关于用近地卫星校准无线电外测设备的数据分析研究

1957年,东靶场首先提出了用近地卫星来校准导弹无线电外测系统的设想。这种方法的主要优点来自下述两个方面:①合作卫星处于自由下落状态,因此具有“平滑”的可预测的轨道;②卫星处于足够的高度,可由许多站进行重迭跟踪。1964年中期,这一计划终于作为一项专款项目来实施。在制定这一计划时,必须详细研究一下东靶场准备用于C波段和连续波雷达的飞行试验事后分析和处理的方法。第一步工作是作出完整的系统模型并尽量找出重要的误差源。找出了11种可能的误差源。对每一误差源开展了具体研究。有些作了深入的研究,有些仅仅浏览了有关文献,选择了校准工作所用的最理想的模型或方法。东靶场主要在下列几方面作了工作:①外测设备测量值及其误差的特性鉴定;②数据压缩和选择;③计算机程序鉴定;④卫星数据最佳区间的选择;⑤站址大地测量。最后将各项研究汇总起来形成初步处理校准卫星数据指导思想的雏型。本文扼要介绍这些研究结果以及初步处理校准卫星数据所得的某些结果。     

Adaptive sensitive frequency band selection for VMD to identify defective components of an axial piston pump

The underlying study investigates single valued neutrosophic entropy based adaptive sensitive frequency band selection for variational mode decomposition(VMD) for the purpose of identifying defective components in an axial pump. The proposed methodology is applied in the following steps. First, VMD is applied for decomposing vibration signals into various frequency bands, called as modes. After computing energy of each VMD, the lower(minimum) and upper(maximum) bounds from these energy readings ...     

海南地区强磁暴期间强区域扩展F事件研究

利用2004年海南DPS-4数字测高仪观测到的强区域扩展F(SSF)数据,分析研究了5个强磁暴(Dst＜-100 nT)事件期间海南SSF的响应特征.结果发现,在海南地区,5个强磁暴事件中有3个磁暴Dst最小值位于2200-0200 LT之间,在磁暴主相及恢复相初期均出现了SSF现象,这种触发作用可能源于磁层直接渗透电场的作用,而另两个磁暴Dst最小值均发生在白天,一个SSF现象出现在磁暴的恢复相晚间,另一个SSF现象出现在超强磁暴的初相晚间,后者可能由该超强磁暴的急始造成的直接渗透电场所触发;5个强磁暴期间发生的SSF现象或者仅出现在午夜前,或者先出现在午夜前并持续到午夜后;同时,还就这些观测结果与Dabas等人有关磁暴对ESF影响的结论进行对比和讨论.     

From the Solar Wind to the Magnetospheric Substorm

This paper gives a brief outline of the progression from the first substorm model developed in Ref.[4] and
[8] based on Kennel's ideas[3], to the present views about the mechanism by which solar wind kinetic energy is converted to electromagnetic energy at the Bow Shock and by which this energy is transferred to the magnetosphere in the form of current; about the transformation of the energy of this current to gas kinetic energy of convecting plasma tubes, and, finally, the back transformation of gas kinetic energy to electromagnetic energy in secondary magnetospheric MHD generators. The questions of the formation of the magnetospheric convection system, the nature of substorm break-up, and of the matching of currents in the magnetosphere-ionosphere system are discussed.