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11.
A numerical procedure for the calculation of the transonic dip of airfoils in the time domain is presented. A viscous-inviscid aerodynamic interaction method is taken to calculate the unsteady aerodynamic loads. In the present case the integral boundary layer equations are coupled with the Transonic Small Disturbance (TSD) Potential Equation. The coupling between structural motion and aerodynamic loads is carried out using State Space equation. It is solved by State Transition Matrix technique. Results are presented for NACA 64A010 and NLR 7301 airfoils with structural data from Isogai and DLR, respectively. Comparisons show good agreement with other numerical results. Certain deviations of experimental data taken from literature need more insight in the detailed test conditions. 相似文献
12.
公民对政府的监督是行政监督体系的重要组成部分,它主要包括公民决定政府领导人的去留,举报、检举政府违法行为和进行集体利益表达三种形式。然而,我国目前这三种形式还存在不少问题。扩大和保障公民的民主权利,健全公民的信访举报制度,完善公民的集体利益表达机制,是优化我国公民对政府监督的主要制度措施。 相似文献
13.
ected g 《桂林航天工业高等专科学校学报》2006,(2)
with primary goat embryonic fibroblast showed no difference from traditional feederlayer-based culture method used in mouse and human. The putative primary EG colonies were multilayer clumps ofcompact cel 相似文献
14.
15.
本文对质量矩控制导弹的动力学方程简化和控制系统的设计进行了研究。详细阐述了所提出的控制方法,介绍了径向基单隐层神经网络进行误差补偿的算法原理,用Lyapunov理论证明了所采用方法的稳定性。在给出了质量矩导弹的六自由度动力学方程和简化后的方程后,用所提出的方法设计控制系统。通过仿真分析,得出了本文所提出的方法具有较好的误差补偿能力的结论。 相似文献
16.
马凤贤 《中国民航学院学报》1989,(3)
本文为拓宽创新设计机构的思路,扼要地介绍了一种利用空间周转轮系,实观机械手臂的公转与自转动作要求的机构运动分析、设计方案及结构参考图。 相似文献
17.
Martin A. Lee 《Space Science Reviews》2007,130(1-4):221-229
Gradual solar energetic particle (SEP) events are evidently accelerated by coronal/interplanetary shocks driven by coronal
mass ejections. This talk addresses the different factors which determine the composition of the accelerated ions. The first
factor is the set of available seed populations including the solar wind core and suprathermal tail, remnant impulsive events
from preceding solar flares, and remnant gradual events. The second factor is the fractionation of the seed ions by the injection
process, that is, what fraction of the ions are extracted by the shock to participate in diffusive shock acceleration. Injection
is a controversial topic since it depends on the detailed electromagnetic structure of the shock transition and the transport
of ions in these structured fields, both of which are not well understood or determined theoretically. The third factor is
fractionation during the acceleration process, due to the dependence of ion transport in the turbulent electromagnetic fields
adjacent to the shock on the mass/charge ratio. Of crucial importance in the last two factors is the magnetic obliquity of
the shock. The form of the proton-excited hydromagnetic wave spectrum is also important. Finally, more subtle effects on ion
composition arise from the superposition of ion contributions over the time history of the shock along the observer’s magnetic
flux tube, and the sequence of flux tubes sampled by the observer. 相似文献
18.
Mauro Orlandini 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2742-2746
Broad-band spectra of accreting X-ray binary pulsars can be fitted by a phenomenological model composed of a power law with a high energy rollover above 10 keV, plus a blackbody component with a temperature of few hundred eV. While, at least qualitatively, the hard tail can be explained in terms of (inverse) Compton scattering, the origin of the soft component cannot find a unique explanation. Recently, a qualitative picture able to explain the overall broad-band spectrum of luminous X-ray pulsars was carried out by taking into account the effect of bulk Comptonization in the accretion column. After a review of these recent theoretical developments, I will present a case study of how different modeling of the continuum affect broad features, in particular the cyclotron resonance features in Vela X-1. 相似文献
19.
A.G. Lyne 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2716-2720
A recent multibeam pulsar survey of the outer Galactic plane at Parkes has discovered the first-known double-pulsar binary, a very compact double neutron star system in which both stars are observable as radio pulsars. In this review, we briefly describe the discovery and the studies which have been enabled by the unique properties of the system. These range from the most precise confirmation yet of the theory of general relativity, with the possibility of even more new tests and the measurement of second-order post-Newtonian effects, to studies of the magnetospheres and emission properties of the two pulsars. The discovery also results in a significant increase in the expected rate of occurrence of the mergers of double neutron star systems, and hence the rate of detection of such events by the new ground-based gravitational wave detectors. 相似文献
20.
秦翠霞 《沈阳航空工业学院学报》1997,14(4):80-84
本文从我国产业结构调整的现状及存在的问题出发,针对一般加工产业生产能力过大,高水平的加工能力不足这一突出问题进行了原因分析,在此基础上,就我国加速优化产业结构的客观基础和可能,提出了关于加大产业结构调整力度的七点思考建议。 相似文献