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91.
This viewpoint examines the likely reasons behind the renewed focus on international cooperation in the new US National Space Policy, noting that the rise of various Asian space powers is one factor. It demonstrates the increase in US-Asian space cooperation that is already underway, arguing that such cooperation can only be to the good in providing Asian countries with a greater degree of cutting-edge technology and know-how, as well as contributing to the overall safety and security of outer space. Nevertheless, there will doubtless be problems such as cost overruns and delays and effort will have to be applied if cooperation is to work.  相似文献   
92.
The 2014 session of the Legal Subcommittee (LSC) of the United Nations Committee on the Peaceful Uses of Outer Space (UNCOPUOS) saw a particularly extensive and thorough debate on the working methods of this forum, which has the status of the highest body in space law making. By discussing the working methods it also became apparent how delegations actually regard the LSC and what expectations they have from it. In a time of considerable changes in space activities and space diplomacy alike, it was only a matter of time that such a comprehensive discussion arose. And while it did not immediately lead to decisions, it provided numerous signals for the future of the LSC.  相似文献   
93.
介绍了一种用于GPS时差比对数据处理的自适应卡尔曼滤波器,在Matlab环境下编写了离散时间形式的卡尔曼滤波算法程序,利用该算法对GPS信号与铯原子频标的时差比对数据进行了分析处理,最后介绍了该算法的数字芯片FPGA实现。  相似文献   
94.
95.
运用纵向比较分析与横向比较分析相结合的方法,从社会保障支出水平、社会保障覆盖水平和社会保障制度运行的经济效率三个方面对河南省社会保障制度的建设水平进行了综合评价研究。河南省的社会保障制度建设虽然取得了一定进步,但与全国平均水平相比,河南省的社保支出水平仍然较低,覆盖水平也很有限。努力构建适合河南省情的,覆盖城乡全体居民的多层次、多支柱的社会保障体系,是实现河南人民建设和谐社会的关键。  相似文献   
96.
A new meteor radar system was installed at the Amundsen–Scott station South Pole in 2001 to further the understanding of the dynamics of the Antarctic region. The antenna array consists of four yagis pointed along the 0°, 90°, 180°, and 270° meridians and five folded crossed dipoles arranged in a cross configuration and operating as an interferometer to provide position measurements for the detected radio meteors. The four yagis are time division multiplexed and used for both transmitting and receiving while the five folded crossed dipoles are only used for reception. The current arrangement of data acquisition (DAQ) systems at the South Pole allows the collection of meteors in a configuration similar to the previous meteor radar system that operated at the South Pole in the mid 1990s while also using an interferometer to accurately determine the meteor positions in the sky, which enables the determination of the vertical structure of the observed waves. This has been accomplished through the use of two DAQ and post-processing systems: COBRA (Colorado Obninsk radar) connected to the yagis and MEDAC (meteor echo detection and collection) connected to the folded crossed dipoles. With two separate DAQ systems operating in parallel we have the ability to directly compare the results and understand the inherent variability in the derived scientific results based on different system architectures and processing assumptions. The impact of operating a system without an interferometer on the amplitudes and phases of the observed wave components is considered. We find that the lack of altitude resolution of the COBRA DAQ system leads to an underestimation of the amplitude of the s = 1 component of the semidiurnal tide of ∼20% during the summer months.  相似文献   
97.
The CALorimetric Electron Telescope, CALET, mission is proposed for the observation of high-energy electrons and gamma-rays at the Exposed Facility of the Japanese Experiment Module on the International Space Station. The CALET has a capability to observe the electrons (without separation between e+ and e) in 1 GeV–10 TeV and the gamma-rays in 20 MeV–several TeV with a high-energy resolution of 2% at 100 GeV, a good angular resolution of 0.06 degree at 100 GeV, and a high proton-rejection power of nearly 106. The CALET has a geometrical factor of 1 m2sr, and the observation period is expected for more than three years. The very precise measurement of electrons enables us to detect a distinctive feature in the energy spectrum caused from WIMP dark matter in the Galactic halo. The excellent energy resolution of CALET, which is much better than GLAST or air Cherenkov telescopes over 10 GeV, enables us to detect gamma-ray lines in the sub-TeV region from WIMP dark matter annihilations. The CALET has, therefore, a unique capability to search for WIMP dark matter by the hybrid observations of electrons and gamma-rays.  相似文献   
98.
The microgravity environment aboard orbiting spacecraft has provided a unique laboratory to explore topics in basic plant biology as well as applied research on the use of plants in bioregenerative life support systems. Our group has utilized the European Modular Cultivation System (EMCS) aboard the International Space Station (ISS) to study plant growth, development, tropisms, and gene expression in a series of spaceflight experiments. The most current project performed on the ISS was termed Seedling Growth-1 (SG-1) which builds on the previous TROPI (for tropisms) experiments performed in 2006 and 2010. Major technical and operational changes in SG-1 (launched in March 2013) compared to the TROPI experiments include: (1) improvements in lighting conditions within the EMCS to optimize the environment for phototropism studies, (2) the use of infrared illumination to provide high-quality images of the seedlings, (3) modifications in procedures used in flight to improve the focus and overall quality of the images, and (4) changes in the atmospheric conditions in the EMCS incubator. In SG-1, a novel red-light-based phototropism in roots and hypocotyls of seedlings that was noted in TROPI was confirmed and now can be more precisely characterized based on the improvements in procedures. The lessons learned from sequential experiments in the TROPI hardware provide insights to other researchers developing space experiments in plant biology.  相似文献   
99.
One of the methods to adapt the International Reference Ionosphere model to real time conditions is to use instantaneous values of the critical frequency of the ionosphere foF2. It is shown that there can be large discrepancies between model and experimental values of the total electron content TEC after this adaptation. Improvement can be provided by the use of an empirical model of the ionospheric slab thickness τ. This conclusion is based on analysis of contributions of various correction factors connected with foF2 and τ into discrepancies between model and experimental values of TEC.  相似文献   
100.
首先介绍了排放权交易的起源、概念、经济理论和国际法基础,然后重点总结了欧盟将航空运输活动纳入排放权交易的主要内容,最后,提出了我国民航实施排放权交易需解决的关键问题。  相似文献   
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