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71.
地球同步轨道高压太阳电池阵充放电效应研究 总被引:4,自引:2,他引:4
地球同步轨道(GEO)高压太阳电池阵表面静电放电(ESD)引起二次放电可能导致太阳电池阵永久性短路损坏。文章主要针对GEO高压太阳电池阵充放电效应问题,重点分析了高压太阳电池阵表面ESD和二次放电产生的物理过程,并利用负高压偏置方法开展了GEO高压太阳电池阵表面ESD和二次放电地面模拟试验。试验验证了反转电位梯度电场是导致GEO高压太阳电池阵表面产生ESD的触发因素之一,同时得到了GaAs高压太阳电池阵样品表面产生ESD和二次放电的电压阈值。 相似文献
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75.
宫自强 《北华航天工业学院学报》2013,23(1):10-14
本文探讨如何通过地源热泵技术实现建筑节能。研究通过地源热泵来实现一机多用,使其既能用于冬季供暖,又可以用于夏季制冷。同时也讨论了如何与太阳能相配合,来实现地热平衡。文中还给出了通过插值法和曲线拟合法对测量数据进行处理获得变温带和增温带的温度-深度曲线的方法。 相似文献
76.
Status of solar sail technology within NASA 总被引:2,自引:0,他引:2
Les Johnson Roy YoungEdward Montgomery Dean Alhorn 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
In the early 2000s, NASA made substantial progress in the development of solar sail propulsion systems for use in robotic science and exploration of the solar system. Two different 20-m solar sail systems were produced. NASA has successfully completed functional vacuum testing in their Glenn Research Center’s Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by Alliant Techsystems Space Systems and L’Garde, respectively. The sail systems consist of a central structure with four deployable booms that support each sail. These sail designs are robust enough for deployment in a one-atmosphere, one-gravity environment and are scalable to much larger solar sails – perhaps as large as 150 m on a side. Computation modeling and analytical simulations were performed in order to assess the scalability of the technology to the larger sizes that are required to implement the first generation of missions using solar sails. Furthermore, life and space environmental effects testing of sail and component materials was also conducted. 相似文献
77.
C. P. T. Groth D. L. De Zeeuw T. I. Gombosi K. G. Powell 《Space Science Reviews》1999,87(1-2):193-198
A parallel adaptive mesh refinement (AMR) scheme is described for solving the governing equations of ideal magnetohydrodynamics
(MHD) in three space dimensions. This solution algorithm makes use of modern finite-volume numerical methodology to provide
a combination of high solution accuracy and computational robustness. Efficient and scalable implementations of the method
have been developed for massively parallel computer architectures and high performance achieved. Numerical results are discussed
for a simplified model of the initiation and evolution of coronal mass ejections (CMEs) in the inner heliosphere. The results
demonstrate the potential of this numerical tool for enhancing our understanding of coronal and solar wind plasma processes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
78.
Hardi Peter 《Space Science Reviews》1998,85(1-2):253-260
Ionization-diffusion mechanisms to understand the first ionization potential (FIP) fractionation as observed in the solar
corona and the solar wind are reviewed. The enrichment of the low-FIP elements (<10 eV) compared to the high-FIP elements,
seen in e.g. slow and fast wind or polar plumes, is explained. The behaviour of the heavy noble gases becomes understandable.
The absolute fractionation, i.e. in relation to hydrogen, can be calculated and fits well to the measurements. The theoretical
velocity-dependence of the fractionation will with used to determine the velocities of the solar wind in the chromosphere.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
79.
M. Gabriel 《Space Science Reviews》1998,85(1-2):113-116
We show that to explain the opposite line asymmetries shown by the velocity and intensity spectra, it is necessary to solve
the full non-adiabatic problem which is at least of the fourth order.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
80.
A.A. Hady 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
The space science research has been started in Egypt since 1910 by measuring the solar constant as indication of solar radiation at Helwan Observatory. The solar sunspot studies and its influence on the Nile flooding was erected and operated at Helwan as a first solar station in Egypt during 1957. Zeiss-Coude’ refractor was installed in 1964. Astronomy and space science educations started in Egypt at the university level since 1936 at Department of Astronomy and Meteorology of Cairo University. Undergraduate and graduate education in Egypt will be discussed in this work. 相似文献