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991.
WU HaiTao LU XiaoChun ZOU DeCai & HAN Tao National Time Service Center Chinese Academy of Sciences Xi'an China Key Laboratory of Precision Navigation Timing Technology 《中国科学:物理学 力学 天文学(英文版)》2011,(6)
Navigation augmentation technology is one of the most common methods to increase the continuity,reliability and integrity of the global satellite navigation system.The concept of volunteer augmentation navigation (VNA) is proposed and the elements and topological structure of VNA are also analyzed in this paper.The study focuses on the neural network model that volunteers and ordinary users use modern communication information network to exchange self-organizing information.The neural cell model of Voluntee... 相似文献
992.
ZHOU ShanShi HU XiaoGong WU Bin LIU Li QU WeiJing GUO Rui HE Feng CAO YueLing Wu XiaoLi ZHU LingFeng SHI Xin & TAN HongLi Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China Graduate University of Chinese Academy of Sciences Beijing Beijing Global Information Application Development Center Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(6)
Aiming at regional services,the space segment of COMPASS (Phase I) satellite navigation system is a constellation of Geostationary Earth Orbit (GEO),Inclined Geostationary Earth Orbit (IGSO) and Medium Earth Orbit (MEO) satellites.Precise orbit determination (POD) for the satellites is limited by the geographic distribution of regional tracking stations.Independent time synchronization (TS) system is developed to supplement the regional tracking network,and satellite clock errors and orbit data may be obtai... 相似文献
993.
YANG YuJuan & YAN Biao School of Materials Science Engineering Tongji University Shanghai China Shanghai Key Lab of Development Application for Metal Functional Materials 《中国科学:物理学 力学 天文学(英文版)》2011,(5)
With the multi-phase field model, the unidirectional solidification with constant velocity growth and variable velocity growth of the CBr4-C2Cl6 eutectic alloy is simulated in three dimensions. The simulated results with constant velocity growth show that with the increase of pulling velocity, the morphology of the CBr4-C2Cl6 alloy evolves in the sequence of lamellar merging →lamellar-rod transition→stable lamellar growth→oscillating growth→lamellar branching. A morphology selection map is established with ... 相似文献
994.
CHEN RunFeng MA Cong PAN JingFang ZHENG Chao & HUANG Wei Key Laboratory for Organic Electronics & Information Displays 《中国科学:物理学 力学 天文学(英文版)》2011,(5)
The electronic structures and optical properties of oligothiophene substituted spirofluorenes are investigated theoretically with semi-empirical quantum chemical calculations. A theoretical investigation of the interaction between two perpendicular π-systems of various oligothiophene substituted spirofluorenes is conducted. The results demonstrate that the interaction between two perpendicular branches is reduced by oligothiophene substitutions. Photoexcitation induced relaxation is mainly located on one of... 相似文献
995.
LI ZhiHong LI ErTao SU Jun LI YunJu BAI XiXiang GUO Bing WANG YouBao CHEN YongShou HOU SuQing ZENG Sheng LIAN Gang SHI JianRong & LIU WeiPing China Institute of Atomic Energy Beijing China National Astronomical Observatories Chinese Academy of Sciences Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(Z1)
Lithium isotopes have attracted an intense interest because the abundance of both 6Li and 6Li from big bang nucleosynthesis (BBN) is one of the puzzles in nuclear astrophysics. Many investigations of both astrophysical observation and nucleosynthesis calculation have been carried out to solve the puzzle, but it is not solved yet. Several nuclear reactions involving lithium have been indirectly measured at China Institute of Atomic Energy, Beijing. The Standard BBN (SBBN) network calculations are then perfo... 相似文献
996.
OSHIMA M TOH Y KOIZUMI M KIMURA A Hatsukawa Y MORIKAWA T NAKAMURA M SUGAWARE M KUSAKARI H 《中国科学:物理学 力学 天文学(英文版)》2011,(Z1)
A new rotational band has been identified and assigned to 188Au for the first time using the 173Yb(19F,4nγ) reaction at the beam energies of 86 and 90 MeV. This band is proposed to be built on the πh9/2 νi13/2 configuration by comparing the band properties with known bands in neighboring nuclei. The prolate-to-oblate shape transition through triaxial shape has been proposed to occur around 188Au for the πh9/2 νi13/2 bands in odd-odd Au isotopes on the basis of total Routhian surface (TRS) calculations. 相似文献
997.
CHEN Liang ZHOU XiaoHong ZHANG YuHu ZHANG ShuangQuan & ZHU LiHua Institute of Modern Physics Chinese Academy of Sciences Lanzhou China Graduate University of Chinese Academy of Sciences Beijing State Key Laboratory of Nuclear Physics Technology School of Physics Peking University Beijing China Institute of Atomic Energy Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(Z1)
High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[642], 3/2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3/2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3/2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated wit... 相似文献
998.
HAO Liang & LONG GuiLu Key Laboratory for Atomic Molecular NanoSciences 《中国科学:物理学 力学 天文学(英文版)》2011,(5)
In this work, we demonstrated a fixed-point quantum search algorithm in the nuclear magnetic resonance (NMR) system. We constructed the pulse sequences for the pivotal operations in the quantum search protocol. The experimental results agree well with the theoretical predictions. The generalization of the scheme to the arbitrary number of qubits has also been given. 相似文献
999.
ZHONG ZhiYong ZHANG HuaiWu TANG XiaoLi JING YuLan BAI FeiMing & LIU Shuang State Key Laboratory of Electronic Thin Films Integrated Devices University of Electronic Science Technology of China Chengdu China School of Optoelectronic Information 《中国科学:物理学 力学 天文学(英文版)》2011,(7)
The microstructure and magnetic properties of cobalt ferrite thin films deposited by the sputtering method on an Fe3O4 under-layer were investigated at different post-annealing temperatures.Results show that the Fe3O4 under-layer can accelerate the grain growth of cobalt ferrite films due to the phase transformation of the Fe3O4 under-layer at about 400°C-500°C.By introducing the Fe3O4 under-layer,cobalt ferrite nanocrystalline thin films with high coercivity can be obtained at lower post-annealing temperat... 相似文献
1000.
ZHANG Jun JIN YaXin WANG HanBin YE Cong TONG WeiMing & WANG Hao Faculty of Physics Electronic Technology Hubei University Wuhan China 《中国科学:物理学 力学 天文学(英文版)》2011,(7)
Highly textured Ni nanowire arrays were fabricated into anodic aluminum oxide(AAO) templates by pulse DC electrodeposition.The applied voltage and pH value of electrolytes were found strongly affecting the microstructure and magnetic properties of Ni nanowire arrays.Low applied potential and pH value both prefer to form polycrystalline fcc Ni nanowires.Increasing the applied potential or pH value favors the Ni [220] texture and even eventually forms the [220] oriented single crystal Ni wires,while exorbitan... 相似文献