) Treatment

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稀有金属材料与工程 2011年第S4期40卷 178-180页

作者： Hao Shengzhi1,2,Wang Huihui1,2,Li Mincai1,3,Xu Yang1,3,Dong Chuang1,3 1Key Laboratory of Materials Modification by Laser,Ion and Electron Beams,Ministry of Education,dalian university of technology,dalian 116024,china2school of physics and Optoelectronics Engineering,dalian university of technology,dalian 116024,china3school of Material Science and Engineering,dalian university of technology,dalian 116024,china dalian Univ Technol Minist Educ Key Lab Mat Modificat Laser Ion & Electron Beams Dalian 116024 Peoples R China dalian Univ Technol Sch Phys & Optoelect Engn Dalian 116024 Peoples R China dalian Univ Technol Sch Mat Sci & Engn Dalian 116024 Peoples R China

High current pulsed electron beam (HCpEB) has been developed as a useful tool for surface treatment of *** the present work,the fundamental principle of HCpEB source was described along with the device configuration and working *** the different kinds of HCpEB surface treatment experiments conducted,the enhanced surface properties induced by HpCEB treatment were illustrated and explained with their microstructure characterization results.

关键词： high current pulsed electron beam surface treatment microstructure property

Timeliness evaluation of task-oriented networked space-based information system

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Journal of Systems Engineering and Electronics 2011年第4期22卷 621-627页

作者： Chen Chen 1,2,and Jie Chen 2,3 1.Department of Automation,Tsinghua university,Beijing 100084,p.r.china 2.school of Automation,Beijing Institute of technology,Beijing 100081,p.r.china 3.Complex System Intelligent Control and Decision,Ministry of Education,Beijing 100081,p.r.china Department of Automation Tsinghua University Beijing 100084 P. R. China school of Automation Beijing Institute of Technology Beijing 100081 P. R. China school of Automation Beijing Institute of Technology Beijing 100081 P. R. China Complex System Intelligent Control and Decision Ministry of Education Beijing 100081 P. R. China

Task-oriented networked information system is an integrated information system which builds on multi-satellite networking to accomplish one or more tasks. In the background of emer- gency relief for applications, system working flow and response process are analyzed, and a timeliness effectiveness evaluation index system is constructed at multi-task level. The effectiveness is a measurement of promptness of information return. In evalua- tion process, system performance and tasks are associated, then an evaluation model based on efficacy function is established, and different evaluation criteria are selected for different tasks. A distributed simulation system is constructed, and the execution of task is decomposed. The simulation platform provides a comprehensive data source for evaluation. The results are easy to compare with each other, which reflects system time efficiency in different satellites networks and provides actual systems with basis and reference for design and application.

关键词： timeliness efficacy function space-based informationsystem simulation system.

INFINITE ELEMENT METHOD FOr THE EXTErIOr prOBLEMS OF THE HELMHOLTZ EQUATIONS

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Journal of Computational Mathematics 2000年第6期18卷 657-672页

作者： Lung-an Ying (school of mathematical sciences, peking university, Beijing 100871, china) 北京大学北京 100871

There are two cases of the exterior problems of the Helmholtz equation. If λ ≥ 0 the bilinear form is coercive, and if λ < 0 it is the scattering problem. We give a new approach of the infinite element method, whic... 详细信息

There are two cases of the exterior problems of the Helmholtz equation. If λ ≥ 0 the bilinear form is coercive, and if λ ring problem. We give a new approach of the infinite element method, which enables us to solve these exterior problems as well as corner problems. A numerical example of the scattering problem is given. [ABSTrACT FrOM AUTHOr]

关键词： Helmholtz equation exterior problem infinite element method

Fractal Dimension Analysis of the Fine Aggregate Gradation of Interlocking Skeleton Asphalt Mixture

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Journal of Wuhan university of technology(Materials Science) 2011年第3期26卷 567-572页

作者：刘慧 school of Civil & Hydraulic Engineering Dalian University of Technology

By analyzing the fine aggregate gradation scales from standards,fine aggregate in the asphalt mixture is regarded as a whole research object and fractal dimensions X of the samples were obtained by linear regression and（AC-13）is 2.43-2.56,Sup-13 is 2.28-2.54,SMA-13 is 2.66-2.88 and SAC-13 is *** the dense gradation mixture,there are little different between fractal dimensions of coarse and fine aggregates but it makes sense for skeleton asphalt *** a given coarse aggregate gradation and the same percentage of coarse aggregates,the compressive strengths and splitting strengths of the asphalt mixture are studied when the fractal dimensions are selected as 2.60,2.65 and 2.70,*** asphalt-stone ratio is less than optimal asphalt-stone ratio,the higher compressive strength is,the bigger X can be *** asphalt-stone ratio is larger than optimal asphalt-stone ratio,little difference of compressive strength can be observed under these three *** largest splitting strength can be got when X is 2.65,and larger splitting strength can be observed with the ascending of the asphalt-stone ratio.

关键词： fractal dimension fine aggregate gradation compressive strength splitting strength

LEVEL SET METHOD FOr TOpOLOGICAL OpTIMIZATION AppLYING TO STrUCTUrE, MECHANISM AND MATErIAL DESIGNS

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 200-209页

作者： Mei Yulin Wang Xiaoming Department of Mechanical Engineering,dalian university of technology,dalian 116024,china Department of Mechanical Engineering Dalian University of Technology Dalian 116024

Based on a level set model, a topology optimization method has been suggestedrecently. It uses a level set to express the moving structural boundary, which can flexibly handlecomplex topological changes. By combining vector level set models with gradient projectiontechnology, the level set method for topological optimization is extended to a topologicaloptimization problem with multi-constraints, multi-materials and multi-load cases. Meanwhile, anappropriate nonlinear speed, mapping is established in the tangential space of the activeconstraints for a fast convergence. Then the method is applied to structure designs, mechanism andmaterial designs by a number of benchmark examples. Finally, in order to further improvecomputational efficiency and overcome the difficulty that the level set method cannot generate newmaterial interfaces during the optimization process, the topological derivative analysis isincorporated into the level set method for topological optimization, and a topological derivativeand level set algorithm for topological optimization is proposed.

关键词： Level set method Topology optimization Mean curvature flow Materialdesign Mechanism design Topological derivative