Analysis of characteristic of aurora substorm observed at Antarctic Zhongshan station

The characteristics of a strong aurora substorm observed at Antarctic Zhongshan station (magnetic latitude=74.5°) on 8 April, 1999, were discussed and analyzed. The developing steps of the aurora substorm that happened in dusk time were almost the same with that of midnight aurora substorm. The averaged moving speed of the aurora arc toward pole area during the substorm expansion phase was about 3.0 km/s, westward-traveling surge speed was about 2.0 km/s. The extension from south to north in the substorm can cover 1100 km in distance. Foundation item: Supported by the National Natural Science Foundation of China (49634160) Biography: Ai Young (1958-), male, Associate professor, research direction: upper atmosphere physics.     

高铁进出站控制系统的Petri网故障诊断研究

高铁进出站控制系统是保证高铁正常运行的关键枢纽。针对高铁进出站控制系统是否发生故障及故障发生的准确位置,基于部分可观Petri网的结构特点和整数线性规划问题,提出了一种在线故障诊断算法。算法获取被诊断系统的基本观测序列和基本点火序列,计算观测序列的最大长度,选取故障诊断参数K,应用提出的故障诊断算法对高铁进出站控制系统进行仿真实验并进行了故障诊断分析。实验结果指出高铁进出站控制系统在运行过程中出现的故障,与实验设定故障完全相符。而对于系统中不可观事件和不可观运行状态所发生的故障,该算法仍准确指出了故障发生位置,由此可证明该诊断方法能够满足高铁进出站控制系统对故障诊断算法实时、准确的要求。     

南极研究及其趋势展望

在扼要阐述美国、英国、澳大利亚、新西兰四国南极科学研究战略的基础上,分析其共性、趋势和特点,并给出南极科学研究委员会(Scientific Committee on Antarctic Research, SCAR)在国际南极研究合作中发挥的作用,从而得出对南极科研战略的基本认识.     

Antarctic accumulation seasonality

The resemblance of the orbitally filtered isotope signal from the past 340 kyr in Antarctic ice cores to Northern Hemisphere summer insolation intensity has been used to suggest that the northern hemisphere may drive orbital-scale global climate changes. A recent Letter by Laepple et al. suggests that, contrary to this interpretation, this semblance may instead be explained by weighting the orbitally controlled Antarctic seasonal insolation cycle with a static (present-day) estimate of the seasonal cycle of accumulation. We suggest, however, that both time variability in accumulation seasonality and alternative stable seasonality can markedly alter the weighted insolation signal. This indicates that, if the last 340 kyr of Antarctic accumulation has not always looked like the estimate of precipitation and accumulation seasonality made by Laepple et al., this particular accumulation weighting explanation of the Antarctic orbital-scale isotopic signal might not be robust.     

借助参数编程消除导轨垂直度误差对孔位精度的影响

测算出数控机床X、Y坐标轴导轨间不垂直的角度误差，借助参数编程，在孔位坐标值中补偿一误差值，可显著提高孔的位置精度。     

俄罗斯在塞尔维亚的战略布局与俄塞关系

2006年6月5日,塞尔维亚宣布继承塞黑的国际法主体地位,6月11日,俄罗斯外交部正式承认塞尔维亚的国际法主体地位,俄塞关系进入新的历史阶段。2006—2018年俄塞关系可以分为三个阶段:2006—2008年为适应调整期;2009—2012年为平稳发展期;2013—2018年为快速发展期。从政治、经济、军事领域分析2006年以来的俄塞关系有助于其更好的合作。