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Scenario simulation and forecast of land use/cover in northern china

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Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3 & HE ChunYang 3 1 college of Geographical science, Chongqing normal university, Chongqing 400047, china 2 college of Resources and Environmental science, Chongqing university, Chongqing 400044, china 3 college of Resources science & Technology, Beijing normal university, Beijing 100875, china college of Geographical science Chongqing Normal University Chongqing China college of Resources and Environmental science Chongqing University Chongqing China college of Resources science & Technology Beijing Normal University Beijing China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

Definition of Measure-theoretic Pressure Using Spanning Sets

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Acta Mathematicae Applicatae Sinica 2004年第4期 709-718页

作者： Lian Fa HE college of mathematics and information science,Hebei normal university,Shijiazhuang 050016,P.R.chinaJin Feng LV Hebei normal university of science & Technology,Qinhuangdao 066004,P.R.china Li Na ZHOU college of mathematics and information science,Hebei normal university,Shijiazhuang 050016,P.R.china

We introduce a new definition of measure-theoretic pressure for ergodic measures of con-tinuous maps on a compact metric *** definition is similar to those of topological pressureinvolving spanning *** an application,for C(α>0) diffeomorphisms of a compact manifold,we study the relationship between the measure-theoretic pressure and the periodic points.

关键词： Ergodic measure Measure-theoretic pressure Spanning set

Level Set interface treatment and its application in Euler method

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science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 227-236页

作者： WU KaiTeng1,2,HAO Li3,WANG Cheng4 & ZHANG Li1,2 1 Numerical Simulation Sichuan Higher School Key Laboratory,Neijiang normal university,Neijiang 641112,china 2 college of mathematics and information science,Neijiang normal university,Neijiang 641112,china 3 college of science,Beijing university of Civil Engineering and Architecture,Beijing 100044,china 4 State Key Laboratory of Explosion science and Technology,Beijing Institute of Technology,Beijing 100081,china Numerical Simulation Sichuan Higher School Key Laboratory Neijiang Normal University Neijiang China college of mathematics and information science Neijiang Normal University Neijiang China college of science Beijing University of Civil Engineering and Architecture Beijing China State Key Laboratory of Explosion science and Technology Beijing Institute of Technology Beijing China

Level Set interface treatment method is introduced into Euler method,which is employed for interface treatment method for multi-materials. Combined with the ghost fluid method,the moving interface is tracked. Fifth-order WENO spatial discretization and third-order TVD Runge-Kutta time discretization methods are used. Shock-wave action on bubble,implosion and velocity field Shock effect bubbles; implosion and velocity field are simulated by means of LS-MMIC3D programmed by C++. Nu-merical results show that the Level Set interface treatment method is effective and feasible for multi-material interface treatment in comparison with the WENO method.

关键词： Euler method Level Set method shock-wave action on bubble implosion numerical simulation

New fossil elaterid (Coleoptera: Polyphaga: Elateridae) from Yixian Formation of western Liaoning, china

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Progress in Natural science:Materials International 2007年第10期17卷 1244-1249页

作者： Chang Huali, Ren Dong and Shih Chungkun(college of Life science, Capital normal university, Beijing 100037, china) college of Life science Capital Normal University Beijing 100037 China

A new species of the elaterid genus Cryptocoelus Dolin and Nel, 2002 from the Late Jurassic to Early Cretaceous Yixian Formation in the western Liaoning, china is described. Diagnosis of the genus is revised, and the systematic position of the genus is briefly discussed. Because the elaterids originated in the Early to Mid-Jurassic, this new material from the Late Jurassic-Early Cretaceous will enhance our understanding of the transition between ancient elaterids and extant ones, bridge the gap of cryptic relationships between the Mesozoic cupedids and elaterids, and expand our knowledge of their evolutionary history.

关键词： Elateridae new species Yixian Formation china.

