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ADAPTIVE SYSTEMS THEORY: SOME BASIC CONCEPTS, METHODS AND RESULTS

Journal of Systems Science & Complexity 2003年第3期16卷 293-306页

作者： QUO Lei(institute of Systems Science, academy of Mathematics and Systems Sciences, chinese academy of Sciences, beijing 100080, china) institute of Systems Science Academy of Mathematics and Systems Sciences Chinese Academy of Sciences 北京 100080

The adaptive systems theory to be presented in this paper consists of two closely related parts: adaptive estimation (or filtering, prediction) and adaptive control of dynamical systems. Both adaptive estimation and control are nonlinear mappings of the on-line observed signals of dynamical systems, where the main features are the uncertain-ties in both the system's structure and external disturbances, and the non-stationarity and dependency of the system signals. Thus, a key difficulty in establishing a mathematical theory of adaptive systems lies in how to deal with complicated nonlinear stochastic dynamical systems which describe the adaptation processes. In this paper, we will illustrate some of the basic concepts, methods and results through some simple examples. The following fundamental questions will be discussed: How much information is needed for estimation? How to deal with uncertainty by adaptation? How to analyze an adaptive system? What are the convergence or tracking performances of adaptation? How to find the proper rate of adaptation in some sense? We will also explore the following more fundamental questions: How much uncertainty can be dealt with by adaptation ? What are the limitations of adaptation ? How does the performance of adaptation depend on the prior information ? We will partially answer these questions by finding some 'critical values' and establishing some 'Impossibility Theorems' for the capability of adaptation, for several basic classes of nonlinear dynamical control systems with either parametric or nonparametric uncertainties.

关键词： adaptive systems estimation control uncertainty stochastic systems stability

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Bifurcation stabilization of nonlinear systems by dynamic output feedback with application to rotating stall control

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Science china(information Sciences) 2012年第1期55卷 200-213页

作者： CHEN PengNian1,QIN HuaShu2,WANG Yong3&HONG YiGuang2 1Department of Mathematics,china Jiliang University,Hangzhou 310018,china 2institute of Systems Science,The chinese academy of Sciences,beijing 100080,china 3Department of Mechanics,Peking University,beijing 100871,china 1. Department of Mathematics China Jiliang University Hangzhou 310018 China2. Institute of Systems Science The Chinese Academy of Sciences Beijing 100080 China3. Department of Mechanics Peking University Beijing 100871 China

The paper deals with the problem of stabilization of stationary bifurcation solutions of nonlinear systems via dynamic output *** is emphasized that the parameter of the system is not directly *** introduce the concepts of uniform observability of the inverse of a function of state and input and N-order-input-to-state bifurcation *** on the concepts,we propose a new method for designing dynamic compensators that guarantee bifurcation stability for the closed-loop *** an example,we apply the general theory to active control of rotating stall in axial flow compressors by designing a stabilizing dynamic compensator for the three-state Moore-Greitzer model with a class of cubic compressor characteristics.

关键词： bifurcation control uniform observability dynamic output feedback rotating stall

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A Scenario on the Stepwise Evolution of the Genetic Code

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Genomics,Proteomics & Bioinformatics 2007年第Z1期 143-151页

作者： Jing-Fa Xiao and Jun Yu CAS Key Laboratory of Genome Sciences and information,beijing institute of Genomics,chinese academy of Sciences,beijing 100029,china.

It is believed that in the RNA world the operational (ribozymes) and the infor-mational (riboscripts) RNA molecules were created with only three (adenosine,uridine,and guanosine) and two (adenosine and uridine) nucleosides,respectively,so that the genetic code started uncomplicated. Ribozymes subsequently evolved to be able to cut and paste themselves and riboscripts were acceptive to rigor-ous editing (adenosine to inosine); the intensive diversification of RNA molecules shaped novel cellular machineries that are capable of polymerizing amino acids-a new type of cellular building materials for life. Initially,the genetic code,encoding seven amino acids,was created only to distinguish purine and pyrimidine; it was later expanded in a stepwise way to encode 12,15,and 20 amino acids through the relief of guanine from its roles as operational signals and through the recruitment of cytosine. Therefore,the maturation of the genetic code also coincided with (1) the departure of aminoacyl-tRNA synthetases (AARSs) from the primordial translation machinery,(2) the replacement of informational RNA by DNA,and (3) the co-evolution of AARSs and their cognate tRNAs. This model predicts gradual replacements of RNA-made molecular mechanisms,cellular processes by proteins,and informational exploitation by DNA.

