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chinese Science Bulletin 1997年第11期42卷 947-952页

作者： ZHANG Xiaofeng, FENG Meifu, WU Caihong and ZHOU Pei’aiState Key Laboratory of Biomembrane and Membrane Biotechnology, chinese academy of sciences. beijing 100080, china 1 . In-stitute of Zoology, chinese academy of sciences. beijing 100080, china 2 College of Life sciences. Peking University, beijing 100871, china State Key Laboratory of Biomembrane and Membrane Biotechnology Chinese Academy of Sciences Beijing 100080 China

GRANULOCYTE-MACROPHAGE colony-stimulating factor(GM-CSF),a member in the family ofglycoprotein cytokines,can not only act to stimulate proliferation of immature progenitors,butalso enhance differentiated functions of mature effector *** has two kinds of biologicaleffects on mature effector cells,*** effect and indirect *** latter is also

关键词： K+ channel patch clamp GM-CSF macrophage.

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science china(Technological sciences. 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2,REN WeiJia1,WANG ShiDa1 & WENG LiJun3 1 academy of Opto-Electronics,chinese academy of sciences.beijing 100190,china 2 Graduate University of chinese academy of sciences.beijing 100049,china 3 Lanzhou Institute of Chemical Physics,chinese academy 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

Modeling diameter distribution of the broadleaved-Korean pine mixed forest on Changbai Mountains of china

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Science china(Technological sciences. 2006年第z1期49卷 177-188页

作者： WANG Shunzhong, DAI Limin, LIU Guohua, YUAN Jianqiong, ZHANG Hengmin & WANG Qingli Institute of Applied Ecology, chinese academy of sciences. Shenyang 110016, china Graduate University of chinese academy of sciences. beijing 100039, china State Key Lab of Systems Ecology, Research Center for Eco-Environmental sciences. chinese academy of sciences. beijing 100085, china Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate University of chinese academy of sciences Beijing 100039 China State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The broadleaved-Korean pine mixed forest is a native vegetation in the Changbai Mountains, northeast china. The probability density functions including the normal, negative exponential, Weibull and finite mixture distribution, were used to describe the diameter distributions of the species groups and entire forest stand. There is a strong correlation between parameters and mean DBH except the shape parameters in the mixture distribution. The diameter classes of species and entire forest stand showed not negative exponential but normal and "S" distribution. The mixture function was better than normal and Weibull to describe the model distribution. The location parameter had an effect on the estimated frequency in the first diameter class, when the estimated location parameter was bigger than the lower limit of the first diameter class.

关键词： broadleaved-Korean pine mixed forest, diameter distribution, finite mixture distribution.

Daily variation of carbon flux in soils of Populus euphratica forests in the middle and lower reaches of the Tarim River

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Progress in Natural Science:Materials International 2007年第5期17卷 584-590页

作者： Huang Xiang , Chen Yaning , Li Weihong , Ma Jianxin and Chen Yapeng (Xinjiang Institute of Ecology and Geography, chinese academy of sciences. Urumqi 830011, china Graduate University, chinese academy of sciences. beijing 100039, china) [a]Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China [b]chinese academy of sciences Graduate University Beijing China

In order to lucubrate the daily variation of respiration in soils of Populus euphratica forests and analyze its relationship with environmental factors in the middle and lower reaches of the Tarim River, the LI-8100 instrument of soil CO2 flux system was used to measure the parameters of soil carbon flux and air temperature 10 cm above ground surface along the profiles of Usyman, Archy River, Yengisu and Karday, and the relationships between the soil carbon flux and the soil moisture content were analyzed. The nonlinear regression analysis was carried out with the software SPSS13.0. We observed that: (1) soil respiration began to be restrained when the air temperature was up to 30℃10 cm above the ground surface; (2) the rates of soil respiration under the forests of Populus euphratica were significantly different at various moisture contents, the soil carbon flux was high along the Usyman profile, which has a high soil moisture content, and it was low along the profiles of Archy River, Yengisu and Karday, which has a low soil moisture content; (3) the exponential model can be used to explain the relationship between soil respiration and air temperature 10 cm above the ground surface. The average Q10 values along the profiles of Usyman, Archy River, Yengisu and Karday are 0. 61, 0.16, 0. 22 and 0. 35 respectively, much lower than the average of the world; (4) there is a positive correlation between the soil carbon flux and the soil moisture content.

关键词： Populus euphratica soil carbon flux air temperature 10 cm above ground surface soil moisture content the Tarim River.

An improved imaging algorithm for fixed-receiver bistatic SAR

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Science china(Information sciences. 2010年第7期53卷 1461-1469页

作者： GENG XuPu1,2,3, HU YingHui1,2, YAN HongHui2 & WANG YanFei2 1Graduate School of the chinese academy of sciences. beijing 100039, china 2Institute of Electronics, chinese academy of sciences. beijing 100190, china 3beijing Institute of Environment Features, beijing 100854, china 1. Graduate School of the chinese academy of sciences Beijing 100039 China2. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China3. Beijing Institute of Environment Features Beijing 100854 China

Based on the signal model of fixed-receiver bistatic SAR, this paper analyzes the characteristics of azimuth-variant, which includes variation of range migration curve and variation of Doppler rate caused by different azimuth position of targets. Then, an extended nonlinear chirp scaling (NLCS) algorithm is proposed, with its flowchart and phase compensation functions being provided. Simulation results show that the algorithm is available for the characteristics of azimuth-variant of fixed-receiver bistatic SAR, and good focused radar images could be acquired.

