空间核动力技术概览与发展脉络初探

在概略介绍现有技术方案基础上,初步探讨空间核动力技术的发展脉络,并分析其未来发展方向.基于固体核反应堆的空间核电源、核电推进及核热推进,是经过试验验证可行、具有一定技术基础并可预期实现空间应用的空间核动力技术.更先进的概念方案包括:基于气体核反应堆的核电源/核热推进、脉冲核爆推进、核裂变碎片推进等,它们的性能逐代跨越直至逼近理论极限.要充分利用核能的潜力,一方面需要提高单位质量核燃料的核能释放率,另一方面也需要减少核反应产物动能转换为无轨热运动的比率.核能潜力的充分利用需要以增加系统质量为代价.为满足未来宽广的空间任务需求,多物理机制驱动的大深度变工况一体化核能空间动力系统是未来必然发展趋势.     

Cutting the bread

Why the draft Treaty on the Prevention of the Placement of Weapons in Outer Space, the Threat or Use of Force Against Outer Space Objects (PPWT) will not work - whereas the Code of Conduct for Outer Space Activities may.     

Precursor to an African Space Agency: Commentary on Dr Peter Martinez “Is there a need for an African Space Agency?”

In 2012 a working group was established to formulate the African space policy and strategy which would lead to the establishment of an African Space Agency (ASA). Dr Peter Martinez asserts in his article “Is there a need for an African Space Agency?” [1] that the arguments that have been posited in support of an ASA are flawed; namely the arguments of the existing example of the European Space Agency (ESA), and that an ASA would lead to fostering competition, synergy, industrial development and capacity building. While this viewpoint agrees that all the perfect conditions may not exist at present for the creation of an ASA, it addresses some of the issues raised by Martinez, and proposes ideas to foster intra-regional cooperation.     

空间信息对抗能力与技术需求

在陆、海、空、天、电战争范畴,空间攻防对抗是战略制高点。从美军的空间对抗的发展和变化,折射出未来的空间对抗需求已由“确保摧毁”向“确保生存”的战略概念转变,由“硬杀伤”向“软能力”倾斜。从需求出发,提出未来空间信息对抗能力设想,以及实现这些能力的主要关键技术。     

Kinetic Excitation Mechanisms for ION-Cyclotron Kinetic Alfvén Waves in Sun-Earth ConnectionI

We study kinetic excitation mechanisms for high-frequency dispersive Alfvén waves in the solar corona, solar wind, and Earth's magnetosphere. The ion-cyclotron and Cherenkov kinetic effects are important for these waves which we call the ion-cyclotron kinetic Alfvén waves (ICKAWs). Ion beams, anisotropic particles distributions and currents provide free energy for the excitation of ICKAWs in space plasmas. As particular examples we consider ICKAW instabilities in the coronal magnetic reconnection events, in the fast solar wind, and in the Earth's magnetopause. Energy conversion and transport initiated by ICKAW instabilities is significant for the whole dynamics of Sun-Earth connection chain, and observations of ICKAW activity could provide a diagnostic/predictive tool in the space environment research. This revised version was published online in August 2006 with corrections to the Cover Date.     

空间群Pn3mPn3P23子群链耦合系数的计算

本文利用陈金全教授的本征函数法计算了Pn3m Pn3 P2 3空间群的母分系数。最后的计算结果表明 ,用陈金全教授的本征函数法所求得的母分系数确实满足幺正、归一性 ,同时也证明了本征函数法对于求母分系数同样适用     

The land remote sensing commercialization Act of 1984

This article examines the effect that private-sector remote sensing activities might have on the international community and on the future of international cooperation in space. It describes in detail The Land Remote Sensing Commercialization Act of 1984, recently passed by the US Congress and signed by President Reagan. The article concludes that it is possible to develop domestic regulations that balance the economic interests of the private sector with the legal and political concerns of the international community.     

面向持续战域感知的近空间飞行器技术

未来战争呈全空域立体化发展趋势,近空间的深入探索和有效利用日益受到重视.本文从热力学特性和电离特性角度,概述了近空间大气环境.重点以持续的战域感知为军事应用背景,介绍了现有的C4ISR能力,进而归纳评述了相关近空间飞行器的技术发展、工程设计、概念应用.分析指出,近空间无人HALE飞机具有填补持续的C4ISR能力中所有空缺的潜力.     

优化抗差自适应滤波器在深组合导航中的应用

为了提高惯性/卫星深组合导航系统的滤波性能,在抗差自适应滤波算法的 基础上,研究了一种优化抗差自适应滤波算法。该算法通过比较实际预测残差协方差矩 阵和理论协方差阵的差值来生成自适应因子,从而优化抗差自适应滤波。将所研究的算 法应用于惯性/卫星深组合导航系统, 在高动态环境下进行仿真验证, 并与常规卡尔曼 滤波、抗差自适应滤波进行比较。结果表明,优化算法能有效地控制观测异常和动态模 型异常对状态参数估值的影响,所得组合导航位置误差和速度误差明显减小,提高了组 合导航系统的滤波精度。