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Assessing Reclamation Levels of Coastal Saline Lands with Integrated Stepwise Discriminant Analysis and Laboratory Hyperspectral Data

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Pedosphere 2006年第2期16卷 154-160页

作者： SHI Zhou CHENG Jie-Liang HUANG Ming-Xiang ZHOU Lian-Qing institute of Agricultural remote {2. and information system Zhejiang University Hangzhou 310029 （China）. State Key Laboratory of remote sensing Science Institute of Remote Sensing Application Chinese Academy of Sciences Beijing 100101 （China）

At different times over the past 30 years in Zhejiang Province, china, the coastal tidelands have been successively enclosed and reclaimed for agricultural land use. The purpose of this work was to evaluate whether laboratory hyperspectral data might be used to estimate the physicochemical characteristics of these reclaimed saline soils. A coastal region of Shangyu City (Zhejiang Province), which was grouped into four subzones according to reclamation history, was used as the study area, and soil samples were collected in each subzone. Physicochemical analyses showed that the soils were characterized by high electrical conductivity and sand content with low organic matter; the longer the saline lands had been reclaimed, the lower were the electrical conductivity and sand content and the higher the organic matter content. These changing trends of soil chemical and physical properties were found in laboratory reflectance spectra of soil samples and their first-order derivative curves. Stepwise discriminant analysis (SDA) identified six salient spectral bands at 488, 530, 670, 880, 1400, and 1900 nm. Using derived discriminant functions for saline lands with different historical years of reclamation, classification revealed an overall accuracy from a self-test of 86.6% and from cross-validation of 89.3%. Therefore, as opposed to time-consuming field investigations, this study suggested that remotely sensed hyperspectral data could serve as a promising measure to assess the reclamation levels of coastal saline lands.

关键词： hyperspectra reclamation remote sensing saline soil SDA

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The retrieval of two-dimensional distribution of the earth's surface aerodynamic roughness using SAR image and TM thermal infrared image

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Science china Earth Sciences 2004年第12期47卷 1134-1146页

作者： ZHANG Renhua 1 ,WANG Jinfeng 1 ,ZHU Caiying 1,2.,SUN Xiaomin 1 & ZHU Zhilin 1 1.institute of geographical Sciences and Natural Resources,Chinese Academy of Sciences,Beijing 100101,{2. 2.institute of Surveying and Mapping,information Engineering university of the Chinese People’s Liberation Army,Zhengzhou 450052.{2. 1. Chinese Academy of Sciences Institute of Geographical Sciences and Natural Resources 100101 Beijing China 2. information Engineering university of the Chinese People’s Liberation Army Institute of Surveying and Mapping 450052 Zhengzhou China

After having analyzed the requirement on the aerodynamic earth’s surface rough- ness in two-dimensional distribution in the research field of interaction between land surface and atmosphere, this paper presents a new way to calculate the aerodynamic roughness using the earth’s surface geometric roughness retrieved from SAR (Synthetic Aperture Radar) and TM thermal infrared image data. On the one hand, the SPM (Small Perturbation Model) was used as a theoretical SAR backscattering model to describe the relationship between the SAR back- scattering coefficient and the earth’s surface geometric roughness and its dielectric constant re- trieved from the physical model between the soil thermal inertia and the soil surface moisture with the simultaneous TM thermal infrared image data and the ground microclimate data. On the basis of the SAR image matching with the TM image, the non-volume scattering surface geo- metric information was obtained from the SPM model at the TM image pixel scale, and the ground pixel surface’s equivalent geometric roughness—height standard RMS (Root Mean Square) was achieved from the geometric information by the transformation of the typical to- pographic factors. The vegetation (wheat, tree) height retrieved from spectrum model was also transferred into its equivalent geometric roughness. A completely two-dimensional distribution map of the equivalent geometric roughness over the experimental area was produced by the data mosaic technique. On the other hand, according to the atmospheric eddy currents theory, the aerodynamic surface roughness was iterated out with the atmosphere stability correction method using the wind and the temperature profiles data measured at several typical fields such as bare soil field and vegetation field. After having analyzed the effect of surface equivalent geo- metric roughness together with dynamic and thermodynamic factors on the aerodynamic surface roughness within the working area, this paper first establishe

关键词： surface geometric roughness, aerodynamic surface roughness, SAR backscattering model, moisture retrieval model, roughness transformation model.

