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Propagation of energetic particles accelerated by the interplanetary shock in three dimensional interplanetary magnetic fields

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Propagation of energetic particles accelerated by the interp...

Synthesis of N-acetamide C_(60) nitride and its performance of optical limiting

第十四届全国日地空间物理学术研讨会

作者： Yang Wang 1 Gang Qin 1 (1 State Key Laboratory of space Weather, center for space science and applied research, chinese academy of sciences,beijing, 100190 )

As interplanetary coronal mass ejection （ICME） shock propagates from the sun to a large radial distance, it continuously accelerates particles up to many MeV. Based on a numerical solution of the Fokker-Planck transport equation, we obtained intensity and anisotropy time profiles of interplanetary shock accelerated particles propagating in the three-dimensional Parker interplanetary magnetic field. We describe the shock as a moving source of energetic particles, and treat shock acceleration process as black box. With perpendicular diffusion, the energetic particles moving in the interplanetary space can across field lines. Our simulations show that many important properties of Solar Energetic Particle（SEP） flux, including the onset time, peak time, peak intensity, decay ratio, and duration, are significantly influenced by the effect of perpendicular diffusion. By including the perpendicular diffusion, we reproduce longitudinal and latitudinal uniformity of SEP fluxes. Furthermore, we will compare our numerical results with spacecraft observations.

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chinese science Bulletin 2000年第2期45卷 150-153页

作者： TANG Guangshi, ZHU Hesun & SONG Yinglin research center of Materials science, beijing Institute of Technology, beijing 100081, china Department of applied Physics, Harbin Institute of Technology. Harbin 150001. china Department of applied Chemiscy Beiji research center of Materials science Beijing institute of Technology Beijing China Department of applied Chemistry Beijing University of Chemicals Technology Beijing China Department of applied Physics Harbin Institute of Technology Harbin China

N-acetamide C60 nitride (N-acetamide-1,2-dihydro-1,2-aza-fullerene[60]) has been synthesized by the reaction of C60 and azidoacetamide and initially characterized. Its mechanism was that the objective product is formed through intermediate triazoline. The computational study shows that N-nitride structure is thermodynamically more stable by using the semi-empirical AM1 SCF-MO method. The properties of optical limiting were tested by using double frequency Nd: YAG pulse laser system and showed that the optical limiting mechanism is reverse saturation absorption. At wavelength of 532 nm, compared with optical limiting for ns pulse, this new material has good optical limiting character for ps pulse. At wavelength of 707 nm. the capacity of optical limiting of the derivative is prior to C60-

关键词： C60 derivatives N-nitride structure optical limiting properties reverse saturation absorption.

Design and Application of an Open Structure and Network-based CCSDS Data Transmission Test-bed

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Design and Application of an Open Structure and Network-base...

Sodium fluorescence Doppler lidar to measure atmospheric temperature in the mesopause region

第一届国际测量仪器与测试自动化学术会议

作者： Yao Xiujuan Bian Chunjiang BaiXianlin Wang Chunmei (center for space science and applied research of chinese academy of sciences beijing 100080 china)

＜正＞In this paper, on the basis of introduction of CCSDS AOS （Advanced Orbiting System）, an open and network-based test-bed is presented, including its design methodology and application of data transmission in CCSDS AOS. The test-bed is built in ETX open structure with Linux OS and designed modularly. It is used for simulating, testing and validating the CCSDS AOS data transmission service and other ATE of space payloads and telecommunication system as well.

关键词： Open platform network based test-bed CCSDS.

