The spread of the COVID-19 infection in Russia’s Baltic macro-region: internal differences
... Geography of Lomonosov Moscow State University
To stop the spatial diffusion of COVID-19, some Baltic regions (the spaces of places) imposed restrictions on movement in the local labour market, whilst others (the spaces of flows) tried to limit both horizontal movements in the local labour market and hierarchical ones between the city centre and rural district periphery, a core town and a core town of a lower order.
To find local factors differentiating the course of the pandemic, we examined a set ...
Connection in a tangent bundle to the frame bundle of manifold
This paper focuses on the tangent bundle to the linear frame bundle of a smooth manifold. Brackets of the tangent vectors of this bundle are con-structed. A coordinate representation of the non-holonomic frame vectors is produced. Horizontal and vertical curvatures, torsions, and covariant derivatives are constructed in a homogeneous connection.
Бишоп Р., Криттенден Р. Геометрия многообразий. М., 1967.
2. Кобаяси Ш., Номидзу ...
A new way of solving the problem of the sinusoidal waves on the surface of a homogeneous perfect fluid
We consider a new way of solving the problem of the sinusoidal wave on the surface of a homogeneous perfect fluid. Its feature is used instead of the potential speed of the original characteristics of wave motion: horizontal and vertical components of the velocity and pressure. It is noted that it will generalize the problem under consideration in the event of a multi-layer liquid. The results, including the dispersion relation, fully consistent with the known....