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Quick image-processing method of UAV without control points data in earthquake disaster area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 523-528页

作者： LI Chang-chun1, ZHANG Guang-sheng1, LEI Tian-jie2, 3, GONG A-du2, 3 1. school of Surveying & Land Information Engineering, Henan Polytechnic university, Jiaozuo 454000, china 2. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, beijing normal university, beijing 100875. china 3. Ministry of Civil Affairs/Ministry of Education of china Academy of Disaster Reduction and Emergency Management, beijing normal university, beijing 100875. china [a] school of Surveying & Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China [b] Key Laboratory of Environmental Change and Natural Disaster Ministry of Education Beijing Normal University Beijing 100875 China [c] Ministry of Civil Affairs/Ministry of Education of china Academy of Disaster Reduction and Emergency Management Beijing Normal University Beijing 100875 China

The methods of unmanned aerial vehicles images splicing rapidly and rectifying without control points data, only using auxiliary data recorded by unmanned aerial vehicle (UAV) system, were researched. Two algorithms were proposed, including UAV images auto- splicing rapidly after image blocking and UAV images rectifying based on pseudo center points of auxiliary data. When SIFT algorithm for UAV images splicing is applied, the accuracy is very high, but the efficiency is very low. The splicing efficiency is improved greatly based on SIFT algorithm after image blocking. The results show that rectifying accuracy is very high and has no visual dislocation when pseudo center points of auxiliary data is applied.

关键词： unmanned aerial vehicles SIFT algorithm blocking quickly splicing rectification

A New Potent Inhibitor of Thrombin from the Leech Haemendipsa Yanyuanensis

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Journal of Shanghai university(English Edition) 2001年第1期5卷 86-88页

作者： ZHAO Rong le College of Life sciences, beijing normal university, beijing 100875. china College of Life sciences Beijing Normal University Beijing China

Two components of anticoagulant protein were isolated from the leech Haemendipsa yanyuanensis by heparin agarose affinity chromatography and ultracentrifugation. The determination of anticoagulant activity and characterization analysis of the protein using the method of chromogenic substrate indicates that the anticoagulant protein is thrombin specific but not factor Xa specific. The results lay a foundation for the research of the anticoagulant mechanism and application of anticoagulant protein from H. yanyuanensis.

关键词： Heamendipsa yanyuanensis anticoagulant protein thrombin factor Xa

Multiple time scale evaluation of the energy balance during the maize growing season,and a new reason for energy imbalance

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Science china Earth sciences 2009年第1期52卷 108-117页

作者： GUO JianXia1,2,BIAN LinGen3 & DAI YongJiu2 1 Meteorological Observation Center of china Meteorological Administration,beijing 100081,china 2 State Key Laboratory of Remote Sensing Science,school of Geography and Remote Sensing Science,beijing normal university,beijing 100875.china 3 Chinese Academy of Meteorological sciences,beijing 100081,china Meteorological Observation Center of china Meteorological Administration Beijing 100081 China State Key Laboratory of Remote Sensing Science School of Geography and Remote Sensing Science Beijing Normal University Beijing 100875 China

Energy imbalance is a common problem associated with the measurement of surface energy using the eddy covariance *** the evaluation of the energy balance,people usually pay more attention to the statistical result that the effective energy(the sum of sensible and latent heat) is systematically lower than the available energy(the difference of net radiation and ground heat flux).However,little attention has been paid to the existence of the reversed situation when the effective energy is larger than the available energy or their contribution to the overall energy closure *** this paper,based on the analysis of the energy balance on multiple time scales across the maize growth season,we conclude that the non-synchronization of energy components is the main reason for the existence of the reversed *** shifting the phase of the effective energy components half an hour ahead,the rates of energy closure over all time scales are improved and dramatically reduce the number of the half-hourly samples when the energy ratio exceeds 1 or is below *** to the characteristics of the energy distribution and transformation over multiple time scales,latent heat is always the main type of energy cost,and the residual of the energy balance increases with the growth of the maize plant surpassing the sensible heat for seventy *** is suggested that the heat storage and photosynthetic energy play an important role in the energy balance during the growing period of maize.

关键词： maize energy balance multiple time scale energy hysteresis

Theoretical studies on the mechanism of the thermal decarboxylation and decarbonylation of a number of α-keto-acids

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Chinese Journal of Chemistry 1995年第6期13卷 487-492页

作者： CHEN,Li-Tao CHEN,Guang-Ju FU,Xiao-YuanChemistry Department,beijing normal university,beijing 100875.china Chemistry Department Beijing Normal University Beijing 100875 China

Both processes of decarboxylation and decarbonylation of a number of acids including RCOCO2H,R=H,CH3,CH2F,CF3,CH=CH2,Ph,OH have been studied by semi-empirical MO theory AMI method to verify the reaction mechanism of each process and the effect of different substituents on *** calculated results are consistent with the experimental reports and can be summed up as follows:(1) The decarboxylation of these acids to form aldehydes and carbon dioxide is concerted and takes place through a 4-membered ring transition state in which a partial negative charge develops on the carbon of the α-carbonyl group,so that the inductive effect of some substituents is favourable for this process.(2) Their decarbonylation into carboxylic acids and carbon monoxide however is the attack of the OH on the carbon of the alkyl portion of the acid,forming a 3-membered ring transition state.(3) The activation energy of decarbonylation is lower than that of decarboxylation,since oxygen is more nucleophilic than hydrogen and also the strong OH bond need not to be broken.