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Kalman filtering for time-delayed linear systems

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Science in china(Series F) 2006年第4期49卷 461-470页

作者： LU Xiao1,2.& WANG Wei1 1. Research Center of information and Control, Dalian university of Technology, Dalian 11602., {2. 2. Shenzhen Graduate School, Harbin institute of Technology, Shenzhen 518055, {2. 1. Research Center of information and Control Dalian University of Technology Dalian 116024 China 2. Shenzhen Graduate School Harbin Institute of Technology Shenzhen 518055 China

This paper is to study the linear minimum variance estimation for discretetime systems. A simple approach to the problem is presented by developing re-organized innovation analysis for the systems with instantaneous and double time-delayed measurements. It is shown that the derived estimator involves solving three different standard Kalman filtering with the same dimension as the original system. The obtained results form the basis for solving some complicated problems such as H, fixed-lag smoothing, preview control, H, filtering and control with time delays.

关键词： discrete-time systems delayed measurements innovation analysis Riccati equations.

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Binary particle swarm optimization with multiple evolutionary strategies

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Science china(information Sciences) 2012年第11期55卷 2485-2494页

作者： ZHAO Jing1,HAN ChongZhao1 & WEI Bin2.1Ministry of Education Key Lab For Intelligent Networks and Network Security,State Key Laboratory for Manufacturing systems Engineering,institute of Integrated Automation,School of Electronics and {2. Engineering,Xi'an Jiaotong university,Xi'an 710049,china 2.1} of system Engineering,School of Electronics and {2. Engineering,Xi'an Jiaotong university,Xi'an 710049,china 1. Ministry of Education Key Lab For Intelligent Networks and Network Security State Key Laboratory for Manufacturing Systems Engineering Institute of Integrated Automation School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an 710049 China2. Institute of System Engineering School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an 710049 China

This paper introduces a novel variation of binary particle swarm optimization(BPSO) algorithm and a further extension to improve its ***,mimicking the behaviors of some creatures group,multiple evolutionary strategies BPSO(MBPSO) is introduced which takes different evolutionary strategies for various particles according to their ***,on the basis of MBPSO,a new strategy is discussed to improve the performance of the MBPSO(M2.PSO) which adopts the concept of the mutation operator aiming to overcome the premature convergence and slow convergent speed during the later stages of the *** proposed two algorithms are tested on seven benchmark functions and their results are compared with those obtained by other *** results show that our methods outperform the other algorithms.

关键词： binary particle swarm optimizer evolutionary strategies swarm intelligence

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The quantification of remote sensing

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Science china(Technological Sciences) 2005年第S2期48卷 1-11页

作者： GU Xingfa1,2.3,TIAN Guoliang1,2. LI Xiaowen1,2.& GUO Jianning4 1. State Key Laboratory of remote sensing Science, Jointly Sponsored by the {2. of remote sensing Applications of Chinese Academy of Sciences and Beijing Normal university, Beijing 100101, china 2. The Center for National Spaceborne Demonstration, Beijing 100101, china 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 4. china Center for Resource Satellite Data and Application, Beijing 100830, china Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Beijing Normal Univ State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Ctr Natl Spaceborne Demonstrat Beijing 100101 Peoples R China Inst Natl Rech Agron F-84914 Avignon France china Ctr Resource Satellite Data & Applicat Beijing 100830 Peoples R China

The paper firstly defined the remote sensing {2. quantification, analyzed the necessity of developing remote sensing quantification, figured out the application guidelines requirement, and pointed out the importance of quantification research. Then taking the remote sensing application research of CBERS-02.data quantification as the example, the paper described the whole quantification system of “remotely sensed digital signal-radiation {2.-field parameter inversion”. Finally the paper gave the prospect for the development trend of the quantitative remote sensing.

