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181.
182.
Resonance transitions associated to weak capture in the restricted three-body problem 总被引:1,自引:1,他引:0
Edward Belbruno Francesco Topputo Marian Gidea 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,42(8):1330-1351
An interesting dynamics is studied in the restricted three-body problem where a particle abruptly transitions between resonance states, called a resonance hop. It occurs in a region about the secondary mass point which supports weak capture. This region, called a weak stability boundary, was recently proven to give rise to chaotic dynamics. Although it was numerically known that the resonance hop was associated with this boundary, this process was not well understood. In addition, the dynamical structure of the weak stability boundary has not been well understood. In this paper, we give a way to reveal the global structure of the weak stability boundary associated to resonance motions. This structure is shown to be surprisingly rich in resonant periodic motions interconnected by invariant manifolds. In this case, nearly all the motions are approximately resonant in nature where resonance hops can occur. The correlation dimension of orbits undergoing resonant motions, associated to the weak stability boundary, is also examined. The dynamics analyzed in the present paper is related to that studied by J. Marsden et al. under the perspective of Lyapunov orbits and the associated invariant manifolds. Applications are discussed. 相似文献
183.
用光弹法对熊猫型单模保偏光纤的截面应力状态及外加应力对其偏振轴方向的影响做了理论分析与实验测量,绘出了测试曲线,演明了光弹法可以快速准确地测定该光纤的偏振轴方向。 相似文献
184.
以往的数控系统只能插补平行坐标平面的圆弧,本文根据坐标系旋转的原理,提出了一种可以插补任意平面圆弧曲线、且可以满足控制实时性要求的插补算法,以简化编程,提高加工精度。 相似文献
185.
为提高液浮陀螺仪在双轴转台上的标定精度,将双轴转台的误差,陀螺仪的安装误差以及陀螺仪自身的静态误差建立在陀螺仪的标定模型中,在1g重力场中分别建立了16位置和20位置陀螺仪的标定方案。采用误差分离技术与最小二乘法来标定液浮陀螺仪的误差模型系数。与传统的8位置标定方法相比,本文所提出的两种多位置标定方法可以自动规避或补偿双轴转台误差,也可消除不易测量的陀螺仪安装误差对标定结果的影响,以此来提高液浮陀螺仪的标定精度。最后对提出的多位置标定方法进行误差分析,验证了方法的有效性。 相似文献
186.
卫星平台搭载光学载荷对空间运动目标进行跟踪指向技术已经成为卫星发展的重点,为了提升卫星光轴的指向范围、跟踪精度和机动性,仅依靠卫星的姿态调整已无法提升卫星光轴的性能。通过对由卫星姿态、星载光电转台和快反镜组成的卫星复合光轴指向系统的分析,需三者协同工作,输出有效叠加,才能有效提升卫星光轴的指向范围、跟踪精度和机动性。对卫星姿态控制系统、星载光电转台控制系统、快反镜控制系统进行研究建模后,确定了三者的作动频带。通过建立辅助PQ单位反馈系统,运用频率响应法设计复合指向控制器,模拟某轨道的卫星与跟踪目标的相对运动轨迹作为仿真模型的输入。仿真数据表明卫星光轴的跟踪指向误差由0.6°下降到了0.05°,证明了复合指向控制律有效提升了卫星光轴的性能。 相似文献
187.
James B. Pezent Rohan Sood Andrew Heaton 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(9):2981-2994
Regions outside the reach of traditional propulsion systems or the ones that require significant propellant, may be reached by harnessing the solar radiation pressure and leveraging coupled dynamics to maneuver a sail-based spacecraft. Earth-trailing orbits have recently been investigated for getting a unique perspective of the Sun while maintaining the spacecraft in close proximity to Earth. Vertical orbits trailing the Earth exhibit the additional capability to view the Sun from above and below the ecliptic plane. In this work, families of sail-based orbits are explored for varying Earth-trailing angles and Z amplitudes in the Sun-Earth circular restricted three-body problem. Optimization is carried out to ensure that the non-traditional vertical orbits exhibit a constant pitch angle control history, as well as symmetry across the X-Y plane. The stability of the resulting orbit families is assessed using an extension of Flouquet theory to Differential Algebraic Equations. Results indicate that sail-based Earth-trailing vertical orbits can be more stable than traditional sub-L1 sail-based vertical orbits. 相似文献
188.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2020,65(5):1518-1527
Attitude is the important parameter for active debris removal and collision avoidance. This paper deduced the spin axis orientation and spin period of the rocket body, CZ-3B R/B (NORAD ID 38253), using the satellite laser ranging and light curve data measured with single-photon detector at Graz station. The epoch method and LC & SLR residuals fitting were combined to determine these values. The derived right ascension angle was around 220°, the declination angle was near 64° and the sidereal period was calculated to be 117.724 s, for 2017-07-03. The results derived from the two distinct methods were mutually validated. Rocket bodies are a major contributor to space debris and this work provides a reference for attitude determination and attitude modelling. 相似文献
189.
190.
针对圆型限制性三体问题共线平动点附近周期/拟周期轨道下的相对运动问题,提出一种新的、通用的解析研究方法。在周期/拟周期轨道近似解析解的基础上,结合微分修正方法,获得了精确的周期/拟周期轨道。对周期/拟周期轨道的单值矩阵进行分析,同时借鉴Floquet理论核心思想,建立了六个相对运动模态,并将相对运动表示为六个相对运动模态的线性组合,获得了相对运动的近似解析解。最后在地-月系统圆型限制性三体问题下,以L1点作为研究对象,分别以Halo轨道、Lissajous轨道和Lyapunov轨道为参考轨道,对相对运动模态和相对运动进行仿真分析,说明了相对运动模态的正确性以及相对运动近似解析解的有效性。 相似文献