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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 Laboratory 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 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 （{3.） 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 3. 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 0.3. 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 3. 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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基于分形特征的网络异常检测方法研究

计算机工程与应用 2004年第22期40卷 34-36页

作者：刘峰胡昌振帅艳民北京理工大学机电工程学院北京100081 北京师范大学地理与遥感科学学院北京100875

网络连接同许多其它现象一样,呈现出一种统计自相似性。论文根据此特征提出了一种基于分形特征的网络异常检测方法,该方法能够根据网络连接分形维数的变化,有效地检测网络拒绝服务攻击和端口扫描等异常情况,并通过模拟实验证明了该方法... 详细信息

网络连接同许多其它现象一样,呈现出一种统计自相似性。论文根据此特征提出了一种基于分形特征的网络异常检测方法,该方法能够根据网络连接分形维数的变化,有效地检测网络拒绝服务攻击和端口扫描等异常情况,并通过模拟实验证明了该方法的可行性。

关键词：网络安全分形自相似

Bi-directional normalized difference vegetation index: concept and application

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Progress in Natural Science:Materials International 2002年第2期 37-41页

作者： LI Xiaowen , GAO Feng , WANG Jindi , YANG Hua, A. STRAHLER and C. SCHAAF( Research Center for remote sensing and Department of Geography, {2. {3. {4., beijing 100875, China Department of Geography and Center for remote sensing, Boston {4., Boston MA02.15, USA) Research Center for remote sensing and Department of Geography，{2. {3. {4.，{2. 100875，China Department of Geography and Center for remote sensing，Boston {2.，Boston MA02.15，USA Department of Geography and Center for remote sensing，Boston {2.，Boston MA02.15，USA Research Center for remote sensing and Department of Geography，{2. {3. {4.，{2. 100875，China

The data products of land surface bi-directional reflectance distribution function (BRDF) from the space-borne Polarization and Directionality of the Earth Reflectance (POLDER) of France and the Moderate Resolution Imaging Spectroradiometer (MODIS) of USA are available recently, but the atmospheric correction for meeting the requirement of quantitative remote sensing is still a very difficult problem. This paper presents a concept: bi-directional {2.ized difference vegetation index (Bi-NDVI), in order to consider simultaneously the effects of both land surface BRDF and atmospheric path scattering. An atmospheric quality index is thus defined for satellite multi-angular observations. The quality of MODIS/BRDF data products can be improved notably through iterative inversion weighed by this index.

关键词： bi-directional reflectance normalized difference vegetation index atmospheric correction.

A preliminary knowledge-driven prediction model of snail distribution in the Poyang Lake region

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Chinese Science Bulletin 2008年第1期53卷 115-123页

作者： ZHAO An1,2.3.& BAO ShuMing1 1 The Key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi normal university, Nanchang 3.002., China 2.Institute of Geographic Sciences and Resources Research, Chinese Academy of Sciences, {2. 100101, China 3.School of Geography and Environmental Sciences, Jiangxi normal university, Nanchang 3.002., China

Present monitoring and prediction of schistosomiasis’s intermediate parasite, snail, are based on re-mote sensing image’s spectral signatures, and the calculation result is in fact an incom-plete-constraints solution. TM image of the Poyang Lake region on October 3., 2.05 was combined with gis thematic data (DEM, boundary of the Poyang Lake, vegetation, soil and land use) to make a prediction on snail spatial distribution in the region by {2. sensing, geo-informatics and knowl-edge-driven modeling according to mechanism of snail occurrence. Result shows that with change of overall fuzzy membership of snail occurrence from high to low, snail occurrence of the snail samples of validation group goes up to 81% within 10% high fuzzy membership range, denoting high efficiency of the model in predicting snail occurrence.

关键词：鄱阳湖区域蜗牛分布模糊分类血吸虫病

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

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

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 Sciences, beijing,China. 2.State Key Laboratory of remote {2. Science and Research Center for remote {2. and gis,beijing normal university,beijing,China.

[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.

关键词：

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东北漫岗黑土区春季冻融期浅沟侵蚀

山地学报 2006年第3期24卷 306-311页

作者：张永光伍永秋刘宝元北京师范大学沙漠与沙区资源研究所北京师范大学环境演变与自然灾害教育部重点实验室北京师范大学地理与遥感科学学院

浅沟侵蚀是东北漫岗黑土区农耕地上常见的水蚀类型,往往对坡耕地造成严重的破坏。2.05年春季,通过对两个小流域浅沟侵蚀的调查测量,发现该区浅沟侵蚀相当严重,两流域分别形成浅沟14.、16条,浅沟总长度分别达3.2.9 m、2.14. m,浅沟密度... 详细信息

浅沟侵蚀是东北漫岗黑土区农耕地上常见的水蚀类型,往往对坡耕地造成严重的破坏。2.05年春季,通过对两个小流域浅沟侵蚀的调查测量,发现该区浅沟侵蚀相当严重,两流域分别形成浅沟14.、16条,浅沟总长度分别达3.2.9 m、2.14. m,浅沟密度分别为908 m/km2.766 m/km2.侵蚀深度分别为0.17 mm、0.16 mm,侵蚀模数分别达181.8 t/km2.173.6 t/km2.2.05年春季两流域浅沟侵蚀期的径流深分别是6.8 mm、7.7 mm。分析表明,研究区在春季表层土壤解冻、地表裸露和存在季节性冻土层的条件下,春季融雪及强降水易造成强烈的浅沟侵蚀。在分布上,浅沟一般位于坡面的中下部,而且多发育在瓦背状坡面的集流水路上。另外,耕作措施对浅沟的形成和发展也有重要影响。

