@book{peikert12topological,
  author = {Ronald Peikert and Helwig Hauser and Hamish Carr and Raphael Fuchs},
  title = {Topological Methods in Data Analysis and Visualization II: Theory, 
    Algorithms, and Applications},
  year = {2012}, 
  series = {Mathematics and Visualization},
  abstract = {
   When scientists analyze datasets in a search for underlying phenomena, patterns 
   or causal factors, their first step is often an automatic or semi-automatic search 
   for structures in the data. Of these feature-extraction methods, topological ones 
   stand out due to their solid mathematical foundation. Topologically defined 
   structures -as found in scalar, vector and tensor fields- have proven their merit 
   in a wide range of scientific domains, and scientists have found them to be 
   revealing in subjects such as physics, engineering, and medicine.
   Full of state-of-the-art research and contemporary hot topics in the subject, this
   volume is a selection of peer-reviewed papers originally presented at the fourth 
   Workshop on Topology-Based Methods in Data Analysis and Visualization, TopoInVis 
   2011, held in Zurich, Switzerland. The workshop brought together many of the leading 
   lights in the field for a mixture of formal presentations and discussion. One topic 
   currently generating a great deal of interest, and explored in several chapters here, 
   is the search for topological structures in time-dependent flows, and their relationship 
   with Lagrangian coherent structures. Contributors also focus on discrete topologies 
   of scalar and vector fields, and on persistence-based simplification, among other 
   issues of note. The new research results included in this volume relate to all 
   three key areas in data analysis�theory, algorithms and applications.},
  publisher = {Springer},
  images = {images/peikert12topological.png},
  thumbnails = {images/peikert12topological_thumb.png},
  isbn = {978-3-642-23175-9},
  URL = {http://www.springer.com/mathematics/computational+science+%26+engineering/book/978-3-642-23174-2},
}

@phdthesis{solteszova12thesis,
  title = {Perception-Augmenting Illumination},
  author = {Veronika \v{S}olt{\'e}szov{\'a}},
  year = {2012},
  month = {Aug},
  abstract = {At each stage of the visualization pipeline, the information is impeded 
  by loss or by noise because of imprecise acquisition, storage limitations, and 
  processing. Furthermore, it passes through the complex and not yet well understood 
  pathways in the human visual system and finally to result into a mental image. Due 
  to the noise that impedes the information in the visualization pipeline and the 
  processes in the human visual system, the mental image and the real-world phenomenon
  do not match. From the aspect of physics, the input of the visual system is confined 
  only to patterns of light. Illumination is therefore essential in 3D visualization 
  for perception of visualized objects. In this thesis, several advancements for advanced 
  volumetric lighting are presented. First, a novel lighting model that supports 
  interactive light source placement and yields a high-quality soft shadowing effect, 
  is proposed. The light transport is represented by conical functions and approximated 
  with an incremental blurring operation of the opacity buffer during front-to-back 
  slicing of the volume. Furthermore, a new perceptuallyfounded model for expressing 
  shadows that gives a full control over the appearance of shadows in terms of color 
  and opacity, is presented. Third, a systematic error in perception of surface slant 
  is modeled. This knowledge is then applied to adjust an existing shading model in a 
  manner that compensates for the error in perception. These new visualization
  methodologies are linked to the knowledge of perceptual psychology and the
  craft of illustrators, who experimented with visual-presentation techniques for centuries.
  The new methodologies are showcased on challenging acoustic modalities such as 3D
  medical ultrasound and sonar imaging.},
  school = {Department of Informatics, University of Bergen, Norway},
  ISBN = {978-82-308-2118-3},
  images = {images/solteszova12thesis.png},
  thumbnails = {images/solteszova12thesis_thumb.png},
  pdf = {pdfs/solteszova12thesis.pdf},
}


@phdthesis{angelelli12thesis,
  title = {Visual Exploration of Human Physiology:
            Visualizing Perfusion, Blood Flow and Aging},
  author = {Paolo Angelelli},
  year = {2012},
  abstract = {With the technological advancements in medical imaging, it is nowadays
possible to capture in-vivo information related to different human physiological
systems. Such data extends the more traditional anatomical scans,
but add size, complexity and heterogeneity. In addition, while anatomy
data is defined in three-dimensional space, and 3D graphics techniques can
be used to represent it on the screen, physiology information is often more
abstract, and require tailored solutions to be represented in combination
with their anatomical context.
This thesis presents solutions for visualizing selected aspects in three
domains of physiology: blood flow, perfusion and aging. With respect to
blood flow, it includes a technique to enhance the side-by-side visualization
of the tubular flow in vessels. This result is achieved with a method
that generates straightened visualizations of the flow in its context, which
can be easily aligned and then related to each other. With respect to perfusion,
this thesis includes an interactive visual analysis solution that ease
and improve the exploration, segmentation and analysis of perfusion data
acquired using contrast-enhanced ultrasound. This result is achieved by
using a statistical framework to extract enhancement information, and an
interactive, correlation-based approach to classify the tissue based on similarity.
Finally, with respect to aging, two solutions to help exploring large
data collections of repeated examinations are presented. In one, interactive
visual analysis methods are employed to explore and analyze cohort study
data, while the other focuses on the guided exploration of repeated ultrasound
examinations. Demonstration case studies are include to exemplify
the utility of the presented work.},
  school = {Department of Informatics, University of Bergen, Norway},
  month = {Apr},
  ISBN = {978-82-308-2073-5},
  images = {images/angelelli12thesis.png},
  thumbnails = {images/angelelli12thesis_thumb.png},
  pdf = {pdfs/angelelli12thesis.pdf},
}

@phdthesis{pobitzer12thesis,
  title = {Interactive Visual Analysis of Time-dependent Flows:
            Physics- and Statistics-based Semantics},
  author = {Armin Pobitzer},
  year = {2012},
  month = {Apr},
  abstract = {With the increasing use of numerical simulations in the fluid mechanics
 community in recent years flow visualization increasingly gains importance
 as an advanced analysis tool for the simulation output. Up to now, flow
 visualization has mainly focused on the extraction and visualization of structures
 that are defined by their semantic meaning. Examples for such structures
 are vortices or separation structures between different groups of particles that
 travel together.
 In order to deepen our understanding of structures linked to certain flow phenomena,
 e.g., how and why they appear, evolve, and finally are destroyed, also
 linking structures to semantic meaning that is not attributed to them by their
 very definition, is a highly promising research direction to pursue.
 In this thesis we provide several approaches on how to augment structures
 stemming from classical flow visualization techniques by additional semantic
 information originating from new methods based on physics and statistics. In
 particular, we target separation structures, the linking of structures with a local
 semantics to global flow phenomena, and minimal representation of particle
 dynamics in the context of path line attributes.},
  school = {Department of Informatics, University of Bergen, Norway},
  ISBN = {978-82-308-2063-6},
  url = {https://bora.uib.no/handle/1956/5856}, 
  images = {images/Pobitzer12Physics.png},
  thumbnails = {images/Pobitzer12Physics_thumb.png},
  pdf = {pdfs/pobitzer12thesis.pdf},
}

@inproceedings{Ford12HeartPad,
 author = {Steven Ford and Gabriel Kiss and Ivan Viola and Stefan Brukner and
  Hans Torp},
 title = {HeartPad: Real-Time Visual Guidance for Cardiac Ultrasound},
 booktitle = {Proceedings of Workshop at SIGGRAPH ASIA 2012},
 series = {WASA 2012},
 year = {2012},
 month = {November},
 address = {Fusionopolis, Singapore},
 abstract = {Medical ultrasound is a challenging modality when it comes to image
  interpretation. The goal we address in this work is to assist
  the ultrasound examiner and partially alleviate the burden of interpretation.
  We propose to address this goal with visualization that
  provides clear cues on the orientation and the correspondence between
  anatomy and the data being imaged. Our system analyzes the
  stream of 3D ultrasound data and in real-time identifies distinct features
  that are basis for a dynamically deformed mesh model of the
  heart. The heart mesh is composited with the original ultrasound
  data to create the data-to-anatomy correspondence. The visualization
  is broadcasted over the internet allowing, among other opportunities,
  a direct visualization on the patient on a tablet computer.
  The examiner interacts with the transducer and with the visualization
  parameters on the tablet. Our system has been characterized by
  domain specialist as useful in medical training and for navigating
  occasional ultrasound users.},
 project = {illustrasound,medviz, illvis},
 pdf = {pdfs/Ford12HeartPad.pdf},
 images = {images/Ford12HeartPad01.png, images/Ford12HeartPad02.png},
 thumbnails = {images/Ford12HeartPad01_thumb.png, images/Ford12HeartPad02_thumb.png},
} 


