Correlation between solar flare productivity and photospheric vector magnetic fields

Studying the statistical correlation between the solar flare productivity and photospheric magnetic fields is very important and necessary. It is helpful to set up a practical flare forecast model based on magnetic properties and improve the physical understanding of solar flare eruptions. In the previous study ([Cui, Y.M., Li, R., Zhang, L.Y., He, Y.L., Wang, H.N. Correlation between solar flare productivity and photospheric magnetic field properties 1. Maximum horizontal gradient, length of neutral line, number of singular points. Sol. Phys. 237, 45–59, 2006]; from now on we refer to this paper as ‘Paper I’), three measures of the maximum horizontal gradient, the length of the neutral line, and the number of singular points are computed from 23990 SOHO/MDI longitudinal magnetograms. The statistical relationship between the solar flare productivity and these three measures is well fitted with sigmoid functions. In the current work, the three measures of the length of strong-shear neutral line, total unsigned current, and total unsigned current helicity are computed from 1353 vector magnetograms observed at Huairou Solar Observing Station. The relationship between the solar flare productivity and the current three measures can also be well fitted with sigmoid functions. These results are expected to be beneficial to future operational flare forecasting models.     

金工实习的管理模式研究

金工实习是工科院校教学中的重要环节。为适应当前高等教育的发展和用人单位对毕业生专业素质的要求,在分析了金工实习现存的种种问题后提出了改革传统实习教学管理模式的思路和措施。     

A data transmission scheduling algorithm for rapid-response earth-observing operations

With the development of rapid-response Earth-observing techniques, the demand for reducing a requirements-tasking-effects cycle from 1 day to hours grows rapidly. For instance, a satellite user always wants to receive requested data in near real-time to support their urgent mis- sions, such as dealing with wildfires, volcanoes, flooding events, etc. In this paper, we try to reduce data transmission time for achieving this goal. The new feature of a responsive satellite is that users can receive signals from it directly. Therefore, the traditional satellite control and operational tech- niques need to be improved to accommodate these changes in user needs and technical upgrading. With that in mind, a data transmission topological model is constructed. Based on this model, we can deal with the satellite data transmission problem as a multi-constraint and multi-objective path- scheduling problem. However, there are many optional data transmission paths for each target based on this model, and the shortest path is preferred. In addition, satellites represent scarce resources that must be carefully scheduled in order to satisfy as many consumer requests as possible. To efficiently balance response time and resource utilization, a K-shortest path genetic algorithm is proposed for solving the data transmission problem. Simulations and analysis show the feasibility and the adaptability of the proposed approach.     

凝胶试验系统的设计及试后处理工艺

总结了凝胶发动机不同研制阶段相对应的试验系统以及系统试后处理工艺。包括以下几个方面:25N发动机试验系统的建立;变推力发动机试验系统的建立;双组元发动机试验系统的建立;变推力发动机试验系统的最终建立和凝胶试验系统试后处理工艺。通过对不同试验系统的建立与比较,确立了最终的凝胶试验系统及系统试后处理工艺。     

关于飞机侧风着陆问题的分析

首先，介绍了修正侧风的三种基本方法和基本原理，指出了着陆下滑阶段修正侧风应注意的问题。其次，分析了侧风对着陆拉平和平瓢阶段以及对不同机种飞机着陆滑跑方向的影响及其修正方法。再次，介绍了侧风条件下不同机种飞机减速伞的使用特点。最后，重点分析了带偏侧角接地及滑跑的成因、危害、预防措施及处理方法等。侧重于实际操纵特点的介绍与分析，对侧风着陆安全具有一定的理论指导作用。     

城市交通污染及其管理对策

城市交通污染产生的根源在于城市交通的负外部效应。为实现对城市交通污染的有效治理,对治理城市交通污染的环境管理手段作了比较与创新,得出短期内应是管制手段与征收污染税结合使用,许可证交易可作为未来的管理手段的结论。     

吊带非正常断裂的故障分析与优化措施

以某项目研制过程中,减速伞提前分离故障为切入点,探讨了吊带在非正常位置受力导致的吊带断裂问题.根据相关视频资料及落地现场的检查情况,以及采集到的测试数据,对故障机理进行了全面分析,并结合减速伞下吊带静态拉伸试验及动态冲击试验结果,借鉴国内外吊带系统的相关设计经验,提出了从工作程序、结构及强度3方面采取措施,解决吊带在非...     

资源一号02B卫星分系统问抗电磁干扰的措施

数据采集分系统上行链路在整星EMC试验中受到干扰,文章描述了为抗干扰采取的屏蔽、隔离等相关措施。结果表明：姿态与轨道控制分系统两台星敏感器对外传导发射干扰和HW数传分系统编码器对外辐射发射干扰均已减弱,并且改善了数据收集分系统工作的电磁环境,从而使其上行链路干扰从15dB减少到4dB,证实所采取的EMC抗干扰措施有效,数据收集分系统、姿态与轨道控制分系统和HW数传分系统之间是电磁兼容的。     

基于遗传算法和 Vague集的液压位置控制系统自适应 PID控制

在被控对象模型精度不高的情况下,设计了一种自适应PID控制方法,提高其鲁棒性,以确保系统的响应具有最优的动态性能和稳态性能。该方法在常规PID控制的基础上,引入智能技术,在线实时调整PID控制器的3个参数。该控制器主要由3部分构成:一是采用遗传算法优化模糊推理规则;二是精确的Vague集推理规则表;三是基于Vague集相似度量的自适应PID控制。仿真结果表明,该控制方法响应速度快,稳态精度高。     

单脊波导裂缝天线面阵的研制

分析了某机载雷达单脊波导裂缝天线面阵的结构特点和制造要点.在此基础上拟定了天线面阵精密制造流程,并阐述了其中的关键工艺措施.