A hybrid WKB–Galerkin method applied to a piezoelectric sandwich plate vibration problem considering shear force effects

Optimization of inventory management models with variable input parameters by perturbation methods

“…In contrast to [4][5][6][7], the proposed method of "perturbations" applied to the model of inventory management is the development of analytical tools for procurement management and inventory logistics. In particular, the proposed asymptotic formulas make it possible to model the inventory management system of the enterprise under the condition of variable order fulfillment and inventory storage costs, as well as take into account fluctuations in demand for goods and services offered by the company in the market.…”

“…Perturbation methods are used: -in mechanics of solid structures (for example, solution of the problem of stability of a circular cylindrical shell of variable thickness under axial compression was developed in [4] with the help of asymptotic approach; a variant derivation of the changed Bress-Tymoshenko equations with the asymptotic approach was offered in [5]); -in differential equations. For example, the perturbation method was applied in [6] to the problem of vibration of a piezoelectric sandwich plate taking into account the effect of shear force. A hybrid method based on a combination of analytical asymptotic WKB approach and numerical Galerkin method was used in [7].…”

Fabrication and performance of PNN-PZT piezoelectric ceramics obtained by low-temperature sintering

“…With the rapid development of the electronic information technology, the electronic components widely applied in various devices, such as transformers, reproducers and fil-ters, trend to be smaller, lighter and cheaper [1][2][3]. As the most popular lead-based piezoelectric ceramic, The PNN-PZT system with excellent piezoelectric constant, high electromechanical coupling factor and eminent permittivity are widely used both in military and civilian applications [4,5].…”

An Aproximate Analytical Solution for Nonlinear FGM Shell Structure With Variable in Time Parameters

“…The present research devoted to an approximate analytical solution of nonlinear dynamic problem of FGM imperfect shallow shells with time dependent parameters (for example, with thickness depending on time) on the basis of hybrid (P-WKB-G) asymptotic method, which was successfully applied in some mechanical problems [5][6][7][8][9][10][11]15]. …”