Asymptotic Theory Of Dynamic Boundary Value Problems In Irregular Domains

Asymptotic Theory of Dynamic Boundary Value Problems in Irregular Domains

This book considers dynamic boundary value problems in domains with singularities of two types. The first type consists of "edges" of various dimensions on the boundary; in particular, polygons, cones, lenses, polyhedra are domains of this type. Singularities of the second type are "singularly perturbed edges" such as smoothed corners and edges and small holes. A domain with singularities of such type depends on a small parameter, whereas the boundary of the limit domain (as the parameter tends to zero) has usual edges, i.e. singularities of the first type. In the transition from the limit domain to the perturbed one, the boundary near a conical point or an edge becomes smooth, isolated singular points become small cavities, and so on. In an "irregular" domain with such singularities, problems of elastodynamics, electrodynamics and some other dynamic problems are discussed. The purpose is to describe the asymptotics of solutions near singularities of the boundary. The presented results and methods have a wide range of applications in mathematical physics and engineering. The book is addressed to specialists in mathematical physics, partial differential equations, and asymptotic methods.

Analysis of Structures on Elastic Foundation

This book is devoted to the static and dynamic analysis of structures on elastic foundation. Through comprehensive analysis, the book shows analytical and mechanical relationships among classic and modern methods of solving boundary value problems. The book provides a wide spectrum of applications of modern techniques and methods of calculation of static and dynamic problems of engineering design. It pursues both methodological and practical purposes, and the accounting of all methods is accompanied by solutions of the specific problems, which are not merely illustrative in nature but may represent an independent interest in the study of various technical issues. Two special features of the book are the extensive use of the generalized functions for describing the impacts on structures and the substantiations of the methods of the apparatus of the generalized functions. The book illustrates modern methods for solving boundary-value problems of structural mechanics and soil mechanics based on the application of boundary equations. The book presents the philosophy of boundary equations and boundary element methods. A number of examples of solving different problems of static and dynamic calculation of structures on an elastic foundation are given according to the methods presented in the book. Introduces a general approach to the method of integral transforms based on the spectral theory of the linear differential operators. The Spectral Method of Boundary Element (SMBE) is developed based on using integral transforms with an orthogonal kernel in the extended domain. Presents a new, versatile foundation model with a number of advantages over the ground-based models currently used in practical calculations. Provides new transforms which will aid in solving various problems relevant to bars, beams, plates, and shells in particular for the structures on elastic foundation. Examines the methods of solving boundary-value problems typical for structural mechanics and related fields.

Scientific and Technical Aerospace Reports