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On the ratio of different norms of caloric functions and related eigenfunctions of an integral operator

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science china{2. 2012年第8期55卷 1597-1612页

作者： DING yuTao 1,2.& ZHANG LiQun 1,2.1 Institute of mathematics,{2. of mathematics and systems science,chinese {2. of sciences,Beijing 100190,china 2.hua Loo-Keng Key Laboratory of mathematics,chinese {2. of sciences,Beijing 100190,china 1. Institute of mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China2. Hua Loo-Keng Key Laboratory of Mathematics Chinese Academy of Sciences Beijing 100190 China

We investigate the ratio of L 1 and L 2.norms of the Cauchy problem solutions of heat equations with compact support initial *** related asymptotic behavior of the eigenvalues and eigenfunctions of certain integral op... 详细信息

关键词： integral operators eigenvalues heat equation

Note on families of semistable curves over P^1 with 4 singular fibers whose Jacobian are non-compact

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science china{2. 2010年第7期53卷 1710-1713页

作者： yu Fei 1, 2.1 academy of mathematics and systems science,{2., Beijing 100190, china 2.Department of mathematics, East china Normal University, Shanghai 2.0062. china academy of mathematics and{2. science Chinese Academy of Sciences Beijing China Department of mathematics East China Normal University Shanghai China

Let f : S → P 1 be a semistable family of curves of genus g 2. We prove that if f admits exactly 5 singular fibers and 4 of them have non-compact Jacobian, then g = 2.

关键词： singular fiber adjoint linear system non-compact Jacobian

Admissibilities of linear estimator in a class of linear models with a multivariate t error variable

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science china{2. 2010年第8期53卷 2011-2019页

作者： YANG GuoQing 1 & WU QiGuang 2.1 Department of mathematics,Tongji University,Shanghai 2.0092.china 2.Institute of{2. science,academy of mathematics and{2. science,chinese academy of sciences,Beijing 100190,china 1. Department of mathematics Tongji University Shanghai 200092 China2. Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

This paper discusses admissibilities of estimators in a class of linear models,which include the following common models:the univariate and multivariate linear models,the growth curve model,the extended growth curve model,the seemingly unrelated regression equations,the variance components model,and so *** is proved that admissible estimators of functions of the regression coefficient β in the class of linear models with multivariate t error terms,called as Model II,are also ones in the case that error terms have multivariate normal distribution under a strictly convex loss function or a matrix loss *** is also proved under Model II that the usual estimators of β are admissible for p 2.with a quadratic loss function,and are admissible for any p with a matrix loss function,where p is the dimension of β.

关键词： multivariate t distribution convex loss quadratic loss matrix loss admissible estimator

Markov chain approach to identifying Wiener systems

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science china(Information{2.) 2012年第5期55卷 1201-1217页

作者： ZHAO WenXiao 1,2.& CHEN HanFu 1,2.1 Key Laboratory of systems and Control,Institute of systems{2.,AMSS,chinese academy of sciences,Beijing 100190,china 2.National Center for mathematics and Interdisciplinary sciences,chinese academy of sciences,Beijing 100190,china 1. Key Laboratory of systems and Control Institute of Systems Science AMSS Chinese Academy of Sciences Beijing 100190 China2. National Center for Mathematics and Interdisciplinary Sciences Chinese Academy of Sciences Beijing 100190 China

Identification of the Wiener system composed of an infinite impulse response (IIR) linear subsystem followed by a static nonlinearity is *** recursive estimates for unknown coefficients of the linear subsystem and for the values of the nonlinear function at any fixed points are given by the stochastic approx-imation algorithms with expanding truncations (SAAWET).With the help of properties of the Markov chain connected with the linear subsystem,all estimates derived in the paper are proved to be strongly *** comparison with the existing results on the topic,the method presented in the paper simplifies the convergence analysis and requires weaker conditions.A numerical example is given,and the simulation results are consistent with the theoretical analysis.

