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remote sensing based shrub above-ground biomass and carbon storage mapping in Mu Us desert,{2.

science china(Technological sciences) 2010年第S1期53卷 176-183页

作者： XU Min 1,2.CAO ChunXiang 1,TONG QingXi 1,LI ZengYuan 3,ZHANG Hao 1,HE QiSheng 1,2.GAO MengXu 1,2.ZHAO Jian 1,2.ZHENG Sheng 1,2.CHEN Wei 1,2.& ZHENG LanFen 1 1state key {2. of remote sensing science,Jointly Sponsored by the Institute of remote sensing Applications of Chinese Academy of sciences and Beijing Normal University,Beijing 100101,china 2.Graduate School of the Chinese Academy of sciences,Beijing 10004.,china 3 Research Institute of Forest Resources and Information Techniques,Chinese Academy of Forestry,Beijing 10009,china 1. state key {2. of remote {4. science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China 2. Graduate School of the Chinese Academy of sciences Beijing 100049 China 3. Research Institute of Forest Resources and Information Techniques Chinese Academy of Forestry Beijing 10009 China

The estimation of above-ground biomass(AGB) and carbon storage is very important for arid and semi-arid ***-1A/B satellite data combined with field measurement data was used for the estimation of shrub AGB and carbon storage in the Mu Us desert,*** correlations of shrub AGB and spectral reflectance of four bands as well as their combined vegetation indexes were respectively analyzed and stepwise regression analysis was employed to establish AGB prediction *** prediction equation based on ratio vegetation index(RVI)was proved to be more suitable for shrub AGB estimation in the Mu Us desert than *** AGB and carbon storage were mapped using the RVI based prediction model in *** statistics showed the western Mu Us desert has relatively high AGB and carbon storage,and that the gross shrub carton storage in Mu Us desert reaches 16 799 2.0 t,which has greatly contributed to the carbon fixation in northern china.

关键词： above-ground biomass carbon storage Mu Us desert HJ-1A/B remote 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, Institute of Geographic {2.s and Natural Resources Research, Chinese Academy of {2.s, Beijing 100101, china 2. state key laboratory of Water Resources & Hydropower Engineering {2.s, 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.s 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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Characterization of plastic flow in two Zr-based bulk metallic glasses

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science china(Technological sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2. ZHANG Taihua1, LI Weihuo3 & WEI Bingchen3 1. state key {2. of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sci- ences, Beijing 100080,{4. 2. College of Physics and Electronic Information science, Tianjin Normal University, Tianjin 300074.{4. 3. National Microgravity {2., Institute of Mechanics, Chinese Academy of sciences, Beijing 100080,{4. 1. state key {2. of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China 2. College of Physics and Electronic Information science Tianjin Normal University Tianjin 300074 China 3. National Microgravity laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.

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Monitoring Glacier and Supra-glacier Lakes from Space in Mt. Qomolangma Region of the Himalayas on the Tibetan Plateau in china

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Journal of Mountain science 2009年第3期6卷 211-220页

作者： YE Qinghua ZHONG Zhenwei KANG Shichang Alfred Stein WEI Qiufang LIU Jingshi key laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences (CAS) Beijing 100085 China state key {2. of remote {4. science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China International Institutefor Geo-Information science and Earth Observation (ITC) PO Box 67500 AA Enschede The Netherlands

Because of the large number and remoteness, satellite data, including microwave data and optical imagery, have commonly been used in alpine glaciers surveys. Using remote {2. and Geographical Information System （GIS） techniques, the paper presents the results of a multitemporal satellite glacier extent mapping and glacier changes by glacier sizes in the Mt. Qomolangma region at the northern slopes of the middle Himalayas over the Tibetan Plateau. Glaciers in this region have both retreated and advanced in the past 35 years, with retreat dominating. The glacier retreat area was 3.2. km2.（or o.75 km^2.yr^-1 during 1974.and 1976, 8.68 km^2.（or 0.36 km^2.yr^-1 during 1976 and 1992. 1.4. km^2.（or 0.12.km^2.yr^-1） during 1992.2.oo. 1.14.km^2.（or 0.2. km^2.yr^-1 during 2.00-2.03, and 0.52.km^2.（or 0.07 km^2.yr^-1 during 2.03-2.08, respectively. While supra-glacier lakes on the debris-terminus of the Rongbuk Glacier were enlarged dramatically at the same time, from 0.05 km^2.in 1974.increased to 0.71 km^2.in 2.08, which was more than 13 times larger in the last 35 years. In addition, glacier changes also showed spatial differences, for example, glacier retreat rate was the fastest at glacier termini between 54.0 and 5700 m a.s.l than at other elevations. The result also shows that glaciers in the middle Himalayas retreat almost at a same pace with those in the western Himalayas.

