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natural convection gas pendulum and its application in accelerometer and tilt sensor

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Progress in natural science:Materials International 2005年第9期15卷 857-860页

作者： ZHANG Fuxue(research Center of Sensor Technology, beijing Information Technology {2., beijing 100101, china) research Center of Sensor Technology Beijing Information Technology Institute Beijing 100101 China

It is discovered that the natural convection gas has the pendulum characteristic, which leads to the introduction of the new concept of gas pendulum. In this paper, the buoyancy lift of natural convection gas is analyzed in a hermetic chamber, and the relationship between the buoyancy lift and the change of temperature is formulated. The experimental results show that the gas pendulum, similar to the solid pendulum and liquid pendulum, can be utilized to sense the acceleration and the tilt angle.

关键词： natural convection accelerometer tilt sensor.

Land use change in Bohai Rim: a spatial-temporal analysis

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Journal of geographical sciences 2001年第3期11卷 305-312页

作者： ZHU Hui-yi, LI Xiu-bin, HE Shu-jin, ZHANG Ming (institute of geographic {2.s and natural resources research, CAS, beijing 100101, china) institute of geographic {2.s and natural resources research

Based on RS and GIS methods, land use information for 1985 and 1995 was acquired from TM images and analyzed. Then on both spatial and temporal aspects, this paper analyzes land use change in three provinces of Hebei, Shandong and Liaoning and two municipalities of beijing and Tianjin in the Bohai Rim covering the period of 1985 to 1995. The extent, rate, areal difference and trend of various types of land use changes in the region, as well as spatial changes of major types of land use, their distribution characteristics and regional orientation are revealed. The regional characteristics of land use are elaborated, so as to provide effective policy support for sustainable land use in the area around the Bohai Bay.

关键词： Bohai Rim land use change spatio-temporal analysis

Differential Hydrological Grey Model (DHGM) with self-memory function and its application to flood forecasting

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science china(Technological sciences) 2009年第4期52卷 1039-1049页

作者： CHEN XiangDong1, XIA Jun1,2.& XU Qian3 1 Key Laboratory of Water Cycle and Related Land Surface Processes, institute of geographic {2.s and natural resources research, Chinese Academy of {2.s, beijing 100101, china 2.State Key Laboratory of Water resources and Hydropower Engineering {2., Wuhan University, Wuhan 430072. china 3 School of Hydrology and Water resources, Hohai University, Nanjing 2.0098, china 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 2. State Key Laboratory of Water resources and Hydropower Engineering science Wuhan University Wuhan 430072 China 3. School of Hydrology and Water resources Hohai University Nanjing 210098 China

This paper addresses a problem of flood forecasting with the self-memory function. Considering flood forecasting’s uncertainty and updating demand, a hybrid hydrological model, namely Differential Hy- drological Grey Model with self-memory function (DHGM-SM), is developed. The model has two fold features. One is to establish a self-memorization equation linked with DHGM, that could extract useful information from past data series and realize updating of hydrological dynamic process. The other is that this model has higher efficiency relative to original hydrological model without self-memory func- tion. This approach was applied to river flow forecasting of two representative basins in Tunxi of South china and Daqinggou of North china. It is shown that this hybrid method has satisfactory forecasting accuracy by examination of both calibration and validation.

关键词： differential grey model the self-memorization principle real-time forecasting faded-memory recursive least square method

In situ reproductive organs of Early Cretaceous ferns from Northeast china

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Chinese science Bulletin 1997年第23期42卷 1977-1980,2026页

作者： DENG Shenghui and CHEN Fen1. research institute of Petroleum and Development, {2. 100083 2. china University of Geosciences, {2. 100083, china research institute of Petroleum and Development Beijing china University of Geosciences Beijing China

FILICOPSIDA is a predominant group of the Early Cretaceous floras of Northeast china, whichapproximates 100 species and accounts for more than one third of the floras. The majority ofthis group are of great importance and significance in stratigraphy. The previous studies ofthese ferns are mainly morphological, with only a few concerning the in situ spores andsporangia. In recent years. the authors have carried out a research project on the in situreproductive organs of the Early Cretaceous ferns from/ basins of Inner Mongolia, Liaoning,Jilin and Heilongjiang of Northeast china. The study focuses on 35 species of 17 genera be-longing to 10 families. The present note briefly introduces the results of this study by listingsome representative species.

关键词： Northeast china Early Cretaceous Filicopsida in situ reproductive organs.

