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Moscow, Russia

Moscow Timiryazev Agricultural Academy is one of the oldest agrarian educational institution in Russia. It was founded on December 3, 1865. It is under the Supervisory of the Russian Ministry of Agriculture Wikipedia.

Zolotarevskaya D.I.,Russian State Agricultural University
Eurasian Soil Science

Field studies of the rheological properties of loamy sandy soddy-podzolic soils were performed. Within the studied ranges of the soil moistening and bulk density values, the soils behaved as viscoelastic bodies. The dynamic deformation of such soils under compressive stress was modeled by a differential equation of the first order linking the compressive stress, the rate of its changes, and the relative soil deformation in the vertical direction. Correlative relationships between the viscoelastic soil properties, the soil bulk density, the soil water content, and the angular frequency of the harmonic law of the soil deformation were obtained. The methods of calculation of the soil bulk density as dependent on the initial bulk density and the mode of the soil deformation upon cyclic loads by rigid cylinders and by elastic wheels were developed. These methods were realized in a computer program for the quantitative assessment of the effect of the major factors on the changes in the rheological properties, the indices of the soil deformation, and the soil bulk density under the impact of compressive loads. It was shown that an increase in the number of loading-unloading cycles leads to the transformation of the viscoelastic soil properties into elastic properties. © Pleiades Publishing, Ltd. 2010. Source

Eskov E.K.,Russian State Agricultural University | Toboev V.A.,Chuvash State University
Entomological Review

The thermal imaging method was used to monitor thermal processes in the inter-comb bee clusters and temperature of different body parts during the wintering period. The temperature of different body parts was found to depend on the localization of bees in the nest and the external temperature. The dependence of the thermoregulatory activity of bees on the external temperature fluctuations decreased during wintering. The trends of distribution of thermal fields in clusters of wintering bees are revealed. © 2011 Pleiades Publishing, Ltd. Source

Blinov A.P.,Russian State Agricultural University
Mechanics of Solids

We consider the problem of motion of a heavy particle on the surface of a torus with horizontal axis of rotation. On nondevelopable surfaces other than surfaces of revolution with vertical axis, the solution is known only for the surface of an elliptic paraboloid [1]. To solve the problem on the surface of a torus with horizontal axis of rotation, we use the method of reduction of equations of motion proposed in [2]. We construct the asymptotics of the general and periodic solutions and show that one can use this asymptotics when studying the motion of a heavy particle on an elliptic torus. We obtain the stability conditions in the first approximation for the particle motion along the outer equator and the lower meridian of the torus. © Allerton Press, Inc., 2010. Source

Blinov A.P.,Russian State Agricultural University
Mechanics of Solids

The problem of unwinding, under zero gravity, of a pair of dynamically identical bodies (dumbbell-shaped spacecraft) connected by an inextensible weightless film wound as a roll around the cylindrical surfaces of the bodies is considered. In the prelaunch position, the axes of these surfaces are parallel to each other and equidistant from the cluster rotation axis. The film winding direction is consistent with the direction of the cluster rotation so that, after the holding locks are opened, the bodies begin to move away from each other under the action of centrifugal forces, thus pulling and unwinding the film. It is assumed that the film median passes through the cluster center of mass. A pair of cords bounding an imaginary film can be used instead of the actual film as well. Some basic relations between the cluster motion parameters in the unwinding process are obtained. A scheme for describing the unwinding of clusters of any number of dynamically identical polygonshaped bodies is proposed. © Allerton Press, Inc., 2015. Source

Barvinsky A.O.,Russian State Agricultural University | Kamenshchik A.Y.,University of Bologna | Kamenshchik A.Y.,L D Landau Institute For Theoretical Physics | Nesterov D.V.,RAS Lebedev Physical Institute
European Physical Journal C

We present a detailed derivation of the recently suggested new type of hill-top inflation [arXiv:1509.07270] originating from the microcanonical density matrix initial conditions in cosmology driven by conformal field theory (CFT). The cosmological instantons of topology (Formula presented.), which set up these initial conditions, have the shape of a garland with multiple periodic oscillations of the scale factor of the spatial S3-section. They describe underbarrier oscillations of the inflaton and scale factor in the vicinity of the inflaton potential maximum, which gives a sufficient amount of inflation required by the known CMB data. We build the approximation of two coupled harmonic oscillators for these garland instantons and show that they can generate inflation consistent with the parameters of the CMB primordial power spectrum in the non-minimal Higgs inflation model and in R2 gravity. In particular, the instanton solutions provide smallness of inflationary slow-roll parameters (Formula presented.)0 and their relation (Formula presented.) characteristic of these two models. We present the mechanism of formation of hill-like inflaton potentials, which is based on logarithmic loop corrections to the asymptotically shift-invariant tree-level potentials of these models in the Einstein frame. We also discuss the role of (Formula presented.)-gravity as an indispensable finite renormalization tool in the CFT driven cosmology, which guarantees the non-dynamical (ghost free) nature of its scale factor and special properties of its cosmological garland-type instantons. Finally, as a solution to the problem of hierarchy between the Planckian scale and the inflation scale we discuss the concept of a hidden sector of conformal higher spin fields. © 2015, The Author(s). Source

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