In this paper we present a novel and efficient depth-image representation and warping technique called DMesh which is based on a piece-wise linear approximation of the depth-image as a textured and simplified triangle mesh. We describe the application of a hierarchical multiresolution triangulation method to generate adaptively triangulated depth-meshes efficiently from reference depth-images, ...

This paper proposes object-based moving visual representations for quick browsing of video content. These representations are hierarchical, such that at the coarse level a sequence of alpha planes provides a moving representation of object shape and motion information for object contours. Alternatively, a 2D mesh representation provides a complete visual representation of object mot ion and sha...

3D laser range sensors provide range data of objects in a scene. Most of the known approaches for object recognition and localization in range data try to extract features and determine the position of the object from this information. In opposite we create a virtual scene, make a virtual range image with a virtual 3D laser range sensor and compare the result with range data of the real 3D lase...

This report describes the realization of a geometry kernel and user interface for the purpose of constructing parameterized 2-manifold surfaces, smoothing them with Catmull-Clark subdivision, and offsetting them to generate models that are physically realizable on rapid-prototyping machines. The main focus is to make these operations working robustly also on single-sided, non-orientable 2-manif...

This paper discusses adaptive finite element methods for the solution of elliptic eigenvalue problems associated with partial differential operators. An adaptive method based on nodalpatch refinement leads to an asymptotic error reduction property for the computed sequence of simple eigenvalues and eigenfunctions. This justifies the use of the proven saturation property for a class of reliable ...

This paper presents a novel approach for multi-organ (musculoskeletal system) automatic registration and segmentation from clinical MRI datasets, based on discrete deformable models (simplex meshes). We reduce the computational complexity using multi-resolution forces, multi-resolution hierarchical collision handling and large simulation time steps (implicit integration scheme), allowing real-t...

We present optimal order preconditioners for certain discontinuous Galerkin (DG) finite element discretizations of elliptic boundary value problems. A specific assembling process is proposed which allows us to use the hierarchy of geometrically nested meshes. We consider two variants of hierarchical splittings and study the angle between the resulting subspaces. Applying the corresponding two-l...

We present a straightforward microfluidics system to achieve step-by-step reaction sequences in a diffusion-controlled manner in quasi two-dimensional micro-confinements. We demonstrate the hierarchical self-organization of actin (actin monomers-entangled networks of filaments-networks of bundles) in a reversible fashion by tuning the [Formula: see text] ion concentration in the system. We show...

Finite element modelling of three dimensional elasticity problems gives rise to large sparse matrices. Various preconditioning methods are developed for use in preconditioned conjugate gradient iterative solution techniques. Incomplete factorizations based on levels of fill, drop tolerance, and a two level hierarchical basis are developed. Various techniques for ensuring that the incomplete fac...

This report presents a voxel-based biomechanical model for muscle deformation using nite element method (FEM) and volume graphics. Hierarchical voxel meshes are reconstructed from ltered segmented muscle images followed by FEM simulation and volume rendering. Physiological muscle force is considered and linear elastic muscle models for both static and dynamic cases are simulated by FEM. Voxel-b...