Response synchronization: New progress in brain-visual information processing

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Chinese science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry , institute of Atmospheric Physics , Chinese Academy of sciences , {2. 10002., china 2. Commission of the National natural science Foundation of china , {2. 100083, china 3. The Center of Information science , Peking University, {2. 100871, china 4. Open Laboratory of Visual Information Processing , institute of Biophysics , Chinese Academy of sciences , beijing 100101, china State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National natural science Foundation of{2. Beijing China The Center of Information science Peking University Beijing China Open Laboratory of Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

DESIGN OF FARMLAND GIS FOR PRECISION AGRICULTURE

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Chinese geographical science 2003年第1期13卷 20-24页

作者： AN Kai, XIE Gao-di, LENG Yun-fa, XIAO Yu (institute of geographical {2.s and natural resources research, the Chinese Academy of {2.s, beijing 100101, P. R. china) institute of geographical {2.s and natural resources research the Chinese Academy of Sciences Beijing 100101 P. R. China

Precision Agriculture, also known as Precision Farming, or Prescription Farming, is a modern agriculture technology system, which brings ' precision' into agriculture system. All concepts of Precision Agriculture are established on the collection and management of variable cropland information. As the tool of collecting, managing and analyzing spatial data, GIS is the key technology of integrated Precision Agriculture system. This article puts forward the concept of Farmland GIS and designs Farmland GIS into five modules, and specifies the functions of the each module, which builds the foundation for practical development of the software. The study and development of Farmland GIS will propel the spreading of Precision Agriculture technology in china.

关键词： precision agriculture farmland GIS site-specific crop management prescription map

Vegetation and soil carbon storage in china

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science china Earth sciences 2004年第1期47卷 49-57页

作者： LI Kerang, WANG Shaoqiang & CAO Mingkuiinstitute of geographic {2.s and natural resources research, Chinese Academy of {2.s, beijing 100101, china Department of Geography, Maryland University, College Park,MD 2.742. USA Correspondence should be addressed to Li Kerang Inst. of Geogr. Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China Department of Geography Maryland University College Park MD 20742 United States

This study estimated the current vegetation and soil carbon storage in china using a biogeochemical model driven with climate, soil and vegetation data at 0.5°latitude-longitude grid spatial resolution. The results indicate that the total carbon storage in china's vegetation and soils was 13.33 Gt C and 82.65 Gt C respectively, about 3% and 4% of the global total. The nationally mean vegetation and soil carbon densities were 1.47 kg C/m2.and 9.17 kg C/m2. respectively, differing greatly in various regions affected by climate, vegetation, and soil types. They were generally higher in the warm and wet Southeast china and Southwest china than in the arid Northwest china; whereas vegetation carbon density was the highest in the warm Southeast china and Southwest china, soil carbon density was the highest in the cold Northeast china and southeastern fringe of the Qinghai-Tibetan Plateau. These spatial patterns are clearly correlated with variations in the climate that regulates plant growth and soil organic matter decomposition, and show that vegetation and soil carbon densities are controlled by different climatic factors.

关键词： carbon storage, vegetation, soil, china.

Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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science china Earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2.& ZHENG Du1 1. institute of geographic {2.s and natural resources research, Chinese Academy of {2.s, beijing 100101, china 2. Graduate School of the Chinese Academy of {2.s, beijing 100039, china 3. College of resources and Environment, Southwest Agricultural University, Chongqing 400716, china 4. The Ministry of {2. and Technology, P. C. china, beijing 100862. china 5. Chengdu institute of Biology, Chinese Academy of {2.s, Chengdu 610041, china 1. institute of geographic {2.s and natural resources research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese Academy of sciences 100039 Beijing China 3. College of resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of science and Technology P. C. China 100862 Beijing China 5. Chengdu institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

Effective solutions to a global 3D visual system in networking environments

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science china Earth sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2. ZHANG Yan3, YANG Chongjun2. LIU Suhong1, REN Yingchao2. RUI Xiaoping2.& LIU Donglin2.1. State Key Laboratory of Remote Sensing sciences, School of Geography and Remote Sensing, beijing Normal University, beijing 100875, china 2. State Key Laboratory of Remote Sensing sciences, institute of Remote Sensing Applications, Chinese Academy of sciences, beijing 101001, china 3. institute of geographical sciences and {12. resources research, Chinese Academy of sciences, beijing 101001, china 1. State Key Laboratory of Remote Sensing sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. Chinese Academy of sciences State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. institute of geographical {2.s and natural resources research Chinese Academy of Sciences 101001 Beijing China

The development of Web-based global 3D visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet