Marita Thomas

Learn More
In this paper an existence result for energetic solutions of rate-independent damage processes is established and the temporal regularity of the solution is discussed. We consider a body consisting of a physically nonlinearly elastic material undergoing small deformations and partial damage. The present work is a generalization of [MiR06] concerning the(More)
We derive a two-scale homogenization limit for reaction-di usion systems where for some species the di usion length is of order 1 whereas for the other species the di usion length is of the order of the periodic microstructure. Thus, in the limit the latter species will display di usion only on the microscale but not on the macroscale. Because of this(More)
In this paper some analytical and numerical aspects of time-dependent models with internal variables are discussed. The focus lies on elasto/visco-plastic models of monotone type arising in the theory of inelastic behavior of materials. This class of problems includes the classical models of elasto-plasticity with hardening and viscous models of the(More)
This note deals with the analysis of a model for partial damage, where the rate-independent, unidirectional ow rule for the damage variable is coupled with the rate-dependent heat equation, and with the momentum balance featuring inertia and viscosity according to Kelvin-Voigt rheology. The results presented here combine the approach from Roubí£ek [Rou09,(More)
We address the analysis of an abstract system coupling a rate-independent process with a second order (in time) nonlinear evolution equation. We propose suitable weak solution concepts and obtain existence results by passing to the limit in carefully devised time-discretization schemes. Our arguments combine techniques from the theory of gradient systems(More)
We consider a device concept for edge-emitting lasers based on strained germanium (Ge) microstrips. The special SiN stressor design induces an inhomogeneous (tensile) strain distribution and requires lateral current injection. Microscopic calculations of the material gain for strained Ge enter our two-dimensional simulation of the carrier transport and of(More)
  • 1