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Polynomial analysis of canopy spectra and biochemical component content inversion

Science china Earth Sciences 2005年第10期48卷 1780-1791页

作者： YAN Chunyan1, LIU Qiang1, NIU Zheng1, WANG Jihua2, HUANG Wenjiang2 & LIU Liangyun 2 1. 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 2. National engineering research center for information technology in agriculture, Beijing 100089, 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 china National engineering research center for information technology in agriculture Beijing china

A polynomial expression model was developed in this paper to describe directional canopy spectra, and the decomposition of the polynomial expression was used as a tool for re-trieving biochemical component content from canopy multi-angle spectra. First, the basic formula of the polynomial expression was introduced and the physical meaning of its terms and coeffi-cients was discussed. Based on this analysis, a complete polynomial expression model and its decomposition method were given. By decomposing the canopy spectra simulated with SAILH model, it shows that the polynomial expression can not only fit well the canopy spectra, but also show the contribution of every order scattering to the whole reflectance. Taking the first scattering coefficients a10 and a01 for example, the test results show that the polynomial coefficients reflect very well the hot spot phenomenon and the effects of viewing angles, LAI and leaf inclination angle on canopy spectra. By coupling the polynomial expression with leaf model PROSPECT, a canopy biochemical component content inversion model was given. In the simulated test, the canopy multi-angle spectra were simulated by two different models, SAILH and 4-SCALE re-spectively, then the biochemical component content was retrieved by inverting the coupled polynomial expression + PROSPECT model. Results of the simulated test are promising, and when applying the algorithm to measured corn canopy multi-angle spectra, we also get relatively accurate chlorophyll content. It shows that the polynomial analysis provides a new method to get biochemical component content independent of any specific canopy model.

关键词： polynomial expression, canopy spectra, decomposition, biochemical component content, inversion.

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research progress on electrical signals in higher plants

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Progress in Natural Science:Materials International 2009年第5期19卷 531-541页

作者： Xiaofei Yana, Zhongyi Wang a, Lan Huang a, Cheng Wang b, Ruifeng Hou b, Zhilong Xu b, Xiaojun Qiao b a College of information and Electrical engineering, china Agricultural University, Beijing 100083, china b National engineering research center for information technology in agriculture, Beijing 100097, china [a]College of information and Electrical engineering China Agricultural University Beijing 100083 China [b]National Engineering Research Center for Information Technology in Agriculture Beijing 100097 China

This review introduces the characteristics of electrical signals in higher plants and their corresponding physiological significance, and describes in detail the impact of environmental factors (e.g. light and temperature) on the electrical potential of the plants. Also, we evaluate the measurement techniques used for electrical signals in plants, including intracellular measurement, extracellular measurement, measurement of the ion channel based on the patch-clamp technique and on the non-invasive microelectrode vibrating probe technique. We also give a brief review of the applications of these methods for investigating electrical signals in plants. The ionic mechanism of electrical activity in plants is then discussed in terms of environmental response in higher plants, and this is used to provide a theoretical basis for quantitative description of the electrical signals in plants. A model for interpretation of the electrical signal mechanisms in higher plants is discussed, but further experiments are required for the verification of this model.

关键词： Ion channel Temperature-induced Light-induced Ion mechanism Measurement technology

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Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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Science china(Technological Sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2, HUANG GuanHua1,2 & QU ZhongYi3 1 center for agriculture Water research, china Agricultural University, Beijing 100083, china 2 Chinese-Israeli International center for research and Training in agriculture, china Agricultural University, Beijing 100083, china 3 Water Conservancy and Civil engineering College, Inner Mongolia Agricultural University, Hohhot 010018, china 1. center for agriculture Water research China Agricultural University Beijing 100083 China 2. Chinese-Israeli International center for research and Training in agriculture China Agricultural University Beijing 100083 China 3. Water Conservancy and Civil engineering College Inner Mongolia Agricultural University Hohhot 010018 China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

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The Red Edge Parameters Diversification Disciplinarian and Their Application in Winter Wheat

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计算机工程 2002年第S1期28卷 154-159页

作者： HUANG Wenjiang, WANG Jihua, ZHAO Chunjiang, WANG Zhijie (Beijing agriculture information technology research center, Beijing 100089, china wenjianghuang @ ***)λλ Beijing agriculture information technology research center Beijing 100089 China wenjianghuang ***

