空间碎片碰撞预警研究

介绍了空间碎片的分布和危害，阐明了航天器进行碎片预警规避的必要性，讨论了碎片碰撞预警技术中的关键问题，用已有的碰撞和规避实例对自行研制的软件进行了计算检验，结果证明了软件的正确性，也说明了国内进行碎片预警工作的可行性．     

论空间交会中的径向连续推力机动与N次推力机动

文章从相对运动和绝对运动两方面分析径向小推力连续机动在空间交会V-bar接近中的运动规律，对冲量型、连续型和N次推力三类径向推力策略的性能进行比较。径向小推力连续机动的相对运动轨迹呈“旋轮线”型式。N次机动策略变轨速度总和与冲量型转移及连续推力机动所需的变轨速度相等，轨道控制能力提高，视界角比冲量型转移的视界角小，转移时间比连续型推力所需时间减少，且能适应范围更广的推力阶。N次推力机动策略综合性能优良。     

空间目标一维距离像重构的线性规划方法

高分辨一维距离像是空间目标故障诊断与识别的重要手段。针对典型的空间目标 ,文章采用稀疏成份分析法研究了一维距离像的超分辨重构和特征提取问题。将处理实信号的基寻踪方法推广到复信号 ,并利用约束最小二乘解提出了一种次优的距离像重构算法 ,实现了空间目标散射中心的有效分离。数值结果验证了其合理性和有效性。     

空间液滴蒸发实验中液滴图像的无损压缩算法

为了提高空间液滴蒸发实验中图像无损压缩率, 根据连续采集到的液滴图像之间相关性很大的特点, 提出了一种基于JPEG-LS和帧间预测误差编码的图像序列无损压缩算法. 该算法对图像序列第一帧采用JPEG-LS算法编码, 对帧间预测误差帧进行Golomb编码, 从而实现对连续采集到的液滴图像序列进行无损压缩. 实验结果表明, 该算法比单纯采用JPEG-LS算法的压缩率有明显提高, 编解码过程更简单, 编码需要时间更少.      

Future of Space Astronomy: A global Road Map for the next decades

The use of space techniques continues to play a key role in the advance of astrophysics by providing access to the entire electromagnetic spectrum from radio to high energy γ rays. The increasing size, complexity and cost of large space observatories places a growing emphasis on international collaboration. Furthermore, combining existing and future datasets from space and “ground based” observatories is an emerging mode of powerful and relatively inexpensive research to address problems that can only be tackled by the application of large multi-wavelength observations. While the present set of astronomical facilities is impressive and covers the entire electromagnetic spectrum, with complementary space and “ground based” telescopes, the situation in the next 10–20 years is of critical concern. The James Webb Space Telescope (JWST), to be launched not earlier than 2018, is the only approved future major space astronomy mission. Other major highly recommended space astronomy missions, such as the Wide-field Infrared Survey Telescope (WFIRST), the International X-ray Observatory (IXO), Large Interferometer Space Antenna (LISA) and the Space Infrared Telescope for Cosmology and Astrophysics (SPICA), have yet to be approved for development.     

Relativistic electron fluxes and dose rate variations during April–May 2010 geomagnetic disturbances in the R3DR data on ISS

Space radiation has been monitored successfully using the Radiation Risks Radiometer-Dosimeter (R3D) installed at the ESA EXPOSE-R (R3DR) facility outside of the Russian Zvezda module of the International Space Station (ISS) between March 2009 and January 2011. R3DR is a Liulin type spectrometer–dosimeter with a single Si PIN detector 2 cm² of area and 0.3 mm thick. The R3DR instrument accumulated about 2 million measurements of the absorbed dose rate and flux of 10 s resolution. The total external and internal shielding before the detector of R3DR device is 0.41 g cm⁻². The calculated stopping energy of normally incident particles to the detector is 0.78 MeV for electrons and 15.8 MeV for protons. After the Coronal Mass Ejection (CME) at 09:54 UTC on 3 April 2010, a shock was observed at the ACE spacecraft at 0756 UTC on 5 April, which led to a sudden impulse on Earth at 08:26 UTC. Nevertheless, while the magnetic substorms on 5 and 6 of April were moderate; the second largest in history of GOES fluence of electrons with energy >2 MeV was measured. The R3DR data show a relatively small amount of relativistic electrons on 5 April. The maximum dose rate of 2323 μGy day⁻¹ was reached on 7 April; by 9 April, a dose of 6600 μGy was accumulated. By the end of the period on 7 May 2010 a total dose of 11,587 μGy was absorbed. Our data were compared with AE-8 MIN, CRESS and ESA-SEE1 models using SPENVIS and with similar observations on American, Japanese and Russian satellites.     

空间相机热平衡试验温度预测方法改进及应用

为实现对航天器热平衡试验平衡温度的预测,建立了热平衡温度预测的方程式,对影响预测结果的各参数进行了分析。首先,由节点网络法推导出平衡温度表达式,介绍了其基于非线性最小二乘法的求解过程,建立了平衡温度的迭代方程;其次,结合大量的试验数据,对影响迭代结果的3个因素进行了统计分析,并最终确定了各因素的合理取值范围;最后,利用温度预测程序对某空间相机热平衡试验中低温工况的平衡温度进行了预测,并与试验结束后的结果进行了对比。结果表明,预测温度与试验数据的误差为±1℃（在3%之内）,满足精度要求,对热平衡温度准确的预测有效的缩短了试验时间,节省试验费用。     

抗辐射模拟CMOS集成电路研究与设计

为研究宇宙辐射环境中航天器里的模拟互补金属氧化物半导体(Complementary Metal Oxide Semiconductor,CMOS)集成电路性能和各种效应,并在辐射效应所产生机制的基础上,从设计和工艺方面提出了模拟CMOS集成电路主要抗辐射加固设计方法.在宇宙环境中,卫星中的模拟CMOS集成电路存在CMOS半导体元器件阈值电压偏离、线性跨导减小、衬底的漏电流增加和转角1/f噪声幅值增加.所以提出了3种对模拟CMOS集成电路进行抗辐射加固的方法:1)抗辐射模拟CMOS集成电路的设计;2)抗辐射集成电路版图设计;3)单晶半导体硅膜(Silicon on Insulator,SOI)抗辐射工艺与加固设计.根据上面的设计方法研制了抗辐射加固模拟CMOS集成电路,可以取得较好的抗辐射效果.     

Estimation of ballistic coefficients of low altitude debris objects from historical two line elements

This paper presents a new method for estimating ballistic coefficients (BCs) of low perigee debris objects from their historical two line elements (TLEs). The method uses the drag perturbation equation of the semi-major axis of the orbit. For an object with perigee altitude below 700 km, the variation in the mean semi-major axis derived from the TLE is mainly caused by the atmospheric drag effect, and therefore is used as the source in the estimation of the ballistic coefficient. The method is tested using the GRACE satellites, and a number of debris objects with external ballistic coefficient values, and agreements of about 10% are achieved.