A flat, compressed elastic film on a viscous layer is unstable. The film can form wrinkles to reduce the elastic energy. A linear perturbation analysis is performed to determine the critical wave number and the growth rate of the unstable modes. While the viscous layer has no effect on the critical wave number, its viscosity and thickness set the time scale for the growth of the perturbations. ...

The mechanical properties of hydrogen-bonded layer-by-layer (LbL) microcapsule shells constructed from tannic acid (TA) and poly(vinylpyrrolidone) (PVPON) components have been studied in both the dry and swollen states. In the dry state, the value of the elastic modulus was measured to be within 0.6-0.7 GPa, which is lower than the typical elastic modulus for electrostatically assembled LbL she...

A new perfectly matched layer (PML) for the simulation of elastic waves in anisotropic media on an unbounded domain is constructed. Theoretical and numerical results, showing that the stability properties of the present layer are better than previously suggested layers, are presented. In addition, the layer can be formulated with fewer auxiliary variables than the split-field PML.

We examine the elastic shear waves generated in a thin pre-stressed elastomer layer that is sandwiched between two relatively thick steel plates and is subjected to an elastic shear wave traveling in one of the steel plates. The elastomer layer has been deformed in uni-axial strain in advance, producing in the layer very large axial and lateral compressive stresses of the order of its bulk modu...

A compressively strained elastic film bonded to a viscous layer can form wrinkles. The present study provides a theoretical model for the wrinkling process. The elastic film is modeled with the nonlinear theory of a thin plate subject to in-plane and out-of-plane loads. The flow of the viscous layer is modeled with the theory of lubrication. The interface between the elastic film and the viscou...

In this research in numerical analysis software packages SIGMA / W based on the finite element method was to have been used. For this purpose, during the construction of the dam Kaboodval using behavioral models elastic - plastic and elastic non-homogeneous, non-linear elastic, linear elastic been analyzed and pore pressure, stresses in the body and its meeting with the Data Tools the compariso...

BACKGROUND The physical characteristics of bandage kits, in which different materials are combined, cannot be predicted by laboratory tests. They can only be assessed in vivo by measuring the interface pressure and calculation of stiffness. OBJECTIVE The objective was to investigate pressure and stiffness of some widely used multicomponent, multilayer bandages and to investigate the effect of...

Concerning the structure of connective-muscular components the authors studied the walls of the terminal segments of the vertebral arteries as well as the basilar artery, utilizing the following staining methods: Azan modified by Heidenheim, Weigert's resorcin-fuchsin, and Weigert modified by van Gieson. It was established that wall of the vertebro-basilar system exhibits a mixed structure, mus...