Lagrangian formalism and Noether-type theorems for second-order delay ODEs

The Lagrangian formalism for variational problem for second-order delay ordinary differential equations (DODEs) is developed. The Noether-type operator identities and theorems for DODEs of second order are presented. Algebraic construction of integrals for DODEs based on symmetries are demonstrated by examples

Социальная поддержка современной модернизации в регионах Сибири

The article is devoted to the study of socio-economic, socio-demographic and socio-cultural characteristics of the economically active educated population of the regions of Siberian Federal District. The object of the study is residents of Siberia, who have high human capital and prospect of acting as a social support for contemporary modernization of their regions. Based on the analysis of official statistics and surveys of the population in the regions of Siberia, an assessment of the educational potential of internal migration and socio-cultural characteristics of potential agents of modernization in the population of these territories is made.Статья посвящена исследованию социально-экономических, социодемографических и социокультурных характеристик экономически активного образованного населения регионов Сибирского федерального округа. Объект исследования – резиденты Сибири, обладающие высоким человеческим капиталом и перспективой действия в качестве социальной поддержки современной модернизации их регионов. На основе анализа официальной статистики и изучения населения в регионах Сибири сделана оценка образовательного потенциала внутренней миграции и социокультурных характеристик потенциальных агентов модернизации среди населения этих территорий

One-dimensional MHD flows with cylindrical symmetry: Lie symmetries and conservation laws

A recent paper considered symmetries and conservation laws of the plane one-dimensional flows for magnetohydrodynamics in the mass Lagrangian coordinates. This paper analyses the one-dimensional magnetohydrodynamics flows with cylindrical symmetry in the mass Lagrangian coordinates. The medium is assumed inviscid and thermally non-conducting. It is modeled by a polytropic gas. Symmetries and conservation laws are found. The cases of finite and infinite electric conductivity need to be analyzed separately. For finite electric conductivity $\sigma (\rho,p)$ we perform Lie group classification, which identifies $\sigma (\rho,p)$ cases with additional symmetries. The conservation laws are found by direct computation. For cases with infinite electric conductivity variational formulations of the equations are considered. Lie group classifications are obtained with the entropy treated as an arbitrary element. A variational formulation allows to use the Noether theorem for computation of conservation laws. The conservation laws obtained for the variational equations are also presented in the original (physical) variables

Coherent addition of two dimensional array of fiber lasers

Configurations for efficient free space coherent addition of four separate fiber lasers arranged in two dimensional array are presented. They include compact and robust interferometric combiners that can be inserted either inside or outside the cavity of the combined lasers system. The results reveal that over 85% combining efficiency can be obtained.Comment: To be published in Optics Communicatio

Investigation of working processes in a flowing channel of ramjet engine

The technique and results of experimental-theoretical study of gas-dynamics, heat transfer and the structure of gas-flow in the flowing channel of a ramjet engine in Mach number range M = (5-7) are presented. The temperature distribution along the flowing channel of a ramjet engine was experimentally obtained. The temperature along the wall of the flowing channel of the axisymmetric model was measured using the developed thermoprobe. Distributions of Mach number and temperature along the symmetry axis of the flowing channel of the model are obtained numerically. Comparison of the numerical and experimentally obtained values of the Mach number showed their qualitative agreement

Economic concept of food development of Russian market

At present, the Russian economy is developing in the conditions of imposed sanctions on high-tech means of production by foreign countries. In this situation, the development vector is the formation of import substitution policies and the solution of food safety issues for various types of food products that are strategically important for human life. Meeting the needs of the country's population with its own production is a priority for the development of the agrarian market, which makes it possible to develop the production agrarian sector, the processing and trade sphere, to create additional jobs, thereby improving the quality and standard of living of people.peer-reviewe