关键词： Decarboxylation decarbonylation a-keto-acid

Lookback time as a test for f(R) gravity in the Palatini approach

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Research in Astronomy and Astrophysics 2011年第11期11卷 1257-1265页

作者： Zhong-Xu Zhai and Wen-Biao Liu Department of Physics, Institute of Theoretical Physics, beijing normal university, beijing 100875. china Department of Physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

We use the recently released data of lookback time (LT)-redshift relation, the cosmic microwave background shift parameter and the baryon acoustic oscillation measurements to constrain cosmological parameters of f (R) gravity in the Palatini formalism by considering the f (R) form of type (a) f (R) = R β/Rn and (b) f (R) = R + α ln R β. Under the assumption of a Friedmann-Robertson-Walker universe, we achieved the best fitting results of the free parameters (Ωm0, n) for (a) and (Ωm0, α) for (b). We find that current LT data can provide interesting and effective constraints on gravity models. Compared with other data, the LT constraints favor a smaller value of the non-relativistic matter energy density.

关键词： cosmology cosmic microwave background

ENDPOINT ESTIMATE FOR MAXIMAL COMMUTATORS WITH NON-DOUBLING MEASUES

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Acta Mathematica Scientia 2006年第2期26卷 271-280页

作者：胡国恩孟岩杨大春 Department of Applied Mathematics university of Information Engineering Zhengzhou 450002China school of mathematical sciences beijing normal university Beijing 100875China

The authors establish the weak type endpoint estimate for the maximal commutators generated by Calderon-Zygmund singular integrals and Orlicz type functions with non-doubling measures.

关键词： Maximal commutator endpoint estimate Orlicz type space non-doubling measure

Estimation of net primary productivity in china using remote sensing data

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Journal of Geographical sciences 2001年第1期11卷 14-23页

作者： SUN Rui, ZHU Qi-jiang (Dept. of Resources and Environment sciences, beijing normal university, beijing 100875. china) Dept. of Resources and Environment sciences Beijing Normal University Beijing China

It is significant to estimate terrestrial net primary productivity (NPP) accurately not only for global change research, but also for natural resources management to achieve sustainable development. Remote sensing data can describe spatial distribution of plant resources better. So, in this paper an NPP model based on remote sensing data and climate data is developed. And 1km resolution AVHRR NDVI data are used to estimate the spatial distribution and seasonal change of NPP in china. The results show that NPP estimated using remote sensing data are more close to truth. Total annual NPP in china is 2.645X109 tC. The spatial distribution of NPP in china is mainly affected by precipitation and has the trend of decreasing from southeast to northwest.

关键词： remote sensing net primary productivity vegetation model seasonal change

The minimal genus problem in rational surfaces CP^2#nCP^2

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Science china Mathematics 2006年第9期49卷 1275-1283页

作者： ZHAO Xu’an,GAO Hongzhu & QIU Huaidong LMAM,school of Mathematics Science, beijing normal university, beijing 100875. china LMAM School of Mathematics Science Beijing Normal University Beijing 100875 China

There are three key ingredients in the study of the minimal genus problem for rational surfaces CP2#nCP2: the generalized adjunction formula, the action of the orthogonal group of the Lorentz space and the geometric construction. In this paper, we prove the uniqueness of the standard form (see Definition 1.1 and Theorem 1.1) of a 2-dimensional homology class under the action of the subgroup of the Lorentz orthogonal group that is realized by the diffeomorphisms of CP2#*** the geometric construction, we determine the minimal genera of some classes (see Theorem 1.2).

关键词： rational surfaces minimal genus Lorentz orthogonal transformation

An ideal interval method of multi-objective decision-making for comprehensive assessment of water resources renewability

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Science china(Technological sciences) 2004年第z1期47卷 42-50页

作者： YANG Xiaohua1, YANG Zhifeng1,2, SHEN Zhenyao1 & LI Jianqiang3 1. school of Environment, State Key Laboratory of Water Environment Simulation, beijing normal Univer- sity, beijing 100875. china 2. school of Environment, Key Laboratory for Water and Sediment sciences of Ministry of Education, beijing normal university, beijing 100875. china 3. Water Resources and Hydropower Planning and Design General Institute, MWR, beijing 100011, china beijing normal Univ Sch Environm State Key Lab Water Environm Simulat Beijing 100875 Peoples R China beijing normal Univ Sch Environm Key Lab Water & Sediment Sci Minist Educ Beijing 100875 Peoples R China MWR Water Resources & Hydropower Planning & Design Ge Beijing 100011 Peoples R China

In order to estimate water resources renewability scientifically, an Ideal Interval Method of Multiple Objective Decision-Making (IIMMODM) is presented. This method is developed through improving an ideal point method of multiple objective decision-making. The ideal interval is obtained with assessment standard instead of ideal points. The weights are decided by using the basic point and gray code accelerating genetic algorithm. This method has synthesized the expert’s suggestion and avoided giving a mark for the objective again. It could solve the complicated problem of compatible or incompatible multi-objective assessment. The principle of IIMMODM is presented in this paper. It is used to assess the water resources renewability for nine administrative divisions in the Yellow River basin. The result shows that the water resources renewability in the Yellow River basin is very low. Compared with the gray associate analysis method, fuzzy synthesis method and genetic projection pursuit method, the IIMMODM is easier to use. Compared with the ideal point method of multiple objective decision-making, the IIMMODM has good robustness, which is applicable to the comprehensive assessments of water resources.

关键词： water resources renewability, comprehensive assessment, multiple objective decision-making,ideal interval, Yellow River basin.