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Chinese Science Bulletin 2000年第1期45卷 11-18页

作者： Shuni Song Xianghua Liu Guodong Wang Northeastern Univ State Key Lab Rolling & Automat Shenyang 110006 Peoples R China

The total power rate functional for hot rolling problem with the rigid-plastic SCM model is considered. The gradient operator of the plastic deformation power rate functional is deduced. it is strictly monotone mapping. Further, it is proved that the frictional power rate functional is a convex functional and the tensional stress power rate functional is a linear one. Hence, the total power rate functional is a strictly convex functional. By using nonlinear functional analysis methods, the existence and uniqueness of extreme point.of the functional is obtained.

关键词： slightly compressible material (SCM) rolling total power rate functional strictly convex functional extreme point.

Essential point.set of convolution power of a probability measure on locally compact topological semigroup

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Chinese Science Bulletin 1995年第14期40卷 1155-1159页

作者：刘锦萼房俊岭俞绍宏 Department of Statistics Shandong Institute of Economics Jinan 250014 China Department of Mathematics and Physics Shandong University of Technology Jinan 250014 China

Many authors have studied the limit hehavior of the sequence of probability measureon a topological group or *** to the description of the limit behavior of the sequence by the essential point.setof the convolution sequence, Maximov studied the case of compact topologica1 group. Inthis note, the problem of weak convergence for the sequence of convolution power of aprobability measure is considered on the locally compact topological semigroup. Jn particu-lar. the relation between the essential point.set of the sequence and the support set of theweak limit of the sequence is studied.

关键词： locally compact semigroup probability measure completely simple semigroup essential point.

Necking point.in PET High-speed Fiber Spinning

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Journal of Donghua University(English Edition) 2001年第1期18卷 16-20页

作者： Wang Xiaqin(王夏琴) Tang Zhilian(唐志廉) College of Environmental Science & Engineering Dong Hua University Shanghai 200051 College of Environmental Science & Engineering Dong Hua University Shanghai 200051

Cross-over method is established to predict necking point.for PET high- speed fiber spinning. Even slowly crystallizing polymers such as PET can crystallize on the spinline at sufficiently high spinning speed. The development of rtmning velocity, temperature, crystallinity and theological force is investigated for the take-up velocity over a range of 6 000 - 10 000 m/min. The position of necking point. temperature rise and abrupt increase of crystallinity move closer to the spinneret with the increase of take-up velocity,

关键词： PET high-speed spinning, Simulation, necking point.

THEORY OF VALUES OF SINGULAR point.IN COMPLEX AUTONOMOUS DIFFERENTIAL SYSTEMS

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Science China Mathematics 1990年第1期33卷 10-23页

作者：刘一戎李继彬 Hunan University Changsha 410082 PRC Kunming Institute of Technology Kunming 650093 PRC

Consider the complex autonomous differential system (E). The main results of this paper are as follows: (i) The concept of values of singular point.has been defined. It can realize the unity between the saddle values and the focal values in real systems, (ii) By defining the concept of the Lie-invariant, the constructive theorem of values of singular point.and the extended symmetric principle can be obtained. (iii) All the 120 elementary Lie-invariants of (E3) have been computed. The constructive theorem being used, formulas of values of singular point.and the integrability conditions of (E2) and (E(3)3) have been derived.

关键词： differential systems values of singular point.

The oscillation of the occupation time process of super- Brownian motion on Sierpinski gasket

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Science China Mathematics 2000年第12期43卷 1250-1257页

作者：郭军义 Department of Mathematics Nankai University Tianjin 300071 China

The occupation time process of super-Brownian motion on the Sierpinski gasket is studied. It is shown that this process does not possess stable property in the long run, but oscillates periodically in some sense. Othe... 详细信息

关键词： occupation time process superprocess catalytic point.