@misc{Brambilla12Geilo,
 author = {Andrea Brambilla and Armin Pobitzer and Helwig Hauser},
 title  ={Flow Visualization and the SemSeg project},
 year = {2012},
 month = {January},
 howpublished = {Poster presented at the Sintef winter school 2012},
 location = {Geilo, Norway},
 url ={http://www.sintef.no/Projectweb/eVITA/Winter-Schools/2012/},
 pdf = {pdfs/Brambilla12Geilo.pdf},
 images = {images/Brambilla12Geilo01.png},
 thumbnails = {images/Brambilla12Geilo01_thumb.png},
}
 

@misc{Hauser12PaVis,
 author = {Helwig Hauser and Stephen G. Kobourov and Huamin Qu},
 title  ={Proceedings of the 2012 IEEE Pacific Visualization Symposium},
 year = {2012},
 month = {February-March},
 howpublished = {Conference proceedings},
 location = {Songdo, Korea},
 url ={http://ieeexplore.ieee.org/xpl/mostRecentIssue.jsp?punumber=6178307},
 images = {images/Helwig12PaVis01.png},
 thumbnails = {images/Helwig12PaVis01.png},
}

@misc{Hauser12VisTutorial,
 author = {Steffen Oeltze and Helmut Doleisch and Helwig Hauser and Gunther Weber},
 title  ={Interactive Visual Analysis of Scientific Data},
 year = {2012},
 month = {October},
 howpublished = {Tutorial at the IEEE VisWeek 2012},
 location = {Seattle (WA), USA},
 abstract = {In a growing number of application areas, a subject or phenomenon is 
  investigated by means of multiple datasets being acquired over time (spatiotemporal), 
  comprising several attributes per data point (multi-variate), stemming from different 
  data sources (multi-modal) or multiple simulation runs (multirun/ensemble). Interactive 
  visual analysis (IVA) comprises concepts and techniques for a user-guided knowledge 
  discovery in such complex data. Through a tight feedback loop of computation, visualization 
  and user interaction, it provides new insight into the data and serves as a vehicle for 
  hypotheses generation or validation. It is often implemented via a multiple coordinated 
  view framework where each view is equipped with interactive drill-down operations for 
  focusing on data features. Two classes of views are integrated: physical views show 
  information in the context of the spatiotemporal observation space while attribute views 
  show relationships between multiple data attributes. The user may drill-down the data by 
  selecting interesting regions of the observation space or attribute ranges leading to a 
  consistent highlighting of this selection in all other views (brushing-and-linking).

  In this tutorial, we discuss examples for successful applications of IVA to scientific 
  data from various fields: automotive engineering, climate research, biology, and medicine.
  We base our discussions on a theoretical foundation of IVA which helps the tutorial 
  attendees in transferring the subject matter to their own data and application area. 
  This universally applicable knowledge is complemented in a tutorial part on IVA of 
  very large data which accounts for the tera- and petabytes being generated by simulations 
  and experiments in many areas of science, e.g., physics, astronomy, and climate research. 
  The tutorial further provides an overview of off-the-shelf IVA solutions. It is concluded 
  by a summary of the gained knowledge and a discussion of open problems in IVA of 
  scientific data.

  The tutorial slides will be available before the conference start date at: 
  <a href="www.vismd.de/doku.php?id=teaching_tutorials:start">www.vismd.de/doku.php?id=teaching_tutorials:start</a>.},
 url ={http://visweek.org/visweek/2012/tutorial/interactive-visual-analysis-scientific-data},
 images = {images/Hauser12VisTutorial.png},
 pres = {pdfs/Hauser12VisTutorialPres01.pdf},
 thumbnails = {images/Hauser12VisTutorial_thumb.png},  
}


@misc{Hauser12VCF,
 author = {Helwig Hauser},
 title = {The Iterative Process of Interactive Visual Analysis},
 year = {2012},
 month = {September},
 howpublished = {Talk in the Visual Computing Forum (VCF) at UiB},
 location = {Bergen, Norway},
 url ={http://www.ii.uib.no/vis/vcf/},
 abstract = {One central characteristic of our information age is 
   that increasingly often we should exploit the wealth of available 
   data for the sake of learning, decision making, as well as other tasks. 
   A promising approach - not at the least also targeted by visual analytics - 
   is to integrate the strengths of computers (fast computation, efficient 
   handling of large datasets, comparably low costs, etc.) with the strengths 
   of the users (perceptual capabilities, considering domain knowledge, 
   detecting the unexpected, etc.). In this talk, we look at one possible 
   solution, i.e., the concept of interactive visual analysis, and describe 
   it as an iterative process, enabling the integration of computational and 
   interactive means for data exploration and analysis. We consider a data 
   scenario that opposes dependent and independent data dimensions (like in 
   a table), general enough to match many different application cases. 
   We focus on the case of multivariate data, but also address the case of 
   high-dimensional data and opportunities for exploring and analyzing such data. 
   After all, we think of interactive visual analysis as an iterative process, 
   where each step is performed on the basis of a toolbox with computational 
   and interactive visual solutions.},
 images = {images/Hauser12VCF.jpg},
 thumbnails = {images/Hauser12VCF_thumb.jpg},
}


@misc{Hauser12TAVA,
 author = {Helwig Hauser},
 title = {Compromises and Added Value in Visual Analytics},
 year = {2012},
 month = {September},
 howpublished = {Keynote talk at the TAVA 2012 workshop},
 location = {Graz, Austria},
 images = {images/Hauser12TAVA.png},
 thumbnails = {images/Hauser12TAVA_thumb.png},
 pres = {pdfs/Hauser12TAVA-slides.pdf}
}

@misc{Hauser12EuroVA,
 author = {Helwig Hauser},
 title = {The Iterative Process of Interactive Visual Analysis},
 year = {2012},
 month = {June},
 howpublished = {Keynote talk at the EuroVA 2012 workshop},
 location = {Vienna, Austria},
 url ={http://www.eurova.org/previous-events/eurova-2012},
 abstract = {One central characteristic of our information age is that increasingly 
 often we should ex�ploit the wealth of available data for the sake of learning, decision 
 making, as well as other tasks.  A promising approach - not at the least also targeted 
 by visual analytics - is to integrate the strengths of computers (fast computation, 
 efficient handling of large datasets, comparably low costs, etc.) with the strengths 
 of the users (perceptual capabilities, considering domain know�ledge, detecting the 
 unexpected, etc.).  In this talk, we look at one possible solution, i.e., the concept 
 of interactive visual analysis, and describe it as an iterative process, enabling the 
 integration of computational and interactive means for data exploration and analysis. 
 We consider a data scenario that opposes dependent and independent data dimensions 
 (like in a table), general enough to match many different application cases.  We focus 
 on the case of multivariate data, but also address the case of high-dimensional data and 
 opportunities for exploring and analyzing such data.  After all, we think of interactive 
 visual analysis as an iterative process, where each step is performed on the basis of a 
 toolbox with computational and interactive visual solutions.},
 images = {images/Hauser12EuroVA.jpg},
 thumbnails = {images/Hauser12EuroVA_thumb.jpg},
 pres = {pdfs/Hauser12EuroVA-pres.pdf}
}

@misc{Hauser12Dagstuhl,
 author = {Helwig Hauser},
 title  ={Automated Methods in Information Visualization},
 year = {2012},
 month = {February},
 howpublished = {Invited talk at the Dagstuhl seminar 12081},
 location = {Wadern, Germany},
 url ={http://www.dagstuhl.de/en/program/calendar/semhp/?semnr=12081},
 abstract = {Visualization and Machine Learning have related goals in terms of helping
  analysts to understand characteristic aspects of data.  While visualization aims
  at involving the user through interactive depictions of data, machine learning
  is generally represented by automatic methods that yield optimal results with
  respect to certain initially specified tasks.  Not at the least within the
  research direction of visual analytics it seems promising to think about
  opportunities to integrate both methodologies in order to exploit the strengths
  of both sides.  Up to now, examples of integration very often encompass the
  visualization of results from automatic methods as well as attempts to make
  originally automated methods partially interactive.  A vision for the future
  would be to integrate interactive and automatic methods in order to solve
  problems.  A possible realization could be an iterative process where the one or
  other approach is chosen on demand at each step.   },
 images = {images/Hauser12Dagstuhl.png},
 thumbnails = {images/Hauser12Dagstuhl_thumb.png},
 pres = {pdfs/Hauser12Dagstuhl-pres.pdf}
}