Landscape structure and land uese on county level in northeastern Yunnan Province of china——a case study of Huize County

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Journal of Environmental sciences 2000年第3期12卷 355-360页

作者： WANG Jin\|liang, NI Shao\|xiang (college of Geographical science, Nanjing normal university, Nanjing 210097, china) 南京师范大学江苏南京 2 1 0 0 97

Taking Huize County as an example, the paper analyzed the landscape structure(landscape element structure, landscape type structure, landscape spatial structure, landscape succession structure) and the relations between landscape structure and land use. It was pointed out that the agriculture should be developed in harmony with the landscape structure in the study area.

关键词： landscape structure land use agriculture Yunnan Province china

Optimal controlled teleportation via several kinds of three-qubit states

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science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1529-1556页

作者： GAO Ting1,2, YAN FengLi2,3 & LI YouCheng3 1 college of mathematics and information science, Hebei normal university, Shijiazhuang 050016, china 2 Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Str. 1, D-85748 Garching, Germany 3 college of Physics and information Engineering, Hebei normal university, Shijiazhuang 050016, china college of mathematics and information science Hebei Normal University Shijiazhuang China Max-Planck-Institut für Quantenoptik Garching Germany college of Physics and information Engineering Hebei Normal University Shijiazhuang China

The probability of successful controlled teleportation of an unknown qubit using a general three-particle state is investigated. The analytic expressions of maximal probabilities via several kinds of tripartite states... 详细信息

关键词： controlled teleportation three-qubit state maximal probability

Study on Development Strategy of DIY Farm Based on SWOT Analysis

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Asian Agricultural Research 2011年第8期3卷 8-10,14页

作者： FU Xiu-li, XIA Ming-ying college of Geography and Environmental science, northwest normal university, lanzhou 730070, china college of Geography and Environmental science Northwest Normal University

SWOT analysis method is adopted to analyze current development situations of DIY farms in china from strengths, weaknesses, opportunities and threats. On the basis of analyses, we put forward strategies for sustainable development of DIY farms, including market investigation and research, full utilization of resources, human-based management, diversified and characteristic services, as well as low price and public-oriented development, etc.

关键词： Development strategies SWOT analysis Leisure agric

实数完备性的另一个刻划及其应用——从实分析非绝对积分理论中的δ-精细分法说起

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数学的实践与认识 2004年第1期34卷 157-163页

作者：巩增泰西北师范大学数学与信息科学学院甘肃兰州730070

闭区间上δ-精细的分法是实分析非绝对积分理论中使用极为频繁的概念之一 .但是该概念的实质究竟是什么 ,本文指出 :“对任何 δ( x) >0 ,闭区间上存在 δ-精细的分法”,其实质就是实数的完备性 ;并利用该结论对数学分析中闭区间上连续... 详细信息

闭区间上δ-精细的分法是实分析非绝对积分理论中使用极为频繁的概念之一 .但是该概念的实质究竟是什么 ,本文指出 :“对任何 δ( x) >0 ,闭区间上存在 δ-精细的分法”,其实质就是实数的完备性 ;并利用该结论对数学分析中闭区间上连续函数的整体性质给出了简单证明 .

关键词：实数完备性 δ-精细分法数学分析连续函数闭区间积分学

Development and application of ergodicity model with FRCM and FLAR for hydrological process

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science china(Technological sciences) 2009年第2期52卷 379-386页

作者： WANG HongRui1, FENG QiLei2, LIN Xin3 & ZENG WenYi4 1 college of Water science, Key Laboratory for Water and Sediment sciences of the Ministry of Education, Beijing normal university, Beijing 100875, china 2 School of science, Beijing Institute of Education, Beijing 100011, china 3 School of Mathematical sciences, Beijing normal university, Beijing 100875, china 4 college of information science and Technology, Beijing normal university, Beijing 100875, china college of Water science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing China School of science Beijing Institute of Education Beijing China School of Mathematical sciences Beijing Normal University Beijing China college of information science and Technology Beijing Normal University Beijing China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2004) from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression