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

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{4. {3., Chongqing 4.004., China 2 college of resources and Environmental science, Chongqing {3., Chongqing 4.004., China 3.college of resources science & {14., Beijing{4. {3., Beijing 100875, China college of Geographical science Chongqing Normal University Chongqing 400047 China college of resources and Environmental{2. Chongqing University Chongqing 400044 China college of resources{2. & {3. Beijing Normal University Beijing 100875 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 3. 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

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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 {4. university, Beijing {2., China 2. State Key Laboratory of Remote Sensing {3., Beijing {2., China 3. Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, Beijing {2., China 4. Department of Information Management, college of Information and Electronic Engineering, China Agricultural university, Beijing 100083. China 1. Research Center for Remote Sensing and GIS School of Geography Beijing Normal University 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 University Beijing 100083 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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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 {2. of Water science, Key Laboratory for Water and Sediment sciences of the Ministry of Education, Beijing {3. university, Beijing 100875, China 2.School of science, Beijing Institute of Education, Beijing 100011, China 3.School of Mathematical sciences, Beijing {3. university, Beijing 100875, China 4.{2. of Information science and {13., Beijing {3. university, Beijing 100875, China 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 {2. and {2. Beijing Normal University Beijing 100875 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―2.04. 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

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Exotic structure of the third excited state in^(2.)Na

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Chinese science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2.3. LIANG Yujie1,2.3. DENG Fuguo1,2.3. LIU Zuhua1,4.& ZHOU Hongyu1,2.3.1. Key Laboratory of Beam {4. and Material Modification of Minister of Education, Beijing normal {2., Beijing {3., China 2. Institute of Low Energy Nuclear Physics, and Department of Material science and Engineering, Beijing normal {2., Beijing {3., China 3. Beijing Radiation Center, Beijing {3., China 4. China Institute of Atomic Energy, Beijing 102.3}3. China Key Laboratory of Beam technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China Institute of Low Energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing 100875 China Beijing Radiation Center Beijing 100875 China China Institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficie... 详细信息

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (2.1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.7{2. and 2.1/2.5.2. fm respectively. The P value and the contribution of the asymptotic part to the 2.1/2.are compared with those of several other low energy states in 2.Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 2.Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 2.Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

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A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW China

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science China Earth sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12. TANG Lingyu1, FENG Zhaodong3.4. ZHANG Hucai2. WANG Weiguo3.& AN Chenbang3.1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, Nanjing 2.0008, China 2. Nanjng Institute of Geography and Limnology, Chinese Academy of sciences, Nanjing 2.0008, China 3. Environment and {2. {3., Lanzhou university, Lanzhou 73.000, China 4. Beijing {12. university, Beijing 100875, China 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and resources {2. Lanzhou University Lanzhou 730000 China 4. Beijing normal {2. Beijing 100875 China

With the support of 18 AMS-14. data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 4..2.to 11 ka B.P. in the Jingning area. Over the period of 4.―2. ka B.P. (MIS3., coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 2.3}ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3. further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,China

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science China Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3.& YE Xianren2.1. resources and Environmental School, Lanzhou {2., Lanzhou 73.000, China 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of{4.s, Lanzhou 73.000, China {3., Beijing normal {2., Beijing 100875, China 1. resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. college of resources science & technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, China, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternChina; ratios of ~3.e/~4.e in almost all samples range from 0.82.Ra to 2.74.Ra, whereas^(4.)Ar/^(3.)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3.e from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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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.{2. Yang Mingchuan 3.{2.& Zhou Junju 11 college of Geography & Remote Sensing 2.Key Laboratory of Regional Geography of Beijing {{2. {2. 3.Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education of China {2.college of resources {12. & technology, Beijing {{2. {2., 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{2. and {3. 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 {2. 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 2.3. 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 {2.. 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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Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2. WU Li-xin1, 2. LI Hui-ying3.1. college of {2. and Civil Engineering, Northeastern {2., Shenyang 110004. China 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, Beijing {3. {2., Beijing 100875, China 3. college of Computer science and technology, Jilin {2., Changchun 13.012. China [a] college of resources and Civil Engineering Northeastern University Shenyang 110004 China [b] Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China [c] college of Computer science and{2. Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3. scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3. mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm

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Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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science China(Physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3. WANG Yong2. DU Xiaolong1, MEI Zengxia1, KONG Xianghe3. JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2. {2.1. State Key Laboratory for Surface Physics, Institute of Physics, Chinese Academy of sciences, Beijing 100080, China 2. Laboratory of Electron Microscopy, Institute of Physics, Chinese Academy of sciences, Beijing 100080, China 3. {2. of Physics and Engineering, Qufu {3. university, Qufu 2.3.65, China {2. Beijing university of {12., Beijing 10002., China 1. State Key Laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. college of Physics and Engineering Qufu Normal University 273165 Qufu China 3. Laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences 100080 Beijing China 4. Beijing university of {2. 100022 Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 3. rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.

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Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

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Wuhan university Journal of Natural sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2.3., ZHOU Wancun 1 ,ZHOU Jieming 4., ZHU Mingcang 3.5 1. Institute of Mountain Hazards and Environment, Chinese Academy of sciences , Chengdu 61004., Sichuan, China 2. Graduate university of Chinese Academy of sciences, Beijing 10004., China 3. Sichuan Institute of Land Resource Management, Chengdu 61004., Sichuan , China 4. Department of {3. and Environment science, Sichuan normal university , Chengdu 610061, Sichuan, China 5. college of Information Engineering, Chengdu university of technology, Chengdu 610059, Sichuan, China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate university of Chinese Academy of sciences Beijing China Sichuan Institute of Land Resource Management Chengdu Sichuan China Department of resources and Environment science Sichuan Normal University Chengdu Sichuan China college of Information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2.02. the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

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