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Using hyperspectral indices to estimate foliar chlorophyll a concentrations of winter wheat under yellow rust stress

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Using hyperspectral indices to estimate foliar chlorophyll a...

The First International Conference on Computers and Computing Technologies in Agriculture

作者： LI JING~(1,2) JIANG JINBAO~1 CHEN YUNHAO~(1,2,*) WANG YUANYUAN~1 SU WEI~3.HUANG WENJIANG~4 1 College of Resources Science and Technology beijing Normal University No.19 Xinjiekouwai Street beijing 100875,china 2 State {3. laboratory of Earth Surface Processes and Resource Ecology beijing Normal University No.19 Xinjiekouwai Street beijing 100875,china 3.College of Information & Electrical Engineering china Agricultural University beijing 100083.china 4 National Engineering Research Center for Information Technology in Agriculture beijing 100089,china

The canopy hyperspectral reflectance of winter wheat infected with yellow rust at different levels of severity were measured by an ASD FieldSpec Pro FR spectrometer in the field and the concentrations of chlorophyll a(Chl a) in the leaves corresponding to the spectra were determined by biochemical methods in the *** analyses were made between Chl a concentrations and canopy hyperspectral data of diseased wheat. Results show that foliar Chl a concentrations are strongly correlated with canopy spectrum in the visible region and the first-order derivative spectrum in blue edge,green edge,and red *** and nonlinear models for estimating Chl a concentrations of the diseased wheat were built based on several spectral *** indicate that SDr/SDg,in which SDr and SDg are the sums of the first derivative within red and green edges,outperformed the other indices in predicting Chl a *** relative estimation errors for Chl a for 12 unseen samples are 17.5%.It is concluded that derivative spectra in red edge and green edge have strong prediction power for foliar Chl a concentrations of diseased winter *** hyperspectral remote sensing data to monitor crop disease and nutrition status is very promising.

关键词： chlorophyllα estimation models hyperspectral wheat yellow rust stress

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黄河流域坡高地系统最小生态需水研究

山地学报 2004年第2期22卷 154-160页

作者：张远杨志峰北京师范大学环境学院北京师范大学环境学院水环境模拟国家重点实验室水沙科学教育部重点实验室北京 100875 中国环境科学研究院北京 100012水环境模拟国家重点实验室水沙科学教育部重点实验室北京 100875

以保护和恢复流域坡高地生态系统为目的,对坡高地最小生态需水问题进行研究,提出了坡高地生态需水和生态缺水的计算方法。以黄河流域为实例,在GIS和遥感技术支持下对坡高地最小生态需水量和缺水量进行了计算,并从时空两个尺度揭示了黄... 详细信息

以保护和恢复流域坡高地生态系统为目的,对坡高地最小生态需水问题进行研究,提出了坡高地生态需水和生态缺水的计算方法。以黄河流域为实例,在GIS和遥感技术支持下对坡高地最小生态需水量和缺水量进行了计算,并从时空两个尺度揭示了黄河流域坡高地生态系统最小生态需水的变化规律,研究成果可为流域生态环境建设和水资源合理配置提供依据。

关键词：生态需水坡高地系统时空变化黄河流域

Incremental Study Based on Support Vector Used to Anomaly Detection for Hyperspectral Imagery

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Incremental Study Based on Support Vector Used to Anomaly De...

2010 International Conference on remote sensing (ICRS 2010)

作者： Liyan Zhang1 Derong Chen2 Yonghua Sun1 1.key laboratory of 3. Information Acquisition and Application of the Ministry of Education key laboratory of Integrated Disaster Assessment and Risk Governance of the Ministry of Civil Affairs key laboratory of Resource environment and GIS of beijing. Capital Normal University 2. College of Mechanical and Electrical Engineering beijing Institute of Technology beijing Peoples R china

While detecting anomalies in hyperspectral imagery with support vector data description （SVDD）, large numbers of operation was run because of the high dimension character of dataset and the complexity of background and the high miss rate was discovered because of the interfered background by interior anomalies. This paper used incremental support vector data description （ISVDD） method that samples are divided many sub- sample, and incremental study is designed to simplify the computation. On every sub-sample study, optimization is needed according of the support vectors obtained from above sub-sample and current sub-sample data. By the experiment on the HYMAP data, computation complexity of the algorithm decrease obviously and the computation speed increase highly under the similar detection effect compared with SVDD algorithm.