@misc{Hauser12SemSegWorkshop,
 author = {Helwig Hauser and Kresimir Matkovic},
 title  ={Interactive Visual Analysis of Time-Dependent Flows},
 year = {2012},
 month = {February},
 howpublished = {Presentation at the 3rd SemSeg User Forum Workshop},
 location = {Magdeburg, Germany},
 url ={http://vc.cs.ovgu.de/index.php?article_id=232},
 images = {images/Hauser12SemSegWorkshop.png},
 thumbnails = {images/Hauser12SemSegWorkshop_thumb.png},
 pres = {pdfs/Hauser12SemSegWorkshop-pres.pdf},
 project = {semseg},  
}

@misc{Brambilla12SemSegWorkshop,
 author = {Andrea Brambilla and Robert Carnecky},
 title  ={Introduction to Illustrative Flow Visualization},
 year = {2012},
 month = {February},
 howpublished = {Presentation at the 3rd SemSeg User Forum Workshop},
 location = {Magdeburg, Germany},
 url ={http://vc.cs.ovgu.de/index.php?article_id=232},
 pres = {pdfs/Brambilla12SemSegWorkshop.pdf},
 images = {images/Brambilla12Illustrative.png},
 thumbnails = {images/Brambilla12Illustrative_thumb.png},
 project = {semseg},   
}

@ARTICLE{Doleish12Interactive, 
 author={Helmut Doleisch and Helwig Hauser}, 
 journal={Computing in Science Engineering}, 
 title={Interactive Visual Exploration and Analysis of Multivariate Simulation Data}, 
 year={2012}, 
 month={March-April}, 
 volume={14}, 
 number={2}, 
 pages={70--77}, 
 abstract={The interactive visual exploration of large and complex simulation datasets 
  has become an important methodology that improves data analysis for scientists and 
  professional practitioners.}, 
 keywords={complex simulation datasets;data analysis;important methodology;
  interactive visual exploration;multivariate simulation data;data analysis;
  data visualisation;geophysics computing;}, 
 doi={10.1109/MCSE.2012.27}, 
 ISSN={1521-9615},
 url = {http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6159200},
 images = {images/Doleish12Interactive01.png, images/Doleish12Interactive02.png},
 thumbnails = {images/Doleish12Interactive01_thumb.png, images/Doleish12Interactive02_thumb.png},
 }

@inproceedings{Konyha12Interactive,
 author = {Zoltan Konyha and Alan Lez and Kresimir Matkovic and
  Mario Jelovic and Helwig Hauser},
 title = {Interactive visual analysis of families of curves using data aggregation
  and derivation},
 booktitle = {Proceedings of the 12th International Conference on Knowledge Management
  and Knowledge Technologies},
 series = {i-KNOW '12},
 year = {2012},
 isbn = {978-1-4503-1242-4},
 location = {Graz, Austria},
 pages = {24:1--24:8},
 articleno = {24},
 numpages = {8},
 url = {http://doi.acm.org/10.1145/2362456.2362487},
 doi = {10.1145/2362456.2362487},
 acmid = {2362487},
 publisher = {ACM},
 address = {New York, NY, USA},
 keywords = {attribute derivation, families of curves, interactive visual analysis, 
 knowledge generations},
 images = {images/Konyha12Interactive01.png, images/Konyha12Interactive02.png},
 thumbnails = {images/Konyha12Interactive01_thumb.png, images/Konyha12Interactive02_thumb.png},
} 


@inproceedings{Parulek12Implicit,
 author = {Julius Parulek and Cagatay Turkay and Natalie Reuter and Ivan Viola},
 title = {Implicit Surfaces for Interactive Graph Based Cavity Analysis
   of Molecular Simulations},
 booktitle={2nd IEEE Symposium on Biological Data Visualization},
 series = {BioVis 2012},
 year = {2012},
 location = {Seattle (WA), US},
 abstract = {Molecular surfaces provide a suitable way to analyze and to study
   the evolution and interaction of molecules. The analysis is often
   concerned with visual identification of binding sites of ligands to
   a host macromolecule. We present a novel technique that is based
   on implicit representation, which extracts all potential binding sites
   and allows an advanced 3D visualization of these sites in the con-
   text of the molecule. We utilize implicit function sampling strategy
   to obtain potential cavity samples and graph algorithms to extract
   arbitrary cavity components defined by simple graphs. Moreover,
   we propose how to interactively visualize these graphs in the con-
   text of the molecular surface. We also introduce a system of linked
   views depicting various graph parameters that are used to perform
   a more elaborative study on created graphs.},
 images = {images/Parulek12Implicit01.png, images/Parulek12Implicit02.png},
 thumbnails = {images/Parulek12Implicit01_thumb.png, images/Parulek12Implicit02_thumb.png},
 project = {physioillustration},
 pdf = {pdfs/Parulek12Implicit.pdf},
}


@ARTICLE{Schindler12Lagrangian, 
 author={Benjamin Schindler and Raphael Fuchs and Stefan Barp and Jurgen Waser and
   Armin Pobitzer and Robert Carnecky and Kresimir Matkovic and Ronald Peikert}, 
 journal={Visualization and Computer Graphics, IEEE Transactions on}, 
 title={Lagrangian Coherent Structures for Design Analysis of Revolving Doors}, 
 year={2012}, 
 month={December}, 
 volume={18}, 
 number={12}, 
 pages={2159--2168}, 
 abstract={Room air flow and air exchange are important aspects for the design of 
 energy-efficient buildings. As a result, simulations are increasingly used prior to 
 construction to achieve an energy-efficient design. We present a visual analysis of 
 air flow generated at building entrances, which uses a combination of revolving doors 
 and air curtains. The resulting flow pattern is challenging because of two interacting 
 flow patterns: On the one hand, the revolving door acts as a pump, on the other hand, 
 the air curtain creates a layer of uniformly moving warm air between the interior of 
 the building and the revolving door. Lagrangian coherent structures (LCS), which by 
 definition are flow barriers, are the method of choice for visualizing the separation 
 and recirculation behavior of warm and cold air flow. The extraction of LCS is based 
 on the finite-time Lyapunov exponent (FTLE) and makes use of a ridge definition which 
 is consistent with the concept of weak LCS. Both FTLE computation and ridge extraction 
 are done in a robust and efficient way by making use of the fast Fourier transform for 
 computing scale-space derivatives.}, 
 doi={10.1109/TVCG.2012.243}, 
 ISSN={1077-2626},
 url={http://visdom.at/person/5/},
 images={images/Schindler12Lagrangian01.png},
 thumbnails={images/Schindler12Lagrangian01_thumb.png}, 
}

@inproceedings{Turkay2012DualDNA,
 author = {Cagatay Turkay and Julius Parulek and Helwig Hauser},
 title = {Dual analysis of DNA microarrays},
 booktitle = {Proceedings of the 12th International Conference on Knowledge Management 
  and Knowledge Technologies},
 series = {i-KNOW '12},
 year = {2012},
 location = {Graz, Austria},
 pages = {26:1--26:8},
 articleno = {26},
 numpages = {8},
 keywords = {interactive visual analysis, microarray data, visual analytics},
 abstract = {Microarray data represents the expression levels of genes for different 
 samples and for different conditions. It has been a central topic in bioinformatics 
 research for a long time already. Researchers try to discover groups of genes that
 are responsible for specific biological processes. Statistical analysis tools and
 visualizations have been widely used in the analysis of microarray data. Researchers 
 try to build hypotheses on both the genes and the samples. Therefore, such analyses 
 require the joint exploration of the genes and the samples. However, current methods 
 in interactive visual analysis fail to provide the necessary mechanisms for this joint 
 analysis. In this paper, we propose an interactive visual analysis framework that 
 enables the dual analysis of the samples and the genes through the use of integrated 
 statistical tools. We introduce a set of specialized views and a detailed analysis 
 procedure to describe the utilization of our framework.},
 images = {images/Turkay2012DualDNA01.png, images/Turkay2012DualDNA02.png},
 thumbnails = {images/Turkay2012DualDNA01_thumb.png, images/Turkay2012DualDNA02_thumb.png},
 pdf = {pdfs/Turkay2012DualDNA.pdf},
}