关键词：黑土区强降水冻融浅沟侵蚀

Eco-Environmental Vulnerability Evaluation in the Yellow River Basin,China

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Pedosphere 2008年第2期18卷 171-182页

作者： WANG Si-Yuan LIU Jing-Shi YANG Cun-Jian Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 （China） Institute of Electronics Chinese Academy of Sciences Beijing 100080 （China） Centre of RS and gis Applications Sichuan Normal University Chengdu 610066 （China）

Using remote sensing(RS)data and geographical information system({2.),eco-environmental vulnerability and its changes were analyzed for the Yellow River Basin,*** objective of this study was to improve our understanding of eco-environmental changes so that a strategy of sustainable land use could be *** environmental numerical model was developed using spatial principal component analysis(SPCA)*** model contains twelve factors that include variables of land use,soil erosion,topography,climate,and *** this model,synthetic eco- environmental vulnerability index(SEVI)was computed for 1990 and 2.00 for the Yellow River *** SEVI was classified into six levels,potential,slight,light,medium,heavy,and very heavy,following the natural breaks classification. The eco-environmental vulnerability distribution and its changes over the ten years from 1990 to 2.00 were analyzed and the driving factors of eco-environmental changes were *** results show that the eco-environmental vulnerability in the study area was at medium level,and the eco-environmental quality had been gradually improved on the ***,the eco-environmental quality had become worse over the ten years in some *** the study area,population growth,vegetation degradation,and governmental policies for eco-environmental protection were found to be the major factors that caused the eco-environmental changes over the ten years.

关键词： eco-environmental vulnerability geographic information system (gis) remote sensing (RS) spatial principal component analysis Yellow River Basin

EXTRACTION OF BIOCHEMICAL COMPONENTS IN WINTER WHEAT BY CANOPY HYPERSPECTRUM

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EXTRACTION OF BIOCHEMICAL COMPONENTS IN WINTER WHEAT BY CANO...

基于Multigen/Vega的校园VR仿真系统的实现——以中国矿业大学为例

Progress of Information Technology in Agriculture

作者： Huang Wenjiang Wang Jihua Liu Liangyun Zhao Chunjiang Huang Muyi Wang JindiNational Engineering Research Center for Information Technology in Agriculture beijing Post Code:100089 ChinaResearch Center for remote {2. and {3. beijing normal university beijing Post Code:100875 China

＜正＞ Winter wheat canopy spectrum is affected by wheat canopy （leaf area index, leaf biochemical components, leaf angle distribution,canopy shadows, et al.）, soil, weeds, environment and their interactions. So the uncertainties for crop canopy spectral information become a fatal problem for the canopy biochemical and biophysical variables extraction. Recent studies have demonstrated the application of spectral indices from hyperspectral data for crop biochemical and biophysical variables. These indices are the compositive response to variations of several vegetation and environmental properties. Canopy chlorophyll content, an indicator of photosynthesis activity, which is related the nitrogen concentration in green vegetation and serves as a measure of the crop response to nitrogen application. The combination of NDVI and PRI can reduce the effect of LAI and soil background. The index （CCII） was proved to be sensitive to chlorophyll concentration and very resistant to the variations. This paper introduced the application of the ratio TCARI/OSAVI to make accurate predictions of winter wheat chlorophyll content under different varieties, and the application of SIPI for canopy biochemical indicators inversion by minimizing foliar inner structure effect. It indicated that the canopy chlorophyll content and nitrogen concentration could be evaluated by some new combination vegetation indices.

关键词： winter wheat canopy spectrum uncertainties information extraction

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系统仿真学报 2004年第9期16卷 1995-1998页

作者：宋金玲肖寒盛业华王锦地北京师范大学地理学与遥感科学学院遥感与地理信息系统研究中心遥感科学国家重点实验室环境遥感与数字城市北京市重点实验室北京100875 中国矿业大学环测学院徐州221008 南京师范大学地理科学学院南京210097

虚拟现实技术对于城市规划和城市的可持续发展有着非常重要的意义,它的长足进步,为真实景观的再现提供了有效手段。本论文在已有的二维地理信息系统数据的基础上进行校园数据的获取与组织,利用虚拟现实技术实现校园全景的三维重建,采用... 详细信息

虚拟现实技术对于城市规划和城市的可持续发展有着非常重要的意义,它的长足进步,为真实景观的再现提供了有效手段。本论文在已有的二维地理信息系统数据的基础上进行校园数据的获取与组织,利用虚拟现实技术实现校园全景的三维重建,采用层次型与面向对象相结合的三维数据结构,构造了校园全景的仿真模型,并实现了校园全景的驱动显示,为校园规划和可持续发展更可靠的保证。

关键词：虚拟现实 Multigen Vega 仿真