非潮汐海洋运动对地球动力学扁率变化的贡献   总被引：1，自引：1，他引：0       下载免费PDF全文

胡小工  Jian-Li CHEN  黄珹  B.D.Tapley  C.R.Wilson 《地球物理学报》2004,47(3):428-432

通过考察全球海洋环流数值模型以及TOPEX/Poseidon海洋测高数据,得到结论：1997/1998年后的部分J2异常变化可能来自海洋环流变化导致的质量重新分布,具体地说是太平洋环流变化导致的从高纬地区向低纬地区的质量迁移. 本工作表明来自于海洋内部温盐效应的变化对J2异常变化有重要贡献,进一步证实了卫星激光测距资料所得结果的可靠性.  相似文献   

中国大陆及周边地区的水平应变场   总被引：58，自引：11，他引：47       下载免费PDF全文

李延兴  李智  张静华  黄珹  朱文耀  王敏  郭良迁  张中伏  杨春花 《地球物理学报》2004,47(2):222-231

推导并建立了块体的两种弹性运动方程：块体的整体旋转与均匀应变方程和块体的整体旋转与线性应变方程. 应用统计学原理,使用西域、青藏和华北块体上的GPS站速度数据,对这两种弹性运动方程与刚体运动方程模拟块体站速度的无偏性和有效性进行了统计检验. 检验结果表明,块体的整体旋转与线性应变方程是描述块体运动的最优模型. 将中国大陆划分为10个块体,应用块体的整体旋转与线性应变方程和块体上的GPS站速度估计了各个块体上的旋转与应变参数,按照1°×1°的间距计算了中国大陆及周边地区上1005个点的应变参数,分析了中国大陆及周边地区应变场的基本特征. 用本文方法得到的主压应变方向与地质学方法和测震学方法得到的主压应力轴方向具有很好的一致性(华南块体除外).  相似文献   

Chemical Classification of Space Debris     

LI Chunlai  ZUO Wei  LIU Jianjun  OUYANG Ziyuan National Astronomical Observatories  Chinese Academy of Sciences  Beijing  Institute of Geochemistry  Chinese Academy of Sciences  Guiyang  Guizhou Graduate School  Chinese Academy of Sciences  Beijing 《《地质学报》英文版》2004,78(5):1090-1093

Space debris, here referring to all non-operating orbital objects, has steadily increased in number so that it has become a potential barrier to the exploration of space. The ever-increasing number of space debris pieces in space has created an increasingly threatening hazard to all on-the-orbit spacecraft, and all future space exploration activities have to be designed and operated with respect to the increasing threat posed by space debris. Generally, space debris is classified as large, medium and small debris pieces based on their sizes. The large debris piece is easily catalogued, but medium to small debris pieces are very difficult to track and also quite different in damage mechanisms from the large ones. In this paper, a scheme of chemical classification of space debris is developed. In our scheme, the first-order classification is employed to divide space debris into two groups: natural  相似文献   

LUNARINFO: A Data Archiving and Retrieving System for the Circumlunar Explorer Based on XML/Web Services     

ZUO Wei  LI Chunlai  OUYANG Ziyuan  LIU Jianjun  XU TaoNational Astronomical Observatories  Chinese Academy of Sciences  Beijing  Institute of Geochemistry  Chinese Academy of Sciences  Guiyang  Guizhou Graduate School  Chinese Academy of Sciences  Beijing 《《地质学报》英文版》2004,78(5):1094-1103

It is essential to build a modern information management system to store and manage data of our circumlunar explorer in order to realize the scientific objectives. It is difficult for an information system based on traditional distributed technology to communicate information and work together among heterogeneous systems in order to meet the new requirement of Internet development. XML and Web Services, because of their open standards and self-containing properties, have changed the mode of information organization and data management. Now they can provide a good solution for building an open, extendable, and compatible information management system, and facilitate interchanging and transferring of data among heterogeneous systems. On the basis of the three-tiered browse/server architectures and the Oracle 9i Database as an information storage platform, we have designed and implemented a data archiving and retrieval system for the circumlunar explorer-LUNARINFO. We have also  相似文献   

The Importance of Time Synchronization in the Local Networks of the Science and Application Center for Lunar and Deep-space Exploration     

LIU Guoping  OUYANG Ziyuan  LI Chunlai  LIU Jianfeng National Astronomical Observatories  Chinese Academy of Sciences  Beijing  Peking University of Aeronautics  Astronautics  Beijing 《《地质学报》英文版》2004,78(5):1104-1108

The data acquisition stations and the data processing center of the Science and Application Center for Lunar and Deep-space Exploration (SACLuDE) are located at different geographical sites. They respectively have their own local networks and interconnect with each other through access to the core data network. This paper describes the clock drift in the computer and other networked devices building up the infrastructure of the above local networks. The network time variance of the stochastic model is also estimated. The poor precision of network synchronization will bring about potential hazards to the network operation and application running in the networks, which is clarified in the present paper. At the end of the paper, a cost-effective and feasible solution is proposed based on the Global Position System (GPS) and the Network Time Protocol (NTP).  相似文献   

