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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,china 2.institute of surveying and mapping,Information Engineering University of the Chinese People’s Liberation Army,zhengzhou 450052.china Chinese Academy of Sciences Institute of Geographical Sciences and Natural Resources Beijing China Information Engineering University of the Chinese People’s Liberation Army Institute of Surveying and Mapping 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.

Experimental Research on Shear Behavior of Reinforced Concrete Composite Beams Under Uniformly Distributed Load

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china Ocean Engineering 1998年第4期13卷 467-476页

作者： ZHAO Shunbo Ass. Prof., North china institute of Water Conservancy and Hydroelectric Power, zhengzhou 450045, P. R. china. N. china Inst. Water Conserv./H.P. Zhengzhou 450045 China

An experimental program was carried out to study the shear behavior of the reinforced concrete composite beam (RCCB) subjected to two-phase uniformly distributed load. A total of 12 reinforced concrete composite beams were tested: 10 of them were the RCCB subjected to two-phase uniformly distributed load, the other 2 were the comparative reinforced concrete beams cast at the same time as the RCCB subjected to one-phase uniformly distributed load. The interface of precast unit and recast concrete was natural and rough. The test range of the main composite factors: the ratio of precast section depth to composite section depth was from 0.35 to 0.65, the ratio of first-phase load moment to precast section ultimate bearing moment was from 0.25 to 0.65. Based on the test results, the stresses of the longitudinal reinforcements and stirrups, the load-bearing properties of the interface, the crack state and the failure characteristics of the RCCB under uniformly distributed load are discussed. The effects of the stirrups, the concrete strength and the composite factors on the shear resistance of the RCCB are analyzed, and the method for evaluating the shear resistance of the RCCB is proposed.

关键词： reinforced concrete composite beam shear resistance composite factor mechanism of failure

Rapid Water-Sky-Line Detecting Algorithm in Marine Celestial Navigation

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Rapid Water-Sky-Line Detecting Algorithm in Marine Celestial...

Weighted estimates for the multilinear singular integral operators with non-smooth kernels

第三届中国卫星导航学术年会

作者： Chonghui Li, Yong Zheng, Yulei Yuan, Yufei Yang zhengzhou institue of surveying and mapping, HeNan, china, 450052

The determination of plumb line is one of the difficulties in marine ce- lestial navigation, and image process is usually used to resolve it. Existing algorithms such as Wavelet transform and Sobel operator have many disadvantages, the former is difficult to realize, and the later is time-consuming. In order to solve these problems, a rapid Water-Sky-Line detecting algorithm was proposed, which includes such steps as resample, automatic threshold segmentation, Vector operator edge detecting, and Hough transform. Especially, the time-consuming of Vector operator is about 1/4 of existing algorithm such as Sobel operator. At last, all the steps were realized by VC++6.0, and then the idiographic image coordinate of Water-Sky-Line is extracted rapidly and accurately.

关键词： Water-Sky-Line resample threshold segmentation vector operator Hough transform

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Science china Mathematics 2011年第3期54卷 587-602页

作者： HU GuoEn1 & LU ShanZhen2 1Department of Applied Mathematics, zhengzhou Information Science and Technology institute, zhengzhou 450002, china 2Department of Mathematics, Beijing Normal University, Beijing 100875, china Department of Applied Mathematics Zhengzhou Information Science and Technology Institute Department of Mathematics Beijing Normal University

In this paper, by sharp function estimates and certain weak type endpoint estimates, the authors establish some weighted norm inequalities with Ap weights for the multilinear singular integral operators with non-smoot... 详细信息

关键词： approximation to the identity weighted norm inequality singular integral operator non-smooth kernel Calderón-Zygmund decomposition

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DCS结构的面粉生产监控系统

计算机工程与应用 2004年第7期40卷 230-231页

作者：祝玉华甄彤郑州工程学院计算机系

介绍了一种分散控制集中监视的面粉厂DCS系统。该系统由PC机、工控机、PLC组成,能对生产过程进行自动控制,并通过网络把生产情况传送到各地方。文章对系统的软、硬件设计作了详细介绍。

关键词： DCS系统 PLC 监控系统面粉生产线

Modification ratio estimation for a category of adaptive steganography

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Science china(Information Sciences) 2010年第12期53卷 2472-2484页

