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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. sciences, Chinese academy of sciences, 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

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. science, Chinese academy of sciences, beijing 100080, china 2. Institute of Computing Technology, Chinese academy of sciences, beijing 100080, china 3. Institute of software, Chinese academy of sciences, beijing 100080, china 4. Graduate University of Chinese academy of sciences, beijing 100049, china academy of mathematics and {2. science Chinese Academy of Sciences Beijing China Institute of software Chinese Academy of Sciences Beijing China Institute of Computing Technology Chinese Academy of Sciences Bejing China Graduate University of Chinese academy of sciences Beijing 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.

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. sciences, Chinese academy of sciences,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

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 sciences,beijing {2.,china 2.academy of mathematics and systems science,Chinese academy of sciences,beijing {2.,china 3.Graduate University of Chinese academy of sciences,beijing {2.,china Institute of Computing Technology Chinese Academy of Sciences Beijing China Graduate University of Chinese academy of sciences Beijing China academy of mathematics and {2. science Chinese Academy of Sciences Beijing 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

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, academy of {2. and systems sciences, Chinese academy 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

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.

Fiducial inference in the pivotal family of distributions

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science china mathematics 2006年第3期49卷 410-432页

作者： XU Xingzhong & LI Guoying Department of mathematics, beijing Institute of Technology, beijing 100081,{3. academy of mathematics and systems science, Chinese academy of sciences, beijing 100080,{3. Department of mathematics Beijing Institute of Technology Beijing China academy of mathematics and {2. science Chinese Academy of Sciences Beijing China

In this paper a family, called the pivotal family, of distributions is considered.A pivotal family is determined by a generalized pivotal model. Analytical results show that a great many parametric families of distributions are pivotal. In a pivotal family of distributions a general method of deriving fiducial distributions of parameters is proposed. In the method a fiducial model plays an important role. A fiducial model is a function of a random variable with a known distribution, called the pivotal random element, when the observation of a statistic is *** method of this paper includes some other methods of deriving fiducial distributions. specially the first fiducial distribution given by Fisher can be derived by the method. For the monotone likelihood ratio family of distributions, which is a pivotal family, the fiducial distributions have a frequentist property in the Neyman-Pearson view. Fiducial distributions of regular parametric functions also have the above frequentist property. some advantages of the fiducial inference are exhibited in four applications of the fiducial distribution. Many examples are given, in which the fiducial distributions cannot be derived by the existing methods.

关键词： confidence bounds, fiducial distributions, fiducial model, frequentist prop-erty, generalized pivotal model, pivotal family of distributions, testing hypotheses.

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 Institute of mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 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

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. science, Chinese academy of science, beijing 100080, china academy of mathematics and {2. science Chinese Academy of Science Beijing 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