534 research outputs found
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
Π‘ΠΎΡΠΈΠ°Π»ΡΠ½Π°Ρ ΠΏΠΎΠ΄Π΄Π΅ΡΠΆΠΊΠ° ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΠΉ ΠΌΠΎΠ΄Π΅ΡΠ½ΠΈΠ·Π°ΡΠΈΠΈ Π² ΡΠ΅Π³ΠΈΠΎΠ½Π°Ρ Π‘ΠΈΠ±ΠΈΡΠΈ
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.Π‘ΡΠ°ΡΡΡ ΠΏΠΎΡΠ²ΡΡΠ΅Π½Π° ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΡΠΎΡΠΈΠ°Π»ΡΠ½ΠΎ-ΡΠΊΠΎΠ½ΠΎΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
, ΡΠΎΡΠΈΠΎΠ΄Π΅ΠΌΠΎΠ³ΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΈ ΡΠΎΡΠΈΠΎΠΊΡΠ»ΡΡΡΡΠ½ΡΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ ΡΠΊΠΎΠ½ΠΎΠΌΠΈΡΠ΅ΡΠΊΠΈ Π°ΠΊΡΠΈΠ²Π½ΠΎΠ³ΠΎ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½Π½ΠΎΠ³ΠΎ Π½Π°ΡΠ΅Π»Π΅Π½ΠΈΡ ΡΠ΅Π³ΠΈΠΎΠ½ΠΎΠ² Π‘ΠΈΠ±ΠΈΡΡΠΊΠΎΠ³ΠΎ ΡΠ΅Π΄Π΅ΡΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΠΎΠΊΡΡΠ³Π°. ΠΠ±ΡΠ΅ΠΊΡ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡΒ β ΡΠ΅Π·ΠΈΠ΄Π΅Π½ΡΡ Π‘ΠΈΠ±ΠΈΡΠΈ, ΠΎΠ±Π»Π°Π΄Π°ΡΡΠΈΠ΅ Π²ΡΡΠΎΠΊΠΈΠΌ ΡΠ΅Π»ΠΎΠ²Π΅ΡΠ΅ΡΠΊΠΈΠΌ ΠΊΠ°ΠΏΠΈΡΠ°Π»ΠΎΠΌ ΠΈ ΠΏΠ΅ΡΡΠΏΠ΅ΠΊΡΠΈΠ²ΠΎΠΉ Π΄Π΅ΠΉΡΡΠ²ΠΈΡ Π² ΠΊΠ°ΡΠ΅ΡΡΠ²Π΅ ΡΠΎΡΠΈΠ°Π»ΡΠ½ΠΎΠΉ ΠΏΠΎΠ΄Π΄Π΅ΡΠΆΠΊΠΈ ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΠΉ ΠΌΠΎΠ΄Π΅ΡΠ½ΠΈΠ·Π°ΡΠΈΠΈ ΠΈΡ
ΡΠ΅Π³ΠΈΠΎΠ½ΠΎΠ². ΠΠ° ΠΎΡΠ½ΠΎΠ²Π΅ Π°Π½Π°Π»ΠΈΠ·Π° ΠΎΡΠΈΡΠΈΠ°Π»ΡΠ½ΠΎΠΉ ΡΡΠ°ΡΠΈΡΡΠΈΠΊΠΈ ΠΈ ΠΈΠ·ΡΡΠ΅Π½ΠΈΡ Π½Π°ΡΠ΅Π»Π΅Π½ΠΈΡ Π² ΡΠ΅Π³ΠΈΠΎΠ½Π°Ρ
Π‘ΠΈΠ±ΠΈΡΠΈ ΡΠ΄Π΅Π»Π°Π½Π° ΠΎΡΠ΅Π½ΠΊΠ° ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°ΡΠ΅Π»ΡΠ½ΠΎΠ³ΠΎ ΠΏΠΎΡΠ΅Π½ΡΠΈΠ°Π»Π° Π²Π½ΡΡΡΠ΅Π½Π½Π΅ΠΉ ΠΌΠΈΠ³ΡΠ°ΡΠΈΠΈ ΠΈ ΡΠΎΡΠΈΠΎΠΊΡΠ»ΡΡΡΡΠ½ΡΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ ΠΏΠΎΡΠ΅Π½ΡΠΈΠ°Π»ΡΠ½ΡΡ
Π°Π³Π΅Π½ΡΠΎΠ² ΠΌΠΎΠ΄Π΅ΡΠ½ΠΈΠ·Π°ΡΠΈΠΈ ΡΡΠ΅Π΄ΠΈ Π½Π°ΡΠ΅Π»Π΅Π½ΠΈΡ ΡΡΠΈΡ
ΡΠ΅ΡΡΠΈΡΠΎΡΠΈΠΉ
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 we perform Lie group classification,
which identifies 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
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