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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 {2. research center, Beijing 100089, china wenjianghuang @ ***)λλ Beijing agriculture information {2. research center Beijing 100089 China wenjianghuang ***

Some red edge parameters(red, Min600-72.λ, 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 Min600-72. satisfactorily.

关键词： Red edge Winter wheat Biochemistry

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,{2. Agricultural University, Beijing 100083,{2. b national engineering research center for information technology in agriculture, Beijing 100097,{2. [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

Surface electromagnetic modes contribution to the anomalous terahertz transmission through double-layered metal hole array

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Science china(information Sciences) 2012年第1期55卷 90-97页

作者： RAO Lei1&YANG DongXiao1,2.1Department of information Science and Electronic engineering,Zhejiang University,Hangzhou 31002.,{2. 2.3} center for Terahertz technology,Zhejiang University,Hangzhou 31002.,{2. 1. Department of information Science and Electronic engineering Zhejiang University Hangzhou 310027 China2. Research Center for Terahertz Technology Zhejiang University Hangzhou 310027 China

Terahertz transmission spectra through both single-layered and double-layered sub-wavelength metal hole arrays were calculated using rigorous mode-matching *** dispersion relations of the single-layered and double-layered metal hole arrays were obtained by FDTD *** are three anomalous peaks in the spectrum of the double-layered metal hole array,which arise from the three surface electromagnetic modes appearing in the dispersion *** comparing the transmission spectra and the dispersion relations of the single-layered and double-layered metal hole arrays,it was found that the two surface electromagnetic modes at higher frequencies are introduced by the single-layered metal hole array,while the one at lower frequencies is introduced by the double-layered metal hole *** validity of the analysis was qualitatively verified by the experimental *** structure can be finely designed for potential applications,such as wideband filtering.

关键词： surface electromagnetic modes double-layered metal hole array terahertz

A Novel Stable Clustering Design Method for Hierarchical Satellite Network

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Chinese Journal of Aeronautics 2010年第1期23卷 91-102页

作者： Zhou Mu,Guo Qing,Wang Zhenyong Communication research center,School of Electronics and {2. engineering,Harbin Institute of technology,Harbin 150001,china [a] Communication research center School of Electronics information engineering Harbin Institute of Technology Harbin 150001 China

This article proposes a novel stable clustering design method for hierarchical satellite network in order to increase its stability,reduce the overhead of storage and exert effective control of the delay performances based on a 5-dimensional vector model. According to the function of stability measureinent and owing to the limitation of minimal average routing table length, the hierarchical satellite network is grouped into separate stable connected clusters to improve destruction resistance and reconstruction ability in the future integrated network. In each cluster, redundant communication links with little contribution to network stability and slight influences on delay variation are deleted to satisfy the requirements for stability and connectivity by means of optimal link resources, and, also, the idea of logical weight is introduced to select the optimal satellites used to communicate with neighboring cluster satellites. Finally, the feasibility and effectiveness of the proposed method are verified by comparing it with the simulated performances of other two typical hierarchical satellite networks, double layer satellite constellation（DLSC） and satellite over satellite（SOS）.

关键词： satellite network hierarchical structure stability analysis clustering algorithms vector measurements

A single observer location method under the scatter signals position disturbance situation:the constraint total least square method

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Science china(information Sciences) 2011年第1期54卷 146-152页

作者： YANG TianChi1,YU ChaoQun2.WANG TianPeng1 & JIN Liang1 1national Digital Switching System engineering and Technological {2. center, Zhengzhou 450002.china 2.urveying and Mapping College of information engineering University, Zhengzhou 450002.china 1. national Digital Switching System engineering and Technological {2. center Zhengzhou 450002 China2. Surveying and Mapping College of Information Engineering University Zhengzhou 450002 China

A target position can be estimated using position information from scattered signals in the nonline-of-sight propagation environment in a single observer location *** is always an error in the final estimated result of the position obtained using scatter signals because measurement noise is *** reduce the total error of the system,we propose a method of converting the problem of optimizing location into a one of solving the extremes of the *** the problem of how to solve the extremes of the constraints is converted into an unconstrained problem by using the constrained total least squares(CTLS) ***,the Newton iteration method is used to obtain the optimized *** results also verify the capability of this method.

关键词： scatter position disturbing VOCTLS single observer location Newton iteration

Spray and forward:Efficient routing based on the Markov location prediction model for DTNs

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Science china(information Sciences) 2012年第2期55卷 433-440页

作者： DANG Fei1,YANG XiaoLong1,2.& LONG KePing2.1 research center for Optical Internet and Mobile {2. Networks(COIMIN),University of Electronic Science and technology of china,Chengdu 611731,china 2.School of Computer and Communications engineering,University of Science and technology Beijing,Beijing 100083,china 1. research center for Optical Internet and Mobile {2. Networks (COIMIN) University of Electronic Science and Technology of China Chengdu 611731 China2. School of Computer and Communications Engineering University of Science and Technology Beijing Beijing 100083 China