@article{Turkay12Representative,
 title = {Representative Factor Generation for the Interactive Visual Analysis of 
 High-Dimensional Data},
 author = {Cagatay Turkay and Arvid Lundervold and Astri Johansen Lundervold and 
 Helwig Hauser},
 event = {IEEE Information Visualization Conference 2012},
 location = {Seattle, WA, USA},
 journal={Visualization and Computer Graphics, IEEE Transactions on},
 year={2012},
 month={December},
 volume={18},
 number={12},
 pages={2621--2630},
 doi={10.1109/TVCG.2012.256},
 ISSN={1077-2626},
 abstract = {Datasets with a large number of dimensions per data item (hundreds or more) 
 are challenging both for computational and visual analysis. Moreover, these dimensions 
 have different characteristics and relations that result in sub-groups and/or hierarchies 
 over the set of dimensions. Such structures lead to heterogeneity within the dimensions. 
 Although the consideration of these structures is crucial for the analysis, most of the 
 available analysis methods discard the heterogeneous relations among the dimensions. 
 In this paper, we introduce the construction and utilization of representative factors 
 for the interactive visual analysis of structures in high-dimensional datasets. First, 
 we present a selection of methods to investigate the sub-groups in the dimension set and 
 associate representative factors with those groups of dimensions. Second, we introduce 
 how these factors are included in the interactive visual analysis cycle together with 
 the original dimensions. We then provide the steps of an analytical procedure that 
 iteratively analyzes the datasets through the use of representative factors. We discuss 
 how our methods improve the reliability and interpretability of the analysis process by 
 enabling more informed selections of computational tools. Finally, we demonstrate our 
 techniques on the analysis of brain imaging study results that are performed over a 
 large group of subjects.},
 pdf = {pdfs/Turkay12Representative.pdf},
 vid = {vids/Turkay12Representative.avi}, 
 images = {images/Turkay12Representative01.png, images/Turkay12Representative02.png},
 thumbnails = {images/Turkay12Representative01_thumb.png, images/Turkay12Representative02_thumb.png},
}

@misc{Helljesen12Contrast,
 author = {Linn Emilie S{\ae}vil Helljesen and Kim Nylund and Trygve Hausken and
  Georg Dimcevski and Odd Helge Gilja},
 title  ={Contrast-Enhanced Ultrasonography of liver lesions in patients referred 
  after inconclusive findings on {CT} - Preliminary Data},
 year = {2012},
 month = {April},
 howpublished = {Poster presented at the EUROSON Conference 2012},
 location = {Madrid, Spain},
 url = {http://www.euroson2012.com/},
 images = {images/Helljesen12Contrast01.png, images/Helljesen12Contrast02.png},
 thumbnails = {images/Helljesen12Contrast01_thumb.png, images/Helljesen12Contrast02_thumb.png},
 project = {illustrasound,medviz},
 pdf = {pdfs/Helljesen12Contrast.pdf}, 
}


@misc{Helljesen12CEUS,
 author = {Linn Emilie S{\ae}vil Helljesen},
 title  ={{CEUS} av leverlesjoner hos pasienter henvist etter uklare funn p{\aa} {CT}},
 year = {2012},
 month = {March},
 howpublished = {Talk at the NFUD-symposium / Frie foredrag},
 location = {Stavanger, Norway},
 url = {http://nfud.no/sites/default/files/Dokumenter/Programm_2012_Stavanger_kort.pdf},
 images = {images/no_thumb.png},
 thumbnails = {images/no_thumb.png},
 project = {illustrasound,medviz},
 pdf = {pdfs/Helljesen12CEUS.pdf}, 
}


@article{Helljesen12Klinisk,
 author = {Linn Emilie S{\ae}vil Helljesen and Spiros Kotopoulis and Kim Nylund and
  Ivan Viola and Trygve Hausken and Odd Helge Gilja},
 title = {Klinisk bruk av 3D-ultralyd},
 year = {2012},
 month = {June}, 
 journal = {Kirurgen},
 volume = {2},
 pages = {118--120},
 url = {http://www.kirurgen.no/fagstoff/teknologiutvikling/klinisk-bruk-av-3d-ultralyd},
 pdf = {pdfs/Helljesen12Klinisk.pdf},
 images = {images/Helljesen12Klinisk01.png, images/Helljesen12Klinisk02.png},
 thumbnails = {images/Helljesen12Klinisk01_thumb.png, images/Helljesen12Klinisk02_thumb.png},
 project = {illustrasound,medviz}
}


@inproceedings{Oye12Real,
 author = {Ola Kristoffer �ye and Wolfgang Wein and Dag Magne Ulvang and Knut Matre and
  Ivan Viola},
 title = {Real Time Image-based Tracking of 4D Ultrasound Data},
 year = {2012},
 month = {October},
 booktitle = {Lecture Notes in Computer Science (LNCS)},
 address = {Nice, France},
 url = {http://www.miccai2012.org/},
 event = {15th International Conference on Medical Image Computing and Computer
  Assisted Invervention (MICCAI)},
 abstract = {We propose a methodology to perform real time image-based
  tracking on streaming 4D ultrasound data, using image registration to
  deduce the positioning of each ultrasound frame in a global coordinate
  system. Our method provides an alternative approach to traditional external
  tracking devices used for tracking probe movements. We compare
  the performance of our method against magnetic tracking on phantom
  and liver data, and show that our method is able to provide results in
  agreement with magnetic tracking.},
 extra = {http://www.youtube.com/watch?v=iH6BhJruPRY},
 images = {images/Oye12Real01.png, images/Oye12Real02.png},
 thumbnails = {images/Oye12Real01_thumb.png, images/Oye12Real02_thumb.png},
 project = {illustrasound,medviz}
}


@inproceedings{Natali12Rapid,
 author = {Mattia Natali and Ivan Viola and Daniel Patel},
 title = {Rapid Visualization of Geological Concepts},
 year = {2012},
 month = {August},
 booktitle = {SIBGRAPI 2012 (XXV Conference on Graphics, Patterns and Images)},
 editor = {C. Freitas, L. Silva, R. Scopigno, and S. Sarkar},
 address = {Ouro Preto, MG, Brazil},
 url = {http://www.decom.ufop.br/sibgrapi2012/},
 abstract = {We describe a sketch-based system for constructing
  an illustrative visualization of the subsurface. An intuitive and
  rapid modelling tool is defined, which takes as input user�s
  strokes and creates a 3D layer-cake model of the earth. Our
  tool enables users to quickly express and communicate their
  ideas directly using a 3D model. For sketching, we have created
  geometric operators that capture the domain specific modelling
  requirements.We have devised sketching operators for expressing
  folding and faulting processes. This makes it possible to produce
  a large span of scenarios. Moreover, for communicating layer
  properties such as rock type and grain size, our system allows
  for associating user defined texture to each layer which can be
  deformed with a few sketch strokes.},
 images = {images/Natali12Rapid01.png, images/Natali12Rapid02.png},
 thumbnails = {images/Natali12Rapid01_thumb.png, images/Natali12Rapid02_thumb.png},
 project = {geoillustrator}
}