Some red edge parameters(red, Min600-720λ, dredλ, dminλλ, dred / dmin∑λ, d680-750λ, andnir) and the relationship between these parameters and the parameters of biochemistry and biophysics of winter wheat were studied by regression analysis. The results indicated that there existed some changes in these red edge parameters in the whole growth stages, and there were strong correlations between red edge parameters and parameters of biochemistry and biophysics. Thus, the red λedge parameters were found valuable for assessment of wheat parameters of biochemistry and biophysics. Thered can be used to λestimate the soluble sugar content and the chlorophyll content. The dred was the best estimator of total nitrogen content. LAI can λbe estimated by Min600-720 satisfactorily.

关键词： Red edge Winter wheat Biochemistry

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ON-DEMAND GEO-COMPUTING: AN EASY WAY FOR AGRICULTURAL APPLICATION OF GEO-COMPUTING

ON-DEMAND GEO-COMPUTING: AN EASY WAY FOR AGRICULTURAL APPLIC...

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第四届智能化农业信息技术国际学术会议

作者： Jian Wang Chunjiang Zhao National engineering research center for information technology in agriculture 100097 Beijing china

＜正＞By discussing Grid GIS,UbiGIS and OpenGIS, and analyzing the challenges that current geo- computing facing,the paper concludes that geo- computing should be more suitable for common people to understand and *** and supported by on demand computing,the paper presents a geo-computing strategy termed on-demand geo-computing （ODGC）.Comparing with Grid GIS,UbiGIS and OpenGIS,the paper suggests that ODGC focus on the strategy that provides users with geo-computing capabilities on their *** paper breaks the on-demand feature into suitability, temporal-validity and easy-to-use features,and develops a conceptual model termed geo-VO to achieve these ***-VO is the fusion of virtual organization,information supply chain and geospatial information value-add ***-VO functions as both geo-computing domain reference model and coordinative computing model of distributed geo-computing ***-task-VO is another conceptual model that describes how ODGC *** paper discusses ODGC philosophy by geo-VO and geo-task-VO and the ingredients that enable the agileness,easy-to-use and on-demand *** illustrate and provide an intuitive picture of ODGC,an example termed geographical cartography service is developed to explain how an ODGC application and service is developed and *** the end,the paper concludes ODGC and suggests the future studies.

关键词： Geo-computing On demand computing Grid computing Grid GIS Ubiquitous computing UbiGIS Web services

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INTELLIGENT CONTINUOUS HUMIDITY GENERATOR WITH SATURATED SALT SOLUTIONS

INTELLIGENT CONTINUOUS HUMIDITY GENERATOR WITH SATURATED SAL...

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The 3rd International Symposium on Intelligent information technology in agriculture(ISIITA)

作者： Yunhe Zhang Xiaojun Qiao Chunyan Jiao National engineering research center for information technology in agriculture Beijing 100089 china

＜正＞Based on the principle that air’s relative humidity above saturated salt solution in balance state is function of temperature,automatic control of temperature has been realized after summarizing and absorbing the research findings at home and *** this paper,we studied humidity generator that can generate continuous humidity value,which makes the calibration for humidity sensors and other pocket humidity meters more *** research on this type of humidity generator is pioneer in china and has significant research value and practicality.

关键词： humidity generator based on saturated salt semiconductor temperature controller single chip

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

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

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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 1College of information engineering Capital Normal University Beijing 100037 china 2.ational engineering research center for information technology in agriculture Beijing 100097 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 Beijing 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

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The Red Edge Parameters of Different Wheat Varieties Under Different Fertilization and Irrigation Treatments

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Agricultural Sciences in china 2002年第7期1卷 745-751页

作者： ZHAO Chun-Jiang, HUANG Wen-Jiang, WANG Ji-hua, YANG Min-hua and XUE Xu-zhang( National engineering center for information technology in agriculture , Beijing 100089 , P. R . china) National engineering center for information technology in agriculture Beijing 100089 P.R. China

