This work introduces a novel streamline seeding technique based on dual streamlines that are orthogonal to the vector field, instead of tangential. The greedy algorithm presented here produces a net of orthogonal streamlines that is iteratively refined resulting in good domain coverage and a high degree of continuity and uniformity. The algorithm is easy to implement and efficient, and it natur...

Fiber tracking is a standard tool to estimate the course of major white matter tracts from diffusion tensor magnetic resonance imaging (DT-MRI) data. In this work, we aim at supporting the visual analysis of classical streamlines from fiber tracking by integrating context from anatomical data, acquired by a T1-weighted MRI measurement. To this end, we suggest a novel visualization metaphor, whi...

Topological groundwater hydrodynamics is an emerging subdiscipline in the mechanics of ¯uids in porous media whose objective is to investigate the invariant geometric properties of subsurface ¯ow and transport processes. In this paper, the topological characteristics of groundwater ¯ows governed by the Darcy law are studied. It is demonstrated that: (i) the topological constraint of zero helici...

We introduce a novel, automatic streamline seeding algorithm for vector fields defined on surfaces in 3D space. The algorithm generates evenly spaced streamlines fast, simply and efficiently for any general surface-based vector field. It is general because it handles large, complex, unstructured, adaptive resolution grids with holes and discontinuities, does not require a parametrization, and c...

Diffusion MR data sets produce large numbers of streamlines which are hard to visualize, interact with, and interpret in a clinically acceptable time scale, despite numerous proposed approaches. As a solution we present a simple, compact, tailor-made clustering algorithm, QuickBundles (QB), that overcomes the complexity of these large data sets and provides informative clusters in seconds. Each...

We consider mixing via chaotic advection in microdroplets suspended at the free surface of a liquid substrate and driven along a straight line using the thermocapillary effect. With the help of a model derived by Grigoriev Phys. Fluids 17, 033601 2005 we show that the mixing properties of the flow inside the droplet can vary dramatically as a function of the physical properties of the fluids an...

Diffusion tensor imaging (DTI) is a relatively new imaging technique which is used to measure the water diffusion in the brain. Since water diffusion is influenced by the micro-structure of tissue DTI can be used to identify nerve fibre tracts in the brain. Over recent years many fibre tracking techniques have been proposed, but little work has been done to evaluate and compare these techniques...

This paper explains the basic steps form the classical turbulence mechanics (CTM) to the postclassical turbulence mechanics (PCTM). When the CTM stems from the characterization of the motion states in the infinitesimal surroundings of the flow-field points by the flow velocity at these points then the PCTM complements this characterization by the curvature of the velocity fluctuation streamline...

Several methods have been proposed for representing vector fields (glyphs, particles, icons, Streamlines, Hyperstreamlines, Spot Noise, LIC, etc.), being streamlines and LIC the two most important. In previous work we already discussed thoroughly the advantages and drawbacks of these methods, and proposed a new, parametrized method that combines successfully the good properties of both. In this...

The flow field around a sphere falling at its terminal velocity in a column of viscoelastic non-shear-thinning fluid is experimentally measured with digital particle image velocimetry. The working fluid is an extensively characterized, monodisperse, polystyrene based Boger fluid. The sphere radius relative to the radius of the column of fluid is small (a/rc50.083). The Weissenberg number (lUt /...