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MULTIPLICITY OF SOLUTIONS AND SOURCE TERMS IN A FOURTH ORDER NONLINEAR ELLIPTIC EQUATION

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Acta Mathematica Scientia 1999年第4期19卷 361-374页

作者： Choi Q-Heung Jung Tacksun(Departmctzt of Mathematics, Inha University, Incheon 402-751, KoreaDepartment of Mathematics, Kunsan National University, Kunsan 573-701, Korea) Inha Univ Dept Math Inchon 402751 South Korea Kunsan Natl Univ Dept Math Kunsan 573701 South Korea

The authors investigatc relations between multiplicity of solutions and sourceterms of the fourth order nonlinear elliptic boundary value problem under Dirichlet boundary condition △2u＋c△u = bu+＋f inΩ, wherc Ω is a bounded open set in Rn with smoothbonndary and the nonlinearity bu+ crosses eigenvalues of △2 ＋c△. They investigate therelatiolls when the source term is constant and when it is generated by two eigenfuntions.

关键词： Nonlinear elliptic equation solution source terms boundary value problem

L^p ESTIMATES FOR BI-INVARIANT OPERATORS ON CLASSICAL GROUPS

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Chinese Annals of Mathematics,Series B 1996年第4期17卷 435-444页

作者：范大山 ANHUI UNIV DEPT MATHHEFEI 230039PEOPLES R CHINA UNIV WISCONSIN DEPT MATH SCIMILWAUKEEWI 53201

The main purpose of this paper is to extend to classical groups a H*irmander multiplier theorem concerning translation invariant operators on L p spaces which are known for the n-torus.

关键词： H*irmander multiplier theorem L p space Classical group Poisson kernel

Thermal Oxidation Resistance of Rare Earth-Containing Composite Elastomer

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Journal of Rare Earths 2001年第3期19卷 192-197页

作者：邱关明张明周兰香中北里志井上真一冈本弘 Changchun Coll Opt & Fine Mech Dept Mat & Chem Engn Changchun 130022 Peoples R China Yangzhou Univ Dept Chem Engn Yangzhou 225002 Peoples R China Aichi Inst Technol Dept Appl Chem Toyota 4700392 Japan

The rare earth-containing composite elastomer was obtained by the reaction of vinyl pyridine-SBR (PSBR) latex with rare earth alkoxides, and its thermal oxidation resistance was studied. After aging test, it is found that its retention rate of mechanical properties is far higher than that of the control sample. The results of thermogravimetric analysis show that its thermal-decomposing temperature rises largely. The analysis of oxidation mechanisms indicates that the main reasons for thermal oxidation resistance are that rare earth elements are of the utility to discontinue autoxidation chain reaction and that the formed complex structure has steric hindrance effect on oxidation.

关键词： rare earths composite elastomer thermal oxidation resistance discontinue autoxidation steric structure

THE DEFECT ITERATION OF THE FINITE ELEMENT FOR ELLIPTIC BOUNDARY VALUE PROBLEMS AND PETROV-GALERKIN APPROXIMATION

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Journal of Computational Mathematics 1998年第2期16卷 152-164页

作者： Gao, JB Yang, YD Shih, TM Huazhong Univ Sci & Technol Dept Math Wuhan 430074 Peoples R China Guizhou Normal Univ Dept Math Guiyang 550001 Peoples R China Hong Kong Polytech Univ Dept Math Appl Hong Kong Peoples R China

In this paper we introduce a Petrov-Galerkin approximation model to the solution of linear and semi-linear elliptic boundary value problems in which piecewise quadratic polynomial space and piecewise linear polynomial space are used as the shape function space and the test function space, respectively. We prove that the approximation order of the standard quadratic finite element can be attained in this Petrov-Galerkin model. Based on the so-called 'contractivity' of the interpolation operator, we further prove that the defect iterative sequence of the linear finite element solution converge to the proposed Petrov-Galerkin approximate solution.