关键词： remote sensing information quantification CBERS-02 radiometric calibration surface parame- ter reversion.

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Estimation of convergence rate for multi-regression learning algorithm

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Science china(information Sciences) 2012年第3期55卷 701-713页

作者： XU ZongBen1,2. ZHANG YongQuan3,1,2.& CAO FeiLong3 1institute for information and {2. Sciences, Xi’an Jiaotong university, Xi’an 710049, china 2.OE Key Labratory for Intelligent Networks and Network Security, Xi’an Jiaotong university, Xi’an 710049, china 3Department of information and Mathematics Sciences, china Jiliang university, Hangzhou 310018, china 1. institute for information and {2. Sciences Xi’an Jiaotong University Xi’an 710049 China2. MOE Key Labratory for Intelligent Networks and Network Security Xi’an Jiaotong University Xi’an 710049 China3. Department of Information and Mathematics Sciences China Jiliang University Hangzhou 310018 China

In many applications, the pre-information on regression function is always unknown. Therefore, it is necessary to learn regression function by means of some valid tools. In this paper we investigate the regression problem in learning theory, i.e., convergence rate of regression learning algorithm with least square schemes in multi-dimensional polynomial space. Our main aim is to analyze the generalization error for multi-regression problems in learning theory. By using the famous Jackson operators in approximation theory, covering number, entropy number and relative probability inequalities, we obtain the estimates of upper and lower bounds for the convergence rate of learning algorithm. In particular, it is shown that for multi-variable smooth regression functions, the estimates are able to achieve almost optimal rate of convergence except for a logarithmic factor. Our results are significant for the research of convergence, stability and complexity of regression learning algorithm.

关键词： learning theory covering number rate of convergence entropy number

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L1/2.regularization

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Science china(information Sciences) 2010年第6期53卷 1159-1169页

作者： XU ZongBen 1 , ZHANG Hai 1,2., WANG Yao 1 , CHANG XiangYu 1 & LIANG Yong 3 1 institute of information and {2. Science, Xi'an Jiaotong university, Xi'an 710049, china 2.Department of Mathematics, Northwest university, Xi'an 710069, china 3 university of Science and Technology, Macau 999078, china 1. institute of information and {2. Science Xi’an Jiaotong University Xi’an 710049 China2. Department of Mathematics Northwest University Xi’an 710069 China3. University of Science and Technology Macau 999078 China

In this paper we propose an L1 /2.regularizer which has a nonconvex *** L 1/2.regularizer is shown to have many promising properties such as unbiasedness, sparsity and oracle properties.A reweighed iterative algorithm is proposed so that the solution of the L 1/2.regularizer can be solved through transforming it into the solution of a series of L 1 *** solution of the L 1/2.regularizer is more sparse than that of the L 1 regularizer, while solving the L 1/2.regularizer is much simpler than solving the L 0 *** experiments show that the L 1/2.regularizer is very useful and efficient, and can be taken as a representative of the Lp(0 < p < 1) regularizer.

关键词： machine learning variable selection regularizer compressed sensing

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THz-TDS signal analysis and substance identification via the conformal split

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Science china(information Sciences) 2012年第1期55卷 49-63页

作者： XIE WeiXin1,2.LI Jing1,2.PEI JiHong2.1School of Electronic Engineering,Xidian university,Xi'an 710071,china 2.ntelligent {2. institute,Shenzhen university,Shenzhen 518060,china 1. School of Electronic Engineering Xidian University Xi’an 710071 China2. Intelligent Information Institute Shenzhen University Shenzhen 518060 China

