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Regional differences and determinants of built-up area expansion in china

Science china Earth sciences 2007年第12期50卷 1835-1843页

作者： HUANG JiKun1,2,ZHU LiFen3,1 & DENG XiangZheng1,2 1 center for Chinese Agricultural Policy,Chinese Academy of sciences,beijing 100101,china 2 Institute of Geographic sciences and Natural Resources research,Chinese Academy of sciences,beijing 100101,china 3 research center of the economy of the Upper Reaches of the Yangtze River,Chongqing Technology and Business {12.,Chongqing 400067,china center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing China Institute of Geographic sciences and Natural Resources research Chinese Academy of Sciences Beijing China research center of the economy of the Upper Reaches of the Yangtze River Chongqing Technology and Business University Chongqing China

Based on remote sensing data on land use provided by the Chinese Academy of sciences and socio-economic data collected by the authors,this paper analyzes the trends and regional differences in built-up area(BUA) expansion in china from the late 1980s to 2000,and empirically estimates the major determinants of BUA expansion in different regions in 1996―*** 1989―2000,although china's overall BUA expansion accelerated,the trends differed significantly among *** expansion in the central and western regions accelerated significantly,but it slowed down considerably in the east-ern *** estimation results from our econometric analysis reveal that BUA expansion in the eastern region reached a period when economic growth had no further significant impact on per capita BUA,the land utilization in this region has become more intensive with further expansion of the *** the central and western regions,the BUA has expanded remarkably due to the relatively more flexible land development policies and the relatively cheap land ***,as the econ-omy continues to grow rapidly,policies relating to BUA expansion and cultivated land reductions may face more serious challenges in the central and western regions.

关键词： built-up area, land use, regional difference, determinants, china

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Three-dimensional decomposition method of global atmospheric circulation

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Science china Earth sciences 2008年第3期51卷 386-402页

作者： LIU HaiTao1,2,3, HU ShuJuan4, XU Ming5 & CHOU JiFan6,7 1 State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of sciences, beijing 100029, china 2 Graduate university of Chinese Academy of sciences, beijing 100049, china 3 beijing Climate center, beijing 100089, china 4 Department of Mathematics, Lanzhou university, Lanzhou 730000, china 5 Shanghai Typhoon Institute, Shanghai 200030, china 6 Department of Atmospheric sciences, Lanzhou university, Lanzhou 730000, china 7 china Meteorological Administration Training center, beijing 100089, china State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of sciences Beijing China beijing Climate center Beijing China Department of Mathematics Lanzhou University Lanzhou China Shanghai Typhoon Institute Shanghai China Department of Atmospheric sciences Lanzhou University Lanzhou China china Meteorological Administration Training center Beijing China

By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global perspective. Therefore, a m... 详细信息

关键词： three-dimensional decomposition of the global atmospheric circulation generalized Walker Hadley and Rossby stream functions existence and uniqueness vertical motion

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The new interpretation of support vector machines on statistical learning theory

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Science china Mathematics 2010年第1期53卷 151-164页

作者： ZHANG ChunHua 1 , TIAN YingJie 2 & DENG NaiYang 3,1 School of Information, Renmin university of china, beijing 100872, china 2 research center on Fictitious economy and Data Science, Chinese Academy of sciences, beijing 100080, china 3 College of Science, china Agricultural university, beijing 100083, china School of Information Renmin University of China Beijing China research center on Fictitious economy and Data Science Chinese Academy of Sciences Beijing China College of Science China Agricultural University Beijing China

This paper is concerned with the theoretical foundation of support vector machines (SVMs). The purpose is to develop further an exact relationship between SVMs and the statistical learning theory (SLT). As a representative, the standard C-support vector classification (C-SVC) is considered here. More precisely, we show that the decision function obtained by C-SVC is just one of the decision functions obtained by solving the optimization problem derived directly from the structural risk minimization principle. In addition, an interesting meaning of the parameter C in C-SVC is given by showing that C corresponds to the size of the decision function candidate set in the structural risk minimization principle.