关键词： hyperspectral imagery anomaly detection incremental support vector data description

Characteristics of Earthquake-Triggered Landslides and Post-Earthquake Debris Flows in Beichuan County

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Journal of Mountain Science 2010年第3期7卷 246-254页

作者： ZHUANG Jianqi CUI Peng HU Kaiheng CHEN Xiaoqing GE Yonggang key laboratory of Mountain Hazards and Land Surface Processes and Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu 610041 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Field investigations and aerial photography after the earthquake of May 12, 2008 show a large number of geo-hazards in the zone of extreme earthquake effects. In particular, landslides and debris flows, the geo-hazards that most threaten post-disaster reconstruction, are widely distributed. We describe the characteristics of these geo-hazards in Beichuan County using high-resolution remote sensing of landslide distribution, and the relationships between the area and volume of landslides and the peak-discharges of debris flows both pre- and post-earthquake. The results show： 1） The concentration （defined as the number of landslide sources per unit area： Lc） of earthquake- triggered landslides is inversely correlated with distance from the earthquake （DF） fault. The relationship is described by the following equation： Lc = 3.2264exp（-0.083.DF）（R2 = 0.9246）; 2） 87 % of the earthquake-triggered landslides were less than 15× 10^4 m2 in area, and these accounted only for 5o% of the total area; 84% of the landslide volumes were less than 60×10^4 m3. and these accounted only for 50% of the total volume. The probability densities of the area and volume distributions are correlated： landslide abundance increases with landslide area and volume up to maximum values of 5 ×10^4m2 and 3. ×10^4 m3. respectively, and then decreases exponentially. 3. The area （AL） and volume （VL） of earthquake-triggered landslides are correlated as described with the following equation： VL=6.513.AL1.0227 （R2 = 0.923.）; 4）Characteristics of the debris flows changed after the earthquake because of the large amount of landslide material deposited in the gullies. Consequently, debris flow peak-discharge increased following the earthquake as described with the following equation： Vpost = 0.8421Vprel-0972 （R2 = 0.9821）（Vpre is the peak discharge ofpre-earthquake flows and the Vpost is the peak discharge of post-earthquake flows）. We obtained the distribution of the landslides based on the above anal

关键词： 5.12 earthquake Landslide Debris flow Magnitude Beiehuan County

The Monitoring of Eco-environment Quality Trends and Analysis of Driving Factor of beijing:RS ＆ GIS Application Research

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The Monitoring of Eco-Environment Quality Trends and Analysi...

中国地理学会百年庆典

作者： Liu Hongqi~(a,b,c),Gong Huili~(a,b,c),Hu Zhuowei~(a,b,c) a College of Resources environment and Tourism,Capital Normal University b key Lab of 3. Information and Acquisition and Application,MOE,beijing,{3. c beijing Municipal Lab of Resources environment and GIS,beijing,china

＜正＞TM,SPOT and QuickBird images of 2000～2008 were taken as data *** remote sensing（RS） and Geographical Information System（GIS） technology, combined with field survey and other auxiliary data, ecological information,including vegetation,land,water resources,air quality,and so on,were ***, the qualitative and quantitative analysis of the spatial and temporal distribution of various eco-environmental factors was made to determine the main features that impact the eco-environment.

关键词： remote sensing Geographical Information System eco-environment quality assessment eco-environmental status index

基于iPlanet技术的数字影像电子商务系统的研究

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计算机工程与应用 2002年第5期38卷 204-206页

作者：窦静晏磊常炳国北京大学遥感与地理信息系统研究所北京100871 北京市空间信息集成与3.工程应用重点实验室北京100871

开发了一个电子商务网站系统,用于在线冲印数字影像。在充分论证了几种电子商务解决方案优缺点基础上,详细分析了该系统的需求、实现功能,采用了目前通用的三层系统,应用服务器层采用iPlanet中间件技术。论文重点讨论iPlanet中间件技术... 详细信息

