@conference {806,
	title = {Analysis of coupled thermo-hydro-mechanical simulations of a generic nuclear waste repository in clay rock using fiber surfaces},
	booktitle = {IEEE Pacific Visualization Symposium (PacificVis 2019)},
	year = {2019},
	address = {Bangkok},
	abstract = {The use of clean and renewable energy and the abandoning of fossil energy have become goals of many national and international energy policies. But even when once accomplished, mankind has to take charge of the relics of the current energy supply system. For example, due to its harmful effects, nuclear waste has to be isolated from the biosphere safely and for sufficiently long times. The geological subsurface is considered as a promising option for the deposition of such by- or end products. In order to investigate the long-term evolution of a repository system, a multiphysics simulation was performed. It combines the structural mechanics of the host rock, the fluid dynamics of formation fluids, and the thermodynamics of all materials resulting in a highly multivariate data set. A visualization of such multiphysics data challenges the current methodology. In this article, we demonstrate how an analysis of a carefully selected subset of the variables in attribute space allows to visualize and interpret the simulation data. We apply a fiber surface extraction algorithm to explore the relationships between these variables. Studying the temporal evolution in attribute space, we found a regionally bulge that could be identified as an effect of the nuclear waste repository because it can be clearly separated from the natural geophysical state prior to waste disposal. Furthermore, we used the extracted fiber surface as a starting point to examine the distribution of other variables inside this area of the physical domain. We conclude this case study with lessons learned from the visualization as well as the geotechnical side.},
	author = {Christian Blecha and Felix Raith and Gerik Scheuermann and Thomas Nagel and Olaf Kolditz and Jobst Ma{\ss}mann}
}
@article {786,
	title = {Tensor Field Visualization using Fiber Surfaces of Invariant Space},
	journal = {IEEE Transactions on Visualization and Computer Graphics},
	volume = {25},
	year = {2018},
	month = {01/2019},
	pages = {1122-1131},
	chapter = {1122},
	abstract = {Scientific visualization developed successful methods for scalar and vector fields. For tensor fields, however, effective, interactive visualizations are still missing despite progress over the last decades. We present a general approach for the generation of separating surfaces in symmetric, second-order, three-dimensional tensor fields. These surfaces are defined as fiber surfaces of the invariant space, i.e. as pre-images of surfaces in the range of a complete set of invariants. This approach leads to a generalization of the fiber surface algorithm by Klacansky et al. [16] to three dimensions in the range. This is due to the fact that the invariant space is three-dimensional for symmetric second-order tensors over a spatial domain. We present an algorithm for surface construction for simplicial grids in the domain and simplicial surfaces in the invariant space. We demonstrate our approach by applying it to stress fields from component design in mechanical engineering.},
	keywords = {fiber surface, Geometry, interaction, invariants, Mechanical engineering, Neuroscience, Strain, Tensile stress, tensor field, Visualization},
	issn = {1077-2626},
	doi = {10.1109/TVCG.2018.2864846},
	url = {https://ieeexplore.ieee.org/document/8447439},
	author = {Felix Raith and Christian Blecha and Thomas Nagel and Francesco Parisio and Olaf Kolditz and Fabian G{\"u}nther and Markus Stommel and Gerik Scheuermann}
}