@article{Birkeland12TheUltrasound,
 author    = {{\AA}smund Birkeland and
               Veronika \v{S}olt{\'e}szov{\'a} and
               Dieter H{\"o}nigmann and
               Odd Helge Gilja and
               Svein Brekke and
               Timo Ropinski and
               Ivan Viola},
 title     = {The Ultrasound Visualization Pipeline - A Survey},
 journal   = {CoRR},
 volume    = {abs/1206.3975},
 year      = {2012},
 url       = {http://arxiv.org/abs/1206.3975},
  abstract = {Ultrasound is one of the most frequently used imaging modality in
  medicine. The high spatial resolution, its interactive nature and non-invasiveness
  makes it the first choice in many examinations. Image interpretation is one of ultrasound�s
  main challenges. Much training is required to obtain a confident skill level in
  ultrasound-based diagnostics. State-of-the-art graphics techniques is needed to provide
  meaningful visualizations of ultrasound in real-time. In this paper we present
  the process-pipeline for ultrasound visualization, including an overview of the tasks
  performed in the specific steps. To provide an insight into the trends of ultrasound
  visualization research, we have selected a set of significant publications and divided
  them into a technique-based taxonomy covering the topics pre-processing, segmentation,
  registration, rendering and augmented reality. For the different technique
  types we discuss the difference between ultrasound-based techniques and techniques
  for other modalities.},
 images = {images/Birkeland2012TheUltrasound.png}, 
 thumbnails = {images/Birkeland2012TheUltrasound_thumb.png},
 project = {illustrasound,medviz,illvis},
}


@inproceedings{Solteszova12Lowest,
 title = {Lowest-Variance Streamlines for Filtering of 3D Ultrasound},
 author = {Veronika \v{S}olt{\'e}szov{\'a} and Linn Emilie S{\ae}vil Helljesen and 
  Wolfgang Wein and Odd Helge Gilja and Ivan Viola},
 year = {2012},
 month = {Sep},
 booktitle = {Eurographics Workshop on Visual Computing for Biology and Medicine 
  (VCBM 2012)},
 pages = {41--48},
 location = {Norrk{\"o}ping, Sweden},
 abstract = {Ultrasound as an acoustic imaging modality suffers from various kinds of 
  noise. The presence of noise especially hinders the 3D visualization of ultrasound 
  data, both in terms of resolving the spatial occlusion of the signal by surrounding 
  noise, and mental decoupling of the signal from noise. This paper presents a novel 
  type of structurepreserving filter that has been specifically designed to eliminate 
  the presence of speckle and random noise in 3D ultrasound datasets. This filter is 
  based on a local distribution of variance for a given voxel. The lowest variance 
  direction is assumed to be aligned with the direction of the structure. A streamline 
  integration over the lowest-variance vector field defines the filtered output value. 
  The new filter is compared to other popular filtering approaches and its superiority 
  is documented on several use cases. A case study where a clinician was delineating
  vascular structures of the liver from 3D visualizations further demonstrates the 
  benefits of our approach compared to the state of the art.},
 url = {http://diglib.eg.org/EG/DL/WS/VCBM/VCBM12},
 DOI = {10.2312/VCBM/VCBM12/041-048},
 pdf = {pdfs/Solteszova12Lowest.pdf}, 
 images = {images/Solteszova12Lowest01.png, images/Solteszova12Lowest02.png},
 thumbnails = {images/Solteszova12Lowest01_thumb.png, images/Solteszova12Lowest02_thumb.png},
 project = {illustrasound,medviz,illvis},
}

@misc{Pobitzer12PacificVisTutorial,
 author = {Helwig Hauser and Alexander Kuhn and Armin Pobitzer and Maik Schulze},
 title  ={Time-Dependent Flow Visualization},
 year = {2012},
 month = {February},
 howpublished = {Tutorial at 5th IEEE PacificVis Symposium},
 location = {Songdo, South Korea},
 abstract = {Vector fields are a common representation of many kinds of dynamic 
  phenomena in a large variety of application fields.  A particularly 
  interesting class of vector fields represent time-dependent flows, 
  i.e., flows where the vectors change over time themselves.  A lot of 
  good and relevant research work has been done on the question of how 
  to visualize such unsteady vector fields and an overview is presented
  in this tutorial.  In particularly, we emphasize Lagrangian methods, 
  space-time domain approaches, and interactive visual analysis as 
  three interesting and promising types of methodology.  The tutorial 
  is also introduced with some general remarks, in particular also on 
  the question of why it often is not straight forward to extend methods
  that originally were developed for steady flows to the domain of 
  unsteady flows.  A number of examples illustrate the overview.},
 url ={http://www.semseg.eu/download/2012-02-28--TimeDepFlowVizTutorial--materials/},
 images = {images/Pobitzer12PacificVisTutorial.png},
 thumbnails = {images/Pobitzer12PacificVisTutorial_thumb.png},  
}

@misc{Pobitzer12Exploiting,
  author = {Armin Pobitzer},
  title  ={Exploiting the Turbulence Energy Cascade for Flow Visualization},
  year = {2012},
  month = {February},
  howpublished = {Invited talk at the weekly seminar of Laboratoire de M\'{e}canique de Lille},
  location = {Lille, France},
  abstract = {Even though modern technology and tools, together with available 
  computer power, theoretically enable us to visualise large vector fields
  directly, it often is neither interesting nor necessary to visualise 
  every detail of them. Usually, interesting features of the investigated 
  field can be visualized more efficiently using dedicated feature 
  detectors, e.g. the $\lambda_2$ criterion [2] for vertical structures.

  In settings with highly complex flow patterns, such as fully developed 
  turbulence, feature detectors may, however, mark almost the whole flow 
  domain as a feature. In these cases visualisations based on these 
  detectors become hard to interpret due to occlusion and visual 
  cluttering. This problem is well known in visualisation, and has been 
  addressed by previous work. Many of these methods have in common that 
  they extract all features at first, and discard some of them afterwards.
  Criteria for this discarding are often of geometrical character, such 
  as size (volume, length, area ...) or distance to next feature. While 
  the visual output of such strategies satisfies the need to reduce 
  occlusion and visual clutter, the interpretability of the results 
  remains an open question. The immediate relation between the velocity 
  field and the output of the feature detector is lost, since the 
  simplication is made on the `image-level' only.

  In this talk we discuss how the internal structure of flow fields can be
  exploited, in particular the turbulence energy cascade. Based on proper
  orthogonal decomposition [3], we present a general simplification 
  scheme for feature extraction that preserves the 1-to-1 relation between
  visual output of the method and the flow pattern it is extracted from. 
  We apply the simplification scheme on both Eulerian and Lagrangian 
  feature detectors and discuss the results. In particular the impact of 
  the simplification scheme on the detection and visualization of 
  Lagrangian Coherent Structures based on Finite-time Lyapunov exponents 
  is addressed. The results presented in this talk are published in the 
  article `Energy-scale Aware Feature Extraction for Flow Visualization  
  [4].

  [1] L. Hesselink, J. Helman, and P. Ning, Quantitative image processing 
  in fluid mechanics, Experimental Thermal and Fluid Science, 5 (1992), 
  pp. 605-616. Special Issue on Experimental Methods in Thermal and Fluid 
  Science.

  [2] J. Jeong and F. Hussain, On the identification of a vortex, Journal of 
  Fluid Mechanics, 285 (1995), pp. 69-84.

  [3] J. L. Lumley, The structure of inhomogeneous turbulent flows, in 
  Atmospheric Turbulence and Radio Wave Propagation, Elsevier, 1967, pp. 
  166-178.

  [4] A. Pobitzer, M. Tutkun, O Andreassen, R. Fuchs, R. Peikert, and H. 
  Hauser, Energy-scale aware feature extraction for flow visualization, 
  Computer Graphics Forum, 30 (2011), pp. 771-780.

