The electromagnetic eld of the ultrarelativistic Reissner Nordstrrm Solution shows the physically highly unsatisfactory property of a vanishing eld tensor but a nonzero, i.e.-like, energy density. The aim of this work is to analyse this situation from a mathematical point of view, using the framework of Colombeau's theory of nonlinear generalized functions. It is shown that the physically unsat...

Abstract In this work, mathematical models of physically nonlinear plates and beams made from multimodulus materials are constructed. Our considerations based on the 3D deformation theory plasticity, von Mises plasticity criterion method variable parameters elasticity developed by Birger. The proposed computational algorithm enable for solving problems three types boundary conditions, edge cond...

A comprehensive physical model of adiabatic three-wave mixing is developed for the fully nonlinear regime, i.e., without making the undepleted pump approximation. The conditions for adiabatic evolution are rigorously derived, together with an estimate of the bandwidth of the process. Furthermore, these processes are shown to be robust and efficient. Finally, numerical simulations demonstrate ad...

1. Differential-Difference Equations Dating back to the work of Fermi, Pasta, and Ulam in the 1950’s [2] differential-difference equations (DDEs) have been the focus of many nonlinear studies. A number of physically interesting problems can be modeled with nonlinear DDEs, including particle vibrations in lattices, currents in electrical networks, pulses in biological chains, etc. DDEs play impo...

Films like Shrek, Madagascar, The Chronicles of Narnia and Charlotte’s web all have something in common: realistic quadruped animations. While the animation of animals has been popular for a long time, the technical challenges associated with creating highly realistic, computer generated creatures have been receiving increasing attention recently. The entertainment, education and medical indust...

A static mixed boundary value problem of physically nonlinear elasticity for a continuously inhomogeneous body is considered. Using the two-operator Green-Betti formula and the fundamental solution of an auxiliary linear operator, a non-standard boundary-domain integro-differential formulation of the problem is presented, with respect to the displacements and their gradients. Using a cut-off fu...

Nonlinear grey-box identification of industrial robots is considered. A three-step identification procedure is proposed in which parameters for rigid body dynamics, friction, and flexibilities can be identified only using measurements on the motor. In the first two steps, good initial parameter estimates are derived which are used in the last step, where the parameters of a nonlinear physically...