TY - JOUR A1 - Reininghaus, Jan A1 - Kotava, N. A1 - Günther, David A1 - Kasten, Jens A1 - Hagen, Hans A1 - Hotz, Ingrid T1 - A Scale Space Based Persistence Measure for Critical Points in 2D Scalar Fields JF - Visualization and Computer Graphics, IEEE Transactions on Y1 - 2011 U6 - https://doi.org/10.1109/TVCG.2011.159 VL - 17 IS - 12 SP - 2045 EP - 2052 ER - TY - JOUR A1 - Kasten, Jens A1 - Reininghaus, Jan A1 - Hotz, Ingrid A1 - Hege, Hans-Christian A1 - Noack, Bernd A1 - Daviller, Guillaume A1 - Morzyński, Marek T1 - Acceleration feature points of unsteady shear flows JF - Archives of Mechanics N2 - A framework is proposed for extracting features in 2D transient flows, based on the acceleration field to ensure Galilean invariance. The minima of the acceleration magnitude, i.e. a superset of the acceleration zeros, are extracted and discriminated into vortices and saddle points --- based on the spectral properties of the velocity Jacobian. The extraction of topological features is performed with purely combinatorial algorithms from discrete computational topology. The feature points are prioritized with persistence, as a physically meaningful importance measure. These features are tracked in time with a robust algorithm for tracking features. Thus a space-time hierarchy of the minima is built and vortex merging events are detected. The acceleration feature extraction strategy is applied to three two-dimensional shear flows: (1) an incompressible periodic cylinder wake, (2) an incompressible planar mixing layer and (3) a weakly compressible planar jet. The vortex-like acceleration feature points are shown to be well aligned with acceleration zeros, maxima of the vorticity magnitude, minima of pressure field and minima of λ2. Y1 - 2016 VL - 68 IS - 1 SP - 55 EP - 80 ER - TY - CHAP A1 - Kasten, Jens A1 - Zoufahl, Andre A1 - Hege, Hans-Christian A1 - Hotz, Ingrid T1 - Analysis of Vortex Merge Graphs T2 - VMV 2012: Vision, Modeling and Visualization Y1 - 2012 U6 - https://doi.org/10.2312/PE/VMV/VMV12/111-118 SP - 111 EP - 118 PB - Eurographics Association ER - TY - CHAP A1 - Auer, Cornelia A1 - Kasten, Jens A1 - Kratz, Andrea A1 - Zhang, Eugene A1 - Hotz, Ingrid T1 - Automatic, Tensor-Guided Illustrative Vector Field Visualization T2 - Proc. IEEE Pacific Visualization Symposium 2013 Y1 - 2013 U6 - https://doi.org/10.1109/PacificVis.2013.6596154 SP - 265 EP - 275 CY - Sydney, Australia ER - TY - JOUR A1 - Hege, Hans-Christian A1 - Kasten, Jens A1 - Hotz, Ingrid T1 - Distillation and Visualization of Spatiotemporal Structures in Turbulent Flow Fields JF - J. Phys. Y1 - 2011 U6 - https://doi.org/10.1088/1742-6596/318/6/062009 VL - 318 SP - 062009 ET - 6 ER - TY - JOUR A1 - Reininghaus, Jan A1 - Kasten, Jens A1 - Weinkauf, Tino A1 - Hotz, Ingrid T1 - Efficient Computation of Combinatorial Feature Flow Fields JF - Transactions on Visualization and Computer Graphics Y1 - 2012 U6 - https://doi.org/10.1109/TVCG.2011.269 VL - 18 IS - 9 SP - 1563 EP - 1573 ER - TY - CHAP A1 - Kasten, Jens A1 - Weinkauf, Tino A1 - Petz, Christoph A1 - Hotz, Ingrid A1 - Noack, Bernd R. A1 - Hege, Hans-Christian T1 - Extraction of Coherent Structures from Natural and Actuated Flows T2 - Active Flow Control II Y1 - 2010 SN - 978-3-642-11734-3 U6 - https://doi.org/10.1007/978-3-642-11735-0_24 VL - 108 SP - 373 EP - 387 PB - Springer, Berlin ER - TY - GEN A1 - Kasten, Jens A1 - Reininghaus, Jan A1 - Oberleithner, Kilian A1 - Hotz, Ingrid A1 - Noack, Bernd A1 - Hege, Hans-Christian T1 - Flow over a Cavity – Evolution of the Vortex Skeleton Y1 - 2010 PB - Visualization at 28th Annual Gallery of Fluid Motion exhibit, held at the 63th Annual Meeting of the American Physical Society, Division of Fluid Dynamics (Long Beach, CA, USA, November 21-23, 2010). ER - TY - JOUR A1 - Petz, Christoph A1 - Kasten, Jens A1 - Prohaska, Steffen A1 - Hege, Hans-Christian T1 - Hierarchical Vortex Regions in Swirling Flow JF - Computer Graphics Forum Y1 - 2009 VL - 28 IS - 3 SP - 863 EP - 870 ER - TY - THES A1 - Kasten, Jens T1 - Lagrangian feature extraction in two-dimensional unsteady flows Y1 - 2012 ER -