A new lunar absolute control point: established by images from the landing camera on Chang'e-3     

Fen-Fei Wang  Jian-Jun Liu  Chun-Lai Li  Xin Ren  Ling-Li Mu  Wei Yan  Wen-Rui Wang  Jing-Tao Xiao  Xu Tan  Xiao-Xia Zhang  Xiao-Duan Zou  Xing-Ye Gao 《中国天文和天体物理学报》2014,(12)

The establishment of a lunar control network is one of the core tasks in selenodesy, in which defining an absolute control point on the Moon is the most important step. However, up to now, the number of absolute control points has been very sparse. These absolute control points have mainly been lunar laser ranging retroreflectors, whose geographical location can be observed by observations on Earth and also identified in high resolution lunar satellite images. The Chang'e-3(CE-3) probe successfully landed on the Moon, and its geographical location has been monitored by an observing station on Earth. Since its positional accuracy is expected to reach the meter level, the CE-3 landing site can become a new high precision absolute control point. We use a sequence of images taken from the landing camera, as well as satellite images taken by CE-1 and CE-2, to identify the location of the CE-3 lander. With its geographical location known, the CE-3 landing site can be established as a new absolute control point, which will effectively expand the current area of the lunar absolute control network by 22%, and can greatly facilitate future research in the field of lunar surveying and mapping, as well as selenodesy.  相似文献   

Isolation and biological characteristics of aerobic marine magnetotactic bacterium YSC-1     

高峻潘红苗  岳海东宋涛 赵勇陈冠军  吴龙飞肖天 《中国海洋湖沼学报》2006,24(4):358-363

1 INTRODUCTION Magnetotactic bacteria are able to respond and orient along the direction of terrestrial or artificial magnetic field, a behavior referred to as magneto- taxis. In the majority of magnetotactic bacteria, the magnetosomes are 25–120 nm in d…  相似文献   

Evolution characteristics of the central black hole of a magnetized accretion disc     

D. X. Wang  K. Xiao  W. H. Lei 《Monthly notices of the Royal Astronomical Society》2002,335(3):655-664

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国标图纸的分片输出     

肖洪生 《广东海洋大学学报》1995,(2)

本文阐述了国标图纸分片输出的意义与方法；通过举例，ＡｕｔｏＣＡＤ用户能够容易地掌握使用本文中所述的分片输出方法，用小幅面图形输出设备绘制大幅面的工程技术图纸。  相似文献   

A New Method of Identifying 3D Null Points in Solar Vector Magnetic Fields   总被引：7，自引：0，他引：7  

Hui Zhao  Jing-Xiu Wang  Jun Zhang  Chi-Jie Xiao National Astronomical Observatories  Chinese Academy of Sciences  Beijing 《中国天文和天体物理学报》2005,5(5):443-447

Employing the Poincare index of isolated null-points in a vector field, we worked out a mathematical method of searching for 3D null-points in coronal magnetic fields. After introducing the relevant differential topology, we test the method by using the analytical model of Brown & Priest. The location of null-point identified by our method coincides precisely with the analytical solution. Finally we apply the method to the 3D coronal magnetic fields reconstructed from an observed MDI magnetogram of a super-active region (NOAA 10488). We find that the 3D null-point seems to be a key element in the magnetic topology associated with flare occurrence.  相似文献   

GEOLOGY AND GEoCHEMISTY OF THE GAOTAIGOU BORON DEPOSIT IN SOUTHERN JILIN, CHINA     

Feng Xiaozhen  Xiao Ye  Liu Changxue 《化工矿产地质》2008,30(4)

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A navigational primitive: biorobotic implementation of cycloptic helical klinotaxis in planar motion     

Long  J.H.  Jr. Lammert  A.C. Pell  C.A. Kemp  M. Strother  J.A. Crenshaw  H.C. McHenry  M.J. 《Oceanic Engineering, IEEE Journal of》2004,29(3):795-806

A broad diversity of microorganisms and larval aquatic animals swim along a helical trajectory. Helical movement toward or away from stimuli involves the detection of gradients, alteration of the helical trajectory, and gradient tracking. Using sensory and neural circuitry models from swimming simulations of tadpole-like ascidian larvae (Phylum Chordata, Subphylum Urochordata), we built and tested a single-sensor, surface-swimming, tail-flapping robot that swims up a light gradient and holds station at an orbital around an area of high intensity. We implemented the same neural circuitry in a terrestrial, wheeled robot with a single photoresistor; it exhibited similar navigational behavior. We also mathematically modeled single-sensor robots navigating in plane. The simulated robots showed the importance of sensor placement and excitation field on navigational behavior. When the sensor placement and excitation field of the simulated robot matched that of the embodied robots, navigational behavior was similar. These results 1) tested and supported a proposed neural circuitry model, 2) showed the simplicity and effectiveness of using a single light sensor for navigation, and 3) demonstrated the use of helical motion in two dimensions.  相似文献   

The Structure on the Western Flank of the Gregory Rift (Kenya). Part I. The Crust     

P. K. H. Maguire  R. E. Long 《Geophysical Journal International》1976,44(3):661-675

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天鹅座X-1硬X射线的能量谱     

马宇蒨  李光华  张承模  钱跃民  肖谦益  陆柱国  吴枚  戴长江  李惕碚  顾逸东  张希元 《中国天文和天体物理学报》1989,(4)

1985年9月22日,我们用空间硬X射线望远镜HAPI-2,在我国的高空气球上,对天鹅座X-1进行了观测,望远镜几何面积为140cm~2,观测能区20—200keV,空间定向精度±0.2°。获得的硬X射线能谱陡,总辐射能流LX～1.0×1~(37)erg/sec,低于常规态。本文将介绍望远镜的性能和观测过程,能谱分析的结果,并对当时天鹅座X-1可能的“态”进行讨论。  相似文献   

Recruitment of postlarval prawns,Penaeus Orientalis,to a tidal estuary of Jiaozhou Bay,China     

Xiao Yongshun  Liu Ruiyu  Cui Yuheng 《中国海洋湖沼学报》1988,6(4):290-299

PostlarvalPenaeus orientalis kishinouye were simultaneously sampled at three fixed stations near the mouth of the Dagu River estuary in northwestern Jiaozhou Bay, China, at hourly intervals over a 49-h period in mid-June, 1984. The purpose of this sampling was to investigate the prawn’s recruitment into estuaries from coastal areas. The abundance of the postlarvae varied considerably between stations and time, but they tended to concentrate at the surface. Maximum entropy spectral analysis was first applied in the study of prawn recruitment and it revealed that variations in abundance involved a pronounced 12.4 hr cycle. It was concluded that natural tidal cycles had a strong influence on the changes of postlarval abundance, in contrast with the minor effects of diet and other environmental cycles. A tidally varying cross-river gradient of postlarval density was found. During flood tides the postlarvae were more abundant in the axis of the channel than over the banks. The opposite held true during ebb tides. Mechanisms of the postlarval recruitment are discussed in terms of alternating movements of the postlarvae between the banks and the channels in response to tidal cycles. Contribution No. 1485 from the Institute of Oceanology, Academia Sinica  相似文献