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science Bulletin 2011年第Z1期 417-423页

作者： HU Xiong1,YAN ZhaoAi1,2,GUO ShangYong1,CHENG YongQiang1 & GONG JianCun1 1 center for space science and applied research,chinese academy of sciences,beijing 100190,china 2 Graduate University of chinese academy of sciences,beijing 100049,china

A sodium fluorescence Doppler lidar system has been developed to measure environmental parameters of the middle and upper atmosphere. The lidar system mainly comprises a transmitter system,receiver system,data acquisition and control system and data analysis system. A narrowband 589 nm laser is used to excite sodium atoms in the mesopause region. Excitation of the sodium atoms results in resonance fluorescence,which is collected by the receiver. The temperatures in the mesopause region(about 75-105 km) can be derived by analyzing the Doppler-broadened width of the sodium fluorescence. Observations were made with the lidar system,and the number density of sodium atoms and atmospheric temperature profiles were extracted from the observation data. Comparisons of the lidar temperatures and TIMED/SABER temperatures show good agreement,illustrating the reliability of the sodium fluorescence Doppler lidar measurements.

关键词： Doppler lidar sodium resonance fluorescence mesospause temperature

Improved ENSO simulation in regional coupled GCM using regressive correction method

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science china Earth sciences 2007年第8期50卷 1258-1265页

作者： FU WeiWei1 & ZHOU GuangQing2 1 Nansen-Zhu International research center (NZC), Institute of Atmospheric Physics, chinese academy of sciences (CAS), beijing 100029, china 2 State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics (LASG), Institute of At-mospheric Physics, CAS, beijing 100029, china Nansen-Zhu International research center (NZC) Institute of Atmospheric Physics Chinese Academy of Sciences (CAS) Beijing China State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics CAS Beijing China

A regressive correction method is presented with the primary goal of improving ENSO simulation in regional coupled GCM. It focuses on the correction of ocean-atmosphere exchanged fluxes. On the basis of numerical experiments and analysis, the method can be described as follows: first, driving the ocean model with heat and momentum flux computed from a long-term observation data set; the pro-duced SST is then applied to force the AGCM as its boundary condition; after that the AGCM’s simula-tion and the corresponding observation can be correlated by a linear regressive formula. Thus the re-gressive correction coefficients for the simulation with spatial and temporal variation could be obtained by linear fitting. Finally the coefficients are applied to redressing the variables used for the calculation of the exchanged air-sea flux in the coupled model when it starts integration. This method together with the anomaly coupling method is tested in a regional coupled model, which is composed of a global grid-point atmospheric general circulation model and a high-resolution tropical Pacific Ocean model. The comparison of the results shows that it is superior to the anomaly coupling both in reducing the coupled model ‘climate drift’ and in improving the ENSO simulation in the tropical Pacific Ocean.

关键词： anomaly coupling regressive correction method regional coupled model ENSO simulation

Periodic Solutions of a Model of Mitosis in Prog Eggs

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Acta Mathematicae Applicatae Sinica 2002年第4期18卷 625-628页

作者： Bei-ye Feng, Zuo-huan ZhengInstitute of applied Mathematics, academy of Mathematics and System sciences, chinese academy of sciences beijing 100080, china

In this paper,we discuss a simplified model of mitosis in frog eggs proposed by M.T. Borisuk and J.J. Tyson in [1]. By using rigorous qualitative analysis, we prove the existence of the periodic solutions on a large scale and present the space region of the periodic solutions and the parameter region coresponding to the periodic solution. We also present the space region and the parameter region where there are no periodic solutions. The results are in accordance with the numerical results in [1] up to the qualitative property.

关键词： Model of Mitosis frog eggs limit cycle

Orbit determination for geostationary satellites with the combination of transfer ranging and pseudorange data

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science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1746-1754页

作者： GUO Rui1,2,3,4,HU XiaoGong2,4,LIU Li1,WU XiaoLi1,HUANG Yong2,4 & HE Feng1 1 beijing Global Information Application and Development center,beijing 100094,china 2 Shanghai Astronomical Observatory,chinese academy of sciences,Shanghai 200030,china 3 Graduate University of chinese academy of sciences,beijing 100049,china 4 space Navigation and Positioning Technology,Laboratory of Shanghai Municipal,Shanghai 200030,china beijing Global Information Application and Development center Beijing China chinese academy of sciences Shanghai Astronomical Observatory Shanghai China (GRID:grid.9227.e) (ISNI:***) Graduate University of chinese academy of sciences Beijing China (GRID:grid.458514.9) Laboratory of Shanghai Municipal Space Navigation and Positioning Technology Shanghai China (GRID:grid.458514.9) chinese academy of sciences Shanghai Astronomical Observatory Shanghai China (GRID:grid.9227.e) (ISNI:***) Laboratory of Shanghai Municipal Space Navigation and Positioning Technology Shanghai China (GRID:grid.9227.e) beijing Global Information Application and Development center Beijing China (GRID:grid.9227.e)

