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

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.{2. {4. of Regional Geography of beijing Normal University 3 {2. {4. 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{2. Beijing 100048 China College of Resources Science and Technology 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, 2.4. and 2.33 times respectively from the westto the east, in which 2.0-4.0mm 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

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Soil erosion in china based on the 2.00 national remote {2. survey

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Journal of Geographical sciences 2002年第4期12卷 435-442页

作者： XU Feng1,2. GUO Suoyan2. ZHANG Zengxiang1(1. institute of remote sensing applications, CAS, beijing 100101,{2. 2. Monitoring Center of Soil and Water Conservation, Ministry of Water Resources, beijing 100053,{2.) institute of remote {2. applications CAS Beijing China Monitoring Center of Soil and Water Conservation Ministry of Water Resources Beijing China

This paper discussed the spatial distribution of soil erosion in china at the end of the 2.th century based on the second national soil erosion survey. The result indicated soil erosion is still the prime environmental problem in china. Soil erosion mainly occurs in the western regions of china, and the slight erosion type, ion the whole, exerts the greatest impact on soil erosion pattern. The distribution of water erosion shows the impact of landforms: slight water erosion mainly in mountainous and hilly areas, and half of violent water erosion on the loess landforms. Farmland, forestland and grassland are the major land use types of slight hydraulic erosion distribution, while the serious hydraulic erosion and slight wind erosion mainly occur on grassland. Thus, the conservation of the grassland is the {4. to either hydraulic and wind erosion control. The huangmian soil (a major type of cultivated soil developed from loess mother material) is the one facing the most serious threat from soil erosion in chinas soil resources. Further discussion on the soil erosion distribution still needs more research on the method and relevant data analysis.

关键词： soil erosion spatial distribution remote sensing survey china

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Positioning localities from spatial assertions based on Voronoi neighboring

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Science china(Technological sciences) 2010年第S1期53卷 143-149页

作者： GONG YongXi 1,2.3,LI GuiCai 1,LIU Yu 2.& YANG Jian 1 1 Shenzhen key Lab of Recycling Economy,Peking University Shenzhen Graduate School,Shenzhen 518055,china 2.2. of remote sensing and Geographical Information Systems,Peking University,beijing 100871,china 3College of Urban and Environmental Science,Peking University,beijing 100871,china Peking Univ Shenzhen Grad Sch Shenzhen Key Lab Recycling Econ Shenzhen 518055 Peoples R China Peking Univ Inst Remote Sensing & Geog Informat Syst Beijing 100871 Peoples R China Peking Univ Coll Urban & Environm Sci Beijing 100871 Peoples R China

With the rapid development of Internet,much spatial information contained in non-structured or semi-structured documents is available on the World Wide *** such documents,localities are always textually described using spatial relationships and named places,instead of numerical ***,extracting positional information from locality descriptions is an important *** this paper,we bridge two aspects of locality descriptions,namely generating locality descriptions and positioning localities,and provide a method to compute probability density according to the selection probability of a reference object to describe the position of the target *** operation on uncertainty field is used to deal with locality description involving multiple reference *** metrics are introduced to measure the results of positioning *** choose the mixed selection probability function based on Euclidean distance and Voronoi stolen-area to compute probability density ***,we use three cases to demonstrate the proposed methods.

关键词： geographic information science positioning locality Voronoi neighboring probability density function

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Multi-channel SAR imaging based on distributed compressive sensing

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Science china(Information sciences) 2012年第2期55卷 245-259页

作者： LIN YueGuan1,2.3,ZHANG BingChen1,2.JIANG Hai1,2.3,HONG Wen1,2.& WU YiRong1,2.1National key laboratory of Science and Technology on Microwave Imaging,{2. 100190,china 2.4. of Electronics,Chinese academy of sciences,{2. 100190,china 3Graduate University of Chinese academy of sciences,{2. 10004.,china 1. National key laboratory of Science and Technology on Microwave Imaging Beijing 100190 China2. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The rapid development of compressive sensing(CS)shows that it is possible to recover a sparse signal from very limited *** aperture radar(SAR)imaging based on CS can reconstruct the target scene with a reduced number of collected samples by solving an optimization *** multi-channel SAR imaging based on CS,each channel requires sufficient samples for separate imaging and the total number of samples could still be *** propose an imaging algorithm based on distributed compressive sensing(DCS)that reconstructs scenes jointly under multiple ***-channel SAR imaging based on DCS not only exploits the sparsity of the target scene,but also exploits the correlation among *** requires significantly fewer samples than multi-channel SAR imaging based on *** multiple channels offer different sampling rates,DCS joint processing can reconstruct target scenes with a much more flexible allocation of the number of measurements offered by each channel than that used in separate CS processing.

