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261.
A preliminary model is proposed to describe quantitatively the position and movement of cusp equatorward boundary. This integrated model, consisting of an empirical model of the magnetopause and a compressed dipolar model of Open/Closed field line, connects quantitatively the solar wind conditions, subsolar magnetopause and cusp equatorward boundary. It is shown that the increasing solar wind dynamic pressure and the increasing southward Interplanetary Magnetic Field (IMF) component drive the magnetopause to move inward and the cusp equatorward. This model is adopted to interpret quantitatively the cusp movement of August 14, 2001 observed by Cluster. The results show that the subsolar magnetopause moved earthward from 10.7 He to 9.0 Re during the period of 002300-002800 UT, and correspondingly the cusp equatorward boundary shifted equatorward. The observations of Cluster C1 and C4 show the cusp equatorward boundary that Cluster Cl and C4 were crossing during same interval moved equatorward by 4.6°. The cusp equatorward boundary velocity computed in the theoretical model (10.7km/s) is in good agreement with the observed value (9.4km/s) calculated from the data of CIS of Cluster C4 and C1. 相似文献
262.
Z Shi D Zhuang E A Ilyin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1998,21(8-9):1145-1150
Space flight experiments on Chinese silkworm (Bombyx mori L.) were conducted on board the Russian 10th Biosatellite for 12 days. The samples included silkworm eggs, larvae, cocoons, pupae and moths. The processes of spinning, cocooning, mating, oviposition, larval hatching, pupation and moth emergence all completed well in space. The following effects of space flight on silkworm development were observed: The times of hatching and oviposition in the flight group were 2 to 3 days earlier than in the control group; the hatching rate of diapause eggs during space flight seemed higher than that of the control group; the life span of 2 of the 7 varieties flown was shortened; genetical variations appeared in 3 varieties. The results showed that the embryonic stage was probably the period most sensitive to the space flight environment. 相似文献
263.
A. T. Y. Lui C. Jacquey G. S. Lakhina R. Lundin T. Nagai T.-D. Phan Z. Y. Pu M. Roth Y. Song R. A. Treumann M. Yamauchi L. M. Zelenyi 《Space Science Reviews》2005,116(3-4):497-521
The idea of expedient energy transformation by magnetic reconnection (MR) has generated much enthusiasm in the space plasma community. The early concept of MR, which was envisioned for the solar flare phenomenon in a simple two-dimensional (2D) steady-state situation, is in dire need for extension to encompass three-dimensional (3D) non-steady-state phenomena prevalent in space plasmas in nature like in the magnetosphere. A workshop was organized to address this and related critical issues on MR. The essential outcome of this workshop is summarized in this review. After a brief evaluation on the pros and cons of existing definitions of MR, we propose essentially a working definition that can be used to identify MR in transient and spatially localized phenomena. The word “essentially” reflects a slight diversity in the opinion on how transient and localized 3D MR process might be defined. MR is defined here as a process with the following characteristics: (1) there is a plasma bulk flow across a boundary separating regions with topologically different magnetic field lines if projected on the plane of MR, thereby converting magnetic energy into kinetic particle energy, (2) there can be an out-of-the-plane magnetic field component (the so-called guide field) present such that the reconnected magnetic flux tubes are twisted to form flux ropes, and (3) the region exhibiting non-ideal MHD conditions should be localized to a scale comparable to the ion inertial length in the direction of the plasma inflow velocity. This definition captures the most important 3D aspects and preserves many essential characteristics of the 2D case. It may be considered as the first step in the generalization of the traditional 2D concept. As a demonstration on the utility of this definition, we apply it to identify MR associated with plasma phenomena in the dayside magnetopause and nightside magnetotail of the Earth’s magnetosphere. How MR may be distinguished from other competing mechanisms for these magnetospheric phenomena are then discussed.This revised version was published online in July 2005 with a corrected cover date. 相似文献
264.
