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181.
Vladimir Nikora 《Acta Geophysica》2007,55(1):3-10
Hydrodynamics of aquatic ecosystems is a relatively new, emerging multidisciplinary research area dealing with two key inter-connected
issues: (i) physical interactions between flow and organisms (e.g., due to drag forces); and (ii) ecologically relevant mass-transfer-uptake
processes (e.g., due to molecular and turbulent diffusion). Owing to physical and biological complexity of boundary conditions
in aquatic systems, the conventional hydraulic methodologies are often impracticable and new approaches are required. One
of such approaches, the double-averaging methodology, is discussed with particular focus on flows over biologically-modified
beds. 相似文献
182.
Grigory I. Dolgikh Stanislav G. Dolgikh Sergei N. Kovalev Vladimir V. Ovcharenko Vladimir A. Chupin Vyacheslav A. Shvets Sergei V. Yakovenko 《Acta Geophysica》2007,55(4):607-618
The experimental data in the microseismic frequency range obtained using the seismo-acoustic-hydrophysical measurement complex
are analyzed. The emphasis is put on estimating the ratio between the energy of surface sea wind waves in the area of the
Japan Sea where the complex was located and the Earth’s crust microdeformations in this frequency range. The experimental
evaluate obtained allow us to estimate the energy re-distribution at the hydrosphere-lithosphere boundary. 相似文献
183.
Joachim?MiksatEmail author Friedemann?Wenzel Vladimir?Sokolov 《Pure and Applied Geophysics》2005,162(5):857-874
The August 17, 1999 Kocaeli earthquake ruptured the earths surface along 145 km and produced a magnitude of Mw=7.4. As expected for such an event Modified Mercalli intensities of typically IX and X in the vicinity of the fault were determined. Yet the observed accelerations at the five near-fault sites remained amazingly small with horizontal PGA values of 0.14 g to 0.4 g. We attempt to resolve the enigma by modeling surface ground motion with a finite-difference algorithm, utilizing two different rupture and slip histories derived from the strong-motion observations and translate the computed horizontal motion in intensity values. We can show that (a) in a given simple crustal velocity model different slip distributions result in significantly different ground motion distributions in the vicinity of the fault even though both slip distributions fit the observed accelerometer data quite well. (b) Both slip distributions project high ground motion into areas adjacent to the fault where no accelerometer was located. (c) Both slip distributions are not fully compatible with observed intensity observations around the fault, although this could be partly attributed to the lack of knowledge regarding to the crustal structure. In the light of our results it would thus be misleading if the few strong-motion observations around the Kocaeli earthquake fault were taken as typical or representative for the entire area and for potential future events. 相似文献
184.
Vladimir A. Osherovich 《Astrophysics and Space Science》1982,86(2):453-469
One procedure for solving MHD equations is to search for a solution in an area that is restricted by boundary surfaces. This procedure requires the magnetic field to be truncated on the boundary. As a result, boundary current sheets appear. This approach is certainly acceptable for laboratory plasma experiments in which these surfaces are made of metal. For astrophysically relevant plasma, an alternative approach has been formulated by the author. We require the total magnetic energy,W, to be finite and, simultaneously, the magnetic fieldB to be continuous. The proposed approach leads to an eigenvalue problem that is treated analytically. The complete set of exact MHD solutions with multi-toroidal structure is obtained. These solutions are applied to coronal loops and transients, using the similarity assumption for time-dependent solutions.The derived pressure and density excess distributions are discussed. The estimation of the total mass excess, as well as the minimum value of the magnetic field intensity, is demonstrated. An indirect way of obtaining magnetic field measurements for transients, based on the developed model, is proposed. 相似文献
185.
Ara K. Avetissian Martin H. Minassian Vladimir V. Papoyan 《Astrophysics and Space Science》1980,69(1):71-77
The solution of the system of Maxwell-Einstein equations, which determines the external gravitational and electromagnetic fields of magneto-dipole configurations, has been obtained to a quadratic approximation of magnetic momentum. 相似文献
186.
Vladimir N. Shinkin 《Celestial Mechanics and Dynamical Astronomy》2001,79(4):321-322
Volume Contents
Contents Volume 79 相似文献187.
188.
The principal results of triggered-lightning experiments conducted at the International Center for Lightning Research and Testing (ICLRT) at Camp Blanding, Florida, from 1993 through 2002 are reviewed. These results include (a) characterization of the close lightning electromagnetic environment, (b) first lightning return-stroke speed profiles within 400 m of ground, (c) new insights into the mechanism of the dart-stepped (and by inference stepped) leader, (d) identification of the M-component mode of charge transfer to ground, (e) first optical image of upward connecting leader in triggered-lightning strokes, (f) electric fields in the immediate vicinity of the lightning channel, (g) inferences on the interaction of lightning with ground and with grounding electrodes, (h) discovery of X-rays produced by triggered-lightning strokes, (i) new insights into the mechanism of cutoff and reestablishment of current in rocket-triggered lightning. Selected results are discussed. 相似文献
189.
Vladimir Lyakhovsky Yehuda Ben-Zion Amotz Agnon 《Geophysical Journal International》2005,161(1):179-190
190.