876 research outputs found
Cluster analysis of regional innovation activity in Russia in 2010-2015
In this article, the indicators of innovation activity in Russian regions are discussed and the regions are divided into five groups, according to their performance in these indicators. Our cluster analysis is based on the recent research and includes several groups of indicators such as innovation activity of enterprises, training of highly qualified personnel, research and development, state support for innovation, and application of innovative technologies. We used the data provided by Rosstat (Federal State Statistics Service) for 83 Russian regions in the period between 2010 and 2015. In terms of their innovation activity, Russian regions can be divided into five groups, two of which are Moscow and St.Petersburg, the two biggest Russian cities that play a special role in Russian economy. Overall, the level of innovation activity in Russia can be assessed as lower middle, although in the given period some regions managed to improve their performance in this sphere. The average level of innovation activity varies considerably across regions, which means that the state innovation policy should be more diversified. Moscow, St.Petersburg, Nizhny Novgorod and Sverdlovsk regions have demonstrated consistent high-level performance and can thus be regarded as prospective centres of innovation. These centres can positively influence the neighbouring areas through the knowledge and technology spillover effect. Although no definitive conclusion can be drawn about the connection between the regions' geographical location and their innovation activity, there is evidence that the most active Russian regions tend to concentrate in the European part of the country. Our findings can be used as guidelines for devising and modifying federal and regional innovation policies.This research was supported by RFBR, research project 18-010-01190 Π ' Models of innovation development factors and comparative advantages analysis in the Russian economyβ
Mesoscopic wave turbulence
We report results of sumulation of wave turbulence. Both inverse and direct
cascades are observed. The definition of "mesoscopic turbulence" is given. This
is a regime when the number of modes in a system involved in turbulence is high
enough to qualitatively simulate most of the processes but significantly
smaller then the threshold which gives us quantitative agreement with the
statistical description, such as kinetic equation. Such a regime takes place in
numerical simulation, in essentially finite systems, etc.Comment: 5 pages, 11 figure
Numerical Verification of the Weak Turbulent Model for Swell Evolution
The purpose of this article is numerical verification of the theory of weak
turbulence. We performed numerical simulation of an ensemble of nonlinearly
interacting free gravity waves (swell) by two different methods: solution of
primordial dynamical equations describing potential flow of the ideal fluid
with a free surface and, solution of the kinetic Hasselmann equation,
describing the wave ensemble in the framework of the theory of weak turbulence.
In both cases we observed effects predicted by this theory: frequency
downshift, angular spreading and formation of Zakharov-Filonenko spectrum
. To achieve quantitative coincidence of the
results obtained by different methods, one has to supply the Hasselmann kinetic
equation by an empirical dissipation term modeling the coherent
effects of white-capping. Using of the standard dissipation terms from
operational wave predicting model ({\it WAM}) leads to significant improvement
on short times, but not resolve the discrepancy completely, leaving the
question about optimal choice of open. In a long run {\it WAM}
dissipative terms overestimate dissipation essentially.Comment: 41 pages, 37 figures, 1 table. Submitted in European Journal of
Mechanics B/Fluid
Second generation diffusion model of interacting gravity waves on the surface of deep fluid
We propose a second generation phenomenological model for nonlinear interaction of gravity waves on the surface of deep water. This model takes into account the effects of non-locality of the original Hasselmann diffusion equation still preserving important properties of the first generation model: physically consistent scaling, adherence to conservation laws and the existence of Kolmogorov-Zakharov solutions. Numerical comparison of both models with the original Hasselmann equation shows that the second generation models improves the angular distribution in the evolving wave energy spectrum
Structure of the Radio Source 3C 120 at 8.4 GHz from VLBA+ Observations in 2002
Maps of the radio source 3C 120 obtained from VLBA+ observations at 8.4 GHz
at five epochs in January - September 2002 are presented. The images were
reconstructed using the maximum entropy method and the Pulkovo VLBImager
software package for VLBI mapping. Apparent superluminal motions of the
brightest jet knots have been estimated. The speeds of jet knots decreases with
distance from the core, changing from 5.40+-0.48c $ to 2.00+-0.48c over 10 mas
(where c is the speed of light) for a Hubble constant of 65 km/s/Mpc. This can
be explained by interaction of the jet with the medium through which it
propagates.Comment: 9 pages, 6 figures, 5 table
The amplifier of unipolar pulses of the short range radar system
The amplifier of videopulses intended for work as a source of a pulse feed of the Hannah diodes 3Π763Π-M of the short range radar system is described. Characteristics of the amplifier are: coefficient of amplification 16 dB; the maximal amplitude of output pulses - 6 V; the maximal current in a pulse - 2,5 A
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