The work is devoted to the development of methods for controlling efficiency energy transfer in a composite elastic waveguide. Based on analysis scattered field at boundary stepped waveguide, formed by rigid contact two half-layers with same mechanical characteristics, but different thicknesses, main factors that affect transparency interface were established. Harmonic oscillations generated fi...

The purpose of the present retrospective study was to learn the long-term outcome of oral premalignant lesions, leukoplakia and erythroplakia, with or without surgical intervention and to relate the outcome to factors supposed to be significant for malignant development including clinical type, demarcation, size, site, presence of epithelial dysplasia, smoking and surgery. A total of 269 lesion...

This paper is devoted to the study of a hydrodynamical equation of Riemann type, generalizing the remarkable Gurevich–Zybin system. This multi-component non-homogenous hydrodynamic equation is characterized by the only characteristic flow velocity. The compatible bi-Hamiltonian structures and Lax type representations of the 3-and 4-component generalized Riemann type hydrodynamical system are an...

In this paper we introduce projective geometry and one of its important theorems. We begin by defining projective space in terms of homogenous coordinates. Next, we define homgenous curves, and describe a few important properties they have. We then introduce Bezout’s Theorem, which asserts that the number of intersection points of two homogenous curves is less than or equal to the product of th...