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Estimation of regional evapotranspiration over Northwest china using {1. sensing

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Journal of Geographical Sciences 2001年第2期11卷 140-148页

作者： CHEN Yun-hao, LI Xiao-bing, SHI Pei-jun (Institute of Resources Science, beijing {1. {2., Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of{3., beijing 1.0875,{3.) Institute of Resources Science Beijing Normal University Key Laboratory of Environmental Change and Natural Disaster Ministry of Education of China

It is a very complicated problem to estimate evapotranspiration (ET) over a large area of land surface. In this paper, the evapotranspiration estimation models for dense vegetation and bare soil are presented, based on the information of parameters like vegetation cover-degree and surface albedo. Combined with vegetation cover-degree data, a model for regional evapotranspiration estimation over the heterogeneous landscape is derived. Through a case study using remote sensing data over Northwest{1., the accuracy of the model for regional evapotranspiration estimation is checked. The result shows that the accuracy of the model is satisfactory. The features of evapotranspiration over Northwest{1. are also discussed with the application of the model.

关键词： evapotranspiration remote sensing vegetation cover-degree Northwest china

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城市地理信息三维可视化研究

系统仿真学报 2003年第12期15卷 1771-1773,1777页

作者：张晶张峥嵘首都师范大学北京100037 南京理工大学理学院南京210094

讨论的城市地理信息系统三维可视化技术致力于将传统的地理信息系统和虚拟现实技术结合起来,通过对图形数据和属性数据库的共同管理、分析及操作,实现数据可视化,为城市管理和决策提供准确、及时、全面的信息、依据和手段,促进城市管理... 详细信息

讨论的城市地理信息系统三维可视化技术致力于将传统的地理信息系统和虚拟现实技术结合起来,通过对图形数据和属性数据库的共同管理、分析及操作,实现数据可视化,为城市管理和决策提供准确、及时、全面的信息、依据和手段,促进城市管理的规范和科学化。本文建立的三维可视化城市地理信息系统使用了细节层次(Level Of Detail, LOD)显示技术和视景分块调度技术来提高实时性。

关键词：地理信息系统三维可视化虚拟现实细节层次视景分块调度

gis-Based Assessment of Land Suitability for Optimal Allocation in the Qinling Mountains,{1.

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Pedosphere 2006年第5期16卷 579-586页

作者： LIU Yan-Sui WANG Jie-Yong GUO Li-Ying Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） Graduate School of Chinese Academy of Sciences Beijing 100039 （China） College of Tourism and Environmental Sciences Shaanxi Normal University Xi＇an 710062 （China）

A gis-based method was used to assess land suitability in the Qinling Mountains, Shaanxi Province of{1. through simultaneous consideration of physical features and current land use. Through interpretation of Landsat TM images and extensive field visits the area was modeled into 40 land types in five altitudinal zones (valleys and gullies, hillsides and terraces, foothills, mid-mountain, and sub-alpine mountain). Then, a suitability score was assigned to five physical factors (climate, hydrology, topography, soil, and vegetation). Next, their integrated overall suitability value scores were compared with the observed land cover to determine whether it should be reallocated a new use. Results showed that the five suitability classes of agriculture, forest, grassland, farmland-woodland, and scrub-pasture had altitudinal stratification and a total of 1.51.km2.(8.89%) of lands on the northern slopes of the Qinling Mountains had to be reallocated. To achieve this reallocation, 657 km2.of arable land should be reduced, and forest, grassland and scrub-pasture increased by 61. km2. 1.5} km2.and 405 km2. respectively. Implementation of these recommended land reallocations should help achieve suitable use of land resources and prevent land degradation.

关键词： gis landforms optimal allocation Qinling Mountains suitability evaluation

Identification of Hydroxyl Copper Toxicity to Barley(Hordeum Vulgare) Root Elongation in Solution Culture

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Identification of Hydroxyl Copper Toxicity to Barley(Hordeum...

中国地理学会百年庆典

作者： Wang Xuedong~(1.2.,Ma Yibing~2.Hua Luo~1.1.The Key Lab of Resource Environment and gis, College of Resource Environment & Tourism,Capital {3. {2.,beijing 1.003.,china 2.Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences, beijing 1.0081.china

The effect of pH on the acute toxicity of Cu to barley(Hordeum vulgare ) root elongation was investigated in solution *** results showed that the median effective concentrations(EC50s;i.e.,the concentration that reduced root elongation by 50%based on free Cu activity) were not significantly different in the low-pH range from 4.5 to 6.5,but in the high-pH range from 7.0 to 8.0,a significant effect of pH on EC50s was *** nonlinear relationship between EC50 and H activity in the present study indicated that the increased toxicity with increasing pH in solution may not be caused by decreasing H *** we take account of CuOH activities,a good linear relationship(r>0.97) between the ratio of CuOH activity to free Cu activity and acute Cu toxicity to barley root elongation was achieved,which indicated that the observed toxicity in the high pH range may be caused by CuOH plus free Cu in ***-regression analysis suggested CuOH had a greater binding affinity than Cu at the biotic ligand *** logistic dose-response curve showed that expressing the Cu dose as Cu+ {1.9{1.CuOH improved the data fit significantly compared to consideration of the free Cu activity ***,our results suggest CuOH was highly toxic to barley root *** enhanced toxicity of CuOH therefore needs to be considered when modeling the effect of pH on Cu toxicity to barley for exposures having pH greater than 6.5.

