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On factorizable solution of the differential equation(f')~2-a_0(z)(f-a)1(z))~2f

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chinese Science Bulletin 1997年第21期42卷 1779-1782页

作者： YUAN Wenjun and HE Yuzaninstitute of mathematics, chinese academy of sciences, beijing 100080, china institute of mathematics Chinese Academy of Sciences Beijing 100080 China

If the coefficients are transcendental, Bergweiler et al. proved that in all possible non-trivialfactorization f(z)=h(g(z)), the growth of the right factor g(z) can be controlled by thegrowth of the coefficients. In ref. [2], He and Laine proved a similar conclusion for two othertypical kinds of nonlinear differential equations. But for the following equation:

关键词： factorization growth order meromorphic function ordinary differential equation.

The asymptotic stability of multistep multiderivative methods for systems of delay differential equations

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Communications in Nonlinear Science and Numerical Simulation 2000年第1期5卷 24-26页

作者： Chengming HUANG and Qianshun CHANG institute of applied mathematics, chinese academy of sciences, P. O. Box 2734, beijing 100080, china institute of applied mathematics Chinese Academy of Sciences P. O. Box 2734 Beijing 100080 China

This paper deals with the asymptotic stability of multistep multiderivative methods for systems of delay differential equations. In particular, it is shown that A-stability of multistep multiderivative methods for ord... 详细信息

关键词： delay differential equation stability multistep multiderivative methods

ON THE ERROR ESTIMATE OF LINEAR FINITE ELEMENT APPROXIMATION TO THE ELASTIC CONTACT PROBLEM WITH CURVED CONTACT BOUNDARY

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Journal of Computational mathematics 2000年第6期18卷 561-566页

作者： Lie-heng Wang (State Key Laboratory of Scientific and Engineering Computing, institute of Computational mathematics, academy of mathematics and System sciences, chinese academy of sciences, beijing 100080, china) 中科院计算数学所科学与工程计算国家重点实验室北京 100080

In this paper, the linear finite element approximation to the elastic contact problem with curved contact boundary is considered. The error bound O(h[sup ?]) is obtained with requirements of two times continuously differentiable for contact boundary and the usual regular triangulation, while *** et. al. Obtained the error bound O(h[sup ?]) with requirements of three times continuously differentiable for contact boundary and extra regularities of triangulation (c.f. [2]). [ABSTRACT FROM AUTHOR]

关键词： contact problem finite element approximation

Adaptive computation for convection dominated diffusion problems

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Science china mathematics 2004年第z1期47卷 22-31页

作者： CHEN Zhiming & Jl GuanghuaLSEC, institute of Computational mathematics, academy of mathematics and System sciences, chinese academy of sciences, beijing 100080, china institute of Computational mathematics, academy of mathematics and System sciences, chinese academy of sciences, beijing 100080, china (email:ghji@***) 1. LSEC Institute of Computational Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 2. institute of Computational mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China

We derive sharp L∞(L1) a posteriori error estimate for the convection dominated diffusion equations of the formThe derived estimate is insensitive to the diffusion parameter ε→0. The problem is dis-cretized implicitly in time via the method of characteristics and in space via continuous piecewise linear finite elements. Numerical experiments are reported to show the competitive behavior of the proposed adaptive method.

关键词： a posteriori error estimator, characteristics, adaptive.

MULTIVARIATE FOURIER SERIES OVER A CLASS OF NON TENSOR-PRODUCT PARTITION DOMAINS

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Journal of Computational mathematics 2003年第1期21卷 53-62页

作者： Jiachang Sun(Parallel Computing Division, institute of Software, chinese academy of sciences, beijing 100080, china) Parallel Computing Division Institute of Software Chinese Academy of Sciences 北京 100080

This paper finds a way to extend the well-known Fourier methods, to so-called n+1 directions partition domains in n-dimension. In particular, in 2-D and 3-D cases, we study Fourier methods over 3-direction parallel hexagon partitions and 4-direction parallel parallelogram dodecahedron partitions, respectively. It has pointed that, the most concepts and results of Fourier methods on tensor-product case, such as periodicity,orthogonality of Fourier basis system, partial sum of Fourier series and its approximation behavior, can be moved on the new non tensor-product partition case.