关键词： synthetic aperture radar (SAR) bistatic SAR fixed-receiver characteristics of azimuth-variant range cell migration correction (RCMC)

Assessment of soil erosion and sediment delivery ratio using remote sensing and GIS:a case study of upstream Chaobaihe River catchment, north china

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International Journal of Sediment Research 2008年第2期23卷 167-173页

作者： Weifeng ZHOU1 and Bingfang WU2 1 Doctor candidate,Graduate School of the chinese academy of sciences.CAS),beijing 100039,china 2 Prof.,Institute of Remote Sensing Applications,chinese academy of sciences.CAS),beijing 100101,china [a]Doctor candidate Graduate School of the chinese academy of sciences.CAS) beijing 100039 china [b]Prof. Institute of Remote Sensing Applications chinese academy of sciences.CAS) beijing 100101 china

Soil erosion in catchment areas reduces soil productivity and causes a loss of reservoir *** parametric models have been developed to predict soil erosion at drainage basins,hill slopes and field *** well-known Universal Soil Loss Equation(USLE) represents a standardized *** reservoir,which sits on Chaobaihe River,is the main surface source of drinking water for beijing,the capital of *** and soil loss are the main reasons for sediment to enter a *** yield is assessed using a version of the universal soil loss equation modified by chinese *** year 2001 and 2002 data for factors in the equation are obtained from remote sensing or collected to form an analysis *** factors are computed and mapped using Geographic Information System *** on the complex database,the modified model is *** pixel-based computing the sediment yield per hydrological unit is *** model does not consider sediment deposition occurring on *** soil loss is often higher than the sum of those measured at catchment *** sediment delivery ratio(SDR) per hydrological unit is also *** study analyzes the main contributions of sediment yields on sub-basins of the Chaobaihe River to the Miyun Reservoir,and discusses the possible reasons for the difference between SDRs in 2001 and 2002 at different *** result shows that in the upper basin of the Miyun Reservoir,in 2001 the area of erosion that could be neglected was 8,202.76 km2,the area of low erosion 3,269.59 km2,the area of moderate erosion 3,400.97 km2,the area of high erosion 436.89 km2,the area of strong erosion 52.19 km2 and the area of severe erosion 3.13 *** highest soil loss was 70,353 t/*** in Fengning County in 2001,followed by 64,418 t/*** by Chicheng County in *** SDR in 2002 was lower than that in *** main reasons are the decreasing rainfall erosivity and total runoff.

关键词： Modified USLE Gross erosion Sediment delivery ratio

GAUSS-SEIDEL-TYPE MULTIGRID METHODS

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Journal of Computational Mathematics 2003年第4期21卷 421-434页

作者： Zhao-hui Huang Qian-shun Chang (academy of Mathematics and System sciences. chinese academy of sciences. beijing 100080, china) academy of Mathematics and System sciences Chinese Academy of Sciences Beijing 100080 China

By making use of the Gauss-Seidel-type solution method, the procedure for computing the interpolation operator of multigrid methods is simplified. This leads to a saving of computational time. Three new kinds of interpolation formulae are obtained by adopting different approximate methods, to try to enhance the accuracy of the interpolatory operator. A theoretical study proves the two-level convergence of these Gauss-Seidel-type MG methods. A series of numerical experiments is presented to evaluate the relative performance of the methods with respect to the convergence factor, CPU-time(for one V-cycle and the setup phase) and computational complexity.

关键词： Multigrid methods Gauss-Seidel solution Interpolation formula Convergence.

CONVERGENCE OF VORTEX METHODS FOR 3-D EULER EQUATIONS

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Journal of Computational Mathematics 2000年第3期18卷 239-250页

作者： Jia-fu Lin (Institute of System Science, academy of Mathematics and System sciences. chinese academy of sciences. beijing, 100080, china School of Mathematical sciences. Peking University, beijing 100871, china) 中科院系统科学所北京 100080

Presents a study on the convergence of vortex methods for the three-dimensional Euler equations in bounded domains. Related studies on the convergence of vortex methods; Formulation of vortex methods; Convergence for ... 详细信息

关键词： Euler equations vortex methods convergence initial-boundary value problem

PROBABILISTIC NUMERICAL APPROACH FOR PDE AND ITS APPLICATION IN THE VALUATION OF EUROPEAN OPTIONS

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Journal of Computational Mathematics 2001年第6期19卷 591-600页

作者： Dong-sheng Wu (Institute of Systems Science, academy of Mathematics and Systems sciences. chinese academy of sciences. beijing 100080, china ) 中科院系统科学所北京 100080

Presents a probabilistic numerical approach for a class of probabilistic differential equation. Application of the Brownian motion and Monte-Carlo method; Application in the valuation of European Options.

关键词： Brownian motion probabilistic numerical solution European Options

Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science china(Technological sciences. 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, chinese academy of sciences. beijing 100080, china 2. Graduate School of the chinese academy of sciences. beijing 100039, china 3. General Establishment of Space Science and Application, chinese academy of sciences. beijing 100080, china 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 chinese academy of sciences 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.