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111.
The problem of orbit determination using one or two GPS satellites is discussed. Methods of getting initial values based on
linear translation is presented; the Secant method and the descend Newton iterative procedure and the continuation algorithm
are used synthetically to solve the nonlinear equations. Computer simulation shows that this algorithm can give preliminary
state of satellite orbit with a certain precision in short time. 相似文献
112.
吴刚 《哈尔滨商业大学学报(自然科学版)》1997,(3)
通过构造特殊的集类,并作用λ-π类方法,证明了由一维Wiener过程所构成的两个σ-代数σ(|WSI|s≤t)与σ(Ws:s≤t)之间严格的属于关系 相似文献
113.
The Poisson induction and coinduction procedures are used to construct Banach Lie–Poisson spaces as well as related systems of integrals in involution. This general method applied to the Banach Lie–Poisson space of trace class operators leads to infinite Hamiltonian systems of k-diagonal trace class operators which have infinitely many integrals. The bidiagonal case is investigated in detail. 相似文献
114.
XuHai Yang ZhiGang Li ChuGang Feng Ji Guo HuLi Shi GuoXiang Ai FengLei Wu RongChuan Qiao 《中国科学G辑(英文版)》2009,52(3):333-338
A geostationary (GEO) satellite may serve as a navigation satellite, but there is a problem that maneuvers frequently occur
and the forces are difficult to model. Based on the technique of determining satellite orbits by transfer, a predicted orbit
with high accuracy may be achieved by the method of statistical orbit determination in case of no maneuver force. The predicted
orbit will soon be invalid after the maneuver starts, and it takes a long time to get a valid orbit after the maneuver ends.
In order to improve ephemeris usability, the method of rapid orbit forecasting after maneuvers is studied. First, GEO satellite
movement is analyzed in case of maneuvers based on the observation from the orbit measurement system by transfer. Then when
a GEO satellite is in the free status just after maneuvers, the short arc observation is used to forecast the orbit. It is
assumed that the common system bias and biases of each station are constant, which can be obtained from orbit determination
with long arc observations. In this way, only 6 orbit elements would be solved by the method of statistical orbit determination,
and the ephemeris with high accuracy may be soon obtained. Actual orbit forecasting with short arc observation for SINOSAT-1
satellite shows that, with the tracking network available, the precision of the predicted orbit (RMS of O-C) can reach about
5 m with 15 min arc observation, and about 3 m with 30 min arc observation.
Supported by the National High Technology Research and Development Program of China (Grant No. 2006AA12Z322), the National
Basic Research Program of China (Grant No. 2007CB815503), and the West Light Program of Chinese Academy of Sciences (Grant
No. 2007LH01) 相似文献
115.
116.
117.
The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis
and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided
into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion
clearly. In this paper we choose the atomic principal quantum number asn=20. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distanced. Whend is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system
is integrable. Whend becomes smaller, there exists a critical valued
c. Ford>d
c, the system is near-integrable and the motion is regular. While chaotic motion appears ford<d
c, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the
metal surface. 相似文献
118.
丁昌明 《杭州师范学院学报(社会科学版)》2000,(3):7-9
本文讨论R~n中似梯度型系统,证明了三种吸引子的等价性并给出判别异缩轨存在的一个准则. 相似文献
119.
La Agusu T. Idehara M. Kamada T. Hayashi V. N. Manuilov O. Dumbrajs K. Yatsui W. Jiang 《International Journal of Infrared and Millimeter Waves》2005,26(5):637-655
Designs of cavities for fundamental and high harmonic operation in Large Orbit Gyrotron (LOG) are discussed. The fundamental operation allows one to use beam currents in the range from 200 A to 300 A achieve output power of the order of 9–10 MW at frequency 143.6 GHz. Mode competition calculations show that stable oscillations in the TE1,4 mode using high beam currents are possible even with the pitch factor 1.3 which is significantly lower than the design value 1.55. For the second harmonic operation, the maximum current used for excitation of the TE2,4 mode is 60 A and the optimum magnetic field is 7.6 T. A cavity design for fourth harmonic operation using the TE4,4 mode is also presented. 相似文献
120.
在动力系统的稳定性和混沌的研究中,引入了各种跟踪性质的概念。讨论了平均跟踪性质与渐近平均跟踪性质,证明了如果X是至少包含两点的紧致度量空间,iXX→X为恒同映射,则iX没有平均跟踪性质和渐近平均跟踪性质。此结果改进了两个已知结论。 相似文献