关键词： Multivariate Fourier methods Non tensor-product partitions Multivariate Fourier series

Stability of proton and maximally symmetric minimal unification model for basic forces and building blocks of matter

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 303-310页

作者： WU YueLiang institute of Theoretical Physics, chinese academy of sciences, beijing 100080, china 1. institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China

With the hypothesis that all independent degrees of freedom of basic building blocks should be treated equally on the same footing and correlated by a possible maximal symmetry, we arrive at a 4-dimensional space-time unification model. In this model the basic building blocks are Majorana fermions in the spinor repre- sentation of 14-dimensional quantum space-time with a gauge symmetry GM4D = SO(1,3)×SU(32)×U(1)A×SU(3)F. The model leads to new physics including mirror particles of the standard model. It enables us to issue some fundamental questions that include: why our living space-time is 4-dimensional, why parity is not con- served in our world, how the stability of proton is, what the origin of CP violation is and what the dark matter can be.

关键词： gauge symmetry space-time symmetries beyond standard model and unification

A SQP Method for Inequality Constrained Optimization

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Acta Mathematicae Applicatae Sinica 2002年第1期18卷 77-84页

作者： Ju-liang ZHANG, Xiang-sun ZHANGinstitute of applied mathematics, academy of mathematics and System sciences, chinese academy of sciences, beijing 100080, china institute of applied mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China

In this paper, a new SQP method for inequality constrained optimization is proposed and the global convergence is obtained under very mild conditions.

关键词： SQP method global convergence inequality constrained optimization nondifferentiable exact penalty function

A new approach of cascade utilization of the chemical energy of fuel

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Progress in Natural Science:Materials International 2006年第5期16卷 518-523页

作者： HAN Wei, JIN Hongguang and LIN Rumou ( institute of Engineering Thermophysics, chinese academy of sciences, beijing 100080, china Graduate School of the chinese academy of sciences, beijing 100080, china) [a]institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China [b]Graduate School of the chinese academy of sciences Beijing China

The indirect release of chemical energy of fuel is investigated, and a new mechanism is proposed to identify the cascade utilization of chemical energy of fuel more clearly. Based on the concept of energy level, the internal phenomenon of the indirect chemical energy release is disclosed, and the equations of energy level describing the utilization of chemical energy and thermal energy during the indirect chemical energy release process are obtained. From theoretical analysis, we find that the superiority of the indirect chemical energy release of fuel comes from the cascade utilization of the fuel's chemical energy. Moreover, the cascade utilization of chemical energy is verified by the investigation of CRGT (chemically recuperated gas turbine). As a result, the thermal exergy obtained from the chemical energy release of fuel increases by 2 % -3 % . The results obtained here may help a deeper understanding of indirect chemical energy release of fuel and provide a theoretical basis for the synthesis of innovative energy systems.

关键词： chemically recuperated gas turbine methane/steam reforming chemical energy level cascade utilization.

STRANGE ATTRACTORS ON PSEUDOSPECTRAL SOLUTIONS FOR DISSIPATIVE ZAKHAROV EQUATIONS1

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Acta Mathematica Scientia 2004年第3期24卷 321-336页

作者： MaShuqing ChangQianshun instituteofappliedmathematics theChineseAcademyofSciencesBeijing100080China

In this paper, the pseudospectral method to solve the dissipative Zakharov equations is used. Its convergence is proved by priori estimates. The existence of the global attractors and the estimates of dimension are presented. A class of steady state solutions is also disscussed. The numerical results show that if the steady state solutions satisfy some special conditions, they become unstable and limit cycles and strange attractors will occur for very small *** largest Lyapunov exponent and analysis of the linearized system are applied to explain these phenomena.

关键词： strange attractors psendospectral method Zakharov equations