统筹图中求有关参数的权关联矩阵算法

给出一个求统筹图中有关参数的数值算法，证明了算法的理论依据，并举例说明算法的应用。     

H6飞机最大起飞质量数学模型的研究

正确确定最大起飞质量，对于轰炸机和大型运输机的起飞安全有着非常重要的意义。确定最大起飞质量，以往多采用作图的方法，由于影响最大起飞质量的因素比较复杂，所以比较准确的数学模型未曾建立。近几年来对这个问题进行了多方面的探讨，得出一个计算Ｈ６最大起飞质量比较准确的数学模型。此数学模型的建立为其它轰炸机、运输机最大起飞质量的计算开辟了一条新路，对工程应用具有一定的参考价值。     

The entropy in groups – a clue to galaxy formation

The entropy in the hot X-ray gas in groups of galaxies is a fossil of the process of galaxy formation The amount of entropy in these low mass systems considerably exceeds that predicted from structure formation models. To explain these results requires “extra” energy which is a relic of the process of star formation and active galaxy heating. We present new XMM results on the entropy and entropy profiles. These results are inconsistent with pre-heating scenarios which have been developed to explain the entropy floor in groups but are broadly consistent with models of structure formation which include the effects of heating and/or the cooling of the gas. The total entropy in these systems provides a strong constraint on all models of galaxy and group formation, and on the poorly defined feedback process which controls the transformation of gas into stars and thus the formation of structure in the universe.     

温度计量技术在航空发动机试车台健康管理中的应用

分析了航空发动机试车台温度配置参数传统离线校准方法,针对其存在的反复拆装耗时长且易引发故障、缺少系统综合误差的判定方法等不足,开展发动机试车台静态状态下的整机在线校准方法研究。通过给被校准参数传感器提供标准热源的方式,开展温度传感器及温度通道（温度仪表）在线整机校准。通过对发动机试车台系统模拟仪表显示结果与标准器读数进行比较,确认在线校准的有效性,实现了试车台系统综合误差校准,为试车台健康管理提供支撑。     

中国梦:实事求是之梦

党的实事求是思想路线有着科学的内涵,在它的指导下,中国梦充满着实事求是思想,它是一种实事求是之梦。从中国梦的提出、中国梦的内涵、中国梦的依靠力量和中国梦的实现途径四个不同视角对中国梦进行解构,我们可以深刻理解其实事求是的意蕴。     

Space weather service activities and initiatives at LAMP (Argentinean Space Weather Laboratory group)

Since more than one decade ago, several institutions started to offer a large variety of Operative Space Weather (SWx) products. This is of major importance because Space Weather events can affect aviation communications, global positioning systems, grid electric power, satellite technologies, and human health in space. The scientific potential on solar-terrestrial physics in Argentina motivated the creation of an interdisciplinary Laboratory of Space Weather in Argentina. The Argentinean Space Weather Laboratory (in Spanish ‘Laboratorio Argentino de Meteorología del esPacio’, LAMP) was initiated in 2016, and it carries out daily monitoring of real-time information (space and ground-based instruments) on Space Weather. The information is synthesized on a weekly bulletin as a summary of the Space Weather conditions, and it is posted on a website (spaceweather.at.fcen.uba.ar). The analyzed information includes own data and of other centers that offer them publicly, and it is also analyzed and discussed later on, during monthly briefings. In particular, one of the regional products that is included in the briefing discussions and it was developed by LAMP in collaboration with INPE-EMBRACE, involves Vertical Total Electron Content (VTEC) maps in the Argentinean region. LAMP set up a Space Weather Laboratory in the Antarctic peninsula, in the Argentine Marambio base, where a Water Cherenkov radiation Detector (WCD) was installed during the Argentinean Antarctic campaign (January-March of 2019). This detector is the southern node of a Latin American Collaboration (LAGO, Latin American Giant Observatory), which is a network of WCDs installed throughout more than 10 Latin American countries.     

Is the Earth’s orbital motion linked to the spin rotation of the Sun?

Time variations of the magnetic field of the Sun, seen as a star (the data 1968–2018, with more than 27 thousand daily measurements of the solar mean magnetic field), allowed to specify the rotation period of the gravitating solar mass: 27.027(6)?days, synodic. This indicates a presumably unknown physical connection between motions of the Sun and the Earth: in the course of a year our star accomplishes nearly 27 half-revolutions, while the planet itself performs an identical number of its spinnings during one complete axial revolution of the Sun. True origin of this strange Sun–Earth resonance is unknown, but it is supposed the phenomenon might be caused by slight coherent perturbations of gravity within the solar system.     

Automatic detection of typical dust devils from Mars landscape images

This paper presents an improved algorithm for automatic detection of Martian dust devils that successfully extracts tiny bright dust devils and obscured large dust devils from two subtracted landscape images. These dust devils are frequently observed using visible cameras onboard landers or rovers. Nevertheless, previous research on automated detection of dust devils has not focused on these common types of dust devils, but on dust devils that appear on images to be irregularly bright and large. In this study, we detect these common dust devils automatically using two kinds of parameter sets for thresholding when binarizing subtracted images. We automatically extract dust devils from 266 images taken by the Spirit rover to evaluate our algorithm. Taking dust devils detected by visual inspection to be ground truth, the precision, recall and F-measure values are 0.77, 0.86, and 0.81, respectively.     

Beidou wide-area augmentation system clock error correction and performance verification

On December 27, 2018, the Beidou-3 System (BDS-3) has completed the deployment of 18 Medium Earth Orbit (MEO) satellites combined as a space constellation. In addition to the augmentation information for the new system signals B1C and B2a, the BDS-3 is compatible with the three augmentation information broadcast by the BDS-2 system for B1I and B3I signals: equivalent clock error correction, User Differential Ranging Error (UDRE) and Grid Ionosphere Vertical Error (GIVE). In this paper, the observation data of Beidou monitoring network are used to analyze the pseudo-range observation quality of the smooth transition signals B1I and B3I of BDS-2 and BDS-3. At the same time, the relationship between the equivalent clock error correction and the prediction error of the satellite clock is analyzed by using the Two-Way Satellite Time and Frequency Transfer (TWSTFT) data. The results show that the correlation between the equivalent clock error correction and the monitored clock error by using the TWSTFT data is greater than 60%. We calculate the UDRE by using the equivalent clock error correction. The results show that the satellite equivalent clock error correction can improve the accuracy of User Equivalent Range Error (UERE) by about 50%. This paper also compares the positioning accuracy of the BDS-2 satellites with the BDS-2 satellites combined BDS-3 satellites. The results show that the three-dimensional positioning accuracy is improved by about 30% after the BDS-3 satellites are added.     

Space Debris Mitigation in France,Germany, Italy and United Kingdom

The Space systems today provide growing benefits to enhance the quality of humankind. However, as a by-product, the orbiting objects inevitably leaves some debris which after 50 years of space activities represent a concern for all space agencies and manufacturers and operators. Since last year no international agreement was in place to mitigate the growing population of space debris objects. The successful result obtained at UN-COPUOS in 2007 and available in the OOSA web site, now gives to the public, a set of voluntary international guidelines that could, if adopted by each space fairing Country, help in maintaining the present space environment. More further steps are necessary in the future to define a legal and normative framework. The paper will present the seven established UN Space Debris guidelines as well as examples of the minimum steps to be carried out at national level to enable the UN-COPUOS to start the discussion of the legal aspect associated with the space debris issue.