The dynamics of red edge parameters at different growth stages of wheat canopy was studied. The red edge position moved to the longer wavelength from erecting stage to heading stage, and returned to the original wavelength direction from grain-filling stage to maturity stage. The leaf total nitrogen content (LTN) is positively related to red edge amplitude (d λ red) and NIR platform amplitude (d λNIRP) and the correlation coefficient improved as growth stage extended. The chlorophyll content (TChl) is negatively related to d λ red from erecting stage to the elongation stage, and positively related to d λ red from heading stage to milky maturity stage. TChl is also positively related to d λNIRP. The leaf area index (LAI) is positively related to d λ red and d λNIRP, and the correlation coefficient improved as growth stage extended. It was concluded that d λ red and d λNIRP can be used as the indicators of winter wheat growth state, and guide the fertilization and irrigation decision making. The λNIRF is suitable for derivation of LTN, the d λ red for TChl, and the d λ red or d λNIRP for LAI.

关键词： Winter wheat Spectrum Red edge parameters (REP) Variety Fertilizer Water

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ANN-BASED WHEAT CHLOROPHYLL DENSITY ESTIMATION USING CANOPY HYPERSPECTRAL VEGETATION INDICES

ANN-BASED WHEAT CHLOROPHYLL DENSITY ESTIMATION USING CANOPY ...

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亚洲精细农业与计算机农业应用联合大会

作者： Wang Dacheng 1 2 Wang Jihua 2 Li Cunjun 2 Zhang Dongyan 1 2 Huang Jingfeng 1 1 Institute of Agricultural Remote Sensing and information technology Zhejiang University 310029 china 2 National engineering research center for information technology in agriculture Beijing 100097 china

Canopy leaf Chlorophyll Density is a key index for evaluating crop potential photosynthetic efficiency and nutritional stress. Leaf Chlorophyll Density estimate using canopy hyperspectral vegetation indices provides a rapid and non-destructive method to evaluate yield predictions. A systematic comparison of two approaches to estimate Chlorophyll Density using 6 spectral vegetation indices （VIs） was presented in this study. In this study ,the traditional statistical method based on power regression analyses was compared to the emerging computationally powerful techniques based on artificial neural network （ANN）. The regression models of TCARI 、SAVI 、MSAVI and RDVIgreen were found to be more suitable for predicting Chlorophyll Density when only traditional statistical method was used,especially TCARI and RDVI. ANN method was more appropriate to develop prediction models. The comparisons between these two methods were based on analysis of the statistic parameters. Results obtained using Root Mean Square Error （RMSE） for ANNs were significantly lower than the traditional method. Especially for TCARI,T values performed 57.32% ,successed in using Back-Propagation Network （BPN）. From this analysis,it is concluded that the neural network is more robust to train and estimate crop Chlorophyll Density from remote sensing data.

关键词： wheat hyperspectral vegetation index Chlorophyll Density artificial neural network mathematical power regression

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research ON FOREST FIRE PREVENTION DECISION-MAKING PLATFORM BASED ON 3S INTEGRATED technology

RESEARCH ON FOREST FIRE PREVENTION DECISION-MAKING PLATFORM ...

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第四届智能化农业信息技术国际学术会议

作者： Yuansheng Wang~(1 2) Chunjiang Zhao~(*1 2) Jing Dong~(1 2) miao Gao~(1 2) Xingyao Hao~(1 2) Zhenkun Tian~3 1 china National engineering research center for information technology in agriculture 2 Key Laboratory for information Technologies in agriculture the Ministry of agriculture 3 china Institute of Industrial Relations

＜正＞Forest fire prevention plays an important role in forest resources *** the network environment,it is an important approach to improve the efficiency of forest fire prevention with the application of geographic information system（GIS）, global positioning system（GPS ）,remote sensing technology（RS）and their *** paper put in order the information resources for many years in Fangshan District in Beijing and established a spatial database including airscapes,remote sensing images, forest sub-compartment data,***, based on the computer language JAVA,a distributed calculating platform integrated with the 3S technologies was *** platform can not only realize the functions of forecasting forest fire danger grade,locating fire site,forecasting fire behavior,position service,commanding fire fighting and loss evaluation,but also provide the information management methods and decision -support services for forest fire archives management,fire information publishing,forest fire suppression for Fangshan Forest Bureau.

关键词： 3S integrated technology Java forest fire prevention position service policymaking support

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