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Grigorenko A.Y.,Ukrainian Academy of Sciences | Loza I.A.,National Transport University
International Applied Mechanics | Year: 2013

The propagation of nonaxisymmetric waves in layered hollow cylinders with radially polarized piezoceramic layers is studied. The associated problem is solved with an effective numerical-analytic method. The original three-dimensional problem of electroelasticity for partial differential equations is reduced to a boundary-value eigenvalue problem for ordinary differential equations by representing the components of the stiffness tensor, displacement vectors, electric-flux density, and electrostatic potential as standing circumferential waves and traveling axial waves. The problem is solved with the stable discrete-orthogonalization method in combination with the incremental search method. The dispersion equations are numerically analyzed over a wide range of variation in the geometrical characteristics of cylinders with piezoceramic layers © 2013 Springer Science+Business Media New York. Source


Zinko R.,National Transport University
Vibrations in Physical Systems | Year: 2014

The use of graphs for the research of a rotor crush machine work on elastic foundation is offered. For machines the structure graph of its design is being written. The graph of levels structure of the generalized coordinates of mathematical model is being formed on the basis of structure graph of machine design. It allows building of the mathematical model, which describe the physical processes of the machine work quickly and qualitatively. © by Poznan University of Technology, Poznan, Poland 2014. Source


Khoroshev K.G.,National Transport University
International Applied Mechanics | Year: 2010

Generalized complex potentials, their expressions for a domain with elliptic holes, and the discrete least-squares method are used to analyze the generalized plane electroelastic state of a piezoelectric plate having holes and cracks with electric potentials applied to their boundaries. There are no mechanical loads. A numerical analysis is conducted. The effect of the applied voltage on the electroelastic state of the plate is examined © 2010 Springer Science+Business Media, Inc. Source


Gladush V.D.,Dnipropetrovsk National University | Galadgyi M.V.,National Transport University
General Relativity and Gravitation | Year: 2011

We propose the method of investigation of radial motions for charged and neutral test particles in the Reissner-Nordström field by means of mass potential. In this context we analyze special features of interaction of charges and their motions in General Relativity and construct the radial motion classification. For test particles and a central source with charges q and Q, respectively, the conditions of attraction (when qQ > 0) and repulsion (when qQ < 0) are obtained. The conditions of motionless test particle states with respect to the central source are investigated and, in addition, stability conditions for such static equilibrium states are found. It is shown that stable states are possible only for the bound states of weakly charged particles in the field of a naked singularity. Frequencies of small oscillations of test particles near their equilibrium positions are also found. © 2011 Springer Science+Business Media, LLC. Source


Sopotsko O.Y.,National Transport University
Actual Problems of Economics | Year: 2014

The article describes the conditions of the cycle for food products (perishable cargo) delivery and the requirements to the logistics delivery cycle for such cargos. The algorithm to solve practical problems of this logistics cycle optimization is offered. An example of this algorithm use is given along with the best routes for cargo delivery from stock to retail outlets is provided. Source

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