  [5] F. Sadlo and R. Peikert, Visualizing Lagrangian coherent structures:
  A comparison to vector field topology, in Topology-Based Methods in 
  Visualization II: Proc. of the 2nd TopoInVis Workshop (TopoInVis 2007), 
  H.-C. Hege, K. Polthier, and G. Scheuermann, eds, 2009, pp. 15-29.},

 url = {http://lml.univ-lille1.fr/lml/?page=33&seminID=172},
 images = {images/no_thumb.png},
 thumbnails = {images/no_thumb.png},
}

@misc{Pobitzer12Physics,
 author = {Armin Pobitzer},
 title  ={Physics-based Velocity Field Simplification for Flow Visualization},
 year = {2012},
 month = {February},
 howpublished = {Invited talk at Minisymposium on Analysis and Representation of Large Data Sets},
 location = {Madrid, Spain},
 abstract = {With the availability of more computing power, simulations of increasingly complex 
  fluid flows have become possible. In the attempt to make sense of data, visualization has 
  greatly gained importance in everyday scientific computing. Many visualization techniques do, 
  however, suffer from a tendency to overly rich response in complex scenarios. Hence, filtering 
  of the visual output is an important topic. In this talk we discuss how such filtering can be 
  achieved in a physically meaningful way, giving examples from the extraction of vortices and 
  Lagrangian coherent structures.},
 pdf = {pdfs/Pobitzer12Physics.pdf},
 images = {images/Pobitzer12Physics.png},
 thumbnails = {images/Pobitzer12Physics_thumb.png},
}

@misc{Pobitzer12NceSubsea,
 author = {Armin Pobitzer},
 title  ={The State of the Art in Flow Visualization},
 year = {2012},
 month = {February},
 howpublished = {Invited talk at NCS Subsea Theme Meeting - Visualization for Industrial
  Applications},
 location = {Bergen, Norway},
 url = {http://eng.ncesubsea.no/page/389/activity/1029/theme-meeting-visualization-for-industrial-applications},
 pdf = {pdfs/Pobitzer12NceSubsea.pdf},
 images = {images/no_thumb.png},
 thumbnails = {images/no_thumb.png},
}

@article{Solteszova12APerceptual,
 title = {A Perceptual-Statistics Shading Model},
 author = {Veronika \v{S}olt{\'e}szov{\'a} and Cagatay Turkay and Mark Price and Ivan Viola},
 year = {2012},
 month = {Dec},
 journal = {Visualization and Computer Graphics, IEEE Transaction on},
 event = {IEEE Scientific Visualization Conference 2012},
 location = {Seattle, WA, USA},
 volume={18},
 number={12},
 pages={2265 -2274},
 doi={10.1109/TVCG.2012.188},
 ISSN={1077--2626}, 
 abstract = {The process of surface perception is complex and based on several influencing 
  factors, e.g., shading, silhouettes, occluding contours, and top down cognition. The 
  accuracy of surface perception can be measured and the influencing factors can be 
  modified in order to decrease the error in perception. This paper presents a novel 
  concept of how a perceptual evaluation of a visualization technique can contribute 
  to its redesign with the aim of improving the match between the distal and the proximal 
  stimulus. During analysis of data from previous perceptual studies, we observed that 
  the slant of 3D surfaces visualized on 2D screens is systematically underestimated. 
  The visible trends in the error allowed us to create a statistical model of the perceived 
  surface slant. Based on this statistical model we obtained from user experiments, we 
  derived a new shading model that uses adjusted surface normals and aims to reduce the 
  error in slant perception. The result is a shape-enhancement of visualization which is 
  driven by an experimentally-founded statistical model. To assess the efficiency of the 
  statistical shading model, we repeated the evaluation experiment and confirmed that the 
  error in perception was decreased. Results of both user experiments are publicly-available 
  datasets.},
 extra = {extra/Solteszova12APerceptual.zip}, 
 pdf = {pdfs/Solteszova12APerceptual.pdf},
 images = {images/Solteszova12APerceptual01.png, images/Solteszova12APerceptual02.png, images/Solteszova12APerceptual03.png},
 thumbnails = {images/Solteszova12APerceptual01_thumb.png, images/Solteszova12APerceptual02_thumb.png, images/Solteszova12APerceptual03_thumb.png},
 project = {illustrasound,medviz,illvis},
}

@article{Brambilla12AHierarchical,
 author = {Andrea Brambilla and Ivan Viola and Helwig Hauser},
 title = {A Hierarchical Splitting Scheme to Reveal Insight into Highly Self-Occluded
  Integral Surfaces},
 journal = {Journal of WSCG},
 volume = {20},
 number = {1},
 pages = {57--64},
 ISSN = {1213-6972},
 year = {2012},
 month = {July},
 publisher = {Union Agency},
 abstract = {In flow visualization, integral surfaces are of particular interest for 
  their ability to describe trajectories of massless particles. In areas of swirling 
  motion, integral surfaces can become very complex and difficult to understand. Taking 
  inspiration from traditional illustration techniques, such as cut-aways and exploded 
  views, we propose a surface analysis tool based on surface splitting and focus+context 
  visualization. Our surface splitting scheme is hierarchical and at every level of 
  the hierarchy the best cut is chosen according to a surface complexity metric. In
  order to make the interpretation of the resulting pieces straightforward, cuts are 
  always made along isocurves of specific flow attributes. Moreover, a degree of interest 
  can be specified, so that the splitting procedure attempts to unveil the occluded 
  interesting areas. Through practical examples, we show that our approach is able 
  to overcome the lack of understanding originating from structural occlusion.},
 URL = {http://wscg.zcu.cz/JWSCG/},
 event = {WSCG 2012 - 20th International Conference on Computer Graphics, Visualization
  and Computer Vision},
 location = {Pilsen, Czech Republic},
 pdf = {pdfs/Brambilla12AHierarchical.pdf},
 pres = {pdfs/Brambilla12AHierarchical.pptx},
 images = {images/Brambilla12AHierarchical01.png, images/Brambilla12AHierarchical02.png, images/Brambilla12AHierarchical03.png},
 thumbnails = {images/Brambilla12AHierarchical01_thumb.png, images/Brambilla12AHierarchical02_thumb.png, images/Brambilla12AHierarchical03_thumb.png},
 project = {semseg},
}

@article{Birkeland12Illustrative,
  title = {Illustrative Membrane Clipping},
  author = {{\AA}smund Birkeland and Stefan Bruckner and Andrea Brambilla and
    Ivan Viola},
  year = {2012},
  abstract = {Clipping is a fast, common technique for resolving occlusions. It only
   requires simple interaction, is easily understandable, and thus has been very
   popular for volume exploration. However, a drawback of clipping is that the technique
   indiscriminately cuts through features. Illustrators, for example, consider the
   structures in the vicinity of the cut when visualizing complex spatial data and
   make sure that smaller structures near the clipping plane are kept in the image
   and not cut into fragments. In this paper we present a new technique, which combines
   the simple clipping interaction with automated selective feature preservation using
   an elastic membrane. In order to prevent cutting objects near the clipping plane, 
   the deformable membrane uses underlying data properties to adjust itself to salient
   structures. To achieve this behaviour, we translate data attributes into a potential
   field which acts on the membrane, thus moving the problem of deformation into the
   soft-body dynamics domain. This allows us to exploit existing GPU-based physics 
   libraries which achieve interactive frame rates. For manual adjustment, the user 
   can insert additional potential fields, as well as pinning the membrane to interesting 
   areas. We demonstrate that our method can act as a flexible and non-invasive replacement 
   of traditional clipping planes.
  },
  pages = {905--914},
  month = {June},
  number = {3},
  note = {presented at EuroVis 2012},
  event = {EuroVis 2012},
  journal = {Computer Graphics Forum},
  volume = {31},
  location = {Vienna, Austria},
  keywords = {clipping, volume rendering, illustrative visualization},
  URL = {http://www.cg.tuwien.ac.at/research/publications/2012/Birkeland-2012-IMC/},
  pdf = {pdfs/Birkeland12Illustrative.pdf},
  vid = {vids/Birkeland12Illustrative.avi},
  images = {images/Birkeland12Illustrative01.png, images/Birkeland12Illustrative02.png, images/Birkeland12Illustrative03.png},
  thumbnails = {images/Birkeland12Illustrative01_thumb.png, images/Birkeland12Illustrative02_thumb.png, images/Birkeland12Illustrative03_thumb.png}, 
  project = {illustrasound,medviz,illvis}, 
}

