Seminars given by

Prof. STUART S. ANTMAN

 organized by the Pál Csonka PhD School in the framework of the project

TÁMOP-4.2.2/B-10/1-2010-0009

 Thresholds in nonlinear material behavior

18th September 2012 at 16:00

Budapest University of Technology and Economics, central building, Room K354/a

 Abstract:

By treating large classes of nonlinear constitutive equations for a given problem one can often find thresholds in material response that separate qualitatively distinct dynamical behaviors of solutions. This lecture presents several such examples of concrete problems exhibiting thresholds for materials with nonlinearly elastic, viscous, and other responses. Some thresholds separate situations that are dangerous from those that are not. Thresholds, dangerous or not, correspond to nongeneric behavior for differential equations.

 Exact equations for extensible strings:

formulation, problems, and analysis

26th September 2012 at 11:00

Eötvös Loránd University, Northern building, Novobátzky Room É 2.54

 Abstract:

This lecture presents a simple derivation of the exact equations of motion of extensible (nonlinearly elastic and viscoelastic) strings undergoing large 3-dimensional motions, with a pause to show how the classical equations for infinitesimal transverse vibrations can be systematically obtained. The lecture then outlines the analyses of a few nonlinear problems of equilibrium and motion. The lecture ends with a discussion of the critical role of bending stiffness in embedding string theories within richer theories.