关键词： Glacier lake remote sensing Mr. Qomolangma region Himalayas Tibetan Plateau

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Winter heat budget in the Huanghai Sea and the effect from Huanghai Warm Current (Yellow Sea Warm Current)

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Acta Oceanologica Sinica 2011年第5期30卷 56-63页

作者： QIAO Lulu WANG Xiaohua WANG Yongzhi WU Dexing BAO Xianwen MU Lin key laboratory of Seafloor {2. and Exploration Technology Ocean University of China Qingdao 266100 China key laboratory of Physical Oceanography Ministry of Education Ocean University of China Qingdao 266100 China School of Physical Environmental and Mathematical Sciences University of New South Wales at Australian Defence Force Academy Canberra Australia state key {2. of Satellite Ocean Environment Dynamics Second Institute Oceanography State Oceanic Administratim Hangzhou 310012 China The First Institute of Oceanography State Oceanic Administration Qingdao 266061 China National Marine Data and Information Service State Oceanic Administration Tianjin 300171 China

Four sources of surface heat flux （SHF） and the satellite remote sensing sea surface temperature （SST） data are combined to investigate the heat budget closure of the Huanghai Sea （HS） in *** is found that heat loss occurs all over the HS during winter and the area averaged heat content change decreases with a rate of-106 W/m *** with the area averaged SHF of-150 W/m 2.from the four SHF data sets,it can be concluded that the SHF plays a dominant role in the HS heat budget during *** contrast,the heat advection transported by the Huanghai Warm Current （Yellow Sea Warm Current,HWC） accounted for up to 2.% of the HS heat content *** correlation,especially in February,between the storm events and the SST increase demonstrates that the HWC behaves strongly as a wind-driven compensation current.

关键词： heat budget Huanghai Sea and Bohai Sea surface heat flux Huanghai Warm Current (Yellow Sea Warm Current)

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Research on Wireless Sensor Node for Measurement of Vegetation Structure Parameters

Research on Wireless Sensor Node for Measurement of Vegetati...

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亚洲精细农业与计算机农业应用联合大会

作者： QU Yonghua 1 SUN Gang 2.1. state key {2. of {4. sensing science Jointly Sponsored by Beijing Normal University and the Institute of {4. sensing Applications of Chinese Academy of sciences Beijing china. 100875 2. College of Information and electric engine china Agriculture University Beijing china. 100083

Based on WSN（Wireless Sensor Network）technology, this article designed a wireless sensor network node for vegetation parameter’s measurement, which can be used at large space scale and in long temporal series measurement activity. Preliminary validation of the wireless sensor network node’s algorithm and performance are presented in this article. The results indicated that the algorithm can estimate the vegetation parameters accurately from the measurement of transmittance of radiance through the canopy. The relative error of estimated LAI（Leaf Area Index） is 5%, and the LIDF（Leaf Inclination Distribution Function）agree with that of real vegetation structure basically. The sensitivity of designed wireless sensor network node is tested by measuring transmitted light intensity of projected direct LED light to leaves which have been punched with different density hole. The results indicted that the measured transmittance of leaves has high correlation with the holes density though it was also found that value of the former was slightly lower than that of the latter.

