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Pointwise characterization for combinations of Szász-Mirakjan operators

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Applied Mathematics(A Journal of Chinese univ.rsities) 2008年第2期23卷 202-212页

作者： XIE Lin-sen SHI Zhong-rui Dept. of Math. Shanghai Univ. Shanghai 200444 China Dept. of Math. Lishui Univ. Lishui 323000 China

The purpose of this paper is to characterize the pointwise rate of convergence for the combinations of Szász-Mirakjan operators using Ditzian-Totik modulus of smoothness.

关键词： Szász-Mirakjan operator combination pointwise approximation.

Affinities and functional morphology of the Middle Cambrian ornamented tubules from West Hunan,China

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Progress in Natural Science:Materials International 2004年第10期14卷 67-71页

作者： ZHU Caifa 1,2 and DONG Xiping 1 (1.School of Earth and Space Sciences,Peking univ.rsity,Beijing100871,China 2.univ.rsity of Petroleum,Beijing102249,China) Sch. of Earth and Space Sci. Peking Univ. Beijing 100871 China univ. of Petroleum Beijing 102249 China

Problematic phosphatic tubular microfossils with ornamented sculptures are documented to exist in limestones of the up-per Middle Cambrian Huaqiao Formation at the Paibi section and the Wangcun section in West Hunan,*** morphological pat-terns,including Ornamented Tube Form I and Ornamented Tube Form II are *** on the analysis of the preservation,wall structure and composition of the fossils,it is deduced that these ornamented tubes may represent carapace spines of some Cambrian arthro-pods with phosphatic carapaces,such as bradoriid *** of functional morphology indicates that the sclerites may rather be considered of a defensive than grasping function on the original organism body.

关键词： Middle Cambrian ornamented tubes affinities functional morphology West Hunan

Family genetic algorithms based on gene exchange and its application

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Journal of Systems Engineering and Electronics 2006年第4期17卷 864-869页

作者： Li Jianhua Ding Xiangqian Wang Sun'an Yu Qing Ocean univ. of China Qingdao 2660071P.R.China Xi'an Jiaotong univ. Xi'an 710049 P.R.China

Genetic Algorithms （GA） are a search techniques based on mechanics of nature selection and have already been successfully applied in many diverse areas. However, increasing samples show that GA＇s performance is not as good as it was expected to be. Criticism of this algorithm includes the slow speed and premature result during convergence procedure. In order to improve the performance, the population size and individuals＇ space is emphatically described. The influence of individuals＇ space and population size on the operators is analyzed. And a novel family genetic algorithm （FGA） is put forward based on this analysis. In this novel algorithm, the optimum solution families closed to quality individuals is constructed, which is exchanged found by a search in the world space. Search will be done in this microspace. The family that can search better genes in a limited period of time would win a new life. At the same time, the best gene of this micro space with the basic population in the world space is exchanged. Finally, the FGA is applied to the function optimization and image matching through several experiments. The results show that the FGA possessed high performance.

关键词： genetic algorithms function optimization image matching population size individual space.

NASCS FOR THE ABSOLUTE STABILITY OF LURE DIRECT CONTROL SYSTEMS

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Acta Mathematica Scientia 1989年第1期9卷 75-82页

作者：廖晓昕 Huazhong Normal univ. Wuhan China

In this paper, we transform n-th order Lure direct control systems into nonlinear systems with separating variables, and induce a concept for absolute stability of part arguments. The necessary and sufficient conditions (NASC) for the absolute stability of Lure direct control systems are given and some sufficient conditions are obtained

关键词： NASCS FOR THE ABSOLUTE STABILITY OF LURE DIRECT CONTROL SYSTEMS

Design of a Low Power DSP with Distributed and Early Clock Gating

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Journal of Shanghai Jiaotong univ.rsity(Science) 2007年第5期12卷 610-617页

作者：王兵王琴彭瑞华付宇卓 School of Microelectronics Shanghai Jiaotong Univ.

A novel clock structure of a low-power 16-bit very large instruction word (VLIW) digital signal processor (DSP) was proposed. To improve deterministic clock gating and to solve the drawback of conventional clock gating circuit in high speed circuit, a distributed and early clock gating method was developed on its instruction fetch & decoder unit, its pipelined data-path unit and its super-Harvard memory interface unit. The core was implemented following the Synopsys back-end flow under TSMC (Taiwan Silicon manufacture corporation) 0.18-μm 1.8-V 1P6M process, with a core size of 2 mm×2 mm. Result shows that it can run under 200 MHz with a power performance around 0.3 mW/MIPS. Meanwhile, only 39.7% circuit is active simultaneously in average, compared to its non-gating counterparts.