Typical delay tolerant networks(DTNs)often suffer from long and variable delays,frequent connectivity disruptions,and high bit error *** DTNs,the design of an efficient routing algorithm is one of the key *** existing methods improve the accessibility probability of the data transmission by transmitting many copies of the packet to the network,but they may cause a high network *** address the tradeoff between a successful delivery ratio and the network overhead,we propose a DTN routing algorithm based on the Markov location prediction model,called the spray and forward routing algorithm(SFR).Based on historical information of the nodes,the algorithm uses the second-order Markov forecasting mechanism to predict the location of the destination node,and then forwards the data by greedy routing,which reduces the copies of packets by spraying the packets in a particular *** contrast to a fixed mode where a successful-delivery ratio and routing overhead are contradictory,a hybrid strategy with multi-copy forwarding is able to reduce the copies of the packets efficiently and at the same time maintain an acceptable successful-delivery *** simulation results show that the proposed SFR is efficient enough to provide better network performance than the spray and wait routing algorithm,in scenarios with sparse node density and fast mobility of the nodes.

关键词： delay tolerant networks spray and forward Markov position prediction routing algorithm

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2.3, WANG Pengxin4, YANG Hua1,2.3, LIU Shaomin1,2.3 & WANG Jindi1,2.3 1. research center for Remote Sensing and GIS, School of Geography, Beijing Normal University, Beijing 100875,{2. 2. State Key Laboratory of Remote Sensing Science, Beijing 100875,{2. 3. Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, Beijing 100875,{2. 4. Department of information Management, College of information and Electronic engineering,{2. Agricultural University, Beijing 100083,{2. 1. research center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing Science Beijing 100875 China 3. Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing 100875 China 4. Department of information Management College of Information and Electronic Engineering China Agricultural University Beijing 100083 China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Distribution,formation and evolution of sand ridges on the East china Sea shelf

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Science china(Technological Sciences) 2010年第3期53卷 822-828页

作者： ZHAO RenBao 1,2.SUN HaiTao 3,WU YaSheng 3 &ZHAO ChuanFeng 1,2.1MOE Key Laboratory of Petroleum engineering,china University of Petroleum,Beijing 102.49,china 2.Enhanced Oil Recovering research center,china University of Petroleum,Beijing 102.49,china 3Faculty of Natural Resource&information technology,china University of Petroleum,Beijing 102.49,china 1. MOE Key Laboratory of Petroleum engineering China University of Petroleum Beijing 102249 China2. Enhanced Oil Recovering Research Center China University of Petroleum Beijing 102249 China3. Faculty of Natural Resource & Information Technology China University of Petroleum Beijing 102249 China

Influence of CO2.corrosion on reservoir mineralogical composition,pore structure and their mechanical characteristics was studied using XRD,SEM,rock tri-axial machine and core flow experimental *** was found that the corrosion effect was mainly attributed to rock texture and structure,fluid composition and external dynamical conditions in the experimental *** cores with bedding structures,their bedding surfaces were the preferential corrosion regions,because micro-cracks would evolve at these surfaces in the pressure-releasing ***,for cores with massive structures controlled by stable water environment,the CO2.corrosion would result in pore enlargement and secondary pore *** gas velocity from outlet showed sharp increase in the injection process of CO2.H2. *** could be explained by two changes caused by *** was the opening and closure of *** other was particle *** the corrosion time increased,both tensile strength and compressive strength decreased,which confirmed decrease of cementation *** should also be noted that permeability increase and micro-cracks generation would pose damage to the capacity of CO2.geological storage.

关键词： carbon dioxide geological storage mineralization enhanced oil recovery corrosion

2.5-dimensional angle potential field algorithm for the real-time autonomous navigation of outdoor mobile robots

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Science china(information Sciences) 2011年第10期54卷 2100-2112页

作者： QIU Quan 1,3 & HAN JianDa 2.1 Beijing research center of Intelligent Equipment for {2.,Beijing 100097,china 2.State Key Laboratory of Robotics,Shenyang Institute of Automation,Chinese Academy of Sciences,Shenyang 110016,china 3 national research center for Intelligent Agricultural Equipment,Beijing 100097,china 1. Beijing research center of Intelligent Equipment for {2. Beijing 100097 China3. National Research Center for Intelligent Agricultural Equipment Beijing 100097 China2. State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China

A new real-time algorithm for the autonomous navigation of mobile robots equipped with laser scanners is proposed in this *** from the existing algorithms designed for 2.dimensional navigation problems,the new algorithm introduces the height information of the obstacles into the guidance process and behaves as a 2.5-dimensional angle potential field algorithm (2.5D-APF) to fulfill the navigation requirements under complex outdoor terrain ***,one laser scan is partitioned into two kinds of function sectors: guidance sector and inspecting ***,the guidance sector and the inspecting sectors are reconstructed to form a virtual guidance scan,where the 2.5D information is taken into ***,the conventional APF is improved to analyze the virtual guidance scan and generate the navigation *** new algorithm is tested on a tracked mobile robot,and the experimental results validate the proposed algorithm.

关键词： robot 2.5-dimensional outdoor real-time autonomous navigation