关键词： Wireless sensor node vegetation Structure parameters

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Spectral response of rice(Oryza sativa L.) leaves to Fe^(2.) stress

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science china(Life sciences) 2009年第8期52卷 747-753页

作者： CHI GuangYu1,2.CHEN Xin1,SHI Yi1 & LIU XinHui3 1 key laboratory of Terrestrial Ecological Process,Institute of Applied Ecology,Chinese Academy of {2.s,Shenyang 110016,{4. 2.Graduate School of Chinese Academy of {2.s,Beijing 10004.,{4. 3 state key Joint laboratory of Environmental Simulation and Pollution Control,School of Environment,Beijing Normal University,Beijing 100875,{4. key laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of sciences Beijing 100049 China state key Joint {2. of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

In the management of lake eutrophication,the regulation effect of Fe is considered,in addition to the controlling nitrogen-and phosphorus *** on the "Fe hypothesis",this paper tentatively applied plant spectral response to the remote sensing early-warning mechanism of lake eutrophication.A {2. water culture experiment with rice(Oryza sativa L.) was conducted to study Fe uptake by plants and the chlorophyll concentration and visible-near infrared spectrum of vegetable leaves as well as their interrelations under Fe2. *** spectral indices,i.e.,A1(integral value of the changes of spectral reflectivity in the range 4.0―670 nm under Fe2. stress),A2.integral value of the changes of spectral reflectivity in the range of 760―1000 nm under Fe2. stress) and S(blue-shift range of red edge curve under Fe2. stress),were used to establish quantitative models about the relationships between the rice leaf spectrum and Fe2. *** the increase of Fe2. in a culture solution,the Fe content in rice plants increased,while the chlorophyll concentration in vegetative leaves *** spectral reflectivity of vegetable leaves increased in the visible light band but decreased in the near infrared band,and the blue-shift range of the red edge curve *** indices A1,A2.and S all had significant correlations with the Fe content in rice leaves,the correlation coefficient being respectively 0.951(P 2.> 0.96) and predict the Fe level in rice leaves.

关键词： rice(Oryza sativa L.) spectrum Fe2. lake eutrophication

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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, Beijing Normal University, Beijing {2., china National Satellite Meteorological Center, china Meteorological Administration, Beijing 100081, china 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, Beijing,{2. 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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Recent research and applications of GPS based technology for bridge health monitoring

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science china(Technological sciences) 2010年第10期53卷 2597-2610页

作者： YI TingHua1,2. LI HongNan1 & GU Ming2.1 Faculty of Infrastructure Engineering, Dalian University of Technology, Dalian 11602., china 2.state {2. laboratory for Disaster Reduction in Civil Engineering, Tongji University, Shanghai 2.0092. china 1. Faculty of Infrastructure Engineering Dalian University of Technology Dalian 116023 China2. State Key Laboratory for Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China

Today,long-span bridges are being designed to be more flexible and to resist extensive impacts from changes in temperature,severe wind gusts and earthquake tremors. Structural responses (especially displacement) of bridge structures are becoming increasingly important for the finite element (FE) modal updating,structural response prediction and safety evaluation. Methods of global displacement sensing were developed for these needs. This paper presents an overview of current research and development activities in the field of bridge health monitoring using the global positioning system (GPS). The GPS monitoring technology and its accuracy assessment method are also briefly described. Finally,existing problems and promising research efforts in the GPS based bridge health monitoring are discussed.

关键词： global positioning system (GPS) structural health monitoring (SHM) bridge measurement

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The accuracy assessment in areal interpolation:An empirical investigation

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science china(Technological sciences) 2008年第S1期51卷 62-71页

作者： LIU XiaoHang1 & LIU Yu2.1 Department of Geography & Human Environmental Studies,San Francisco state University,San Fran-cisco,CA 94.32.USA 2.Institute of {4. {2. and Geographical Information Systems,Peking University,Beijing 100871,china Department of Geography & Human Environmental Studies San Francisco State University San Francisco CA 94132 USA Institute of remote sensing and Geographical Information Systems Peking University Beijing 100871 China

Areal interpolation is the process of transferring data from source zones to target zones. While method development remains a top research priority in areal interpo-lation,the accuracy assessment aspect also begs for attention. This paper reports an empirical experience on probing an areal interpolation method to highlight the power and potential pitfalls in accuracy assessment. A kriging-based interpolation algorithm is evaluated by several approaches. It is found that accuracy assessment is a powerful tool to understand an interpolation method,e.g. the utility of ancillary data and semi-variogram modeling in kriging in our case study. However,different assessment methods and spatial units on which assessment is conducted can lead to rather different results. The typical practice to assess accuracy at the source zone level may overestimate interpolation accuracy. Assessment at the target zone level is suggested as a supplement.

关键词： areal interpolation accuracy assessment area-to-point kriging

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