关键词： genetic code codon aminoacyl-tRNA synthase GC content

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Parentage determination of an isolated Yangtze finless porpoise population Neophocaena phocaenoides asiaeorientalis in the Yangtze Tian-e-Zhou Baiji National Natural Reserve based on molecular data

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Progress in Natural Science:Materials International 2005年第2期15卷 54-61页

作者： XIA Junhong 1,2, ZHENG Jinsong 1,2, XU Limei 1,2 and WANG Ding1*(1. institute of Hydrobiology, chinese academy of Sciences, Wuhan 430072, china 2. Graduate School of the chinese academy of Sciences, beijing 100039, china) institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. Graduate School of the chinese academy of Sciences Beijing 100039 China

Reproductive behaviors are poorly known for the Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. In this study, the parentage of an isolated Yangtze finless porpoise population inhabiting the Yangtze Tian-e-Zhou Baiji National Natural Reserve is determined by analysis of microsatellite loci and mitochondrial DNA (mtDNA) control region sequences, and the porpoise's reproductive behaviors are studied. Overall 4 full parentage assignments and additional 3 single parentage assignments were determined for the population of 23 individuals. The analysis shows that their estimated reproductive cycle is shorter than that reported previously and there probably exists an overlapping between gestation and lactation period. The study also shows that the female does not show fidelity to a particular male for breeding and vice versa, the oldest males did not monopolize mating and the dominance rank could not be so strict for the porpoise society. Moreover, the porpoise's mating pattern and relatedness among candidate parents are discussed here. These results provide important information for making guidelines of management and conservation for this protected population.

关键词： Yangtze finless porpoise isolated population reproductive behavior parentage

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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2, TAO Mingxin2,3 & YE Xianren2 1. resources and Environmental School, Lanzhou University, Lanzhou 730000, china 2. Key Laboratory of Gas Geochemistry, institute of Geology and Geophysics, chinese academy of Sciences, Lanzhou 730000, china 3. College of resources Science & Technology, beijing Normal University, beijing 100875, china 1. resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of resources Science & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3He/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3He from 2.5 x 10~9 to 27 x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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Factors Influencing Timber Trade between china and Russia

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chinese forestry Science and Technology 2008年第1期7卷 20-30页

作者： LI Jianquan1 LU Wenming2 LI Zhiyong1 1.Research institute of forestry Policy and information, chinese academy of forestry, beijing 100091, P. R. china 2. Division of International Cooperation, chinese academy of forestry, beijing 100091, P. R. china

Timber trade cooperation between china and Russia is one of the most important strategic partnerships. From the supply aspect, this paper discussed the natural resource element in bilateral timber trade cooperation between china and Russia with Hecksher-Ohlin model. And from the perspective of the demand, the commercioganic effect of continuous and quick economic development in china on the bilateral trade was analyzed. At the same time, the impacts of the trade policies changes in two states as well as international market factors, such as international environmental protection, forest certification, international trade barrier, the rise of crude oil price across the world, currency appreciation and the RMB exchange rate alteration, on the bilateral timber trade cooperation between china and Russia were also clarified in this paper.

关键词： relationship timber trade influencing factor china Russia

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Eco-Environmental Vulnerability Evaluation in the Yellow River Basin,china

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Pedosphere 2008年第2期18卷 171-182页

作者： WANG Si-Yuan LIU Jing-Shi YANG Cun-Jian institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 （China） institute of Electronics Chinese Academy of Sciences Beijing 100080 （China） Centre of RS and GIS Applications Sichuan Normal University Chengdu 610066 （China）

