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81.
Solar System Research - The possibility of determining the thermophysical characteristics of the lunar soil by a penetrating probe when using solar heat as a heater is considered. The effectiveness...  相似文献   
82.
ABSTRACT

Short stubby piles like monopiles and large diameter drilled shafts undergo rigid body translation and rotation when subjected to a lateral force and/or a moment at the head. A method of analysis for these piles embedded in multi-layered elastic soil is developed using the variational principles of mechanics. Using this analysis, the soil resistance against pile movement can be rigorously related to the soil elastic constants, and the pile head displacement and rotation can be quickly calculated. The equilibrium equations for pile and soil displacements are obtained using the principle of virtual work and solved using an iterative algorithm. Pile responses obtained from the analysis match well with those obtained from three-dimensional finite element analyses in which the same inputs of loads, geometry, and material properties are given. Based on the new analysis, fitted equations for soil resistance parameters are developed, which can be used to directly calculate the pile head displacement and rotation without the use of the iterative algorithm. Numerical examples are provided that demonstrate how the method can be used to analyse practical problems.  相似文献   
83.
Doklady Earth Sciences - A first set of K–Ar isotopic ages obtained, which allowed to estimate the age of the largest volcanoes of the Anaunsky Dol (3.2, 2.2 and 1.9 Ma) and eruptive centers...  相似文献   
84.
Doklady Earth Sciences - Oxidation decomposition of titanomagnetite grains to the magnetite–ilmenite lattice during the formation of igneous rock can lead to thermochemical remanent...  相似文献   
85.
Zhu  H.  Indupriya  M.  Gadi  V. K.  Sreedeep  S.  Mei  G. X.  Garg  A. 《Acta Geotechnica》2020,15(5):1331-1339
Acta Geotechnica - Root depth and leaf area ratio are two important features of a plant and exhibit a coupled relation. Assessing their coupled effects on induced soil suction is essential for...  相似文献   
86.

Problems with compositional data, like spurious correlation and negative bias, are well known in the Geosciences. Not so well known is the fact that the same problems appear when dealing with regionalized compositions. Here, these problems are illustrated, and a solution, based on the principle of working in coordinates using orthonormal logratio representations, is presented. This approach offers a tool for standard geostatistical studies. One of the advantages the method has is that it allows the usual inconsistencies with indicator kriging to be overcome through simplicial indicator kriging. A general way of modelling crossvariograms of coordinates, based on the matrix valued variation variogram, is discussed. In summary, the main aspects related to the modelling and analysis of regionalized compositions have had satisfactory solutions found for them. The proposed methodology is illustrated with public data from a survey concerning arsenic contamination in underground water in Bangladesh.

  相似文献   
87.
Izvestiya, Atmospheric and Oceanic Physics - The phase-screen (split-step) method is widely used for modeling wave propagation in inhomogeneous media. The method of plane phase screens is best...  相似文献   
88.
Izvestiya, Atmospheric and Oceanic Physics - As a result of studies conducted in the city of Derbent, it is established that its monumental fortification structures erected at the end of the 560s...  相似文献   
89.
Doklady Earth Sciences - Based on the results of studying the lithological–geochemical features of the Upper Jurassic–Lower Cretaceous mudrocks and black shales in the Eastern Russian...  相似文献   
90.
Geology of Ore Deposits - The distribution of index minerals of the hydrothermal arsenide process of the formation of Ni‒Co–As (±U–Ag), Co–S–As...  相似文献   
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