Flight safety implications of the extreme solar proton event of 23 February 1956

There is considerable speculation about the effects at aircraft altitudes resulting from extreme solar proton events. The ground level event (GLE) of 23 February 1956 (GLE 5), remains the largest solar proton event of the neutron monitor era in terms of its influence on count rates at monitors near sea level. During this GLE the count rate was increased by as much as 4760% (15-min average) at the Leeds monitor relative to the count rate from galactic cosmic radiation (GCR). Two modern models of the event cumulative solar proton spectrum for this event, a 6-parameter fit in energy and a 4-parameter Band fit in rigidity, are compared with 1-h of GCR at solar minimum. While effective doses calculated with CARI-7A for both models at low geomagnetic cutoff rigidities are indeed high when compared with GCR and can exceed recommended exposure limits, both GLE spectra exhibit a much stronger dependence on cutoff rigidity than GCR, and a larger fraction of the dose from neutrons. At locations with cutoff rigidities above 4.2 and 6.4?GV, respectively, the GLE effective doses are smaller than the GCR hourly dose. At locations with cutoff rigidities above about 4?GV, GCR was the dominant source of exposure in 10?h or less at all altitudes examined. This suggests that if a similar event occurs in the future, low- and mid-latitude flights at modern jet flight altitudes could be well-protected by Earth’s magnetic field.     

Spectra of the two official GLEs of solar cycle 24

Based on ground-level data and on satellite data we determine in this work the observational spectrum of both, the Ground Level Enhancement of May 17, (2012) the so-called GLE71 and the Ground Level Enhancement of September 10, 2017 (GLE 72). We describe a simplified method to obtain the experimental spectrum at ground level. Data of the GLE71 and GLE72 indicate the presence of two different populations, each one with a different energy spectrum. On the other hand, we explore the kind of phenomena that take place at the source in these two particular events. In contrast with other methods based on the temporal synchronization between electromagnetic emissions of flares and coronal mass ejections (CME), here we develop an alternative option based on the study of the accelerated particles, by adjusting our theoretical spectra to the observational spectra. The main results of this work are the derivation of the source and acceleration parameters involved in the generation process. These results lead us to construct possible scenarios of particle generation in the source for each one of the two studied GLEs.     

硬着陆判断标准浅析

硬着陆的判断标准在业内一直以来都存在争议，本文结合实际疑似硬着陆事件，从飞机维修角度对飞机制造厂家以及报文规范制定厂家的标准进行分析，提出相对合理的维修建议。     

人机协作标准及应用动态研究

通过对人机协作内涵定义以及人机协作安全标准的叙述,提出了人机协作需要攻克的几项关键技术,点评了4款著名协作型机器人的功能,介绍了国外协作性机器人在飞机装配中的最新研究成果,最后对人与机器人协作将成为装配系统的新常态进行了展望.     

基于RBF网络的跟踪特性角对接收信号影响模型研究

在航天发射任务中,地面遥外测设备跟踪特性角（α角、β角）对接收信号质量的影响非常大,由于α角、β角影响接收信号的机理非常复杂,一直以来只进行定性分析.在研究RBF（Rradial Basis Function,径向基函数）网络的基础上,利用RBF网络建立跟踪α角、β角对接收信号的影响模型,并用已知样本数据对模型进行训练和验证,详细论证模型参数的选取方法,给出跟踪特性角对接收电平影响的量化分析和预测的一种方法.利用模型对某次发射任务设备的接收电平进行了预测,预测结果与实测结果基本相符,满足应用要求,对提高航天发射任务地面测控系统风险评估能力有重要意义.     

飞机机电系统PHM的综合诊断推理机设计

在分析区域级PHM功能及区域管理器结构的基础上,开展了综合诊断推理机设计基础准备工作,包括机电系统功能建模、aFMECA分析、机电系统关联分析。最终,设计出飞机机电系统PHM综合诊断推理机的结构及其工作流程。所设计的综合诊断推理机综合了以往多种推理机的推理机制,更加系统全面地实现了对飞机机电系统的综合诊断功能,具有一定的工程应用价值。     

Minimum time span of TOPEX/Poseidon,Jason-1 and Jason-2 global altimeter data to detect a significant trend and acceleration in sea level change

The present study aims to estimate a minimum time span of the global mean sea level time series (from TOPEX/Poseidon, Jason-1 and Jason-2 satellite altimetry) which is sufficient to detect a statistically meaningful trend in global sea level variation. In addition, the objective of this paper is also to seek a minimum time span required to detect a significant acceleration in sea level change.     

Monitoring coastal sea level using reflected GNSS signals

A continuous monitoring of coastal sea level changes is important for human society since it is predicted that up to 332 million people in coastal and low-lying areas will be directly affected by flooding from sea level rise by the end of the 21st century. The traditional way to observe sea level is using tide gauges that give measurements relative to the Earth’s crust. However, in order to improve the understanding of the sea level change processes it is necessary to separate the measurements into land surface height changes and sea surface height changes. These measurements should then be relative to a global reference frame. This can be done with satellite techniques, and thus a GNSS-based tide gauge is proposed. The GNSS-based tide gauge makes use of both GNSS signals that are directly received and GNSS signals that are reflected from the sea surface. An experimental installation at the Onsala Space Observatory (OSO) shows that the reflected GNSS signals have only about 3 dB less signal-to-noise-ratio than the directly received GNSS signals. Furthermore, a comparison of local sea level observations from the GNSS-based tide gauge with two stilling well gauges, located approximately 18 and 33 km away from OSO, gives a pairwise root-mean-square agreement on the order of 4 cm. This indicates that the GNSS-based tide gauge gives valuable results for sea level monitoring.     

对TCAS的原理分析

本文基于对防撞基本概念的理解，分析了ＴＣＡＳ工作原理，并结合实际工作过程进行了论证。     

威胁级别判断技术的研究

介绍了影响威胁级别的各种因素及威胁级别的计算模型，提出了基于非线性结构的威胁因素对威胁级别的树形权值分配法，给出了各威胁因素隶属度的确定方法。此外，还以某型地空导弹为例，介绍了突防航迹的威胁总量以及速度因素对威胁级别的影响，为进一步开展飞机航迹规划和任务规划研究提供了参考。