Using remote sensing(RS)data and geographical information system(GIS),eco-environmental vulnerability and its changes were analyzed for the Yellow River Basin,*** objective of this study was to improve our understanding of eco-environmental changes so that a strategy of sustainable land use could be *** environmental numerical model was developed using spatial principal component analysis(SPCA)*** model contains twelve factors that include variables of land use,soil erosion,topography,climate,and *** this model,synthetic eco- environmental vulnerability index(SEVI)was computed for 1990 and 2000 for the Yellow River *** SEVI was classified into six levels,potential,slight,light,medium,heavy,and very heavy,following the natural breaks classification. The eco-environmental vulnerability distribution and its changes over the ten years from 1990 to 2000 were analyzed and the driving factors of eco-environmental changes were *** results show that the eco-environmental vulnerability in the study area was at medium level,and the eco-environmental quality had been gradually improved on the ***,the eco-environmental quality had become worse over the ten years in some *** the study area,population growth,vegetation degradation,and governmental policies for eco-environmental protection were found to be the major factors that caused the eco-environmental changes over the ten years.

关键词： eco-environmental vulnerability geographic information system (GIS) remote sensing (RS) spatial principal component analysis Yellow River Basin

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A New Indicator for Modern forestry Development: forest Thickness

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chinese forestry Science and Technology 2008年第4期7卷 53-60页

作者： FAN Baomin LI Zhiyong CHEN Jie Research institute of forestry Policy and information, Chinces academy of forestry, beijing 100091, P. R. china

Modern forestry focusing on ecological dimension needs some new indicators different from those designed for the traditional forestry. On the basis of the evaluation indicators for traditional forestry, such as forest coverage, total standing stock volume and forest volume per unit area, the paper came up with a new indicator called "forest thickness" (FT). FT refers to the thickness which can be got if using total stock volume of forest and trees to cover the total land in a given area, and it is charged by mm. This indicator can be used to solve the long-term problem that the forest coverage can not reflect in a comprehensive way the level of forest ecological development, and provide the easy and clear approach to measuring and comparing the levels of forest ecological development in different periods at different regions. When the indicator value is over 9 mm, the ecosystem is indicated as excellent; when in 6-9 mm, the ecosystem is indicated as good; when in 3-6 mm, the ecosystem is indicated as moderately good; when below 3 mm, the ecosystem is indicated as bad. The indicator values of FT are calculated for the world, 17 countries, and different historic periods and different regions of china, based on which the forestry ecological status in these areas are compared and evaluated.

关键词： modern forestry forest thickness forest coverage development indicator

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Main Timber Legality Verification Schemes in the World

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chinese forestry Science and Technology 2010年第3期9卷 50-55页

作者： SU Haiying1 REN Haiqing1 CHEN Yong2 1.Research institute of Wood Industry,chinese academy of forestry,beijing 100091,P.R.china 2.Research institute of forestry Policy and information,chinese academy of forestry,beijing 10091,P.R.china

Based on introduction of the timber legality verification schemes,the article provides a detailed review of existing legality verification schemes covering aspects such as definition of legality,verification *** aims to help chinese companies understand the different requirements and evidence of compliance required by legislation,public and private procurement policies.

关键词： timber legality verification

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The quantification of remote sensing

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Science china(Technological Sciences) 2005年第S2期48卷 1-11页

作者： GU Xingfa1,2,3,TIAN Guoliang1,2, LI Xiaowen1,2 & GUO Jianning4 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the institute of Remote Sensing Applications of chinese academy of Sciences and beijing Normal University, beijing 100101, china 2. The Center for National Spaceborne Demonstration, beijing 100101, china 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 4. china Center for resource Satellite Data and Application, beijing 100830, china chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China beijing Normal Univ State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Ctr Natl Spaceborne Demonstrat Beijing 100101 Peoples R China Inst Natl Rech Agron F-84914 Avignon France china Ctr resource Satellite Data & Applicat Beijing 100830 Peoples R China

The paper firstly defined the remote sensing information quantification, analyzed the necessity of developing remote sensing quantification, figured out the application guidelines requirement, and pointed out the importance of quantification research. Then taking the remote sensing application research of CBERS-02 data quantification as the example, the paper described the whole quantification system of “remotely sensed digital signal-radiation information-field parameter inversion”. Finally the paper gave the prospect for the development trend of the quantitative remote sensing.

关键词： remote sensing information quantification CBERS-02 radiometric calibration surface parame- ter reversion.

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