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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 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 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(1950-2000), the increasing extent of 5- was 1.71,2.96, 2.41 and 2.3. times respectively from the westto the east, in which 200-400mm 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

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Optimal reactions for the synthesis of superheavy nucleus ^(270)Hs

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Science China(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3.& BAO Jingdong1,2 1. key Laboratory of Beam Technology and Material Modification of Ministry of Education, beijing normal {3., beijing 100875, China 2. Physics Department, beijing normal {3., beijing 100875, China 3. China Institute of Atomic Energy, beijing 102413. China key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China China Institute of Atomic Energy Beijing China Physics Department Beijing Normal University Beijing China

The superheavy nucleus 270Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 248Cm(26Mg,4n)270Hs, 244Pu(3.Si,4n)270Hs, 23.U(3.S,4n)270Hs and 226Ra(48Ca,4n)270Hs using a two-parameter Smoluchowski equation. It is found from our results that 226Ra(48Ca,4n)270Hs and 23.U(3.S,4n)270Hs are two optimal reactions for the synthesis of the superheavy nucleus 270Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

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Retrieving crop leaf area index by assimilation of MODIS data into a crop growth model

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Science China Earth Sciences 2010年第5期53卷 721-730页

作者： WANG DongWei1,2,3. WANG JinDi1,2 & LIANG ShunLin4 1 State key Laboratory of Remote Sensing Science, Jointly Sponsored by beijing normal {3. and Institute of Remote Sensing Applications, CAS, beijing 100875, China 2 School of geography, beijing key Laboratory of Environmental Remote Sensing and Digital City, beijing normal {3., beijing 100875, China 3.Haihe River Water Conservancy Commission, Tianjin 3.0170, China 4 Department of geography, {3. of Maryland, College Park, MD 20742, USA State key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications CAS Beijing China School of geography Beijing Key Laboratory of Environmental Remote Sensing and Digital City Beijing Normal University Beijing China Haihe River Water Conservancy Commission Tianjin China Department of geography University of Maryland College Park USA

Leaf area index (LAI) is an important parameter in monitoring crop growth. One of the methods for retrieving LAI from remotely sensed observations is through inversion of canopy reflectance models. Many model inversion methods fail to account for variable LAI values at different crop growth stages. In this research, we use the crop growth model to describe the LAI changes with crop growth, and consider a priori LAI values at different crop growth stages as constraint information. The key approach of this research is to assimilate multiple canopy reflectance values observed at different growth stages and a priori LAI values into a coupled crop growth and radiative transfer model sequentially using a variational data assimilation algorithm. Adjoint method is used to minimize the cost function. Any other information source can be easily incorporated into the inversion cost function. The validation results show that the time series of MODIS canopy reflectance can greatly reduce the uncertainty of the inverted LAI values. Compared with MODIS LAI product at Changping and Shunyi Counties of beijing, this method has significantly improved the estimated LAI temporal profile.

关键词： inversion leaf area index crop growth model time series MODIS

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Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science China Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2,3. WANG Pengxin4, YANG Hua1,2,3. LIU Shaomin1,2,3.& WANG Jindi1,2,3.1. Research Center for Remote Sensing and GIS, School of geography, beijing normal {3., beijing 100875, China 2. State key Laboratory of Remote Sensing Science, beijing 100875, China 3. beijing key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875, China 4. Department of Information Management, College of Information and Electronic Engineering, China Agricultural {3., beijing 100083. China Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing China State key Laboratory of Remote Sensing Science Beijing China beijing key Laboratory for Remote Sensing of Environment and Digital Cities Beijing China Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

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Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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Science China(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2, WANG Chuan1, DENG Zhiwei3. LU Zhiheng4, & LONG Guilu1,5 1. key Laboratory For Quantum Information and Measurements of MOE, Department of Physics, Tsinghua university, beijing 100084,China 2. Department of Materials Science and Engineering, beijing normal university, beijing 100875, China 3. Testing and Analytical Center, beijing normal university, beijing 100875,China 4. Department of Physics, beijing normal university, beijing 100875, China 5. key Laboratory For atomic and Molecular Nanosciences, Tsinghua university, beijing 100084,China key Laboratory For Quantum Information and Measurements Department of Physics Tsinghua University Beijing 100084 China Department of Materials Science and Engineering Beijing Normal University Beijing 100875 China Testing and Analytical Center Beijing Normal University Beijing 100875 China Department of Physics Beijing Normal University Beijing 100875 China key Laboratory for Atomic and Molecular Nanosciences Tsinghua University Beijing 100084 China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

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Quick image-processing method of UAV without control points data in earthquake disaster area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 523-528页

作者： LI Chang-chun1, ZHANG Guang-sheng1, LEI Tian-jie2, 3. GONG A-du2, 3.1. School of Surveying & Land Information Engineering, Henan Polytechnic university, Jiaozuo 454000, China 2. key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, beijing {3. university, beijing 100875, China 3. Ministry of Civil Affairs/Ministry of Education of China Academy of Disaster Reduction and Emergency Management, beijing {3. university, beijing 100875, China School of Surveying & Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China key Laboratory of Environmental Change and Natural Disaster Ministry of Education Beijing Normal University Beijing 100875 China Ministry of Civil Affairs/Ministry of Education of China Academy of Disaster Reduction and Emergency Management Beijing Normal University Beijing 100875 China

The methods of unmanned aerial vehicles images splicing rapidly and rectifying without control points data, only using auxiliary data recorded by unmanned aerial vehicle (UAV) system, were researched. Two algorithms were proposed, including UAV images auto- splicing rapidly after image blocking and UAV images rectifying based on pseudo center points of auxiliary data. When SIFT algorithm for UAV images splicing is applied, the accuracy is very high, but the efficiency is very low. The splicing efficiency is improved greatly based on SIFT algorithm after image blocking. The results show that rectifying accuracy is very high and has no visual dislocation when pseudo center points of auxiliary data is applied.