Repelling periodic point. of given periods of rational functions

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Science China Mathematics 2006年第9期49卷 1165-1174页

作者： CHANG Jianming FANG Mingliang Department of Mathematics Changshu Institute of Technology Changshu 215500 China Department of Applied Mathematics South China Agricultural University Guangzhou 510642 China

Let R(z) be a rational function of degree d ≥ 2. Then R(z) has at least one repelling periodic point.of given period k ≥ 2, unless k = 4 and d=2, or k= 3 and d ≤ 3, or k=2 and d≤8. Examples show that all exception... 详细信息

关键词： rational function, iterate, fixed point. periodic point. repelling periodic point.

Rock magnetic properties of Nihewan sediments at Xujiayao

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Science China Earth Sciences 2002年第10期45卷 939-948页

作者：王喜生 LφvlieReidar SUPu 苏朴 Institute of Geomechanics Chinese Academy of Geological Sciences Beijing China Institute of Solid Earth Physics Bergen Norway Taiyuan University of Technology Taiyuan China

Rock magnetic measurements of Nihewan sediments from Xujiayao section demonstrate that magnetite, hematite and maghemite are dominant remanent magnetization carriers. Monitoring the variations of magnetic susceptibility(MS) and saturating isothermal remanent magnetization(SIRM) at low temperature are the attractive ways of detecting the presence of magnetite, maghemitization and superparamagnetic grain sizes. Low-temperature MS investigations suggest that susceptibility enhancement for Xujiayao samples is mainly due to the remarkable presence of SD/MD magnetite to some degree though some magnetite grains have been partially oxidized at some depths. It is tentatively concluded that both SD/MD magnetite and hematite are of detrital origin and carry a characteristic remanent magnetization(ChRM), whereas maghemite can be attributed to be chemical origin, overprinting a reversed polarity component of Matuyama age.

关键词： Nihewan, SIRM, hysteresis loops, depositional remanent magnetization, Curie point.

Deformation in locally convex topological linear spaces

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Science China Mathematics 2004年第5期47卷 687-710页

作者： DING Yanheng Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100080 China

We are concerned with a deformation theory in locally convex topological linear spaces. A special 'nice' partition of unity is given. This enables us to construct certain vector fields which are locally Lipschitz continuous with respect to the locally convex topology. The existence, uniqueness and continuous dependence of flows associated to the vector fields are established. Deformations related to strongly indefinite functionals are then obtained. Finally, as applications, we prove some abstract critical point.theorems.

关键词： locally convex topology, deformation, critical point.

On KKT point. of Celis-Dennis-Tapia subproblem

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Science China Mathematics 2006年第5期49卷 651-659页

作者： LI Gaidi College of Applied Sciences Beijing University of Technology Beijing 100022 China

The Celis-Dennis-Tapia(CDT) problem is a subproblem of the trust region algorithms for the constrained optimization. CDT subproblem is studied in this paper. It is shown that there exists the KKT point.such that the Hessian matrix of the Lagrangian is positive semidefinite,if the multipliers at the global solution are not unique. Next the second order optimality conditions are also given, when the Hessian matrix of Lagrange at the solution has one negative *** furthermore, it is proved that all feasible KKT point. satisfying that the corresponding Hessian matrices of Lagrange have one negative eigenvalue are the local optimal solutions of the CDT subproblem.

关键词： CDT subproblem, local solution, optimality condition, saddle point.

On the periodic solutions of a type of differential-iterative equations

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Chinese Science Bulletin 1998年第3期43卷 204-206页

作者： GE Weigao 1, LIU Zhengrong 2 and YU Yuanhong 3 1. Department of Applied Mathematics, Beijing Institute of Technology, Beijing 100081, China 2. Department of Mathematics, Yunnan University, Kunming 650091, China 3. Institute of Applied Mathematics, C Department of Applied Mathematics Beijing Institute of Technology Beijing China Department of Mathematics Yunnan University Kunming China Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

Sufficient conditions for the existence of periodic solutions to a type of nonautonomous differential_iterative equations are given.

关键词： differential_iterative equation periodic solution fixed point.