Physics, mathematics, and technology

Physics, mathematics, and technology

Mathematics and computer science

Representation of projective connections on the SH -distribution of the projective space

Abstract

Projective connections defined by projection and associated to subbundles , L, E of the strong dual threefold distribution (the SH -distribution) of the projective space are constructed. Coverages of torsion-curvature tensors components of the constructed projective connections , ,  of subbundles , L, E of the SH -distribution respectively are given. The way of creation of dual projective connections , ,  corresponding to connections , ,  is specified.

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An influence of initial irregularities geometry on developments of the Rayleigh-Taylor instability in the equatorial F-layer of the ionosphere

Abstract

Results of numerical simulation of the Rayleigh — Taylor instability for different geometrical characteristics of the initial irregularities for evening equatorial conditions based on electrodynamically coherent mathematical model of the equatorial ionosphere F-layer are given. It is shown that increase only in the vertical extent of initial irregularity significantly accelerates development a rayleigh-Taylor bubble whereas increase only in lateral dimensions of initial irregularity insignificantly slows down this development.

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Theoretical and experimental physics

An impacton solution for the vortex filament

Abstract

A new way of construction of exact solutions describing the shape and the dynamics of vortex filaments is described. The new method is based on application of a binary Darboux transformation to the solutions of the nonlinear Schrödinger equation. A new type of solutions is constructed: the impacton. The explicit form of the curvature and torsion of corresponding vortex filament are calculated.

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A simulation of technical support system objects of the regional electrotechnical complex

Abstract

The paper discusses the stages of simulation of large infrastructure projects on the basis of the aggregate method. It is proved that the different stages of the life-cycle units is best modeled using different approaches. In addition, in order to implement energy-saving technologies is advisable to use a system of continuous time using a more complex mathematical structures (mostly– queuing systems).

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On the monitoring of the state of the fiber-optic line

Abstract

A modified method of monitoring optical fibers in the fiber-optic communication lines is presented. Its implementation will allow to more accurately determine the location of the damaged area, to reduce the cost of service lines, to improve the reliability of fiber-optic cables in terms of external negative influences.

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Mechanics

An analysis of mathematical models of the stress state of the outer shell of the roller one-way clutches

Abstract

The outer shell is an important constructive element of roller one-way clutches. Currently, for the calculation of the stress state of the outer shell using the mathematical models obtained based on the essential assumptions. In the article the analysis is carried out and recommendations about use of design mathematical models are made. It is established that at change of number of wedging rollers in a range from 3 to 10 there is a reduction of value of the maximum stress, and in a range from 10 to 20 – increase of stress.

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