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21.
The basic properties of the dynamic model of a turbulent jet formed by a deep-water sewage discharge into the stratified environment of coastal regions are considered. The model developed was used to estimate the parameters of a floating-up jet of deep wastewater discharge from Sand Island into the basin of Mamala Bay (Hawaii) depending on the season and discharge operation mode. The estimates of the float-up depths of the jet and the initial dilution of the jet were estimated on the basis of model calculations using experimental data on the vertical profiles of the water temperature and salinity under the actual conditions of stratification in the study region. It is shown that the further propagation of the wastewater jet depends on tidal events and internal waves generated by tides. The appearance of turbulent jets at the sea surface was recorded. The model estimates of the parameters of the wastewater discharge were compared with the results of experimental measurements. Good agreement was found, which indicates that the physical mechanisms of the propagation of turbulent jets in a stratified medium are adequately described by the model. 相似文献
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D. S. Drozdov F. M. Rivkin V. Rachold G. V. Ananjeva-Malkova N. V. Ivanova I. V. Chehina M. M. Koreisha Yu. V. Korostelev E. S. Melnikov 《Geo-Marine Letters》2005,25(2-3):81-88
A set of digital maps including geology, Quaternary sediments, landscapes, engineering-geological, vegetation, geocryological and the series of regional sources have been selected to characterize the Russian Arctic coast. Based on this data, new maps of engineering geocryological zoning and zoning of the coast with respect to the intensity of exogenous geological processes and risk of technogenic impacts have been generated at the scales of 1:4,000,000–1:8,000,000. These maps are a tool to assess the impact of industry on the Arctic coast of the country. 相似文献
23.
Various measures including material experiments, centrifuge modeling tests and FEM numerical analyses were performed to study systematically the action mechanism of the geotextile-reinforced cushion under breakwater on soft ground and the effects of the strata characterization and the reinforcement condition on the stability of the breakwater-ground system. In the aspect of controlling the deformation, the geotextile-reinforced cushion under breakwater constrains the lateral displacement of both the embankment and the ground. From the viewpoint of stress, the reinforcement suppressed the range of high stress level in the system. In general, the weaker the ground is and the greater the modulus of the geotextile is, the more effective the reinforcement is. The tensile force in the geotextile is greater in the range of the main part of the embankment. 相似文献
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Yu. A. Rylov 《Astrophysics and Space Science》1989,158(2):297-333
The model of the pulsar magnetosphere filled with massless charged particles (rest massm=0) is considered. The gas of charged massless particles can be found in two different phases: (1) dynamical phase (DP), when the particles move with nonvanishing energy along some base line, determined by the electromagnetic field only, (2) statical phase (SP), when the particles have vanishing energy =0. The pulsar magnetosphere occurs to be divided into regions of different types: (a) the accelerating regions (DP-regions) containing only DP, (b) the capture regions, containing only SP, (3) leaky capture regions, where DP moves through SP. The leaky capture regions are the active regions, which are responsible for the pulsar radioemission. In the case of oblique magnetic moment the equation for the capture surface has been obtained. The capture region is formed around this surface. Expressions for jumps of the electromagnetic field, the current density and the charge density on the capture region boundary have been obtained. The problem of the pulsar magnetosphere is stated mathematically in the case of oblique magnetic moment and ejection of only electrons. 相似文献
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