作者： LUO XiangYang 1 , LIU FenLin 1 , YANG ChunFang 1 & LIAN ShiGuo 2 1 zhengzhou Information Science and Technology institute, zhengzhou 450002, china 2 France Telecom R&D Beijing, Beijing 100080, china zhengzhou Information Science and Technology institute France Telecom R&D Beijing

This paper investigates the detection of adaptive image steganography. Firstly, the sample pair analysis model of multiple least-significant bits (MLSB) replacement is analyzed, and the conditions under which the adaptive steganography can be detected via this model are given. For the category of adaptive steganography satisfying these conditions, a general quantitative steganalysis method is presented based on specific areas and sample pair analysis. Then, for a typical adaptive steganography, some concrete methods are proposed to select specific areas and trace sets of sample pairs, and estimate the stego modification ratios. Experimental results show that the proposed methods can estimate the stego modification ratio accurately. This verifies the validity of the proposed general quantitative steganalysis method.

关键词： adaptive steganography steganalysis MLSB (multiple least significant bits) sample pair analysis modification ratio

SYNTHESIS　AND　CHARACTERIZATION　OF　NEIV　PICKET　FENCE　CROWN－PORPHYRIN　AND　ITS　Zn（Ⅱ），Fe（Ⅲ）　COMIPLEXES

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Chinese Chemical Letters 1996年第4期7卷 325-328页

作者： Yang de WU,Fa Cheng QIAN, Lian Fang SHENa(Department of Chemistry, zhengzhou University. zhengzhou 450052.b(zhengzhou Tobacco Research institute of china National Tabacco Coorporation.zhengzhou 450000)c(Laboratory of Magnetic Resonance and Atomic and Mole

A new picket fence porphyrin appended with multiple benzo -15-crown -5 ueits was synthesized by the reaction of meso- α,α,α,α- tetra (2-aminophenyl)porphyrin and 4- chloroformylbenzo - 15- crow - 5. Its Fe(Ⅲ) and... 详细信息

关键词： Zn COMIPLEXES CROWN PORPHYRIN FENCE CHARACTERIZATION OF Fe AND ITS

SURFACE STATE AND CATALYTIC ACTIVITY OF ACTIVATED AMORPHOUS Fe_(80)Zr_(12)B_8 ALLOY

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Acta Metallurgica Sinica(English Letters) 1993年第7期6卷 57-63页

作者： WANG Xike SHEN Ningfu CHEN Haisong zhengzhou institute of Technology,zhengzhou,chinaZHANG Haifeng Luoyang Research institute for Ship Materials,Luoyang,chinaGU Haicheng Xi’an Jiaotong University,Xi’an,china Professor,Research Centre for Materials,zhengzhou institute of Technology,zhengzhou 450002,china

The depth profile of composition,chemical state of elements and morphology of as- received and activated amorphous Fe_(80)Zr_(12)B_8 alloy ribbons have been studied by means of Auger electron spectroscopy,X-ray photoelectron spectroscopy and scanning Auger microprobe combined with Ar ion *** dull and free sides of the as- received ribbons were covered with an iron oxide *** a pronounced surface segregation and oxidation of B and precipitation of microcrystalline α-Fe particles were observed on both sides of activated ribbons,B and Zr were oxidized selectively in subsurface *** both sides of ribbons,a porous surface structure formed. The BET surface area was measured to be increasing from 0.11 to 2.68 m^2/*** principal mechanism of in situ activation has been discussed.

关键词： amorphous Fe_(80)Zr_(12)B8 alloy surface state catalytic activity in situactivation

Friction Wear Property of Brake Materials by Copper-based Powder Metallurgy With Various Brake Speeds

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材料热处理学报 2004年第5期25卷 126-129页

作者： LIUJian-xiu GAOHong-xia WEIXiu-lan zhengzhouUniversityofLightIndustry. MechanicalEngineeringInstituteZhengzhouChina

The experiment is conducted on MM-1000 friction test machine, which tests friction wear property of copper-based brake materials by powder metallurgy at different brake speeds. It shows that the coefficient of friction and wear volume are greatly influenced by brake speed. When the brake speed is 4000 r/min, which is a bit higher, the material still has a higher coefficient of friction with 0.47. When the brake speed is over 4000r/min, the coefficient of friction decreased rapidly. When the brake speed is 3000r/min, the material’s wear is in its minimum. That is to say no matter how higher or lower the brake speed is the wear volume is bigger relatively. With the brake speed of the lower one it mainly refers to fatigue wear; while of higher one it mainly refers to abradant and oxidation wear.

关键词：粉末冶金刹车铜材料磨损