关键词： digital signal processor (DSP) deterministic clock gating (DCG) distributed and early clock gating low power design pipeline

SYNTHESIS OF ORGANOGERMANE OLIGOMERS VIA LIGAND SUBSTITUTION POLYMERIZATION FROM 1, 4-DIOXANE COMPLEX OF GERMANIUM DICHLORIDE

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Chinese Journal of Polymer Science 1997年第4期15卷 347-352页

作者：曹少魁李晨光郑世军李自法 KOBAYASHI Shiro Department of Materials Engineering Zhengzhou Univ. Zhengzhou 450052 China Graduate School of Engineering Tohoku Univ. Aoba Sendai 980-77 Japan

Some organogermanium oligomers with different side groups were synthesized via ligand substitution polymerization from I, l-dioxane complex of germanium dichloride with different organolithium compounds. The oligomers were isolated through either precipitation from methanol or extraction using toluene with a yield of no less than 50%. The weight average molecular weight (M-w) of the oligomers is ranging from 1.4 x 10(3) to 5.9 x 10(3) depending on the type and alkyl length of the organolithium compounds used.

关键词： organogermanium oligomer polygermane ligand substitution polymerization germanium dichloride organolithium compounds

Effect of Cerium on Corrosion Resistance of Bright Zinc Electrodeposit

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Journal of Rare Earths 1994年第1期12卷 18-22页

作者：李士嘉何建平陈网桦张英 Nanjing univ. of Aeronautics and Astronautics Nanjing China

The effect of cerium on the corrosion resistance of bright zinc coating is investigated in this paper. The corrosion resistance of coating is increased by 35% with the addition of cerous salt (0.10-0.20g/1) into the zinc plating bath solution. Chemical analysis and X-ray diffraction tests show that a trace amount of Ce is present in the deposit which leads to a preferred orientation of the crystal planes. Experiments on several main properties of the bath solution show that the presence of a small amount of cerous salt brings little effect on the base solution.

关键词： Cerium Corrosion resistance Electrodeposition

Density-functional formula for strongly correlated systems

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Progress in Natural Science:Materials International 2005年第5期15卷 395-401页

作者： WANG Huaiyu1*, HAN Rushan2 and CHEN Nanxian1(1. Department of Physics, Tsinghua univ.rsity, Beijing 100084, China 2. Department of Physics, Peking univ.rsity, Beijing 100871, China) Dept. of Phys. Tsinghua Univ. Beijing 100084 China Dept. of Phys. Peking Univ. Beijing 100871 China

Density functional method is applied for strongly correlated systems. Based on the assumption that the systems are composed of electrons in singly-occupied orbitals and those in doubly-occupied orbitals, a set of self-consistent equations are obtained by standard variation procedure. The equations consist of two parts. One part is to solve the wave functions of the electrons in singly-occupied orbitals and the other is to solve the wave functions of the electrons in doubly-occupied orbitals. The physical meanings of the terms appearing in the equations are discussed.

关键词： density-functional theory strongly correlated systems doubly-occupied orbital two-particle wave function self-consistent equations.

A general result on precise asymptotics for linear processes of positively associated sequences

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Applied Mathematics(A Journal of Chinese univ.rsities) 2008年第2期23卷 190-196页

作者： TAN Xi-li YANG Xiao-yun Dept. of Math Beihua Univ. Jilin 132013 China Institute of Math. Jilin Univ.（Qianwei Campus） Changchun 130012 China

Let {εt; t ∈ Z^＋} be a strictly stationary sequence of associated random variables with mean zeros, let 0〈Eε1^2〈∞ and σ^2=Eε1^2＋1∑j=2^∞ Eε1εj with 0〈σ^2〈∞.{aj;j∈Z^＋} is a sequence of real numbers satisfying ∑j=0^∞｜aj｜〈∞.Define a linear process Xt=∑j=0^∞ ajεt-j,t≥1,and Sn=∑t=1^n Xt,n≥*** that E｜ε1｜^2＋δ′〈 for some δ′〉0 and μ（n）=O（n^-ρ） for some ρ〉*** paper achieves a general law of precise asymptotics for {Sn}.

关键词： PA sequence linear process general law precise asymptotics.