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491.
提出基于多目标决策理论的协同空战武器目标分配模型,并用进化多目标优化算法求解.空战是一个多阶段攻防过程,针对多数空战武器目标分配采用一次性完全分配、不考虑火力资源消耗等不足,构建多目标决策模型,在达到毁伤门限的前提下,同时对一次攻击后使敌编队的总期望剩余威胁最小和分配导弹消耗量最小两个目标函数寻优.提出用多目标离散粒子群-引力搜索算法(MODPSO-GSA)求解分配模型,该混合进化多目标优化算法结合二者优点,具有稳定的全局搜索能力并保证收敛到Pareto前沿.该算法可求得满足毁伤门限的不同耗弹量的分配方案最优解集以供指挥员决策参考.仿真算例验证了新模型及所提出MODPSO-GSA进化多目标优化求解算法的有效性. 相似文献
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Lucia Abbo Ester Antonucci Zoran Mikić Jon A. Linker Pete Riley Roberto Lionello 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The study concerns the streamer belt observed at high spectral resolution during the minimum of solar cycle 23 with the Ultraviolet Coronagraph Spectrometer (UVCS) onboard SOHO. On the basis of a spectroscopic analysis of the O VI doublet, the solar wind plasma parameters are inferred in the extended corona. The analysis accounts for the coronal magnetic topology, extrapolated through a 3D magneto-hydrodynamic model, in order to define the streamer boundary and to analyse the edges of coronal holes. The results of the analysis allow an accurate identification of the source regions of the slow coronal wind that are confirmed to be along the streamer boundary in the open magnetic field region. 相似文献
494.
梁继光 《北华航天工业学院学报》2007,17(2):34-35
以德育人是全面推进素质教育的关键,强化以德育人的认识,迎接新形势的考验与挑战,坚持把德育放在首位,这是个人成长、国家繁荣稳定的客观要求,也是实现伟大民族复兴的迫切需要. 相似文献
495.
J.Roshanian Z.Keshavarz 《中国航空学报》2007,20(1):86-96
Different multidisciplinary design optimization (MDO) problems are formulated and compared. Two MDO formulations are applied to a sounding rocket in order to optimize the performance of the rocket. In the MDO of the referred vehicle, three disciplines have been considered,which are trajectory, propulsion and aerodynamics. A special design structure matrix is developed to assist data exchange between disciplines. This design process uses response surface method (RSM) for multidisciplinary optimization of the rocket. The RSM is applied to the design in two categories: the propulsion model and the system level. In the propulsion model, RSM deter-mines an approximate mathematical model of the engine output parameters as a function of design variables. In the system level, RSM fits a surface of objective function versus design variables. In the first MDO problem formulation, two design variables are selected to form propulsion discipline. In the second one, three new design variables from geometry are added and finally, an optimization method is applied to the response surface in the system level in order to find the best result. Application of the first developed multidisciplinary design optimization procedure increased accessible altitude (performance index) of the referred sounding rocket by twenty five percents and the second one twenty nine. 相似文献
496.
实现人民健康是中国共产党治国理政的重大政治任务.习近平关于人民健康的重要论述以马克思主义经典作家关于实现人民健康的基本思想为理论基石,充分吸收了中国传统文化的有益成分与传统中医的健康养生理念,传承发展了中国共产党历来就重视和关注人民健康的理论与实践,与新时代全面建成小康社会的基本要求交相呼应.在新时代推进卫生与健康工作... 相似文献
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M. I. Desai G. M. Mason R. E. Gold S. M. Krimigis C. M. S. Cohen R. A. Mewaldt J. E. Mazur J. R. Dwyer 《Space Science Reviews》2007,130(1-4):243-253
Using high-resolution mass spectrometers on board the Advanced Composition Explorer (ACE), we surveyed the event-averaged
∼0.1–60 MeV/nuc heavy ion elemental composition in 64 large solar energetic particle (LSEP) events of cycle 23. Our results
show the following: (1) The Fe/O ratio decreases with increasing energy up to ∼10 MeV/nuc in ∼92% of the events and up to
∼60 MeV/nuc in ∼64% of the events. (2) The rare isotope 3He is greatly enhanced over the corona or the solar wind values in 46% of the events. (3) The heavy ion abundances are not
systematically organized by the ion’s M/Q ratio when compared with the solar wind values. (4) Heavy ion abundances from C–Fe exhibit systematic M/Q-dependent enhancements that are remarkably similar to those seen in 3He-rich SEP events and CME-driven interplanetary (IP) shock events. Taken together, these results confirm the role of shocks
in energizing particles up to ∼60 MeV/nuc in the majority of large SEP events of cycle 23, but also show that the seed population
is not dominated by ions originating from the ambient corona or the thermal solar wind, as previously believed. Rather, it
appears that the source material for CME-associated large SEP events originates predominantly from a suprathermal population
with a heavy ion enrichment pattern that is organized according to the ion’s mass-per-charge ratio. These new results indicate
that current LSEP models must include the routine production of this dynamic suprathermal seed population as a critical pre-cursor
to the CME shock acceleration process. 相似文献
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