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Entropy number and non-linear approximations on multivariate Besov space by manifolds of finite pseudo-dimension

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Progress in Natural science:Materials International 2006年第3期16卷 260-265页

作者： LONG Jingfan and FANG Gensun (School of Mathematical sciences, beijing normal university, {2. 100875, China Department of Computer science, information technology Institute, {2. 100101, China) School of Mathematical sciences Beijing Normal University Beijing 100875 China Department of Computer science Information Technology Institute Beijing 100101 China

We determine the asymptotic order of entropy number and optimal non -linear approximations of anisotropic periodic Besov class of Bpθr(Td') (1≤p≤∞,1≤0≤∞) by manifolds of finite pseudo-dimension in the metric Lq... 详细信息

关键词： Pseudo-dimension anisotropic Besov class of functions entropy number nonlinear width.

Automatic generalization of metro maps based on dynamic segmentation

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science China(Technological sciences) 2010年第S1期53卷 158-165页

作者： DONG WeiHua 1,TIAN Yuan 2.& ZHANG Yi 2.1 Institute of Geography and Remote Sensing,beijing normal {2.,beijing 100875,China 2.Institute of Remote Sensing and Geographic information System,Peking {2.,beijing 100871,China Institute of Geography and Remote Sensing Beijing Normal University Beijing China Institute of Remote Sensing and Geographic information System Peking University Beijing China

A metro map is usually optimized for the readability of connections and transportation networks *** order to assure good readability and meet aesthetic considerations,a set of principles for good metro map layout are *** to these principles,a new methodology based on dynamic segmentation is presented to produce the metro maps ***,routes are constructed according to the line attribute similarity and geometry *** a set of cartographic generalization methods about the shape,angle,length,and topology are presented for these *** method is validated by beijing metro plan *** the experiment results,it can be concluded that this new method is more effective than the static segmentation method to produce metro maps with better readability for route plans.

关键词： metro maps generalization dynamic segmentation visualization

Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model

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science China Earth sciences 2005年第11期48卷 1979-1989页

作者： HE Chunyang, SHI Peijun, CHEN Jin, Li Xiaobing, PAN Yaozhong, LI Jing, LI Yuechen & LI Jinggang Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of China, beijing normal university college of Resources {2. & technology, beijing normal university, beijing 100875, China Key Laboratory of Environmental Change and Natural Disaster Ministry of Education of China Beijing Normal University China college of Resources science & {2. Beijing Normal University Beijing China

Modeling land use scenario changes and its potential impacts on the structure and function of the ecosystem in the typical regions are helpful to understanding the interactive mechanism between land use system and ecological system. A Land Use Scenario Dynamics (LUSD) model by the integration of System Dynamics (SD) model and Cellular Automata (CA) model is developed with land use scenario changes in northern China in the next 2. years simulated in this paper. The basic idea of LUSD model is to simulate the land use scenario de-mands by using SD model at first, then allocate the land use scenario patterns at the local scale with the considerations of land use suitability, inheritance ability and neighborhood effect by using CA model to satisfy the balance between land use scenario demands and supply. The application of LUSD model in northern China suggests that the model has the ability to reflect the complex behavior of land use system at different scales to some extent and is a useful tool for assessing the potential impacts of land use system on ecological system. In addition, the simulated results also indicate that obvious land use changes will take place in the farming-pastoral zone of northern China in the next 2. years with cultivated land and urban land being the most active land use types.

关键词： system dynamics, cellular automata, scenario, land use, model

Modulation on the collective response behavior by the system size in two-dimensional coupled cell systems

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science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 304-312页

作者： ZHANG Jiqian1, SHEN Chuansheng1,2.& CUI Zhifeng1 1. college of Physics and Electronic information, Anhui {2. university, Wuhu 2.1000, China 2. Department of Educational technology, Anqing Teachers college, Anqing 2.6011, China college of Physics and Electronic information Anhui Normal University Wuhu China Department of Educational technology Anqing Teachers College Anqing China

By the intracellular calcium ionic minimal model proposed by Berridge, we investigated the collective response of two-dimensional (N×N) coupled cell systems to the external stimulation using numerical simulation methods. With a coupled intensity fixed and an appropriate coupled cell number chosen, the kinetic system size resonance was discovered. At the same time, it was found that the system size responding to the external stimulation for different coupled intensities transferred too, especially when the coupled intensity increased, the range of the corresponding system size extended. These phe- nomena illustrate that the coupled cell number and the coupled intensity can play con- structive roles in noisy coupled systems, by which the biology system would probably improve its capability to respond to the external stimulation.

关键词： cell coupling,collective response,system size resonance

Weighted weak type estimates for commutators of the Marcinkiewicz integrals

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science China Mathematics 2004年第1期47卷 83-95页

作者： DING Yong, LU Shanzhen & ZHANG PuDepartment of Mathematics, beijing normal university, beijing {2., China Department of information and Computing science, Zhejiang Institute of science and technology, Hangzhou 310033, China Department of Mathematics Beijing Normal University Beijing China Department of information and Computing science Zhejiang Institute of Science and Technology Hangzhou China

In this paper the authors give the weighted weak LlogL type estimates for a class of the higher order commutator generated by the Marcinkiewicz integral and a BMO function. In addition, the weak type norm inequalities... 详细信息

关键词： Marcinkiewicz integral, commutator, Ap weight, weak type estimate.

