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591.
C. Ferrari F. Govoni S. Schindler A. M. Bykov Y. Rephaeli 《Space Science Reviews》2008,134(1-4):93-118
We review observations of extended regions of radio emission in clusters; these include diffuse emission in ‘relics’, and
the large central regions commonly referred to as ‘halos’. The spectral observations, as well as Faraday rotation measurements
of background and cluster radio sources, provide the main evidence for large-scale intracluster magnetic fields and significant
densities of relativistic electrons. Implications from these observations on acceleration mechanisms of these electrons are
reviewed, including turbulent and shock acceleration, and also the origin of some of the electrons in collisions of relativistic
protons by ambient protons in the (thermal) gas. Improved knowledge of non-thermal phenomena in clusters requires more extensive
and detailed radio measurements; we briefly review prospects for future observations. 相似文献
592.
Y. Kamide 《Space Science Reviews》1999,90(3-4):523-523
593.
T. Sato K. Niita V. A. Shurshakov E. N. Yarmanova I. V. Nikolaev H. Iwase L. Sihver D. Mancusi A. Endo N. Matsuda Y. Iwamoto H. Nakashima Y. Sakamoto H. Yasuda M. Takada T. Nakamura 《Cosmic Research》2011,49(4):319-324
The dose reduction rates brought about by the installation of additional water shielding in a spacecraft are calculated in the paper using the particles and heavy ion transport code system PHITS, which can deal with transport of all kinds of hadrons and heavy ions with energies up to 100 GeV/n in three-dimensional phase spaces. In the PHITS simulation, an imaginary spacecraft was irradiated isotropically by cosmic rays with charges up to 28 and energies up to 100 GeV/n, and the dose reduction rates due to water shielding were evaluated for 5 types of doses: the dose equivalents obtained from the LET and linear energy spectra, the dose equivalents to skin and red bone marrow, and the effective dose equivalent. The results of the simulation indicate that the dose reduction rates differ according to the type of dose evaluated. For example, 5 g/cm2 water shielding reduces the effective dose equivalent and the LET dose equivalent by approximately 14% and 32%, respectively. Such degrees of dose reduction can be regarded to make water shielding worth the efforts required to install it. 相似文献
594.
C. Xiong H. Lühr S.Y. Ma 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
We compare electron density predictions of the International Reference Ionosphere (IRI-2007) model with in situ measurements of the satellites CHAMP and GRACE for the years from 2005 to 2010 over the subauroral regions. The electron density between 58° and 68° Mlat are considered. The trough region Ne peaks during local summers and attain the valley during local winter. Around −100°E and 60°E, two larger electron density sectors features can be seen in both hemispheres during all three seasons, which attributed to the electron extending from middle latitude to trough region. From 2005 to the beginning of 2010, the model overestimates the trough region Ne by 20% on average and the decrease of Ne in this region can also be seen during the last solar minimum. In the southern hemisphere, the model prediction shows quite well consistence with the observation during all three seasons while the huge difference between observations and model estimation implies that the IRI-2007 model needs significant improvement to predict better the trough region in northern hemisphere. 相似文献
595.
K. Enya T. Kotani K. Haze K. Aono T. Nakagawa H. Matsuhara H. Kataza T. Wada M. Kawada K. Fujiwara M. Mita S. Takeuchi K. Komatsu S. Sakai H. Uchida S. Mitani T. Yamawaki T. Miyata S. Sako T. Nakamura K. Asano T. Yamashita N. Narita T. Matsuo M. Tamura J. Nishikawa E. Kokubo Y. Hayano S. Oya M. Fukagawa H. Shibai N. Baba N. Murakami Y. Itoh M. Honda B. Okamoto S. Ida M. Takami L. Abe O. Guyon P. Bierden T. Yamamuro 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
596.
C. Shi Y. Lou H. Zhang Q. Zhao J. Geng R. Wang R. Fang J. Liu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
High-rate GPS positioning has been recognized as a powerful tool in estimating epoch-wise station displacement which is particularly useful for seismology. In this study, station displacements during the 12 May 2008 Mw 8.0 Wenchuan earthquake are derived from the 1-Hz GPS data collected at a set of stations in China. The impacts of integer ambiguity resolution and station environment-dependent effects are investigated in order to yield more accurate results. The position accuracy of horizontal components of better than 1 cm suggests that GPS can sense the rapid position oscillation of about 2 cm in amplitude. Temporal and spatial analysis is applied to the surface displacement at station XANY and the characteristics of the movements due to Rayleigh and Love waves are detected and discussed. The comparison of GPS-derived displacement with relevant synthetic data computed based on a recently published rapture model shows a reasonable agreement in waveform. The various differences in amplitude need further investigation and also imply that rapture inversion might be improved if GPS-derived displacement is assimilated. 相似文献
597.
Y. Liu X.X. Pan G.H. Li X. Liu L.X. Jiang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
Based on the Monte Carlo ray-tracing method, the network coefficients of thermal network model describing the radiation heat transfer among satellite surfaces is solved by considering the surface material optical characters. It is superiority to the conventional Gebhart’s method in view of the grey body and the diffuse reflection assumptions. The zone leveling method is used to discrete the governing equations and the solar absorpivity is separated and considered to be an important correction parameter. Effects of the solar incidence round angle, the zenith angle and the ratio of absorpivity to emissivity (RAE) on temperature distribution are numerically simulated and discussed in detail. The higher or the lower the RAE may be lead to the alternative heating and cooling tend with a larger heating or cooling velocity of main body surfaces than the solar array surfaces. Furthermore, maximum temperature of main body is almost larger than solar arrays. Under the same RAE, solar incidence angle make a great effect on the uniform character of temperature distribution. 相似文献
598.
G.Y.Smolkov 《空间科学学报》2005,25(5):345-350
Presented are the ideas and proposals in regards to the pooling of by RAS, SB, ISTP, and CSSAR,CAS toward coordinated usage of existing ground-based and orbiting helio-geophysical observatories, single large installations as well as creating, forecasting services and new observing facilities, in the interests of achieving a profitable activity of the China-Russia Joint Research Center on Space Weather (JRCSW). 相似文献
599.
600.