@article{KaehlerSimonHege2003, author = {K{\"a}hler, Ralf and Simon, Mark and Hege, Hans-Christian}, title = {Interactive Volume Rendering of Large Data Sets Using Adaptive Mesh Refinement Hierarchies}, volume = {9}, journal = {IEEE Transactions on Visualization and Computer Graphics}, number = {3}, doi = {10.1109/TVCG.2003.1207442}, pages = {341 -- 351}, year = {2003}, language = {en} } @article{KaehlerHege2002, author = {K{\"a}hler, Ralf and Hege, Hans-Christian}, title = {Texture-based volume rendering of adaptive mesh refinement data}, volume = {18}, journal = {The Visual Computer}, number = {8}, pages = {491 -- 492}, year = {2002}, language = {en} } @inproceedings{HegeHutanuKaehleretal.2003, author = {Hege, Hans-Christian and Hutanu, Andrei and K{\"a}hler, Ralf and Merzky, Andr{\´e} and Radke, Thomas and Seidel, Edward and Ullmer, Brygg}, title = {Progressive Retrieval and Hierarchical Visualization of Large Remote Data}, booktitle = {Proceedings of the 2003 Workshop on Adaptive Grid Middleware}, pages = {60 -- 72}, year = {2003}, language = {en} } @article{HegeKaehlerSeideletal.2002, author = {Hege, Hans-Christian and K{\"a}hler, Ralf and Seidel, Edward and Radke, Thomas}, title = {GriKSL zeigt Live-Demos auf der iGrid2002}, journal = {DFN-Mitteilungen, Heft 60}, pages = {21 -- 22}, year = {2002}, language = {en} } @inproceedings{KaehlerCoxPattersonetal.2002, author = {K{\"a}hler, Ralf and Cox, Donna and Patterson, Robert and Levy, Stuart and Hege, Hans-Christian and Abel, Tom}, title = {Rendering The First Star in The Universe - A Case Study}, booktitle = {Proceedings of IEEE Visualization 2002}, editor = {J. Moorhead, Robert and Gross, Markus and I. Joy, Kenneth}, publisher = {IEEE Computer Society Press}, address = {Boston MA, USA}, doi = {10.1109/VISUAL.2002.1183824}, pages = {537 -- 540}, year = {2002}, language = {en} } @misc{KaehlerHege2003, author = {K{\"a}hler, Ralf and Hege, Hans-Christian}, title = {Visualization of Time-Dependent Adaptive Mesh Refinement Data}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-7384}, number = {03-16}, year = {2003}, abstract = {Analysis of phenomena that simultaneously occur on quite different spatial and temporal scales require adaptive, hierarchical schemes to reduce computational and storage demands. For data represented as grid functions, the key are adaptive, hierarchical, time-dependent grids that resolve spatio-temporal details without too much redundancy. Here, so-called AMR grids gain increasing popularity. For visualization and feature identification/tracking, the underlying continuous function has to be faithfully reconstructed by spatial and temporal interpolation. Well designed interpolation methods yield better results and help to reduce the amount of data to be stored. We address the problem of temporal interpolation of AMR grid data, e.g.\ for creation of smooth animations or feature tracking. Intermediate grid hierarchies are generated by merging the cells on all refinement levels that are present in the key frames considered. Utilizing a clustering algorithm a structure of nested grids is induced on the resulting collection of cells. The grid functions are mapped to the intermediate hierarchy, thus allowing application of appropriate interpolation techniques.}, language = {en} } @misc{HegeHutanuKaehleretal.2003, author = {Hege, Hans-Christian and Hutanu, Andrei and K{\"a}hler, Ralf and Merzky, Andr{\´e} and Radke, Thomas and Seidel, Edward and Ullmer, Brygg}, title = {Progressive Retrieval and Hierarchical Visualization of Large Remote Data}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-7623}, number = {03-40}, year = {2003}, abstract = {\noindent The size of data sets produced on remote supercomputer facilities frequently exceeds the processing capabilities of local visualization workstations. This phenomenon increasingly limits scientists when analyzing results of large-scale scientific simulations. That problem gets even more prominent in scientific collaborations, spanning large virtual organizations, working on common shared sets of data distributed in Grid environments. In the visualization community, this problem is addressed by distributing the visualization pipeline. In particular, early stages of the pipeline are executed on resources closer to the initial (remote) locations of the data sets. \noindent This paper presents an efficient technique for placing the first two stages of the visualization pipeline (data access and data filter) onto remote resources. This is realized by exploiting the ``extended retrieve'' feature of GridFTP for flexible, high performance access to very large HDF5 files. We reduce the number of network transactions for filtering operations by utilizing a server side data processing plugin, and hence reduce latency overhead compared to GridFTP partial file access. The paper further describes the application of hierarchical rendering techniques on remote uniform data sets, which make use of the remote data filtering stage.}, language = {en} } @inproceedings{KaehlerAbelHege2007, author = {K{\"a}hler, Ralf and Abel, Tom and Hege, Hans-Christian}, title = {Simultaneous GPU-Assisted Raycasting of Unstructured Point Sets and Volumetric Grid Data}, booktitle = {Proceedings of IEEE/EG International Symposium on Volume Graphics 2007}, publisher = {A K Peters}, address = {Prague, Czech Republic}, pages = {49 -- 56}, year = {2007}, language = {en} } @article{AlonsoKaehlerSMikhailovetal.2004, author = {Alonso, Sergio and K{\"a}hler, Ralf and S. Mikhailov, Alexander and Sagu{\´e}s, Francisco}, title = {Expanding scroll rings and negative tension turbulence in a model of excitable media}, volume = {70}, journal = {Phys. Rev. E}, number = {5}, publisher = {American Physical Society}, doi = {10.1103/PhysRevE.70.056201}, pages = {056201}, year = {2004}, language = {en} } @inproceedings{ProhaskaHutanuKaehleretal.2004, author = {Prohaska, Steffen and Hutanu, Andrei and K{\"a}hler, Ralf and Hege, Hans-Christian}, title = {Interactive exploration of large remote micro-CT scans}, booktitle = {Proc. IEEE Visualization 2004}, address = {Austin, Texas}, doi = {10.1109/VIS.2004.51}, pages = {345 -- 352}, year = {2004}, language = {en} }