Geostationary satellites(GEOs) play a significant role in the regional satellite navigation *** experiments show that the clock corrections could be mitigated through a single strategy or double differencing strategies for a navigation constellation,but for the mode of individual GEO orbit determination,high precision orbit and clock correction could not be obtained in the orbit determination based on the pseudorange data.A new GEO combined precise orbit determination(POD) strategy is studied in this paper,which combines pseudorange data and C-band transfer ranging *** strategy overcomes the deficiency of C-band transfer ranging caused by limited stations and tracking time *** the combination of transfer ranging and pseudorange data,clock corrections between the GEO and the stations can be estimated simultaneously along with orbital parameters,maintaining self-consistency between the satellite ephemeris and clock correction *** error covariance analysis is conducted to illuminate the contributions from the transfer ranging data and the psudoranging *** data collected for a chinese GEO satellite with 3 C-band transfer ranging stations and 4 L-band pseudorange tracking stations,POD experiments indicate that a meter-level accuracy is *** root-mean-square(RMS) of the post-fit C-band ranging data is about 0.203 m,and the RMS of the post-fit pseudorange is 0.408 *** component errors of the POD experiments are independently evaluated with the satellite laser ranging(SLR) data from a station in beijing,with the residual RMS of 0.076 *** SLR evaluation also suggests that for 2-h orbital predication,the predicted radial error is about 0.404 m,and the clock correction error is about 1.38 *** for the combination of one C-band transfer ranging station and 4 pseudorange stations,POD is able to achieve a reasonable accuracy with the radial error of 0.280 m and the 2-h predicted radial error of 0.888 *** syn

关键词： satellite navigation precise orbit determination pseudorange equipment ranging delay GEO SLR

Continuity in weak topology:higher order linear systems of ODE

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science china Mathematics 2008年第6期51卷 1036-1058页

作者： ZHANG MeiRong Department of Mathematical sciences,Zhou Pei-Yuan center for applied Mathematics,Tsinghua University,beijing 100084,china Department of Mathematical sciences Zhou Pei-Yuan Center for Applied Mathematics Tsinghua University Beijing China

We will introduce a type of Fredholm operators which are shown to have a certain con- tinuity in weak *** this,we will prove that the fundamental matrix solutions of k-th, k≥2,order linear systems of ordinary differential equations are continuous in coefficient matrixes with weak ***,Floquet multipliers and Lyapunov exponents for periodic systems are continuous in weak ***,for the scalar Hill’s equations,Sturm-Liouville eigenvalues, periodic and anti-periodic eigenvalues,and rotation numbers are all continuous in potentials with weak *** results will lead to many interesting variational problems.

关键词： continuity weak topology Fredholm operator linear system Hill’s equation eigenvalue rotation number Lyapunov exponent 34A30 34L40 37E45 34D08 58C07 46B50

A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

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science china Earth sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1,2, ZHOU Guangqing1, YAN Changxiang1, FU Weiwei1 & YOU Xiaobao1,3 1. International center for Climate and Environment sciences, Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 2. Jiangsu Key Laboratory of Meteorological Disaster, Nanjing University of Information science and Technology, Nanjing 210044, china 3. beijing Institute of applied Meteorology, beijing 100029, china International center for Climate and Environment sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing China beijing Institute of applied Meteorology Beijing China

A new 3DVAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3DVAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 21-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 420 m reach 0.63℃ and 0.34 psu.

关键词： data assimilation, 3DVAR, sea surface height, ARGO floats.