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71.
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
72.
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
73.
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
74.
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
75.
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
76.
T.P. Dachev B. Tomov Yu. Matviichuk Pl. Dimitrov N. Bankov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The paper presents observation of relativistic electrons. Data are collected by the Radiation Risk Radiometer-Dosimeters (R3D) B2/B3 modifications during the flights of Foton M2/M3 satellites in 2005 and 2007 as well as by the R3DE instrument at the European Technology Exposure Facility (EuTEF) on the Columbus External Payload Adaptor at the International Space Station (ISS) in the period February 20 – April 28, 2008. On the Foton M2/M3 satellites relativistic electrons are observed more frequently than on the ISS because of higher (62.8°) inclination of the orbit. At both Foton satellites the usual duration of the observations are a few minutes long. On the ISS the duration usually is about 1 min or less. The places of observations of high doses due to relativistic electrons are distributed mainly at latitudes above 50° geographic latitude in both hemispheres on Foton M2/M3 satellites. A very high maximum is found in the southern hemisphere at longitudinal range 0°–60°E. At the ISS the maximums are observed between 45° and 52° geographic latitude in both hemispheres mainly at longitudes equatorward from the magnetic poles. The measured absolute maximums of dose rates generated by relativistic electrons are found to be as follows: 304 μGy h−1 behind 1.75 g cm−2 shielding at Foton M2, 2314 μGy h−1 behind 0.71 g cm−2 shielding at Foton M3 and 19,195 μGy h−1 (Flux is 8363 cm−2 s−1) behind les than 0.4 g cm−2 shielding at ISS. 相似文献
77.
综述了当前国际空间太阳能电站技术的研究进展与发展趋势。重点介绍了空间太阳能电站系统方案新构思“太阳塔”和“太阳盘”的特点;介绍了空间太阳能电站的主要相关技术———无线电能传输技术、太阳能转换技术和空间运输技术等的发展趋势;最后简要介绍了月球电站的进展情况。 相似文献
78.
79.
长期受粒子辐照、紫外辐照等因素的影响,地球同步卫星的太阳电池阵输出功率会出现较为明显的衰减。这里选取某地球同步卫星使用的背表面反射(BSR)硅太阳电池阵为研究对象,采用光强因子和温度因子修正太阳电池阵的输出功率,使用局部加权回归散点平滑法(LOWESS)分析了其在设计寿命期间的输出功率衰减规律;同时基于LOWESS建立了预测模型,用于硅太阳电池阵超寿运行期间的功率预测。实测数据表明:本文构建的预测模型可以满足超寿地球同步卫星在轨管理使用需求。 相似文献
80.
Singular formalism and admissible control of spacecraft with rotating flexible solar array 总被引:1,自引:0,他引:1
This paper is concerned with the attitude control of a three-axis-stabilized spacecraft which consists of a central rigid body and a flexible sun-tracking solar array driven by a solar array drive assembly. Based on the linearization of the dynamics of the spacecraft and the modal identi- ties about the flexible and rigid coupling matrices, the spacecraft attitude dynamics is reduced to a formally singular system with periodically varying parameters, which is quite different from a space- craft with fixed appendages. In the framework of the singular control theory, the regularity and impulse-freeness of the singular system is analyzed and then admissible attitude controllers are designed by Lyapunov's method. To improve the robustness against system uncertainties, an H∞ optimal control is designed by optimizing the H∞ norm of the system transfer function matrix. Comparative numerical experiments are performed to verify the theoretical results. 相似文献