Study on Water Consumption Coefficient of People's Living and Its Regional Disparity in the North of China

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Chinese Journal of Population,Resources and Environment 2005年第2期3卷 20-26页

作者： Wang Jing’ai 1-3, Mao Rui 3,4, Yang Mingchuan 3,4 & Zhou Junju 11 college of Geography & Remote Sensing 2.Key Laboratory of Regional Geography of beijing normal university 3 Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education of China 4 college of Resources science & technology, beijing normal university, beijing 100875, China college of Geography and Remote Sensing Beijing 100048 China Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education of China Beijing 100048 China college of Resources science and {2. Beijing Normal University Beijing 100875 China

By employing the information-reshufflingmethod that integrates census data, precipitation dataand inquiry data of water consumption, this paperdiscusses 5 (water consumption coefficient of people’sliving) in allusion to different precipitation zones anddifferent periods of time. The study shows that 5-(water consumption coefficient of urban people’sliving), 5. (water consumption coefficient of ruralpeople’s living) and increase with time passing, andthe increasing extent of 5 is 1.84, 2.62. 2.84 and 2.68times respectively from the west to the east, whichresults from the total quantity of water resources andthe speed of urbanization. 5- and 5. of eachprecipitation zone increased with 5- increasing morequickly than 5., and the difference between the twoalso increased when time passed. In the past fifty years(1950-2.00), the increasing extent of 5- was 1.71,2.96, 2.41 and 2.33 times respectively from the westto the east, in which 2.0-400mm precipitation zoneincreased more than others. Meanwhile the increasingextent of 5. is 1.55, 1.60, 1.53 and 1.64 timesrespectively from the west to the east with eachprecipitation zone increasing similarly. The change of5-is due to the speed of urbanization and the stabilityof water resources. This study provides basis forcalculating the water demand of people’s living andrevealing the impact of water demand of people’s livingon ecological drought in different zones.

关键词： The north of China precipitation zone water consumption coefficient of people’s living

Dense coding scheme using superpositions of Bell-states and its NMR implementation

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science China(Physics,Mechanics & Astronomy) 2005年第1期48卷 57-67页

作者： ZHANG Jingfu, XIE Jingyi, DENG Zhiwei & LU Zhiheng Key Laboratory for Quantum information and Measurements, Department of Physics, Tsinghua university, {2. 100084, China Center for Quantum information, Tsinghua university, {2. 100084, China Department of Materials science and Engineering, beijing normal university, {2. 100875, China Testing and Analytical Center, beijing normal university, {2. 100875, China Department of Physics, beijing normal university, {2. 100875, China Key Laboratory for Quantum information and Measurements Department of Physics Tsinghua University Beijing 100084 China Center for Quantum information Tsinghua University Beijing 100084 China Department of Materials science and Engineering Beijing 100875 China Testing and Analytical Center Beijing Normal University Beijing 100875 China Department of Physics Beijing Normal University Beijing 100875 China

Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR)quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system.

关键词： dense coding, superpositions of Bell-states, generalized Grover's algorithm, nuclear magnetic res-onance, quantum computer.

Sedimentary facies of the Silurian tide-dominated paleo-estuary of the Tazhong area in the Tarim Basin

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Petroleum science 2008年第2期5卷 95-104页

作者： Zhang Jinliang Zhang Zhongjie college of Resource science and {2. Beijing Normal University Beijing 100875 China School of Marine Geo-science Ocean University of China Qingdao Shandong 266100 China

As the relative sea-level rose, a paleo-estuary was formed by the marine inundation of the braided river incised valley during the period of the lower sub-member of the upper member of the Kalpingtage. formation of the Silurian in the Tarim Basin, west China. Sandstone-mudstone rhythmite, tidal structures and bimodal cross-bedding are common in these deposits, indicating that tides played a significant role in generating the sedimentary structures and the estuary type was tide-dominated. Five depositional facies were grouped： tidal river, sandy and muddy subtidal flat, tidal flat, tidal bar, tidal channel on the basis of lithology, electric properties, rhythmicity, sedimentary structure, fossil and the contact relationship. The sediment distribution showing first fining seaward and subsequent coarsening seaward from head to mouth, implies the two sediment sources in the paleo-estuary. The paleo-estuary of the Tarim Basin is very different from other representative estuaries. The most important distinction is that there are two adjacent estuaries joined by tidal flat onshore and by sandy and muddy subtidal flat in the sea at the same time, while the others only architecture model for the tide-dominated estuary. have one, So the Tazhong paleo-estuary shows a good

关键词： Tarim basin Silurian tide-dominated estuary tidal river tidal bar

Non-invasive scanning ion-selective electrode technique and its applications to the research of higher plants

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Progress in Natural science:Materials International 2007年第6期17卷 625-629页

作者： Sun Tong1, Xu Yue2. Li Peng1, Yu Shangguan2.and Yin Liping1(1. college of Life science, Capital {2. university, beijing 100037, China 2. Younger USA science & technology Corporation, 7 Dayton Lane, Amherst MA 01002. USA) college of Life science Capital Normal University Beijing 100037 China Younger USA science and technology Corporation 7 Dayton Lane Amherst MA 01002 United States

The process of various ions and molecules getting into and out of cells is critical for plant survival. The non-invasive scanning ion-selective electrode technique (SIET) is a non-invasive method to obtain the information of ions/molecules across membranes in plant. This technique can measure the absolute concentration of ions and molecules, and also their fluxes and directions of movement. The samples to be analyzed can be a single cell, a piece of tissue, a whole organ and even an intact seedling. This article reviews the recent progress made in plant physiology by using this technique and discusses its potentials in future studies on plant physiology.

关键词： non-invasive electrophysiology technique ion-selective electrode ion transport across membrane SIET.