关键词： synthetic aperture radar multi-channel synthetic aperture radar compressive sensing distributed compressive sensing

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Development of distributed time-variant gain model for nonlinear hydrological systems

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Science china Earth sciences 2005年第6期48卷 713-723页

作者： XIA Jun1, 2. WANG Gangsheng1, TAN Ge1, YE Aizhong2.& G. H. Huang3 1. key laboratory of Water Cycle & Related Land Surface Processes, {2. of Geographic sciences and Natural Resources Research, Chinese academy of sciences, beijing 100101, china 2. state key laboratory of Water Resources & Hydropower Engineering sciences, Wuhan University, Wuhan 4.0072. china 3. Faculty of Engineering, University of Regina, 3737 Wascana Parkway, Regina, Sask., S4. 0A2. Canada Correspondence should be addressed to Xia Jun 1. key laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. state key {2. of Water Resources & Hydropower Engineering {4. Wuhan University 430072 Wuhan China 3. Faculty of Engineering University of Regina 3737 Wascana Parkway S4S 0A2 Sask Regina Canada

In this paper, a rainfall-runoff modeling system is developed based on a nonlinear Volterra functional series and a hydrological conceptual modeling approach. Two models, i.e. the time-variant gain model (TVGM) and the distributed time-variant gain model (DTVGM) that are built on the platform of Digital Elevation Model (DEM), remote sensing (RS) and Unit Hydro-logical Process were proposed. The developed DTVGM model was applied to two cases in the Heihe River Basin that is located in the arid and semiarid region of northwestern{2. and the Chaobai River basin located in the semihumid region of northern{2.. The results indicate that, in addition to the classic dynamic differential approach to describe nonlinear processes in hy-drological systems, it is possible to study such complex processes through the proposed sys-tematic approach to identify prominent hydrological relations. The DTVGM, coupling the advan-tages of both nonlinear and distributed hydrological models, can simulate variant hydrological processes under different environment conditions. Satisfactory results were obtained in fore-casting the time-space variations of hydrological processes and the relationships between land use/cover change and surface runoff variation.

关键词： hydrological process, nonlinearity, time-variant gain model, distributed hydrological model.

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Regularizing kernel-based BRDF model inversion method for ill-posed land surface parameter retrieval using smoothness constraint

Regularizing kernel-based BRDF model inversion method for il...

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中国科学院地质与地球物理研究所2.08学术年会

作者： Yanfei Wang,Changchun Yang,and Xiaowen Li 1 institute of Geology and Geophysics,Chinese academy of {2., beijing,{4.. 2.state key laboratory of remote sensing Science and Research Center for remote sensing and GIS,beijing Normal University,beijing,{4..

[1]In this paper,we consider the problem how to solve the kernel-based bidirectional reflectance distribution function(BRDF) models for the retrieval of land surface albedos. The above problem is an ill-posed inverse *** will employ a new regularization technique to alleviate the *** Tikhonov regularization has been discussed for BRDF model inversion,however,much study has to be done before applying it in practice(Wang et al,2.07).In this paper,we thoroughly investigate this method,and propose a discrepancy method for a posteriori choice of the regularization parameter and several options for choosing the regularizing *** proposed method can alleviate difficulties in numerical computation when the discrete kernel is badly conditioned and the number of observations is *** the proposed method can always find a set of suitable BRDF coefficients for poorly sampled *** proposed method is an improvement of the traditional least squares error algorithm in AMBRALS(Algorithm for MODIS(Moderate Resolution Imaging Spectroradiometer) Bidirectional Reflectance Anisotropies of the Land Surface),see Strahler et al.(1999),and is comparable to the regularized singular value decomposition method developed by Wang et al.(2.07).Hence the proposed method can be considered as a supplemental algorithm for the robust estimation of the land surface BRDF/*** performance is given in this paper for the widely used field-based 18 data sets among the 73 data sets(see Li et al.,2.01) and for the satellite data.

