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The environmental signal of an early Holocene pollen record from the Shiyang River basin lake sediments, NW china

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Chinese science Bulletin 2002年第4期47卷 267-273页

作者： ZHU Yan, CHEN Fahu & Madsen Davidcollege of geography and Environment, northwest Normal {2., lanzhou 730070, china National Key Laboratory of West Environmental System, lanzhou {2., lanzhou 730000, china Utah Geological Surv college of geography and Environment Northwest Normal University Lanzhou China National Key Laboratory of West Environmental System Lanzhou University Lanzhou China Utah Geological Survey Utah USA

Pollen analyses of 85 samples from the San-jiaocheng section well along the margin of a palaeolake at the end of the Shiyang River, NW china, show that Picea and Sabina dominate the pollen assemblage. Together they reach as high as 40%-60%, with the percentage of Picea varying inversely with that of Sabina. Similar results were obtained from another section in the Shiyang River drainage. Using modern ecological habitat relationship analogues, pol-len transport characteristics, and the overall pollen assem-blage, we propose that both Picea and Sabina pollen were transported by the river from the mountains at the upper reaches of the Shiyang River, and that the assemblage is more indicative of changes in upland vegetation than of local conditions near the section. This interpretation is supported by pollen data derived from surface samples, water samples, and riverbed samples. Using a moisture indicator (the Picea to Sabina ratio) and calculated pollen concentrations, we identify a series of

关键词： NW china The environmental signal of an early Holocene pollen record from the Shiyang River basin lake sediments

Stabilization for discrete-time fuzzy systems with Takagi-Sugeno's models:reduce the complexity

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science china({2. sciences) 2010年第12期53卷 2506-2513页

作者： WANG LiKui 1 & LIU XiaoDong 2.1 School of mathematics and information {2.,Nanchang Hangkong university,Nanchang 330063,china 2.Research Center of information and Control,Dalian university of Technology,Dalian 11602.,china School of mathematics and information {2. Nanchang Hangkong University Nanchang China Research Center of information and Control Dalian University of Technology Dalian China

The problem of sate feedback control for discrete-time fuzzy systems with Takagi-Sugeno's models is investigated to reduce the computational burden.A stabilization condition is obtained by applying a new Lyapunov *** is shown that our new theorem is equivalent to an existing result in guaranteeing the stability of the fuzzy system but consumes less computational time than the *** effectiveness and the superiority of the proposed design approach are demonstrated by an example borrowed from the literature.

关键词： Takagi-Sugeno’s fuzzy model non-quadratic Lyapunov function linear matrix inequality

Maschke-type theorem and Morita context over weak Hopf algebras

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science china {2. 2006年第5期49卷 587-598页

作者： ZHANG Liangyun college of science, Nanjing Agricultural {2., Nanjing 2.0095, china Department of mathematics, Nanjing {2., Nanjing 2.0008, china college of science Nanjing Agricultural University Nanjing China Department of mathematics Nanjing University Nanjing China

This paper gives a Maschke-type theorem over semisimple weak Hopf algebras,extends the well-known Maschke-type theorem given by Cohen and Fishman and constructs a Morita context over weak Hopf algebras.

关键词： weak Hopf algebra, smash product, Maschke-type theorem, Morita context.

MMSE relay precoding schemes based on quantization error compensation for multi-relay system

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science china({2. sciences) 2010年第12期53卷 2548-2556页

作者： LI Ting 1,2.& YANG LuXi 2.1 college of Communication and information Engineering,Nanjing {2. of Posts and Telecommunications,Nanjing 2.0003,china 2.School of information science and Engineering,Southeast {2.,Nanjing 2.0096,china college of Communication and information Engineering Nanjing University of Posts and Telecommunications Nanjing China School of information science and Engineering Southeast University Nanjing China

In order to deal with the performance degradation resulting from the quantization error,this paper introduces the statistics of Grassmannian codebook's quantization error into relay precoding design for multirelay *** on the two-step MMSE optimization algorithm for relay precoding and receiver equalizing with full feedback under QoS requirements,we first propose a limited feedback two-step MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation,and then we propose a limited feedback joint MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation subject to a global power constraint at the output of *** results show that the proposed joint MMSE optimization scheme with quantization error compensation has a much lower bit-error rate than the two-step MMSE optimization scheme with quantization error compensation and the joint MMSE optimization scheme without quantization error compensation.

关键词： multi-relay precoding limited feedback minimum mean square error

Exponential attractors of the nonlinear wave equations

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Chinese science Bulletin 1998年第16期43卷 1331-1335页

作者： DAI Zhengde 1 and MA Dacai 2.1. Department of mathematics, Yunnan university, Kunming 650031,{2. 2. Department of mathematics, Shangrao Teachers college, Shangrao 334000,{2. Department of mathematics Yunnan University Kunming China Department of mathematics Shangrao Teachers College Shangrao China

The (E, E)-type exponential attractors for the nonlinear wave equation were obtained by using the decomposition of operators and finite covering *** results solves the open problem of Eden et al.

关键词： nonlinearity wave equations exponential attractors.