@inproceedings{Pobitzer12Filtering,
 author = {Armin Pobitzer and Ronald Peikert and Raphael Fuchs and Holger Theisel
  and Helwig Hauser},
 title = {Filtering of FTLE for Visualizing Spatial Separation in Unsteady 3D Flow},
 booktitle = {Topological Methods in Data Analysis and Visualization II},
 editor = {R. Peikert and H. Hauser and H. Carr and R. Fuchs},
 publisher = {Springer},
 pages = {237--253},
 year = {2012},
  abstract = {Texture mapping is a common method for combining surface geometry with
  image data, with the resulting photorealistic 3D models being suitable not only
  for visualisation purposes but also for interpretation and spatial measurement, 
  in many application fields, such as cultural heritage and the earth sciences. When
  acquiring images for creation of photorealistic models, it is usual to collect more 
  data than is finally necessary for the texturing process. Images may be collected 
  from multiple locations, sometimes with different cameras or lens configurations 
  and large amounts of overlap may exist. Consequently, much redundancy may be present,
  requiring sorting to choose the most suitable images to texture the model triangles. 
  This paper presents a framework for visualization and analysis of the geometric 
  relations between triangles of the terrain model and covering image sets. The 
  application provides decision support for selection of an image subset optimized 
  for 3D model texturing purposes, for non-specialists. It aims to improve the communication 
  of geometrical dependencies between model triangles and the available digital images, 
  through the use of static and interactive information visualisation methods. The 
  tool was used for computer-aided selection of image subsets optimized for texturing 
  of 3D geological outcrop models. The resulting textured models were of high quality 
  and with a minimum of missing texture, and the time spent in time-consuming reprocessing 
  was reduced. Anecdotal evidence indicated that an increased user confidence in the 
  final textured model quality and completeness makes the framework highly beneficial.
 },
 doi = {http://dx.doi.org/10.1007/978-3-642-23175-9_16},
 url = {http://dx.doi.org/10.1007/978-3-642-23175-9_16},
 pdf = {pdfs/Pobitzer12Filtering.pdf},
 images = {images/Pobitzer12Filtering01.png, images/Pobitzer12Filtering02.png},
 thumbnails = {images/Pobitzer12Filtering01_thumb.png, images/Pobitzer12Filtering02_thumb.png}, 
 project = {semseg} 
}

@article{Sima12AnInteractive,
 author = {A. A. Sima and S. J. Buckley, I. Viola},
 title = {An interactive tool for analysis and optimization of texture parameters 
  in photorealistic virtual 3d models.},
 journal = {International Annals of Photogrammetry and Remote Sensing},
 year = {2012},
 abstract = {Texture mapping is a common method for combining surface geometry with
  image data, with the resulting photorealistic 3D models being suitable not only
  for visualisation purposes but also for interpretation and spatial measurement, 
  in many application fields, such as cultural heritage and the earth sciences. When
  acquiring images for creation of photorealistic models, it is usual to collect more 
  data than is finally necessary for the texturing process. Images may be collected 
  from multiple locations, sometimes with different cameras or lens configurations 
  and large amounts of overlap may exist. Consequently, much redundancy may be present,
  requiring sorting to choose the most suitable images to texture the model triangles. 
  This paper presents a framework for visualization and analysis of the geometric 
  relations between triangles of the terrain model and covering image sets. The 
  application provides decision support for selection of an image subset optimized 
  for 3D model texturing purposes, for non-specialists. It aims to improve the communication 
  of geometrical dependencies between model triangles and the available digital images, 
  through the use of static and interactive information visualisation methods. The 
  tool was used for computer-aided selection of image subsets optimized for texturing 
  of 3D geological outcrop models. The resulting textured models were of high quality 
  and with a minimum of missing texture, and the time spent in time-consuming reprocessing 
  was reduced. Anecdotal evidence indicated that an increased user confidence in the 
  final textured model quality and completeness makes the framework highly beneficial.
 },
 images = {images/Sima12AnInteractive01.png, images/Sima12AnInteractive02.png},
 thumbnails = {images/Sima12AnInteractive01_thumb.png, images/Sima12AnInteractive02_thumb.png}, 
}


@inproceedings{Lidal12Geological,
 author = {Endre M. Lidal and Helwig Hauser and Ivan Viola },
 title = {Geological Storytelling - Graphically Exploring and Communicating Geological 
  Sketches},
 booktitle = {Proceedings of Sketch-Based Interfaces and Modeling (SBIM 2012)},
 year = {2012},
 pages = {11--20},
 URL = {http://diglib.eg.org/EG/DL/WS/SBM/SBM12/011-020.pdf},
 DOI = {10.2312/SBM/SBM12/011-020},
 abstract = {Developing structural geological models from exploratory subsea imaging 
  is difficult and an ill-posed process. Therefore, in practice several experts 
  generate a larger number of geological interpretations. This leads to the situation
  that a number of geological sketches are prepared and examined for the next steps 
  in the oil and gas exploration pipeline. In this paper, we present Geological 
  Storytelling, a novel graphical approach for performing rapid and expressive 
  geomodeling of a multitude of model variations. The solution builds on a flip-over 
  metaphor for sketching the individual steps in a story that externalizes the
  mental steps the modeler performs when developing the model. The stories, through 
  the discrete story steps, are then visualized in a Story Tree for easy access 
  and management. This tree also provides the interface for individual story playback 
  and examination, or comparative visualization of several stories. With our approach, 
  the experts can rapidly sketch geological stories that both visualize the proposed 
  model of today's geology and visualize how the expert derived this model. Presenting 
  the model as a visual story helps the peers to evaluate the geological soundness 
  of the model. We have developed geological storytelling in collaboration with 
  domain experts that work with such challenges on a daily basis. Our focus of this 
  work has been on models derived from single seismic slices. We have implemented 
  a prototype of Geological Storytelling to demonstrate our concept and to get domain 
  expert feedback.},
 pdf = {pdfs/Lidal12Geological.pdf},
 images = {images/Lidal12Geological01.png, images/Lidal12Geological02.png},
 thumbnails = {images/Lidal12Geological01_thumb.png, images/Lidal12Geological02_thumb.png}, 
 project = {geoillustrator}
}


@inproceedings{Brambilla12Illustrative,
 author = {Andrea Brambilla and Robert Carnecky and Ronald Peikert and Ivan Viola and
  Helwig Hauser},
 title = {Illustrative Flow Visualization: State of the Art, Trends and Challenges},
 booktitle = {EuroGraphics 2012 State of the Art Reports (STARs)},
 year = {2012},
 pages = {75--94},
 abstract = {Flow visualization is a well established branch of scientific 
  visualization and it currently represents an invaluable resource to many 
  fields, like automotive design, meteorology and medical imaging. Thanks to the
  capabilities of modern hardware, flow datasets are increasing in size and 
  complexity, and traditional flow visualization techniques need to be updated 
  and improved in order to deal with the upcoming challenges. A fairly recent 
  trend to enhance the expressiveness of scientific visualization is to produce 
  depictions of physical phenomena taking inspiration from traditional 
  handcrafted illustrations: this approach is known as illustrative 
  visualization, and it is getting a foothold in flow visualization as well.
  In this state of the art report we give an overview of the existing 
  illustrative techniques for flow visualization, we highlight which problems 
  have been solved and which issues still need further investigation, and, 
  finally, we provide remarks and insights on the current trends in illustrative 
  flow visualization.},
 URL = {http://diglib.eg.org/EG/DL/conf/EG2012/stars/075-094.pdf},
 DOI = {10.2312/conf/EG2012/stars/075-094},
 location = {Cagliari, Italy},
 pdf = {pdfs/Brambilla12Illustrative.pdf},
 pres = {pdfs/Brambilla12Illustrative.pptx},
 images = {images/Brambilla12Illustrative.png},
 thumbnails = {images/Brambilla12Illustrative_thumb.png},
 project = {semseg},
}


@inproceedings{Lidal12Design,
 title = {Design Principles for Cutaway Visualization of Geological Models},
 author = {Endre M. Lidal and Helwig Hauser and Ivan Viola},
 year = {2012},
 month = {May},
 booktitle = {Proceedings of Spring Conference on Computer Graphics (SCCG 2012)},
 pages = {53--60},
 location = {Smolenice castle, Slovakia},
 pdf = {pdfs/Lidal12Design.pdf},
 images = {images/Lidal12Design01.jpg, images/Lidal12Design02.jpg},
 thumbnails = {images/Lidal12Design01_thumb.jpg, images/Lidal12Design02_thumb.jpg},
 project = {geoillustrator},
 abstract = {In this paper, we present design principles for cutaway visualizations
  that emphasize shape and depth communication of the focus
  features and their relation to the context. First, to eliminate
  cutaway-flatness we argue that the cutaway axis should have an angular
  offset from the view direction. Second, we recommend creating
  a box-shaped cutaway. Such a simple cutaway shape allows for
  easier context extrapolation in the cutaway volume. Third, to improve
  the relationship between the focus features and the context,
  we propose to selectively align the cutaway shape to familiar structures
  in the context. Fourth, we emphasize that the illumination
  model should effectively communicate the shape and spatial ordering
  inside the cutaway, through shadowing as well as contouring
  and other stylized shading models. Finally, we recommend relaxing
  the view-dependency constraint of the cutaway to improve the
  depth perception through the motion parallax. We have identified
  these design principles while developing interactive cutaway visualizations
  of 3D geological models, inspired by geological illustrations
  and discussions with the domain illustrators and experts.},
}