关键词： Hydroxyl copper pH Biotic ligand model

Matlab和C语言集成下的Oracle Spatial空间插值方法研究

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计算机工程与应用 2004年第22期40卷 165-167,176页

作者：屈永华刘素红王锦地焦思红北京师范大学遥感与地理信息系统中心北京100875 北京工业职业技术学院北京100042

基于Matlab提供的CAPI函数以及OracleSpatial空间数据管理模型,论文给出了在VisualC++环境下利用Matlab的插值函数对OracleSpatial下的离散点进行空间插值的详细步骤和应用实例。作者认为将C语言和Matlab结合起来实现对OracleSpatial空... 详细信息

基于Matlab提供的CAPI函数以及OracleSpatial空间数据管理模型,论文给出了在VisualC++环境下利用Matlab的插值函数对OracleSpatial下的离散点进行空间插值的详细步骤和应用实例。作者认为将C语言和Matlab结合起来实现对OracleSpatial空间对象的管理和操作,是实现快速开发gis应用程序的一条有效途径。

关键词：空间插值 Matlab C API Oracle Spatial

Design ＆ Implementation of Data Communication Server in Farming Machinery Supervision System

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Design ＆ Implementation of Data Communication Server in Far...

亚洲精细农业与计算机农业应用联合大会

作者： LIU Yongsheng 1.2.CHENG Liping 2.CHEN Tianen 2.YAO Guangqiang 2.1.ollege of Information Engineering Capital normal university {2. 1.003. china 2.ational Engineering Research Center for Information Technology in Agriculture {2. 1.0097 china

In order to supervise the working process of the remote farming machinery on a large scale, it is necessary to deal with the real-time data such as oil consumption, speed and location coordinates of many farming machines effectively. Because of the following reasons, the data communication server which takes the charge of data processing and communicating has always been the performance bottleneck of the farming machinery supervision system. The first reason is that the amount of real-time data is large and the second reason is that the processing of real-time data must be in time. This paper uses the object-oriented programming method to design and implement a data communication server which is based on the sockets communication, thread pool and I/O multiplexing. In this paper, the multi-connection TCP communication and the high-speed concurrency processing of large amount of real-time data are subtly resolved. The circular queue data structure, the multiple thread technology and I/O multiplexing are used in the server to accept, process and store the farming machines’ real-time data. The constant thread pool and temporary thread pool are used to provide data for monitoring centre which are used to display the farming machines’ working status and the result of statistical analysis. The expansive communication protocols of application layer are designed in this paper to increase the ability of the communication among different models in the farming machinery supervision system. The class hierarchy is built up to increase the ability of code reuse. The data communication server as a primary part of the farming machinery supervision system has been tested in {1. Xing Lu He Farming Machine Server Company. The result indicates that the server’s stability and the efficiency of the real-time data processing can meet the requirement to supervise the working process of the remote farming machinery on a large scale.

关键词： Data communication server Thread pool I/O Multiplexing Sockets Communication protocols

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...

2.1. International Conference on {1. Sensing (ICRS 2.1.)

作者： Liyan Zhang1.Derong Chen2.Yonghua Sun1.1.Key Laboratory of {1. 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 {2. 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

基于空间分析的机井管理系统总体设计及其关键技术探讨

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水文地质工程地质 2004年第1期31卷 101-104页

作者：赵祥张晔刘素红北京师范大学资源环境系遥感与gis研究中心北京100875 天津市龙脉水资源咨询中心天津300060

在gis空间分析技术支持下 ,对机井管理系统从总体设计、系统功能结构、数据库建库方法、系统实现等多方面进行了阐述 ,并探讨了系统开发的关键技术和主要的程序编码 ,在机井管理信息化方面进行了有益的尝试 ,为建立类似系统提供了一个... 详细信息

在gis空间分析技术支持下 ,对机井管理系统从总体设计、系统功能结构、数据库建库方法、系统实现等多方面进行了阐述 ,并探讨了系统开发的关键技术和主要的程序编码 ,在机井管理信息化方面进行了有益的尝试 ,为建立类似系统提供了一个应用范例。

关键词：空间分析机井管理系统设计数据库总体设计管理信息化地下水资源管理

Ecological Instream Flow Requirements Calculation of Pihe River by Montana Methodology in Sichuan Basin,china

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Ecological Instream Flow Requirements Calculation of Pihe Ri...

2.07中国科协年会

作者： W.Ouyang~(1.2. F.H.Hao~1.H.Chen~1.X.Wang~1.S.T.Yang~{1.1.School of Environment,State Key Laboratory of Water Environment Simulation,2.beijing {{1. {2. 2.International Institute for Geo-Information Science and Earth Observation(ITC),Netherlands {1.State Key Laboratory of remote Sensing Science,beijing Key Laboratory for remote Sensing of Environment and Digital Cities,School of Geography,beijing {{1. {2.

With the rapid economic developments in china,the future water resource developments should be sustainable and that a component of the natural flow of rivers should be reserved to ensure diverse ecological *** last 1. years,ecological instream flow requirements(EIFR)research of river was one of the main and hot fields for eco-hydrology *** this paper,we summarized the research advance of eco-hydrology and also,the conception of the EIFR was also followed and *** ecological instream flow has three main functions:maintain the water ecological environments,dilute pollutants and *** coordinate with the water resource allocation,we evaluated EIFR of Pihe River section in every 1.1.month of three typical years (1.68,1.86 and 1.87).Pihe River is one of the main waterr sources for the cities in Sichuan Basin and locates in the lower beach of famous Doujiang *** Montana methodology was widely applied in water requirements estimate and proved *** on natural characters of Pihe River,minimum and optimum water requirement of aquatic habitat for the river maintenance were *** water requirement of Pihe River was computed too,which is related with the width of water surface,the river length and evaporation depth. Considering the water quality goal,diluting pollutant water requirement was taken into *** the EIFR of the river of 1.1.month were ultimateS,*** them,that was {1..64m/s and the minimum eco-environmental water requirement of the river was {1..84m/s.

关键词： Eco-environmental water requirements Water resource allocation Water quality goal Pollutant dilute water requirement