THE CONVERGENCE OF A NEW MODIFIED BFGS METHOD WITHOUT LINE SEARCHES FOR UNCONSTRAINED OPTIMIZATION OR COMPLEXITY SYSTEMS

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Journal of Systems science & Complexity 2010年第4期23卷 861-872页

作者： Liying LIU Zengxin WEI Xiaoping WU college of mathematics {2. Liaocheng University Liaocheng 252059 China college of mathematics and {2. science Guangxi University Nanning 530004 China School of Management Xi'an Jiaotong University Xi'an 710049 China

In this paper,a new modified BFGS method without line searches is *** traditionalBFGS method,this modified BFGS method is proposed based on the so-called fixed steplengthstrategy introduced by Sun and *** some suitable assumptions,the global convergence andthe superlinear convergence of the new algorithm are established,*** some preliminarynumerical experiments,which shows that the new Algorithm is feasible,is also reported.

关键词： BFGS method complexity systems global convergence superlinear convergence unconstrained optimization.

A new heuristic algorithm for the circular packing problem with equilibrium constraints

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science china({2. sciences) 2011年第8期54卷 1572-1584页

作者： LIU JingFa 1,2.LI Gang 3 & GENG HuanTong 1 1 School of Computer and Software,Nanjing university of information {2. & Technology,Nanjing 2.0044,china 2.Network information Center,Nanjing university of information {2. & Technology, Nanjing 2.0044,china 3 School of mathematics and Physics,Nanjing university of information {2. & Technology,Nanjing 2.0044,china School of Computer and Software Nanjing University of Information Science & Technology Nanjing China Network information Center Nanjing University of Information Science & Technology Nanjing China School of mathematics and Physics Nanjing University of Information Science & Technology Nanjing China

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 11 representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 11 instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization

The structural analysis of fuzzy measures

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science china({2. sciences) 2011年第1期54卷 38-50页

作者： ZHANG Ling1,ZHANG Bo2.& ZHANG YanPing1 1 Computer science college,Anhui {2.,Hefei 2.0039,china 2.tate Key Lab of Intelligent Technology & Systems Tsinghua National Lab for information science & Technology information science & Technology college,Computer science & Technology,Tsinghua {2.,Beijing 100084,china Computer science college Anhui University Hefei China State Key Lab of Intelligent Technology & Systems Tsinghua National Lab for information science & Technology information science & Technology {2. Computer Science & Technology Tsinghua University Beijing China

From quotient space based granular computing theory we explore the fuzzy measures of fuzzy sets. Based on the structural analysis of fuzzy sets,we present an"isotropism"*** this assumption we achieved the following insights:(1)the uniqueness of a fuzzy measure being isotropic on a finite complete semi-ordered set;(2.the necessary and suffcient condition of the isomorphism for fuzzy measure functions in fuzzy mathematics;(3)the necessary and suffcient condition that fuzzy measures have fuzzy and granular monotonicity;(4)under a certain assumption,the analytic expression for fuzzy *** results clarify the relationship between fuzzy measures and granular computing,reveal the essence of fuzzy measures,and provide a simple way of constructing fuzzy measures.

关键词： quotient space fuzzy set fuzzy measure rough set structural analysis

Further study of sources of the imported cobalt-blue pigment used on Jingdezhen porcelain from late 13 to early 15 centuries

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science china(Technological sciences) 2008年第3期51卷 249-259页

作者： DU Feng1 & SU BaoRu2.1 Institute of Chemistry & Molecular Engineering, Qingdao university of science & Technology, Qingdao 2.6000,{2. 2.college of information science Technology, Qingdao university of science & Technology, Qingdao 2.6000,{2. Institute of Chemistry & Molecular Engineering Qingdao University of Science & Technology Qingdao China college of information {2. Technology Qingdao University of Science & Technology Qingdao China

Based on the conclusion of modern scientific analysis: the cobalt-blue pigment applied on Jingdezhen official porcelain during Yuan Dynasty and prior to Xuande reign of Ming Dynasty (12.1―142.) contains high iron and low manganese con- tents, and the cobalt during Xuande and after Xuande periods (after 142.) of Ming Dynasty contains high manganese and low iron contents, in combination with the traditional archaeological method, the related historical textual records were in- vestigated and analyzed, the imported cobalt employed on Jingdezhen official porcelain was studied comprehensively, systematically and logically. In fact, 'Su Ma Li Qing' (Samarra-blue) and 'Su Bo Ni Qing' (Sumatra-blue) are definitely different cobalt ores originated in different places, because of their very similar translitera- tions in Chinese, the confusion has appeared in ancient books for more than 400 years, which considered 'Su Ma Li Qing' and 'Su Bo Ni Qing' as the same co- balt-blue pigment. In this article the mistake was corrected, the possible producing places and the approximate eras of the two pigments imported to china and used at Jingdezhen were also suggested.

关键词： imported cobalt-blue pigments employed on official blue-and-white porcelain Yuan Dynasty early Ming Dy- nasty Mn/Fe content ratio Su Ma Li Qing (Samarra-blue) Su Bo Ni Qing (Sumatra-blue) scientific archae- ological research transliteration