始新世以来地球轨道偏心率的演化     

YIN Zhi-qiang )  HAN Yan-ben )  XU Dao-yi )  YAO Yi-Min )  HAN Yong-gang ) ) National Astronomical Observatories  Chinese Academy of Sciences  Beijing    ) Institute of Geology  China Earthquake Administration  Beijing    ) Geological Scientific Research Institute of Shengli Oilfield Company SINOPEC  Dongying 《地层学杂志》2007,(Z2)

地球轨道要素的变化已作为确定地质年表的一种重要依据。应用地球轨道参数变化理论计算值来进行小波分析,结果清楚地展示出偏心率值约100ka、405ka、1Myr和2.3Myr等周期成份的随时间变化特征,100ka和405ka周期的振幅强度的变化成反相位关系,2.3Myr周期对100ka和405ka周期成份有调制作用。0—51Ma范围内变化较为稳定的地球轨道偏心率值的变化分析可以为地质年龄的划分和对比提供一定的参考。  相似文献   

A Peculiar Broad Line Radio Galaxy 1938-155： VLA Observation at 90 cm     

Tao An  Xiao-Yu Hong  Wen-Xia Feng  Jun-Hui Zhao Shanghai Astronomical Observatory  Chinese Academy of Sciences  Shanghai  National Astronomical Observatories  Chinese Academy of Sciences  Beijing Harvard-Smithsonian Center for Astrophysics  Garden Street  MS  Cambridge  MA 《中国天文和天体物理学报》2004,4(6):527-532

We observed 1938-155, a broad line radio galaxy (BLRG), with the Very Large Array (VLA) at 90cm with an angular resolution of 6.8" × 4.0". The source consists of two components separated by 4 arcsec (- 20kpc, for H0 = 65km s-1 Mpc-1, q0 = 0.5) along the SE-NW direction. Both components show steep-spectra with a similar spectral index α - 0.83 ± 0.07 (Sv ∝ v-α). The bright double components are surrounded by a low-brightness cocoon. The radio properties of the two bright components are consistent with the hot spots produced by twin jets. An upper limit of - 0.0008 for the core dominance parameter (R) is inferred, suggesting there is no prominent radio core in the source. Assuming a modest viewing angle 30f77, a jet velocity is estimated - 0.07 c, based on the jet to counter-jet brightness ratio (J). The lower limit in jet speed inferred is consistent with no Doppler beaming effect on the jet. The radio galaxy 1938-155 could be an exceptional BLRG with no prominent radio core or jet.  相似文献   

On the fairness of the main galaxy sample of SDSS     

Ke-Lai Meng  Bin Ma  Jun Pan  Long-Long Feng Purple Mountain Observatory  Chinese Academy of Sciences  Nanjing  China  National Astronomical Observatories  Beijing 《中国天文和天体物理学报》2011,(6)

Flux-limited and volume-limited galaxy samples are constructed from the Sloan Digital Sky Survey(SDSS)data releases DR4,DR6 and DR7 for statistical analysis.The two-point correlation functionsξ(s),monopole of three-point correlation functionsζ0,projected two-point correlation function wp and pairwise velocity dispersionσ12 are measured to test if galaxy samples are fair for these statistics.We find that with the increment of sky coverage of subsequent data releases in SDSS, ξ(s)of the flux-limited sample is...  相似文献   

A computational method to help identify and measure metallines in high resolution QSO spectra     

David Tytler  David Kirkman  Jeffery Lee  Benjamin Ou 《中国天文和天体物理学报》2011,(11)

A computational code is developed to help identify metal absorption linesin high resolution QSO spectra,especially in the Lyα forest.The input to the codeincludes a list of line central wavelengths,column densities and Doppler widths.Thecode then searches for candidate metal absorption systems and assesses the probability that each system could be real.The framework of the strategy we employ isdescribed in detail and we discuss how to estimate the errors in line profile fitting thatare essential to identifi...  相似文献   

Time series data correction for the Chang'E-1 gamma-ray spectrometer     

Li-Yan Zhang    Yong-Liao Zou  Jian-Zhong Liu  Jian-Jun Liu  Ji Shen  Ling-Li Mu  Xin Ren  Wei-Bin Wen  Chun-Lai Li National Astronomical Observatories  Chinese Academy of Sciences  Beijing  China  Graduate University of Chinese Academy of Sciences  Beijing 《中国天文和天体物理学报》2011,(6)

The main goal of the gamma-ray spectrometer(GRS) onboard Chang'E1(CE-1) is to acquire global maps of elemental abundances and their distributions on the moon,since such maps will significantly improve our understanding of lunar formation and evolution.To derive the elemental maps and enable research on lunar formation and evolution,raw data that are received directly from the spacecraft must be converted into time series corrected gamma-ray spectra.The data correction procedures for the CE-1 GRS time series...  相似文献