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Using soil surface gray level to determine surface soil water content

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Science china Earth sciences 2010年第10期53卷 1527-1532页

作者： ZHU YuanJun1,2.WANG YunQiang1,2.& SHAO MingAn1,2.1 state {4. {2. of Soil Erosion and Dryland Farming on Loess Plateau,institute of Soil and Water Conservation,Northwest A & F University,Yangling 712.00,china 2.institute of Soil and Water Conservation,Chinese academy of sciences & Ministry of Water Resources,Yangling 712.00,china 1. state key {2. of Soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water Conservation Northwest A & F University Yangling 712100 China2. Institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources Yangling 712100 China

How to determine surface soil water content(SWC) quickly and accurately is fundamental in studying eco-hydrological processes and their *** we use laboratory experiments to determine surface SWC using soil surface gray level(SGL) values.A negatively exponential relationship exists between SGL and SWC,i.e.,SGL increases with the decrease of *** can be estimated based on initial SGL value(surface gray level when SWC=0),SWC,and a surface roughness coefficient characterized by mean soil particle *** variation range of SGL was larger than that of SWC,indicating that changes in SWC were enhanced in SGL,and that SGL would thus be sensitive to changes in soil *** the 95% confidence level,SWC can be determined by using the relationship between SWC and SGL established by the *** determination of SWC has a high precision when SWC was between dry and saturated.

关键词： Loess Plateau soil water remote sensing surface roughness

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Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science china(Technological sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1 & LIU Changming1, 2.1. School of Environmental sciences, beijing Normal University, beijing 100875,{4. 2. institute of Geographic Science and Natural Resources Research, beijing 100101,{4. beijing Normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1982.1998, soil moisture of all layers of soil-profile (0—1 m) in the Yellow River basin over the 17 years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1982.to 1988 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4.00 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 17 years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

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Principle and application of three-band gradient difference vegetation index

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Science china Earth sciences 2005年第2期48卷 241-249页

作者： TANG Shihao, ZHU Qijiang, WANG Jindi, ZHOU Yuyu & ZHAO Feng Research Center for remote sensing and GIS, Department of Geography, {2. Normal University, {2. 100875,{4. National Satellite Meteorological Center,{4. Meteorological Administration, {2. 100081,{4. 1. Research Center for remote sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China 2. National Satellite Meteorological Center China Meteorological Administration 100081 Beijing China

Vegetation index is a simple, effective and experiential measurement of terrestrial vegetation activity, and plays a very important role in qualitative and quantitative remote sensing. Aiming at shortages of current vegetation indices, and starting from the analysis of vegetation spectral characteristics, we put forward a new vegetation index, the three-band gradient difference vegetation index (TGDVI), and established algorithms to inverse crown cover fraction and leaf area index (LAI) from it. Theoretical analysis and model simulation show that TGDVI has high saturation point and the ability to remove the influence of background to some degree, and the explicit functional relation with crown cover fraction and LAI can be established. Moreover, study shows that TGDVI also has the ability to partly remove the influence of thin cloud. Experiment in the Shunyi District, {2., china shows that reasonable result can be reached using the vegetation index to retrieve LAI. We also theoretically analyzed the reason why the normalized difference vegetation index (NDVI) owns the low saturation point, and show that it is determined by the definition of NDVI and the characteristic of vegetation spectra, and is unavoidable to some degree. Meanwhile, through model simulation, we also indicate that the relationship between simple ratio vegetation index (SR) and LAI closes to a piecewise linear one instead of a linear one, which is mainly caused by the influence of background and different change rates of reflectance in red and infrared bands with LAI increasing.

关键词： vegetation index, remote sensing, LAI, crown cover fraction, remote sensing inversion.

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利用弯曲度半径复函数构建综合面实体相似度模型

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测绘学报 2013年第1期42卷 145-151页

作者：付仲良逯跃锋武汉大学遥感信息工程学院武汉大学测绘遥感信息工程国家重点实验室

面实体的边界线在某点两侧割线夹角是对边界线在该点的弯曲程度和凸凹性的反映,该点与其所在几何实体边界线的中心距离又可以对面实体形状的整体进行描述,通过边界线上某点的中心距离和夹角组成复数,并对其进行快速傅里叶变换得到傅里... 详细信息

面实体的边界线在某点两侧割线夹角是对边界线在该点的弯曲程度和凸凹性的反映,该点与其所在几何实体边界线的中心距离又可以对面实体形状的整体进行描述,通过边界线上某点的中心距离和夹角组成复数,并对其进行快速傅里叶变换得到傅里叶变换系数,利用傅里叶系数构造描述形状的特征向量,该向量即为傅里叶形状描述子,作为对面实体形状相似度的度量。将面实体的空间位置、形状、大小等相似度通过加权综合获得一种综合空间相似度度量模型,利用此模型对面实体进行匹配试验结果表明,本文算法能够有效地进行面实体的匹配。

关键词：弯曲度中心距离复函数傅里叶形状描述子面实体匹配

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