Fisk L. A. Wenzel K.-P. Balogh A. Burger R. A. Cummings A. C. Evenson P. Heber B. Jokipii J. R. Krainev M. B. Kóta J. Kunow H. Le Roux J. A. McDonald F. B. McKibben R. B. Potgieter M. S. Simpson J. A. Steenberg C. D. Suess S. Webber W. R. Wibberenz G. Zhang M. Ferrando P. Fujii Z. Lockwood J. A. Moraal H. Stone E. C. 《Space Science Reviews》1998,83(1-2):179-214
The global processes that determine cosmic ray modulation are reviewed. The essential elements of the theory which describes cosmic ray behavior in the heliosphere are summarized, and a series of discussions is presented which compare the expectations of this theory with observations of the spatial and temporal behavior of both galactic cosmic rays and the anomalous component; the behavior of cosmic ray electrons and ions; and the 26-day variations in cosmic rays as a function of heliographic latitude. The general conclusion is that the current theory is essentially correct. There is clear evidence, in solar minimum conditions, that the cosmic rays and the anomalous component behave as is expected from theory, with strong effects of gradient and curvature drifts. There is strong evidence of considerable latitude transport of the cosmic rays, at all energies, but the mechanism by which this occurs is unclear. Despite the apparent success of the theory, there is no single choice for the parameters which describe cosmic ray behavior, which can account for all of the observed temporal and spatial variations, spectra, and electron vs. ion behavior. 相似文献
265.
M.-J. Martres Z. Mouradian I. Soru-Escaut 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(7):31
The homologous flares observed in the same region of a spotgroup testify the existence and the duration of a permanent instability. However, they also attest that the general magnetic configuration is not destroyed by these flares and that it changes up to the death of the site.The study of every flaring sites where more than ten flares occur has been performed in Meudon for the 1974–1980 period.One hundred and sixty-six sites have been analysed from the rotation where the A.R. is observed up to five rotations ahead. The basis of the study are the “Synoptic Maps”. A relation is found between the presence of crossing of “filament-phantom” corridors and the location of the homologous flare sites.1 相似文献
266.
Z. Zhu Z.B. Zhou L. Cai Y.Z. Bai J. Luo 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
Satellite gravity gradiometry has been applied in GOCE mission to obtain higher harmonics of the Earth’s gravity mapping. In-orbit results showed that the precision of GOCE gradiometry achieved a level of 10–20 mE/Hz1/2 in the bandwidth of 38–100 mHz, and the major error source came from the intrinsic noise of the core sensor electrostatic accelerometer. Two schemes for improving sensitivity of such accelerometer are presented by optimizing the parameters to reduce the dynamic range and choosing the heavier proof mass to suppress the thermal noise limited by the discharging gold wire. As a result, an accelerometer with a better resolution of 6.6×10−13 m/s2/Hz1/2 could be developed, and then a precision of 3 mE/Hz1/2, corresponding to a spatial resolution of about 78 km half wavelength, is achievable for the future satellite gradiometric mission. 相似文献
267.
N. I. Moskalenko R. Sh. Misbakhov I. Z. Bagautdinov N. F. Loktev I. R. Dodov 《Russian Aeronautics (Iz VUZ)》2016,59(3):419-425
The application of the method of absorbing fine-structure spectroscopy to determine the composition of ingredient emissions of products of combustion of the turbojet engine. Applied for research of ingredient composition of complex spectrophotometric instrumentation provides a measurement of the concentration of the various ingredients in the products of combustion to limit sensitivity of 1–10 ppm. The technology of measurement and processing of the data of spectrometric measurements are discussed. The results of measurements of the ingredient composition released into the atmosphere of the combustion products of the turbojet engine are analysed. 相似文献
268.
A method for providing the required location of a transfer zero set in the linear multiconnected dynamic system with an equal number of inputs and outputs is considered. 相似文献
269.
A class of current injection based three-phase high power factor rectifiers is proposed. Low distortion of the input currents and high power factor are obtained applying near optimal current injection. The optimal current injection is discussed, and requirements it imposes to the current injection network are derived. A class of simple current injection networks that provide near optimal current injection, consisting of a transformer, two capacitors, and a number of resistors or resistance emulators is proposed. The power processed by the resistors or resistance emulators is shown to be 8.81% of the input power. Design of the current injection network is discussed, and dependence of the input current distortion on capacitance of the applied capacitors is analyzed. Volt-ampere rating of the transformer is shown to be only 0.16% of the input power. Effects caused by the output current ripple are studied, and a method for their compensation is proposed. Analytical results are experimentally verified. Switching resistance emulation is discussed and its feasibility is experimentally demonstrated 相似文献
270.