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61.
Gorchakov G. I. Sitnov S. A. Karpov A. V. Gorchakova I. A. Gushchin R. A. Datsenko O. I. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(3):261-270
Izvestiya, Atmospheric and Oceanic Physics - The technique for constructing the spatial distribution of maximum aerosol optical depth (MAOD) has been used to estimate the optically dense haze... 相似文献
62.
Izmailov I. S. Shakht N. A. Polyakov E. V. Gorshanov D. L. Pogodin M. A. 《Astrophysics》2021,64(2):160-171
Astrophysics - This paper is a continuation of our earlier work devoted to determining the orbit and mass of the star 61 Cyg and the changes in the photometric characteristics of its components.... 相似文献
63.
Solar System Research - The discovery of the first interstellar comet 2I/Borisov confirmed the astronomers’ speculation that the passage through the solar system of relatively large objects... 相似文献
64.
Pavlenko E. P. Sosnovskii A. A. Antonyuk K. A. Antonyuk O. I. Pit’ N. V. Kokhirova G. I. Rakhmatullaeva F. J. Baklanov A. V. 《Astrophysics》2021,64(3):293-305
Astrophysics - Photometric studies of the type SU UMa dwarf nova NY Her were made during 2017 and 2020 at the Crimean Astrophysical Observatory and at the Sanglokh Observatory over a total of 77... 相似文献
65.
Geomagnetism and Aeronomy - Measurements of the differential fluxes of energetic electrons in the equatorial region of the magnetosphere in the energy range from units of keV to hundreds of keV... 相似文献
66.
Geomagnetism and Aeronomy - Stable auroral red (SAR) arcs are the result of the interaction of energetic ring current ions with the outer plasmasphere (plasmapause). The article analyzes the... 相似文献
67.
Geomagnetism and Aeronomy - The solar influence on long-term climatic processes of Earth has been studied with the use of long-term series of historical reconstructions of Total Solar Irradiation... 相似文献
68.
Opekunov A. Yu. Mitrofanova E. S. Spasskii V. V. Opekunova M. G. Sheinerman N. A. Chernyshova A. V. 《Water Resources》2020,47(2):282-293
Water Resources - The article gives the results of integrated studies of bottom sediments in four watercourses in the central St. Petersburg: the rivers of Ekateringofka, Okhta, Fontanka, and... 相似文献
69.
Water Resources - The possible input of nutrients-pollutants into water bodies in the Upper Volga basin from agricultural lands is evaluated for the case of the Yakhroma R. with a basin area of... 相似文献
70.
A multiscale strategy is evaluated at a structural level for the analysis of unreinforced masonry structures. The mechanical characterization of the masonry is deduced from homogenization-based micro-scale finite element (FE) models. The derived data are here employed at a structural level via a discrete FE model. The discrete FE model is composed of quadrilateral rigid plates interconnected through vertical and horizontal interfaces. On the interfaces, between adjoining discrete elements, a model that accounts for the in- and out-of-plane behavior of masonry, with damage and plasticity, is adopted. Such interfaces represent the material pre- and post-peak regimes, its orthotropy, and, depending on the micro-model assumed, account by three-dimensional shear effects that are especially important for multi-leaf walls and complex regular textures. The discrete model has been implemented in an advanced structural analysis software where powerful built-in features as the arc-length method, line-search algorithm, and implicit or explicit solver schemes are available. The multi-scale model is applied for the dynamic study of a small English-bond masonry house prototype subjected to a series of consecutive earthquake records. Detailed comparisons between the experimental and numerical data are presented, including the results obtained through a continuous total strain rotating crack model. Quasi-static and dynamic analyses are conducted. Results demonstrate that when enough experimental information is available on the masonry components under tension, shear, and compression regimes, the approach predicts well the seismic structural response in terms of time-history displacements, seismic capacity, and damage patterns. The required computational cost (CPU time) is very attractive. 相似文献