关键词： unmanned aerial vehicles SIFT algorithm blocking quickly splicing rectification

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Node ordinal encoded genetic algorithm for the optimal allocation of water resources

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Progress in Natural Science:Materials International 2005年第5期15卷 448-452页

作者： YANG Xiaohua1*, YANG Zhifeng 1,2, SHEN Zhenyao1 and LI Jianqiang3.1. State key Laboratory of Water Environment Simulation, School of Environment, beijing normal {3., beijing 100875, China 2. key Laboratory for Water and Sediment Sciences Ministry of Education, School of Environment, beijing normal {3., beijing 100875, China 3. Water Resources and Hydropower Planning and Design General Institute, MWR, beijing 100011, China) State key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China key Laboratory for Water and Sediment Sciences Ministry of Education School of Environment Beijing Normal University Beijing 100875 China Water Resources and Hydropower Planning and Design General Institute MWR Beijing 100011 China

A new method, node ordinal encoded genetic algorithm (NOEGA), is proposed for solving water resources optimal allocation problems, in which the capacity of water resources is split into a number of smaller parts so that successive operations can be overlapped. Our objective is to maximize the whole benefit function. To overcome the “dimensionality and algorithm complexity curse” while searching for solutions and looking for an optimal solution, the operations of one-point crossover operator, gene exchange operator, gene random operator, gene shift operator and node ordinal strings are established. It is proved to be an effective optimal method in searching for global solutions. The NOEGA does not need a diversity of initial population, and it does not have the problem of immature convergence. The results of two cases show that using NOEGA to solve the optimal allocation model is very efficient and robust. In addition, the algorithm complexity of NOEGA is discussed.

关键词： water resources optimal allocation node ordinal code genetic algorithm.

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Test of magnetic susceptibility and grain-size age models of loess

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Progress in Natural Science:Materials International 2007年第11期17卷 1312-1317页

作者： Chen Yimeng1,2,3. Feng Zhaodong4 and Gong Huili1,2(1. MOE and key Laboratory of Resources Environment and GIS of beijing, beijing 10003., China 2. key Laboratory of 3. information Acquisition and Application, The Capital normal university, beijing 10003., China 3. Department of Economics & Management of Huizhou university, Huizhou 516007, China 4. key Laboratory of Western China’s Environmental Systems, Ministry of Education, Lanzhou university, Lanzhou 73.000, China) MOE and key Laboratory of Resources Environment and GIS of beijing Beijing 100037 China

Ages of the stratigraphic boundary MIS1/2 and MIS3.4 of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2 and MIS3.4 are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2 is 11.5 kaB.P. and MIS3.4 is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2: 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3. 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14C age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model.

关键词： loess nodal control age magnetic susceptibility age model grain-size age model test

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Multiple time scale evaluation of the energy balance during the maize growing season,and a new reason for energy imbalance

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Science China Earth Sciences 2009年第1期52卷 108-117页

作者： GUO JianXia1,2,BIAN LinGen3.& DAI YongJiu2 1 Meteorological Observation Center of China Meteorological Administration,beijing 100081,China 2 State key Laboratory of Remote Sensing Science,School of geography and Remote Sensing Science,beijing normal university,beijing 100875,China 3.Chinese Academy of Meteorological Sciences,beijing 100081,China Meteorological Observation Center of China Meteorological Administration Beijing China State key Laboratory of Remote Sensing Science School of Geography and Remote Sensing Science Beijing Normal University Beijing China Chinese Academy of Meteorological Sciences Beijing China

Energy imbalance is a common problem associated with the measurement of surface energy using the eddy covariance *** the evaluation of the energy balance,people usually pay more attention to the statistical result that the effective energy(the sum of sensible and latent heat) is systematically lower than the available energy(the difference of net radiation and ground heat flux).However,little attention has been paid to the existence of the reversed situation when the effective energy is larger than the available energy or their contribution to the overall energy closure *** this paper,based on the analysis of the energy balance on multiple time scales across the maize growth season,we conclude that the non-synchronization of energy components is the main reason for the existence of the reversed *** shifting the phase of the effective energy components half an hour ahead,the rates of energy closure over all time scales are improved and dramatically reduce the number of the half-hourly samples when the energy ratio exceeds 1 or is below *** to the characteristics of the energy distribution and transformation over multiple time scales,latent heat is always the main type of energy cost,and the residual of the energy balance increases with the growth of the maize plant surpassing the sensible heat for seventy *** is suggested that the heat storage and photosynthetic energy play an important role in the energy balance during the growing period of maize.

关键词： maize energy balance multiple time scale energy hysteresis

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Estimating surface evapotranspiration using combined MODIS and CBERS-02 data

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Science China(Technological Sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2, LIU Qinhuo1, TANG Yong1,3. TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2, ZHENG Hongsheng4 & CHEN Jiayi4 1. State key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, beijing 100101, China 2. Research Center for Remote Sensing and GIS, Department of geography, beijing normal university, beijing 100875, China 3. Graduate university of Chinese Academy of Sciences, beijing 10003., China 4. Department of Atmospheric Physics, Peking university, beijing 100871, China State key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02 data were used to produce land use class of Baiyangdian area, Hebei Province, China in the autumn of 2004. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

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