A terahertz time-domain spectroscopy(THz-TDS)imaging system can obtain high-dimensional signals with substance fingerprint *** introducing geometric algebra,a novel signal analysis approach to THz-TDS signals is developed based on an optical physical *** this approach,signals are represented with vectors in the high-dimensional real vector *** distribution properties and algebraic relationships of THz-TDS signals are *** is proved that every complex refractive index of substances relates to a unique 2.blade,the vectors corresponding to the samples of the same substance are collinear and belong to the intrinsic 2.blade of the *** decomposed through the conformal split with respect to a 2.blade,THz-TDS signals of high dimensionality can be related to vectors in a 2.dimensional *** on the conformal split properties we deduced,two criteria for substance identification on the basis of THz-TDS signals are ***,a novel substance identification method via the conformal split is *** the method,the 2.blade related to each "known" substance is calculated with two vectors corresponding to THz-TDS signals measured from samples of the substance but with dierent *** the conformal split with respect to those 2.blades,an identified vector corresponding to a THz-TDS signal is linearly related to the vector in a 2.dimensional *** substance of a sample can be identified using criteria on the projected vectors in the *** method can contribute to accurate classification and ***,two experiments are presented that show the feasibility and accuracy of this method.

关键词： terahertz time-domain spectroscopy substance identification geometric algebra conformal split

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基于WebGIS的土壤侵蚀模型的研究及应用

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水土保持学报 2001年第3期15卷 52-55页

作者：刘海涛秦其明北京大学遥感与地理信息系统研究所，北京100871

土壤侵蚀是一个世界性的环境问题 ,它使土壤的生产力和用水的质量降低 ,从而引起土壤沉积并增加了发生洪涝灾害的可能性。随着世界范围内土壤侵蚀的日益严重以及水土流失问题的突出 ,土壤侵蚀的研究越来越深入。但目前对土壤侵蚀的工作... 详细信息

土壤侵蚀是一个世界性的环境问题 ,它使土壤的生产力和用水的质量降低 ,从而引起土壤沉积并增加了发生洪涝灾害的可能性。随着世界范围内土壤侵蚀的日益严重以及水土流失问题的突出 ,土壤侵蚀的研究越来越深入。但目前对土壤侵蚀的工作大多局限在模型的改进和其相关因子的选择上 ,缺乏一个良好的用户界面来完成土壤侵蚀模型各个因子以及土壤侵蚀预测结果的分析与其可视化。通过充分利用 GIS的有关技术 ,建立了一个基于 USL E的网络土壤侵蚀模型 ,并设计了应用界面 ,解决了上述问题。试验表明 :这个基于 WEBGIS的土壤侵蚀模型 ,不仅使土壤侵蚀研究成果通过 GIS的良好界面表现出来 ,而且还可以利用 GIS的有关分析工具 ,反过来促进土壤侵蚀模型的改进。

关键词：土壤侵蚀模型 WEBGIS USLE

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An Integrated GIS/RS Approach for Soil Erosion Assessment and Modeling in Syrian Coastal Soils

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Pedosphere 2001年第2期11卷 167-174页

作者： M．AL－ABED SHIZHOU 等 GeneralOrganizationofremotesensing（Gors） P.O.Box12586Damascus（Syria） instituteofAgriculturalremote{2.andinformationsystemApplication ZhejiangUniversityHangzhou310029（China）

An integrated remote sensing (RS) and geographic {2. system (GIS) technique was employed to characterize the spatial distribution of the risk of soil erosion by water on Latakia district, Syria. The universal soil loss equation (USLE) was used to calculate the annual soil loss rates for Latakia soils. Mainly, remote sensing data, soil survey, land use inventory, elevation data and climatic atlases are used as resource data sets to generate USLE factor values. The results revealed that integration of GIS/RS with USLE was a practical and effective approach for monitoring soil erosion over large areas.

关键词： geographic information system remote sensing soil erosion universal soil loss equation (USLE)

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