@inproceedings{Solteszova12Stylized,
 title = {Stylized Volume Visualization of Streamed Sonar Data},
 author = {Veronika \v{S}olt{\'e}szov{\'a} and Ruben Patel and Helwig Hauser and Ivanko Viola},
 year = {2012},
 month = {May},
 booktitle = {Proceedings of Spring Conference on Computer Graphics (SCCG 2012)},
 pages = {13--20},
 location = {Smolenice castle, Slovakia},
 vid = {vids/Solteszova12Stylized.avi},
 pdf = {pdfs/Solteszova12Stylized.pdf},
 images = {images/Solteszova12Stylized01.png, images/Solteszova12Stylized02.png, images/Solteszova12Stylized03.png},
 thumbnails = {images/Solteszova12Stylized01_thumb.png, images/Solteszova12Stylized02_thumb.png, images/Solteszova12Stylized03_thumb.png},
 project = {illustrasound,medviz,illvis},
 abstract = {Current visualization technology implemented in the software for
  2D sonars used in marine research is limited to slicing whilst volume
  visualization is only possible as post processing. We designed
  and implemented a system which allows for instantaneous volume
  visualization of streamed scans from 2D sonars without prior resampling
  to a voxel grid. The volume is formed by a set of most recent
  scans which are being stored. We transform each scan using its
  associated transformations to the view-space and slice their bounding
  box by view-aligned planes. Each slicing plane is reconstructed
  from the underlying scans and directly used for slice-based volume
  rendering. We integrated a low frequency illumination model 
  which enhances the depth perception of noisy acoustic measurements.
  While we visualize the 2D data and time as 3D volumes, the
  temporal dimension is not intuitively communicated. Therefore, we
  introduce a concept of temporal outlines. Our system is a result of
  an interdisciplinary collaboration between visualization and marine
  scientists. The application of our system was evaluated by independent
  domain experts who were not involved in the design process
  in order to determine real life applicability.},
 note = {Second best paper and second best presentation awards},
}


@inproceedings{Pobitzer12AStatistics,
 title = {A Statistics-based Dimension Reduction of the Space of Path Line Attributes
  for Interactive Visual Flow Analysis},
 author = {Armin Pobitzer and Alan Lez and Kresimir Matkovic and Helwig Hauser},
 year = {2012},
 booktitle = {Proceedings of the IEEE Pacific Visualization Symposium 
  (PacificVis 2012)},
 pages = {113--120},
 month = {March},
 location = {Songdo, Korea},
 pdf = {pdfs/Pobitzer12AStatistics.pdf},
 images = {images/Pobitzer12AStatistics.png},
 thumbnails = {images/Pobitzer12AStatistics_thumb.png},
 abstract = {Recent work has shown the great potential of interactive flow analysis
  by the analysis of path lines. The choice of suitable attributes,
  describing the path lines, is, however, still an open question. This
  paper addresses this question performing a statistical analysis of the
  path line attribute space. In this way we are able to balance the usage
  of computing power and storage with the necessity to not loose
  relevant information. We demonstrate how a carefully chosen attribute
  set can improve the benefits of state-of-the art interactive flow
  analysis. The results obtained are compared to previously published
  work.},
}

@ARTICLE{Ma12ScientificStorytelling, 
 author={Kwan-Liu Ma and I. Liao and J. Frazier and H. Hauser and 
  H.-N. Kostis}, 
 journal={Computer Graphics and Applications, IEEE}, 
 title={Scientific Storytelling Using Visualization}, 
 year={2012}, 
 month={Jan.--Feb.}, 
 volume={32}, 
 number={1}, 
 pages={12 -19}, 
 abstract={Scientists frequently tell stories using visualizations of scientific 
  data, in the process of disseminating findings to peers and the general 
  public. However, techniques and methods for effective scientific storytelling 
  have received little attention so far. This article explores how literary and 
  theatrical narrative conventions can inform the design and presentation of 
  visualizations, and discusses the challenges of adapting scientific 
  visualizations for broader audiences. It also summarizes recent workshops' 
  findings on the role of storytelling in visualizations, and presents several 
  examples of successful scientific-storytelling production teams. The 
  conclusion is that scientific storytelling deserves greater support and 
  recognition by the visualization community.}, 
 keywords={literary narrative convention;scientific data visualization;
  scientific storytelling;theatrical narrative convention;data visualisation;
  natural sciences computing;}, 
 doi={10.1109/MCG.2012.24},
 url={http://dx.doi.org/10.1109/MCG.2012.24},
 ISSN={0272-1716},
 pdf={pdfs/Ma12ScientificStorytelling.pdf},
 images={images/Ma12ScientificStorytelling01.jpg, images/Ma12ScientificStorytelling02.jpg , images/Ma12ScientificStorytelling03.jpg, ../../../_images/CGA--2012-01--Cover.png},
 thumbnails={images/Ma12ScientificStorytelling01_thumb.jpg, images/Ma12ScientificStorytelling02_thumb.jpg , images/Ma12ScientificStorytelling03_thumb.jpg, ../../../_images/CGA--2012-01--Cover_thumb.png},
}

@inproceedings{Parulek12ImplicitRepresentation,
 title = {Implicit Representation of Molecular Surfaces},
 author = {Julius Parulek and Ivan Viola},
 year = {2012},
 booktitle = {Proceedings of the IEEE Pacific Visualization Symposium 
  (PacificVis 2012)},
 pages = {217--224},
 month = {March},
 location = {Songdo, Korea},
 pdf = {pdfs/Parulek12ImplicitRepresentation.pdf},
 images = {images/Parulek12ImplicitRepresentation.png},
 thumbnails = {images/Parulek12ImplicitRepresentation_thumb.png},
 abstract = {Molecular surfaces are an established tool to analyze and to study
  the evolution and interaction of molecules. One of the most advanced
  representations of molecular surfaces is called the solvent excluded surface.
  We present a novel and a simple method for representing the solvent excluded
  surfaces (SES). Our method requires no precomputation and therefore allows us
  to vary SES parameters outright. We utilize the theory of implicit surfaces
  and their CSG operations to compose the implicit function representing the
  molecular surface locally. This function returns a minimal distance to the
  SES representation. Additionally, negative values of the implicit function
  determine that the point lies outside SES whereas positive ones that the point
  lies inside. We describe how to build this implicit function composed of three
  types of patches constituting the SES representation. Finally, we propose a
  method to visualize the iso-surface of the implicit function by means of
  ray-casting and the set of rendering parameters affecting the overall
  performance.},
  project = {physioillustration}
}

@misc{Viola12Physiological,
 author = {Ivan Viola},
 title = {Illustrative Visualization of Physiological Models and Imaging},
 year = {2012},
 month = {January},
 howpublished = {Talk in the MedViz Conference 2012},
 location = {Bergen, Norway},
 abstract = {Physiological processes are of multi-scale and multi-system 
  nature. In general they are very difficult to comprehend. This talk 
  discusses challenges of an upcoming research project that aims at 
  proposing an entirely novel research agenda within the data 
  visualization research field to enable understanding, communication, 
  and evaluation of physiology through interactive and 
  easy-to-understand visualization. The visualization metaphors 
  investigated are inspired by textbook illustrations and handcrafted 
  animated illustrations. The primary focus is on development of novel 
  graphics data representations, visual representations, occlusion 
  handling, visual guidance and storytelling, zooming, interaction and 
  integration of physiological models and medical imaging. 
  The visualization technology will be developed and evaluated on 
  multiple scale levels, from molecular machines, up to the organ level.
  The physiological context for the technological development and 
  evaluation will be primarily the muscular system. The outcome of the 
  discussed project is new visualization technology in form of algorithms, 
  concepts, and proof of concept implementations. The utilization of 
  the outcome can lead to advances in the field of physiology by 
  providing intuitive visual representation, which the user can observe 
  and interact with.},
 images = {images/no_thumb.png},
 thumbnails = {images/no_thumb.png},
 project = {physioillustration, medviz}
}