关键词： C-support vector classification the minimization principle of the structural risk KKT conditions

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Perfect reconstruction image modulation based on BEMD and quaternionic analytic signals

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Science china(Information sciences) 2011年第12期54卷 2622-2634页

作者： QIAO LiHong 1 , NIU KaiFu 2 , WANG Ning 2 & PENG LiZhong 2 1 College of Information Science and Engineering, Henan university of Technology, zhengzhou 450001, china 2 School of Mathematical sciences, Peking university, beijing 100871, china College of Information Science and Engineering Henan University of Technology Zhengzhou China School of Mathematical sciences Peking University Beijing China

Image modulation represents image by meaningful characters such as image instantaneous amplitude and instantaneous frequency. A perfect reconstruction image modulation method is proposed. In detail, the bidimensional empirical mode decomposition (BEMD) is first improved to adaptively decompose image into monocomponents. Then by the quaternionic analytic method, suitable analytic signals is acquired. A new polar form is further proposed to modulate images, then seven characters are derived including instantaneous amplitude and instantaneous frequencies. We demonstrate the techniques on both synthetic and natural images, depict the needle program of the estimated frequencies and obtain the reconstructions that are the same with the original images. The applications in image segmentation and separation establish the validity of characterizing images of this type as sums of locally narrow band modulated components.

关键词： perfect reconstruction image modulation AM-FM representation BEMD quaternionic analytic signals

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The study on Sanmenxia annual flow forecasting in the Yellow River with mix regression model

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Science china(Technological sciences) 2004年第Z1期47卷 118-126页

作者： JIANG Xiaohui1, LIU Changming1,2, WANG Yu3 & WANG Hongrui1 1. beijing Normal university, beijing 100875, china 2. Institute of Geographic Science and Natural Resources, Chinese Academy of sciences, beijing 100101, china 3. Reconnaissance, Planning, Design and research Institute, YRCC, zhengzhou 450003, china beijing Normal university Beijing China Institute of Geographic Science and Natural Resources Chinese Academy of Sciences Beijing China Reconnaissance Planning Design and Research Institute YRCC Zhengzhou China

This paper established mix regression model for simulating annual flow, in which annual runoff is auto-regression factor, precipitation, air temperature and water consumption are regression factors; we adopted 9 hypothesis climate change schemes to forecast the change of annual flow of Sanmenxia Station. The results show : (1) When temperature is steady, the average annual runoff will increase by 8.3% if precipitation increases by 10%; when precipitation decreases by 10%, the average annual runoff will decrease by 8.2%; when precipitation is steady, the average annual runoff will decrease by 2.4% if temperature increases 1℃; if temperature decreases 1℃, runoff will increase by 1.2%. The mix regression model can well simulate annual runoff. (2) As to 9 different temperature and precipitation scenarios, scenario 9 is the most adverse to the runoff of Sanmenxia Station of Yellow River; i.e. temperature increases 1℃ and precipitation decreases by 10%. Under this condition, the simulated average annual runoff decreases by 10.8%. On the contrary, scenario 1 is the best to the enhancement of runoff; i.e. when temperature decreases 1 ℃ precipitation will increase by 10%, which will make the annual runoff of Sanmenxia increase by 10.6%.

关键词： forecast annual flow, mix regression model, Sanmenxia Station

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Soil erosion types in the loess hill and gully area of china

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Journal of environmental sciences 1995年第3期7卷 266-272页

作者： Fu Bojie(research center for eco-environmental Sceiences, Chinese Academy of Sceiences, Seeijing 100085, china)Wang Xilin(Department of Water and Soil Conservation, beijing Forestry university, beijing 100083, china)Hubert Gulinck(Institute for Land and W

ＳｏｉｌｅｒｏｓｉｏｎｔｙｐｅｓｉｎｔｈｅｌｏｅｓｓｈｉｌｌａｎｄｇｕｌｌｙａｒｅａｏｆＣｈｉｎａＦｕＢｏｊｉｅ（ＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃｏ－ＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｅｉｅｎｃｅｓ，Ｃｈｉｎｅｓｅ... 详细信息

ＳｏｉｌｅｒｏｓｉｏｎｔｙｐｅｓｉｎｔｈｅｌｏｅｓｓｈｉｌｌａｎｄｇｕｌｌｙａｒｅａｏｆＣｈｉｎａＦｕＢｏｊｉｅ（ＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃｏ－ＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｅｉｅｎｃｅｓ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｅｉｅｎｃｅ...

关键词： soil erosion type geographical information system loess hill and gully area.

