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991.
992.
The deformation, of embankment has serious influences on neighboring structure and infrastructure. A trial embankment is reanalyzed by elastoplastic damage model coupling Blot' s consolidation theory. With the increase in time of loading, the damage accumulation becomes larger. Under the centre and toe of embankment, damage becomes serious. Under the centre of embankment, vertical damage values are bigger than horizontal ones. Under the toe of embankment, horizontal damage values are bigger than vertical ones.  相似文献   
993.
994.
In this paper we present a new symbolic processor specially suited for the Earth rotation theory. This processor works with a more general kind of Poisson series called Kinoshita series, which has resulted to be very useful in the Earth rotation theory. Its structure is adapted for dealing with the more general analytical expressions that appear in the Earth rotation theory. This new algebraic processor has been successfully used for computing different contributions to the nutation series of the rigid Earth.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   
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The recent detection of very-high-energy (GeV – TeV) γ-ray emission from the Galactic black-hole candidate and microquasar LS 5039 has sparked renewed interest in jet models for the high-energy emission in those objects. In this work, we have focused on models in which the high-energy emission results from synchrotron and Compton emission by relativistic electrons in the jet (leptonic jet models). Particular attention has been paid to a possible orbital modulation of the high-energy emission due to azimuthal asymmetries caused by the presence of the companion star. Both orbital-phase dependentγγ absorption and Compton scattering of optical/UV photons from the companion star may lead to an orbital modulation of the gamma-ray emission. We make specific predictions which should be testable with refined data from HESS and the upcoming GLAST mission.  相似文献   
998.
We present general relativistic solutions for self-similar spherical perturbations in an expanding cosmological background of cold pressure-less gas. We focus on solutions having shock discontinuities propagating in the surrounding cold gas. The pressure, p , and energy density, μ, in the shock-heated matter are assumed to obey   p = w μ  , where w is a positive constant. Consistent solutions are found for shocks propagating from the symmetry centre of a region of a positive density excess over the background. In these solutions, shocks exist outside the radius marking the event horizon of the black hole which would be present in a shock-less collapse. For large jumps in the energy density at the shock, a black hole is avoided altogether and the solutions are regular at the centre. The shock-heated gas does not contain any sonic points, provided the motion of the cold gas ahead of the shock deviates significantly from the Hubble flow. For shocks propagating in the uniform background, sonic points always appear for small jumps in the energy density. We also discuss self-similar solutions without shocks in fluids with   w < −1/3  .  相似文献   
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