关键词： Wiener system recursive identification stochastic approximation Markov chain strong consis-tency

On the local wellposedness of 3-D water wave problem with vorticity

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science china{2. 2007年第8期50卷 1065-1077页

作者： Ping ZHANG~1 Zhi-fei ZHANG~2.1 academy of mathematics and systems science,chinese{2. of sciences,Beijing 100080,china 2.School of Mathematical sciences,Peking University,Beijing 100871,china academy of mathematics systems science Chinese Academy of Sciences Beijing 100080 China School of Mathematical sciences Peking University Beijing 100871 China

In this article, we first present an equivalent formulation of the free boundary problem to 3-D incompressible Euler equations, then we announce our local wellposedness result concerning the free boundary problem in Sobolev space provided that there is no self-intersection point on the initial surface and under the stability assumption that $\frac{{\partial p}}{{\partial n}}(\xi )\left| {_{t = 0} } \right. \leqslant - 2._0 < 0$ being restricted to the initial surface.

关键词： water-waves free boundary incompressible Euler equations primary 35Q35 76B03 secondary 35J67 35L80

A class of additive-accelerated means regression models for recurrent event data

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science china{2. 2010年第12期53卷 3139-3151页

作者： LIU Li 1, MU Xiaoyun 2.& SUN LiuQuan 2.1 School of mathematics and Statistics, Wuhan University, Wuhan 430072.{2. 2.Institute of Applied mathematics, academy of mathematics and systems science, chinese academy of sciences, Beijing 100080,{2. 1. School of mathematics and Statistics Wuhan University Wuhan 430072 China2. Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

In this article, we propose a class of additive-accelerated means regression models for analyzing recurrent event data. The class includes the proportional means model, the additive rates model, the accelerated failure time model, the accelerated rates model and the additive-accelerated rate model as special cases. The new model offers great flexibility in formulating the effects of covariates on the mean functions of counting processes while leaving the stochastic structure completely unspecified. For the inference on the model parameters, estimating equation approaches are derived and asymptotic properties of the proposed estimators are established. In addition, a technique is provided for model checking. The finite-sample behavior of the proposed methods is examined through Monte Carlo simulation studies, and an application to a bladder cancer study is illustrated.

关键词： additive-accelerated means model counting process marginal model model checking recurrent events

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.,Beijing 100080,china 2.4},chinese academy of{2.,Beijing 100080,china 3 Graduate University of chinese academy of sciences,Beijing 100080,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

Study on the generator f of the operators I_n and I_t

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science china{2. 2010年第10期53卷 2589-2603页

作者： CHEN HanLin academy of mathematics and systems science,chinese{2. of sciences,Beijing 100190,china 1. academy of mathematics and systems science Chinese Academy of Sciences Beijing 100190 China

Define two operators In and It,the inner product operator In(g)(x) := j∈Zs(g,f(·-j))f(x-j) and the interpolation operator It(g)(x) := j∈Zs g(j)f(x-j),where f belongs to some space and integer s *** call f the generator of the operators In and *** is well known that there are many results on operators In and *** there remain some important problems to be further *** application we first need to find the available generators (that can recover polynomials as It(p) = p or In(p) = p,p ∈Πm-1) for constructing the relative *** this paper,we focus on the available generator in the class of spline *** shall see that not all spline functions can be used to construct available ***,we do find a spline function in S,of degree m-1,where m is even and S is a class of *** for odd m the problem is still *** on spline functions in this paper are new.

关键词： generator available generator inner product operator spline interpolation operator two-closed refinable

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 systems science, chinese academy of sciences, Beijing 100080,{2. 2. Institute of Computing Technology, chinese academy of sciences, Beijing 100080,{2. 3. Institute of Software, chinese academy of sciences, Beijing 100080,{2. 4. Graduate University of chinese academy of sciences, Beijing 100049,{2. 1. academy of mathematics and systems science 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 sciences 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.