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871.
872.
The equations of the mathematical model are solved in terms of special functions. The results for the design scheme of the aircraft forebody are obtained with a guaranteed accuracy by the stable method of functional normalization. 相似文献
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Space Science Reviews - The NRL ionosphere/plasmasphere model SAMI3 has been modified to support the NASA ICON mission. Specifically, SAMI3_ICON has been modified to import the thermospheric... 相似文献
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Lawrence M. Widrow Dongsu Ryu Dominik R. G. Schleicher Kandaswamy Subramanian Christos G. Tsagas Rudolf A. Treumann 《Space Science Reviews》2012,166(1-4):37-70
We review current ideas on the origin of galactic and extragalactic magnetic fields. We begin by summarizing observations of magnetic fields at cosmological redshifts and on cosmological scales. These observations translate into constraints on the strength and scale magnetic fields must have during the early stages of galaxy formation in order to seed the galactic dynamo. We examine mechanisms for the generation of magnetic fields that operate prior during inflation and during subsequent phase transitions such as electroweak symmetry breaking and the quark–hadron phase transition. The implications of strong primordial magnetic fields for the reionization epoch as well as the first generation of stars are discussed in detail. The exotic, early-Universe mechanisms are contrasted with astrophysical processes that generate fields after recombination. For example, a?Biermann-type battery can operate in a proto-galaxy during the early stages of structure formation. Moreover, magnetic fields in either an early generation of stars or active galactic nuclei can be dispersed into the intergalactic medium. 相似文献
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878.
The stress-strain state of thin-walled aircraft structures such as a wing or fuselage made of composite materials is determined
based on the beam theory. The laminated skin is orthotropic. The solution was obtained without using the centroidal principal
section axes and subdividing the problem in shear and torsion. A calculation variant with skin discretization along the section
contour was studied. 相似文献
879.
Hassanali Akbari Asti Bhatt Cesar La Hoz Joshua L. Semeter 《Space Science Reviews》2017,212(1-2):249-294
Space plasmas are host to the electrostatic Langmuir waves and a rich range of processes associated with them. Many of such processes that are of interest in micro-scale plasma physics and magnetosphere-ionosphere physics are open to investigation via incoherent scatter plasma lines—i.e., a pair of resonant peaks in the incoherent scatter radar (ISR) spectrum, symmetrically displaced from the radar transmitting frequency by about the plasma frequency, as the signature of Langmuir waves in the ISR spectrum. There now exists a large body of literature devoted to the investigation of a number of topics in ionospheric physics via plasma line theory and observation. It is the goal of this work to provide a comprehensive review of this literature, from the early theoretical works on oscillations in magnetized plasma to the recent advances in plasma line measurements and applications. This review includes detailed theoretical discussions on the intensity and frequency displacement of plasma lines. It reviews the experimental observations of plasma lines enhanced by various sources of energy and discusses the implications of the observations in the context of ionospheric physics. The review also covers the practical aspects of plasma line measurements, from measurement techniques to the applications of plasma lines in estimating the bulk parameters of the ionosphere. 相似文献
880.