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Mechanism and Defense on Malicious Code

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Wuhan university Journal of Natural sciences 2005年第1期10卷 83-88页

作者： WEN Wei-ping 1,2,3, QING Si-han 1,2,31. Institute of Software, the Chinese Academy of sciences, beijing 100080, china 2.Engineering research center for Information Security Technology, the Chinese Academy of sciences, beijing 100080, china 3.Graduate School of the Chinese Academy of sciences, beijing 100080, china Institute of Software the Chinese Academy of Sciences Beijing China Engineering research center for Information Security Technology the Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of sciences Beijing China

With the explosive growth of network applications, the threat of the malicious code against network security becomes increasingly serious. In this paper we explore the mechanism of the malicious code by giving an attack model of the malicious code, and discuss the critical techniques of implementation and prevention against the malicious code. The remaining problems and emerging trends in this area are also addressed in the paper.

关键词： malicious code attacking model mechanism defense system security network security

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Forecasting the summer rainfall in North china using the year-to-year increment approach

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Science china Earth sciences 2009年第4期52卷 532-539页

作者： FAN Ke1, LIN MeiJing1,2 & GAO YuZhong3 1 Nansen-Zhu International research center, Institute of Atmospheric Physics, Chinese Academy of sciences, beijing 100029, china 2 Graduate university of the Chinese Academy of sciences, beijing 100049, china 3 Heilongjiang Meteorological Administration, Harbin 150030, china Nansen-Zhu International research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate university of the Chinese Academy of sciences Beijing China Heilongjiang Meteorological Administration Harbin China

A new approach to forecasting the year-to-year increment of rainfall in North china in July-August (JA) is proposed. DY is defined as the difference of a variable between the current year and the preceding year (year-to-year increment). NR denotes the seasonal mean precipitation rate over North china in JA. After analyzing the atmospheric circulation anomalies associated with the DY of NR, five key predictors for the DY of NR have been identified. The prediction model for the DY of NR is established by using multi-linear regression method and the NR is obtained (the current forecasted DY of NR added to the preceding observed NR). The prediction model shows a high correlation coefficient (0.8) between the simulated and the observed DY of NR throughout period 1965-1999, with an average relative root mean square error of 19% for the percentage of precipitation rate anomaly over North china. The prediction model makes a hindcast for 2000-2007, with an average relative root mean square error of 21% for the percentage of precipitation rate anomaly over North china. The model reproduces the downward trend of the percentage of precipitation rate anomaly over North china during 1965-2006. Because the current operational prediction models of the summer precipitation have average forecast scores of 60%-70%, it has been more difficult to forecast the summer rainfall over North china. Thus this new approach for predicting the year-to-year increment of the summer precipitation (and hence the summer precipitation itself) has the potential to significantly improve operational forecasting skill for summer precipitation.

关键词： annual increment North china precipitation prediction prediction skill

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Indicator system and evaluation framework for sustainable development

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Journal of environmental sciences 1999年第4期11卷 492-497页

作者： ZHAO Jing\|zhu\+1, Johannes Baptist Opschoor\+2 (1. Department of Systems ecology, research center for eco\|environmental sciences, Chinese Academy of sciences, beijing 100085, china 2. economics Faculty, Free university, De Boelelaan 1105, 1081 HV Am 中科院生态环境研究中心北京 Free university Natherlands 荷兰

An indicator system of sustainable development was established and an evaluation framework for sustainable development was drawn in this study.

关键词： sustainable development indicator system evaluation framework

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Evolutionof Sustainable Carbon Cycling Processes in china

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Chinese Journal of Population,Resources and Environment 2004年第2期2卷 4-10页

作者： Zhuang Yahui, Zhang Hongxun,Wang Xiaoke & Fang Jinyunresearch center for eco-environmental sciences(RCEES),Chinese Academy of sciences,PO Box 2871,beijing 100085,chinaDepartment of Urban ecology,Peking university ,beijing 100871,china research center for eco-environmental sciences (RCEBS) Chinese Academy of Sciences PO Box 2871 Beijing 100085 China Department of Urban ecology Peking University Beijing 100871 China

This report summarizes the surveys on carbon inventories and initiatives on sustainable carbon cycling taken by RCEES. The first part of this report deals with the concept of sustainable carbon cycling, the historical evolution of carbon cycling processes in china, carbon pool enhancement, value addition, carbon sequestration and carbon balance. The second part covers the modeling of carbon dynamics, emission inventories of various carbon containing greenhouse gases and their potential abatement measures.

关键词： sustainable development carbon cycle carbon pool carbon sequestration

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