关键词： Petrov-Galerkin approximation defect iteration correction interpolation operator

Survivability analysis of wireless Ad hoc network using stochastic reward nets

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Journal of Harbin Institute of Technology(New Series) 2008年第4期15卷 535-539页

作者：赵靖崔刚刘宏伟王慧强 dept.of Computer Harbin Engineering University dept.of Computer Harbin Institute of Technology

To provide services in presence of failures or attacks in a timely manner, the network survivability was analyzed. Based on stochastic Petri nets, we put forward an effective model for ad hoe network and adopt a two-phase approach consisting of the steady-state availability analysis and the system transient performance analysis, then provide a quantitative approach for analysis of the network survivability. The results show that the proposed model is useful for the design and evaluation of the wireless ad hoc network.

关键词： survivability availability ad hoc network stochastic Petri nets

2D spiral pattern recognition based on neural network covering algorithm

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Journal of Harbin Institute of Technology(New Series) 2007年第3期14卷 330-333页

作者：黄国宏熊志化邵惠鹤 dept.of Information Guangdong University of Technology dept.of Automation Shanghai Jiaotong University

The main aim for a 2D spiral recognition algorithm is to learn to discriminate between data distributed on two distinct strands in the x-y *** problem is of critical importance since it incorporates temporal characteristics often found in real-time *** work with this benchmark has witnessed poor results with statistical methods such as discriminant analysis and tedious procedures for better results with neural *** paper presents a max-density covering learning algorithm based on constructive neural networks which is efficient in terms of the recognition rate and the speed of *** results show that it is possible to solve the spiral problem instantaneously(up to 100% correct classification on the test set).

关键词： pattern recognition neural networks max-density covering learning 2D spiral data

A variational solution of 2-D sound-structure interaction problems

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Acta Mechanica Sinica 2006年第2期22卷 127-131页

作者： Yuying Huang Haidong Su Yu Xiang dept of MechanicsHuazhong University of Science & Technologyuhan 430074 China dept. of Automotive Engineering Guangxi University of Technologyuzhou 545006 China

Based on the fluid-structure coupling theory, a localized variational principle for analyzing the sound radiation from elastic structure submerged in water due to harmonic excitations is presented. It will be a powerful tool to formulate various numerical methods for steady response of structural-acoustic systems. By means of this variational principle a hybrid element method, in which an analytical solution valid in most of the surrounding water is incorporated with finite elements distributed in the structure and its neighboring water, is devised. Computational examples are then given to demonstrate its high accuracy and time saving.

关键词： Variational principle Acoustic radiation Fluid-structure coupling vibration Hybrid element method

Interfacial Microstructure of Diffusion Bonded Inconel 738 and Ferritic Stainless Steel Couple

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Journal of Materials Science & Technology 2009年第4期25卷 527-530页

作者： Bulent Kurt Mustafa Ulutan Bartin University Faculty of EngineeringDept.of Metallurgical and Materials Engineering University of Eskisehir Osmangazi Faculty of EngineeringDept. of Mech.Eng

In this study, Inconel 738 alloy was diffusion bonded to a ferritic stainless steel. The effect of bonding temperature on the microstructural development across the joint region was investigated. Following the diffusion bonding, conventional characterization techniques such as scanning electron microscopy （SEM）, energy dispersive X-ray （EDX） and microhardness were used to examine the interracial microstructure. It was seen that bonding temperature was effective on the diffusion of Ni from Inconel 738 to ferritic stainless steel that affected the microstructure of the interface. Austenite phase was formed at the interface as a result of Ni diffusion from the Inconel 738 to the interface.

关键词： Diffusion bonding Inconel 738 Ferritic stainless steel Interface

Effects of Gd^(3+) on Luminescence Properties of Eu^(3+) within Polymeric Structure in Aqueous Solutions

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Journal of Rare Earths 2001年第1期19卷 11-14页

作者：尹显洪史华红陈小明古练权 Zhongshan Univ Dept Chem Guangzhou 510275 Peoples R China Guangxi Univ Nationalities Dept Chem Nanning 530006 Peoples R China

?6′ tetracarboxy 4,4′ bipyridine was synthesized and the luminescence enhancement of their Eu 3+ complexes by Gd 3+ was observed. The results indicate that the mechanism of enhancement is based on the formation of a polymeric structure where Eu 3+ and Gd 3+ are linked together by the ligands, which favours the consequent transfer of absorbed energy along the polymeric chain through several ligands toward the Eu 3+ .

关键词： rare earths europium complex intramolecular energy transfer co luminescence