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Variation properties of ionospheric eclipse factor and ionospheric influence factor

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Progress in Natural Science:Materials International 2005年第6期15卷 573-576页

作者： ZHAO Chunmei 1.2.*, YUAN Yunbin1. OU Jikun1.and CHEN Jinping3(1. Institute of Geodesy and Geophysics,{1., Wuhan 430077, china 2. Graduate School of{1., beijing 1.0039, china 3. Department of Precision Instrument and Mechanology, Tsinghua University, beijing 1.0084, china) Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Graduate School of chinese academy of sciences Beijing 100039 China Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The concepts and calculation methods of ionospheric eclipse factor (IEF) and ionospheric influence factor (IFF) are further illustrated. The temporal and spacial variation properties of IEF and IFF are studied, which shows that the properties are influenced by the geographic position and season. The possibility of improving the precision of using GPS data to determine ionospheric delay based on the above variation properties is also analysed.

关键词： GPS ionospheric eclipse factor ionospheric influence factor

A predict-correct projection method for monotone variant variational inequalities

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chinese Science Bulletin 1998年第15期43卷 1264-1267页

作者： HAN Qiaoming 1.and HE Bingsheng 2.1. Institute of Applied Mathematics,{1., beijing 1.0080,{2. 2. Department of Mathematics, Nanjing University, Nanjing 2.0093,{2. Institute of Applied Mathematics Chinese Academy of Sciences Beijing China Department of Mathematics Nanjing University Nanjing China

A predict_correct projection method is presented for solving monotone variant variational inequalities, which could exploit the advantages and overcome the difficulties of both explicit and implicit projection methods.

关键词： variant variational inequality explicit projection method implicit projection method predict_correct projection method.

Population information extraction in Chaohu watershed based on RS and GIS

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chinese Science Bulletin 2003年第2期48卷 181-183页

作者： LIU Jianjun1.2.& LI Chunlai3 1. Institute of Geochemistry,{1., Guiyang 550002. china 2. Graduate School,{1., beijing 1.0039, china 3. National Astronomical Observatories,{1., beijing 1.001.0} china Correspondence should be addressed to Liu Jianjun (e-mail: dhsliujj@ ***) Institute of Geochemistry Chinese Academy of Sciences Guiyang China Graduate School Chinese Academy of Sciences Beijing China National Astronomical Observatories Chinese Academy of Sciences Beijing China

It is always difficult to extract population in-formation of small watershed during the region environment assessment. The report adopted compound areal interpola-tion to study the population in Chaohu watershed with the GIS technique and landuse interpretation data from remote sensing. The result indicated that the method is effective to extract population information of small watershed.

关键词：巢湖流域人口分布信息提取 RS GIS 小流域生态环境评价

CH_4 uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,china

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Science china Earth {1. 2010年第7期53卷 977-983页

作者： GENG YuanBo1. LUO GuangQiang1.2.& YUAN GuoFu1.1.Institute of Geographic {1. and Natural Resources Research, chinese academy of sciences, {2. 1.01.1. china 2.Graduate University of chinese academy of sciences, {2. 1.0049, china 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The influence of near ground atmosphere CH4 concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4 uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, china. The results showed that CH4 uptake flux was positively correlated with near ground atmosphere CH4 concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4 flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.5{1.(natural conditions, 1.51.(aboveground plants were excluded), and {1.00 mg m?{1.d?1.(all plants were removed), respectively. The difference between the CH4 flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4 uptake flux is smaller than that of roots or roots-removing process. CH4 uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.36–7.86). The Leymus chinensis steppe acts as a sink for CH4, and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method

Numerical study on scanning radiation acoustic field in formations generated from a borehole

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Science china(Physics,Mechanics & Astronomy) 2005年第2期48卷 247-256页

作者： CHE Xiaohua1. ZHANG Hailan1. QIAO Wenxiao2.& JU Xiaodong2.1. Institute of Acoustics, chinese academy of sciences, beijing 1.0080,{2. 2. Faculty of Natural Resources & Information Technology, University of Petroleum, beijing 1.2.49,{2. Institute of Acoustics Chinese Academy of Sciences Beijing 100080 China Faculty of Natural Resources & Information Technology University of Petroleum Beijing 102249 China

Numerical study on scanning radiation acoustic field in formations generated by linear phased array transmitters in a fluid-filled borehole is carried out using a real axis integration (RAI) method. The main lobe width of the acoustic beams and the incident angle on the borehole wall can be controlled by means of adjusting parameters, such as the element number and the delay time between the neighboring array elements of linear phased array transmitter. The steered angle of longitudinal waves generated in the formation satisfies the Snell’s law for plane waves when the incident angle on the borehole wall is less than the first critical angle. When the lobe width of the acoustic beams is narrow and the steered angle is less than the first critical angle, the acoustic field in the formation can be approximately calculated given that the linear phased array is put in the formation without borehole. The technique of scanning radiation acoustic field can be applied to enhancing investigation resolution and signal-to-noise ratio in crosswell seismic survey and borehole acoustic reflection imaging.

关键词： formation, linear phased array transmitter, steered angle, RAI, scanning radiation.

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science china(Technological {1.) 2010年第9期53卷 2521-2527页

作者： WANG Ke1.2.REN WeiJia1.WANG ShiDa1.& WENG LiJun3 1.{1. of Opto-Electronics,chinese {1. of sciences,beijing 1.01.0,china 2.Graduate University of chinese academy of sciences,beijing 1.0049,china 3 Lanzhou Institute of Chemical Physics,chinese {1. of sciences,Lanzhou 730000,china 1. academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of china,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth {1. 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1.2.3 1. Institute of Oceanology, chinese academy of sciences, Qingdao 2.6071. china 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061. china 3. Graduate School of the chinese academy of sciences, beijing 1.0039, china 1. Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration 266061 Qingdao China 2. Institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. Graduate School of the chinese academy of sciences 100039 Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

Evaluation of the Interfacial Adhesion between Brittle Coating and Ductile Substrate by Cross-Sectional Indention

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材料热处理学报 2004年第5B期25卷 1187-1190页

作者： SUJian-yu ZHANGKun CHENGuang-nan InstituteofMechanics ChineseAcademyofSciencesBeijingChina／／GraduateSchooloftheChineseAcademyofSciencesBeijingChina InstituteofMechanics ChineseAcademyofSciencesBeijingChina

The cross-sectional indentation method is extended to evaluate the interfacial adhesion between brittle coating and ductile substrate. The experimental results on electroplated chromium coating/steel substrate show that the interfacial separation occurs due to the edge chipping of brittle coating. The corresponding models are established to elucidate interfacial separation processes. This work further highlights the advantages and potential of this novel indentation method.

关键词：分界面附着刻痕可锻衬底应力涂层铬钢

Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science china(Technological {1.) 2004年第5期47卷 518-525页

作者： L Congmin1.2. GU Yidong3, LIN Baojun3 & GUO Jiong3 1. Center for Space Science and Applied Research,{1., beijing 1.0080,{2. 2. Graduate School of the{1., beijing 1.0039,{2. 3. General Establishment of Space Science and Application,{1., beijing 1.0080,{2. Correspondence should be addressed to L Congmin 1. Center for Space Science and Applied Research Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the{1. 100039 Beijing China 3. General Establishment of Space Science and Application Chinese Academy of Sciences 100080 Beijing China

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2.m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.