Transformations of discrete isothermic nets and discrete cmc-1 surfaces in hyperbolic space

Using a quaternionic calculus, the Christoffel, Darboux, Goursat, and spectral transformations for discrete isothermic nets are described, with their interrelations. The Darboux and spectral transformations are used to define discrete analogs for cmc-1 surfaces in hyperbolic space and to obtain a discrete version of Bryant's Weierstrass type representation. Received: 13 September 1999 / Revised version: 27 March 2000     

Lie geometry of linear Weingarten surfaces

We show how linear Weingarten surfaces appear as special Ω-surfaces and give a characterization of those linear Weingarten surfaces that allow a Weierstrass type representation.     

Numerical investigations on the fixation of cemented and uncemented endoprostheses

In this contribution, a constitutive model adopted from the computational plasticity-models of Drucker-Prager and von Mises is presented. This model captures the material behavior of osseointegration and the curing-process of bone cement. With this basic model, both simulations of bone-ingrowth of uncemented implants and simulations of the curing process of bone cement for cemented implants are carried out in a bone-implant interface. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)