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Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science China Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3.& WANG Huijun2.1. Nansen-Zhu International Research Center, institute of Atmospheric Physics,{3., {2. 10002., China 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, China 3. Graduate University of the{3., {2. 100049, China Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science Yunnan University Kunming China Graduate University of the chinese academy of sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

STUDY ON THE SYNTHESIS AND PROPERTIES OF POLY(ESTER-IMIDEETHER)MULTIBLOCK COPOLYMERS

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chinese Journal of Polymer Science 2000年第1期18卷 9-13页

作者： Zu-yao Shan Zhen-yi Li institute of Chemistry, chinese academy of sciences,{2., China 中科院化学所北京

A new class of poly(ester-imide-ether) multiblock copolymers was synthesized by transes-terification and melt copolymerization of dimethyl terephthalate (DMT) and N-(4-carbomethoxyphenyl)-4-(carbomethoxy)-phthalimide with ethylene glycol (EG) and polytetramethylene glycol (PTMG). The structure of the above copolymers was characterized by H-1-NMR and IR spectroscopy. Some properties of the coplymers were also examined. It was found that their mechanical properties and heat stability, compared with poly(ether-ester) copolymers, were obviously improved.

关键词： N-(4-carbomethoxyphenyl)-4-(carbomethoxy)-phthalimide polyester-polyether copolymer poly-(ester-imidether) multiblock copolymer imide modification

Attractors and Dimensions for Discretizations of a Dissipative Zakharov Equations

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Acta Mathematicae Applicatae Sinica 2002年第2期18卷 201-214页

作者： Qian-shun Chang, Bo-ling Guoinstitute of applied {2.,{3. of {2. and System sciences, chinese academy of sciences,beijing 100080, Chinainstitute of applied Physics and Computational {2., beijing 100088, China institute of applied {2. Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China institute of applied Physics and Computational {2. Beijing China

In this paper, a dissipative Zakharov equations are discretized by difference method. We make prior estimates for the algebric system of equations. It is proved that for each mesh size, there exist attractors for the discretized system. The bounds of the Hausdorff dimensions of the discrete attractors are obtained, and the various bounds are dependent of the mesh sizes.

关键词： Attractor dissipative Zakharov equation

Y_CΩ_(2.)are easy terms

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chinese Science Bulletin 1998年第20期43卷 1707-1709页

作者： ZHAO Xishun 1 and WANG Ju 2.1. Department of mathematics, Nanjing University, Nanjing 2.0093. China 2. institute of Software,{2., beijing 100080, China Department of mathematics Nanjing University Nanjing China institute of Software Chinese Academy of Sciences Beijing China

For any natural number n≥1, Y CΩ 2. is an easy term; that is, for any λ term M, λβ+Y\-CΩ 2. =M is consistent, where Y C is Curry fixed point combinator, Ω 2. ≡ω 2. ω 2. and ω 2. ≡λ***...x (there are 2. occurrences of x after λx ). This result is a partial solution to Jacopini’s conjecture: Y CΩ n is an easy term for any natural number n≥2.

关键词： λβ-calculus Kuper’s theorem easy term.

VARIABLE SELECTION BY PSEUDO WAVELETS IN HETEROSCEDASTIC REGRESSION MODELS INVOLVING TIME SERIES

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Acta Mathematica Scientia 2006年第3期26卷 469-476页

作者：王清河周勇 Department of applied mathematics University of Petroleum Shandong 257062China institute of applied {2.{3. of {2. and Systems Science The chinese academy of sciences Beijing 100080China

A simple but efficient method has been proposed to select variables in heteroscedastic regression models. It is shown that the pseudo empirical wavelet coefficients corresponding to the significant explanatory variables in the regression models are clearly larger than those nonsignificant ones, on the basis of which a procedure is developed to select variables in regression models. The coefficients of the models are also estimated. All estimators are proved to be consistent.

关键词： Heteroscedastic regression models variable selection wavelets

ANALYSIS OF A PRODUCTION-INVENTORY MODEL WITH ERLANGIAN DEMAND ARRIVAL PROCESS

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Journal of Systems Science & Complexity 2003年第2期16卷 184-190页

作者： WANG Jinting CAO Jinhua LIU Bin(institute of applied {2.,{3. of {2. and Systems sciences, chinese academy of sciences, beijing 100080, China) institute of applied {2. Academy of Mathematics and Systems Sciences Chinese Academy of Sciences 北京 100080

We study a production-inventory system having a machine, a storage facility. The demand for the product is governed by an Erlangian demand arrival process, where demand sizes are independent and identically distributed random variables. A two-criticalnumber policy (m, M) is used to control a machine's setups and shutdowns, namely, a machine is shut down whenever the inventory level reaches M, and resumes operating only when the inventory level falls below the critical number m(m ≤ M). We obtain the steady state distribution of the inventory process and some performance measures of the process.

关键词： erlangian demand arrival process production-inventory system

Algebraic Independence by Approximation Method(Ⅱ)

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Acta Mathematica Sinica,English Series 2000年第3期16卷 395-398页

作者： Yaochen Zhu institute of applied {2.,{3. of {2. and Systems sciences,Academia Sinica,beijing 100080,P.R.China Fax:010-62.41689 institute of applied {2. Academy of Mathematics and Systems Sciences Academia Sinica Beijing 100080 P. R. China

Let f（x）be a continued fraction with elements anx,where coefficients an are positive alge- braic *** the criterion of[1]for any nonzero real algebraic numbers α1,...,αs with distinct absolute values the algebraic independence of the values f（α1）,...,f（αs）is proved under certain as- sumption concerning only with an.For some transcendental numbers ζ the algebraic independence of values f（ζj）（j∈Z）is also established.

关键词： Algebraic independence Continued fraction Approximation method

Monomial Hopf algebras over fields of positive characteristic

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Science China mathematics 2006年第3期49卷 320-329页

作者： LIU Gongxiang & YE Yu institute of mathematics, {2. of mathematics and Systems Science, chinese academy of sciences, beijing 100080, China Department of mathematics, University of Science and Technology of China, Hefei 2.002., China institute of mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Department of mathematics University of Science and Technology of China Hefei China

In this paper, we study the structures of monomial Hopf algebras over a field of positive characteristic. A necessary and sufficient condition for the monomial coalgebra Cd(n) to admit Hopf structures is given here, and if it is the case, all graded Hopf structures on Cd(n)are completely classified. Moreover, we construct a Hopf algebras filtration on Cd(n) which will help us to discuss a conjecture posed by Andruskiewitsch and Schneider. Finally combined with a theorem by Montgomery, we give the structure theorem for all monomial Hopf algebras.

关键词： monomial coalgebra, Gaussian binomial coefficient, monomial Hopf algebra.

Scheme construction with numerical flux residual correction (NFRC) and group velocity control (GVC)

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Progress in Natural Science:Materials International 2006年第12期16卷 1252-1259页

作者： MA Yanwen **and FU Dexun(LNM, institute of Mechanics, chinese academy of sciences,{2., China) LNM Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

For simulating multi-scale complex flow fields like turbulent flows, the high order accurate schemes are preferred. In this paper, a scheme construction with numerical flux residual correction (NFRC) is presented. Any order accurate difference approximation can be obtained with the NFRC. To improve the resolution of the shock, the constructed schemes are modified with group velocity control (GVC) and weighted group velocity control (WGVC). The method of scheme construction is simple, and it is used to solve practical problems.

关键词： high order accurate scheme group velocity control high resolution of the shock.