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CONVERGENCE AND SUPERCONVERGENCE OF HERMITE BICUBIC ELEMENT FOR EIGENVALUE PROBLEM OF THE BIHARMONIC EQUATION

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Journal of Computational mathematics 2001年第2期19卷 139-142页

作者： Dong-sheng Wu (Institute of systems science, {2. of {3. and systems sciences, chinese {2. of sciences, beijing 100080, China ) 中科院系统科学所北京 100080

Provides information on a study which discussed the convergence and superconvergence for eigenvalue problem of the biharmonic equation using the Hermite bicubic element. Discussion on eigenvalue problem for biharmonic equation; Background on asymptotic error expansions and interpolation postprocessing; Superconvergence approximations to the eigenvalue and eigenfunction.

关键词： Hermite bicubic element biharmonic equation interpolation postprocessing eigenvalue problem

Review on the study of entanglement in quantum computation speedup

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chinese science Bulletin 2007年第16期52卷 2161-2166页

作者： DING ShengChao1,3.& JIN Zhi1,2.1 Institute of Computing Technology,chinese academy of {2.s,{3.,China 2.academy of mathematics and systems science,chinese academy of {2.s,{3.,China 3.Graduate University of chinese academy of {2.s,{3.,China Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China

The role the quantum entanglement plays in quantum computation speedup has been widely disputed. Some believe that quantum computation's speedup over classical computation is impossible if entan-glement is absent,while others claim that the presence of entanglement is not a necessary condition for some quantum algorithms. This paper discusses this problem systematically. Simulating quantum computation with classical resources is analyzed and entanglement in known algorithms is reviewed. It is concluded that the presence of entanglement is a necessary but not sufficient condition in the pure state or pseudo-pure state quantum computation speedup. The case with the mixed state remains open. Further work on quantum computation will benefit from the presented results.

关键词：量子论量子纠缠量子计算加速模拟

Modeling and verifying Web services driven by requirements:An ontology-based approach

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science in China(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3.JIN ZHi1,2.& WU Budan1,4 1. academy of mathematics and {2. {3., chinese academy of {3.s, beijing 100080, China 2. Institute of Computing Technology, chinese academy of {3.s, beijing 100080, China 3. Institute of Software, chinese academy of {3.s, beijing 100080, China 4. Graduate University of chinese academy of {3.s, beijing 100049, China 1. academy of mathematics and {2. {3. Chinese Academy of Sciences Beijing 100080 China 3. Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. Institute of Computing Technology Chinese Academy of Sciences Bejing 100080 China 4. Graduate University of chinese academy of {2.s Beijing 100049 China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

Quasi-likelihood estimation of average treatment effects based on model information

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science China mathematics 2007年第1期50卷 1-12页

作者： Zhi-hua SUN academy of mathematics and {2. {3., chinese academy of {3., beijing 100080, China 1. academy of mathematics and {2. {3. Chinese Academy of Science Beijing 100080 China

In this paper, the estimation of average treatment effects is considered when we have the model information of the conditional mean and conditional variance for the responses given the covariates. The quasi-likelihood method adapted to treatment effects data is developed to estimate the parameters in the conditional mean and conditional variance models. Based on the model information, we define three estimators by imputation, regression and inverse probability weighted methods. All the estimators are shown asymptotically normal. Our simulation results show that by using the model information, the substantial efficiency gains are obtained which are comparable with the existing estimators.

关键词： average treatment effects inverse probability weighted quasi-likelihood unconfounded assignment treatment model information 62.18

BOUNDARY FEEDBACK STABILIZATION OF NONUNIFORM TIMOSHENKO BEAM WITH A TIPLOAD

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chinese Annals of mathematics,Series B 2001年第4期22卷 485-494页

作者： YAN QINGXU, FENG DEXING Institute of systems science, {2. of {3. and systems science, chinese {2. of sciences, beijing 100080, China. Institute of systems science, {2. of {3. and systems science, chinese {2. of sciences, Be Institute of systems science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

The boundary stabilization problem of a Timoshenko beam attached with a mass at one end is studied. First, with linear boundary force feedback and moment control simultaneously at the end attached with the load, the energy corresponding to the closed loop system is proven to be exponentially convergent to zero as time t →∞. Then, some counterexamples are given to show that, in other casest the corresponding closed loop system is, in general, not stable asymtotically, let alone exponentially.

关键词： Timoshenko beam Boundary feedback control C0 semigroups Exponential stability Multiplier method

A quasi-local mass for 2.spheres with negative Gauss curvature

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science China mathematics 2008年第9期51卷 1644-1650页

作者： ZHANG Xiao Institute of mathematics, academy of mathematics and {3. science, chinese academy of sciences, beijing 100080, China 1. Institute of mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

We extend our previous definition of quasi-local mass to 2.spheres whose Gauss curvature is negative, and prove its positivity.

关键词： general relativity quasi-local mass positivity 53.2. 53.50 83.60

A CLASS OF NEW PARALLEL HYBRID ALGEBRAIC MULTILEVEL ITERATIONS

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Journal of Computational mathematics 2001年第6期19卷 651-672页

作者： Zhong-zhi Bai (LSEC ICMSEC, academy of mathematics and {2. {3.s, chinese academy of {3.s, beijing 100080, China) 中科院计算数学与科学工程计算所北京 100080

Presents preconditioning matrices having parallel computing function for the coefficient matrix and a class of parallel hybrid algebraic multilevel iteration methods for solving linear equations. Solution to elliptic ... 详细信息

关键词： elliptic boundary value problem system of linear equations symmetric positive definite matrix multilevel iteration parallel method

A trust region algorithm for bilevel programing problems

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chinese science Bulletin 1998年第10期43卷 820-824页

作者： LIU Guoshan 1, HAN Jiye 2.and WANG Shouyang 3.1. Department of mathematics, beijing Normal University, beijing 100875, China 2. Institute of Applied mathematics, chinese academy of sciences, beijing 100080, China 3. Institute of systems science, Chi Department of mathematics Beijing Normal University Beijing China Institute of Applied mathematics Chinese Academy of Sciences Beijing China Institute of systems science Chinese Academy of Sciences Beijing China

A trust region algorithm is proposed for solving bilevel programming problems where the lower level programming problem is a strongly convex programming problem with linear constraints. This algorithm is based on a tr... 详细信息

关键词： bilevel programming problem trust region algorithm global convergence.

CONVERGENCE OF NONLINEAR CONJUGATE GRADIENT METHODS

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Journal of Computational mathematics 2001年第5期19卷 539-548页

作者： Yu-hong Dai (LSEC, ICMSEC, academy of mathematics and {2. {3.s, chinese academy of {3.s,beijing 100080, China) 中科院计算数学与科学工程计算所北京 100080

Presents a study on methods for unconstrained optimization. Assumptions of the study; Main results; Convergence properties of the methods under simplified Armijo-type line search.

关键词： unconstrained optimization conjugate gradient (generalized) line search global convergence