我国电离层基本参量与国际参考模式的比较

本文利用我国满洲里、北京、武昌、重庆和广州等台站电离层观测记录,对各层临界频率的实测值(月中值)与IRI-86的计算值进行了分析比较.|发现两者存在着显著而系统的偏离.E层和F₁层偏离较小F₂层偏离较大,其相对值有时超过60%.总的来说,f₀F₂的相对偏离:夜间大,白天小冬季大,夏季小太阳活动低年大,高年小随着纬度降低偏离增大模式值普遍大于实测值.      

中国卫星电视教育的崛起和发展趋势

对中国开展广播电视教育的历史进行了回顾,较详细的叙述了卫星电视教育的崛起。在总结经验的基础上,又突出论述了今后要努力提高效益和精心制作电视教育节目两个关键性问题。文中根据资料引入了大量数据佐证文章的论点。     

基于陆态网的区域电离层TEC空间变化特性分析

为研究中国陆态网区域电离层TEC在空间小尺度、高分辨率情况下的变化特性及适用精度范围，利用陆态网260个GNSS连续运行观测站数据，解算并生成2016-2017年731天陆态网区域电离层RIM格网，并进行精度验证.在同一RIM格网中，分别在经度和纬度方向上对间隔不同经纬度的TEC格网点作差分析.结果表明:陆态网区域内经度方向上TEC最大变化率和平均变化率分别为0.30TECU·（°）-1和0.11TECU·（°）-1；经度间隔1°时，TEC差值小于2TECU，且随着经度间隔的增大，其TEC差值也随之增大，并表现出一定的半年和周年变化规律；纬度方向上TEC最大变化率和平均变化率分别为1.7TECU·（°）-1和0.46TECU·（°）-1；陆态网区域内电离层TEC随纬度减小而增大，纬度间隔1°时，99.4%的TEC差值小于4TECU，且随着纬度间隔的增大，其TEC差值也随之增大，并表现出一定的半年和周年变化规律；间隔相同情况下，纬度方向上TEC的变化比经度方向上大.      

Analysis of spatiotemporal trajectories for stops along taxi paths

Stops along taxi trajectories, such as picking up and dropping off passengers, are spatially clustered and related to certain attributes of places where stops are made. To detect the hidden knowledge regarding these places, this article examines the semantics of massive taxi stops in a large city. Each taxi trajectory is modeled as a series of sequential semantic stops labeled by street names. All the trajectories can be examined as a document corpus, from which the hidden themes of the stops are identified through Latent Dirichlet Allocation model. Conventional GIS tools are coupled with topic modeling toolkit to visualize and analyze potential information of stop topics for understanding intra-city dynamics. The effectiveness of this approach is illustrated by a case study using a large dataset of taxi trajectories including approximately 4,000 taxis in Wuhan, China.     

Crustal deformation characteristics of Sichuan-Yunnan region in China on the constraint of multi-periods of GPS velocity fields

In order to obtain deformation parameters in each block of Sichuan-Yunnan Region (SYG) in China by stages and establish a dynamic model about the variation of the strain rate fields and the surface expansion in this area, we taken the Global Positioning System (GPS) sites velocity in the region as constrained condition and taken advantage of the block strain calculation model based on spherical surface. We also analyzed the deformation of the active blocks in the whole SYG before and after the Wenchuan earthquake, and analyzed the deformation of active blocks near the epicenter of the Wenchuan earthquake in detail. The results show that, (1) Under the effects of the carving from India plate and the crimping from the potential energy of Tibetan Plateau for a long time, there is a certain periodicity in crustal deformation in SYG. And the period change and the earthquake occurrence have a good agreement. (2) The differences in GPS velocity fields relative Eurasian reference frame shows that the Wenchuan earthquake and the Ya'an earthquake mainly affect the crustal movement in the central and southern part of SYG, and the average velocity difference is about 4–8?mm/a for the Wenchuan earthquake and 2–4?mm/a for the Ya'an earthquake. (3) For the Wenchuan earthquake, the average strain changed from 10 to 20 nanostrian/a before earthquake to 40–50 nanostrian/a after the earthquake, but before and after the Ya’an earthquake, the strain value increased from about 15 nanostrian/a to about 30 nanostrian/a. (4) The Wenchuan earthquake has changed the strain parameter of each active block more or less. Especially, the Longmen block and Chengdu block near the epicenter. The research provides fundamental material for the study of the dynamic mechanism of the push extrusion from the north-east of the India plate and the crimp from Qinghai Tibet Plateau, and it also provides support for the study of crustal stress variation and earthquake prediction in Sichuan Yunnan region.     

某型分系统电磁兼容优化设计

以某型分系统研制过程中的电磁兼容设计为例，结合实际需求，提出了系统电磁兼容设计过程中干扰 源抑制和传播路径的优化设计方法，实现了从分系统电磁干扰源、耦合路径、信号完整性和结构搭接屏蔽的电 磁兼容优化设计，为系统电磁兼容设计提供了思路，具有重要借鉴意义。     

创新资本、经济危机与产业演进

产业演进表现为朝阳产业对夕阳产业的不断替代,当夕阳产业利润率日益趋薄,资本积累呈现出垄断、虚拟、全球化和创新四种模式趋势,其中,前三种不包含产业升级,最终将导致经济危机,只有创新模式能够带来产业升级,引领经济走出危机。在危机中,必须调整产业结构,培育朝阳产业,同时,在人才、资金等方面为创新资本的运作创造良好条件。     

Agronomy in space – China’s crop breeding program

Using the US-coined concept of space industrialization and reflecting the ongoing creation of a space economy, this paper maintains that China’s 20-odd years of practice and achievement in crop breeding in space should be seen as an integral part of any space economy. The paper analyzes the Chinese government’s space breeding policies, its support for it via financial allocation, and the relevant programs, and highlights the key achievements so far achieved in the sector. In conclusion, it outlines the main hurdles to crop breeding in space but looks forward to a bright future for this activity.     

飞院历史发展与文化积淀研究

中国民航飞行学院历经54年,现已成为亚洲最大、世界知名的民航飞行院校,获得了中国民航飞行员"摇篮"及中国民航干部"黄埔"的美誉。回顾历史,飞院经历了初创时期、"文化大革命"时期、恢复时期、快速发展时期以及现在的综合发展、全面提升五个时期,不同时期具有不同的文化特点。飞院的历史也正是一部飞院文化发展史。不同时期的飞院文化经过一代又一代飞院人的传承,最终积淀成现在特有的飞院文化,即高等教育文化、飞行文化、安全文化及准军事管理文化。     

加快中部地区对外开放的思考

对外开放是促进中部崛起的引擎.20世纪90年代以来,中部地区对外贸易快速增长,利用外资水平不断提高,对外经贸工作进展明显,投资环境得到改善,但还存在着开放度低、利用外资规模较小等问题.在对当前面临的开放环境与条件分析的基础上,提出了加快中部地区对外开放的对策建议.