Flows Generating Nonlinear Eigenfunctions

Flows Generating Nonlinear Eigenfunctions

Nonlinear variational methods have become very powerful tools for many image processing tasks. Recently a new line of research has emerged, dealing with nonlinear eigenfunctions induced by convex functionals. This has provided new insights and better theoretical understanding of convex regularization and introduced new processing methods. However, the theory of nonlinear eigenvalue problems is ...

Ferreira : Nonlinear Systems and Exponential Eigenfunctions

Analysis of turbulent flows by means of the empirical eigenfunctions

The method of empirical eigenfunctions is developed in a general framework. In particular it is shown that the method of snapshots leads to the determination of the empirical eigenfunctions in any number of dimensions in terms of an equivalent one-dimensional problem. The methodology is discussed within the framework of some turbulent simulations and it is shown how this facilitates the flow an...

2DV Nonlinear k-ε Turbulence Modeling of Stratified Flows

The commonly used linear k-ε turbulence model is shown to be incapable of accurate prediction of turbulent flows, where non-isotropy is dominant. Two examples of non-isotropic flows, which have a wide range of applications in marine waters, are saline water flow and the stratified flows due to temperature gradients. These relate to stratification and consequently, variation of density through...

Generating Geodesic Flows and Supergravity Solutions

We consider the geodesic motion on the symmetric moduli spaces that arise after timelike and spacelike reductions of supergravity theories. The geodesics correpond to timelike respectively spacelike p-brane solutions when they are lifted over a pdimensional flat space. In particular, we consider the problem of constructing the minimal generating solution: A geodesic with the minimal number of f...