开发了一个电子商务网站系统,用于在线冲印数字影像。在充分论证了几种电子商务解决方案优缺点基础上,详细分析了该系统的需求、实现功能,采用了目前通用的三层系统,应用服务器层采用iPlanet中间件技术。论文重点讨论iPlanet中间件技术的特征及其在电子商务系统应用中的优越性。

关键词：电子商务系统数字影像 iPlanet技术中间件

Empirical-Statistical Models Based on remote sensing for Estimating the Volume of Landslides Induced by the Wenchuan Earthquake

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Journal of Mountain Science 2011年第5期8卷 711-717页

作者： FAN Jianrong LI Xiuzhen GUO Fenfen GUO Xiang key laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment CAS Chengdu 610041 China

The Wenchuan Ms 8.0 earthquake on May 12, 2008 induced a huge number of landslides. The distribution and volume of the landslides are very important for assessing risks and understanding the landslide - debris flow - barrier lake - bursts flood disaster chain. The number and the area of landslides in a wide region can be easily obtained by remote sensing technique, while the volume is relatively difficult to obtain because it requires some detailed geometric information of slope failure surface and sub-surface. Different empirical models for estimating landslide volume were discussed based on the data of 107 landslides in the earthquake-stricken area. The volume data of these landslides were collected by field survey. Their areas were obtained by interpreting remote sensing images while their apparent friction coefficients and height were extracted from the images unifying DEM (digital elevation model). By analyzing the relationships between the volume and the area, apparent friction coefficients, and the height, two models were established, one for the adaptation of a magnitude scale landslide events in a wide range of region, another for the adaptation in a small scope. The correlation coefficients (R2) are 0.7977 and 0.8913. respectively. The results estimated by the two models agree well with the measurement data.

关键词： 5.12 Wenchuan earthquake Landslides remote sensing Volume Estimation model

River Boundaries Extraction in Mountain Areas for SAR Images with Fusing GIS Information

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River Boundaries Extraction in Mountain Areas for SAR Images...

2011 CIE International Conference on Radar(RADAR 2011)

作者： Wang Xiaoliang 1 2 Li Chunsheng 2 and Wu Renbiao 1 3.1 Tianjin key laboratory for Advanced Signal Processing Civil Aviation University of china Tianjin 3.03.0 P.R.{3. 2 School of Electronics and Information Engineering Beihang University beijing 100191 {3. 3.Defence key laboratory for ATR Shenzhen University Shenzhen 518060 {3.

River boundaries extraction on SAR images is valuable for flood monitoring. Traditional methods usually failed in high relief areas. We proposed a river boundaries extraction method to conquer the difficulty to discri... 详细信息

关键词： SAR Information Fusion Segmentation Active Contour Model Level Set

Dynamic analysis of evapotranspiration based on remote sensing in Yellow River Delta

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Journal of Geographical Sciences 2003年第4期13卷 408-415页

作者： PAN Zhiqiang, LIU Gaohuan, ZHOU Chenghu(State key laboratory of Resource and environment Information System, Institute ofGeographic Sciences and Natural Resources Research, CAS, {3. 100101, china) Institute of Geographic Sciences and Natural Resources Research CAS State Key Laboratory of Resource and Environment Information System 北京 Institute of Geographic Sciences and Natural Resources Research CAS State Key Laboratory of Resource and Environment Information System 北京 100101

Evapotranspiration (ET) is an important parameter for water resource management. Compared to the traditional ET computation and measurement methods, the ET computation method based on remote sensing has the advantages of quickness, precision, raster mapping and regional scale. SEBAL, an ET computation model using remote sensing method is based on the surface energy balance equation which is a function of net radiance flux, soil heat flux, sensible heat flux and latent heat flux. The former three fluxes can be computed through the parameters retrieved from remote sensing image, then the latent heat flux can be obtained to provide energy for ET. Finally we can obtain the daily ET. In this study SEBAL was applied to compute ET in the Yellow River Delta of china where water resource faces a rigorous situation. Three Landsat TM images and meteorology data of 1999 were used for ET computation, and spatial and temporal change patterns of ET in the Yellow River Delta were analysed.

关键词： evapotranspiration remote sensing Yellow River Delta