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841.
Space law education has an essential role in the space capacity building of a country because of its importance for human resources development in space law. Comparisons between Canada and China, the European Union and China and the United States of America (USA) and China in space law degree education, course, teaching methodology, institute and practice and communication platform are provided in an attempt to review some issues which exist within the Chinese space law educational system and to seek a better choice for China’s space law education reform. Chinese space law education has achieved noticeable progress over the past two decades. However, it is still limited in comparison to its counterparts in Europe and Northern America. The range of the space law degree education programmes and space-law-related courses is comparatively limited. A gap remains between space law education and practice in China. Chinese space law classes are still dominated by the teacher-centred teaching methodology, although several universities have some new teaching practices. The establishment of seven space law-related research institutes plays an increasingly important role in Chinese space law education, space law and policy research and legal advisory services for the Chinese government and non-governmental sectors. However, these institutes still have a long way to go in comparison with their counterparts in Europe and Northern America. While China has established domestic research platforms for space law communication through international cooperation, it does not provide space law practice platforms for space law education. While international space law does not provide a direct legal foundation for space law education in China, Chinese educational laws can lay a profound legal foundation for Chinese space law education. To promote its national expertise and capacity in space law, based on the three-pillar model and the experiences of its counterparts in North America and Europe, China should adopt a systematic and sustainable regime for its space law education.  相似文献   
842.
The European Stratospheric Balloon Observatory (ESBO) initiative aims at simplifying the access to stratospheric balloon missions. We plan to provide platforms and support with instrument design in order to support scientists. During the design process, the inevitable question of qualification for the harsh flight conditions arises. Unfortunately, there is no existing standard for qualification of stratospheric ballooning hardware. Thus, we developed a qualification procedure for use within ESBO and similar projects.In this paper, we present our analysis of the environmental conditions in the stratosphere. While conditions at typical balloon float altitudes are similar to the space environment, there are also some relevant differences. For example, the thermal environment is dominated by radiation and thermal conduction, but the remaining atmosphere still supports a certain amount of convection. The remaining atmospheric pressure in the stratosphere also leads to reduced arcing distances. Vibrational loads are far less than for space missions, but quasi-static or shock loads may occur. The criticality of radiation increases with mission duration.Based on the environmental conditions, we present the qualification procedures for ESBO, which are based on the European Cooperation for Space Standardization (ECSS) standards for space systems. Overtesting against too high requirements leads to overengineering, driving mission cost and mitigating the advantages of balloons over space missions. Therefore, we modified the ECSS standards to fit typical scientific ballooning missions over several days at altitudes up to 40 km. Furthermore, we analyzed design rules for space systems with regard to their relevance for scientific ballooning, including material and component selection. We present the experience from the hardware qualification process for the ESBO prototype STUDIO (Stratospheric UV Demonstrator of an Imaging Observatory). Even though boundary conditions are different for each individual mission, we aimed for a broader approach: We investigated more general requirements for scientific ballooning missions to support future flights.  相似文献   
843.
将全面质量管理的过程决策程序图法(PDPC)与决策分析技术的期望值法(EMV)有机结合,构建了PDPC-EMV理论模型,并将该模型引入到武器装备研制方案的设计环节中,用风险评估的思维解决全面质量管理的问题,为武器装备研制方案的设计工作开辟了一种先期质量控制思路。  相似文献   
844.
近年来,无人机运输业迅猛发展,其飞行过程中的冲突探测与避撞问题成为亟需解决的关键问题。在无人机周围建立合理的三维空间模型,优化包括紧急避撞区域、一般避撞区域、监视及提前避撞区域的三级避撞区域系统,并利用ADS-B 报文提供的无人机位置、速度等信息,基于无人机一般二维平面上的冲突探测与避撞算法,通过增加垂直方向上的冲突识别来改进冲突探测算法,对比调速、调向两种避让方案在各避撞区域的成功率。结果表明:改进算法能在无人机数量大幅增加的情况下有效识别冲突无人机,同时采用先调速后调向的避让方案,避撞成功率达到99.75%,可为保障无人机的飞行安全提供有效策略。  相似文献   
845.
A 类性能是运输类直升机的典型特征,A 类性能飞行试验是表明符合性的最佳途径。以CAAC 颁布的相关A 类性能适航文件为基础,分析A 类起飞性能产生的背景,研究相关规章条款的要求和符合性方法,探讨极限高度—速度包线、A 类起飞航迹、A 类继续起飞和中断起飞以及最终起飞决断点确认等试飞技术,制定无障碍机场A 类性能起飞决断点试飞风险管控措施。构建的直升机无障碍机场A 类性能起飞决断点试飞方法及试飞风险管控措施,有效地指导完成了AC312E、AC313 等直升机的局方审定飞行试验工作,为其获得CAAC 型号合格证奠定了基础。  相似文献   
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