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Schinko, Christoph; Peer, Markus; Hammer, Daniel; Pirstinger, Matthias; Lex, Cornelia; Koglbauer, Ioana; Eichberger, Arno; Holzinger, Jürgen; Eggeling, Eva; Fellner, Dieter W.; Ullrich, Torsten

Building a Driving Simulator with Parallax Barrier Displays

2016

Magnenat-Thalmann, Nadia (Ed.) et al.: Proceedings of the 11th Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications. Volume 1 : 11th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications. SciTePress, 2016, pp. 283-291

International Joint Conference on Computer Vision and Computer Graphics Theory and Applications (VISIGRAPP) <11, 2016, Rome, Italy>

In this paper, we present an optimized 3D stereoscopic display based on parallax barriers for a driving simulator. The overall purpose of the simulator is to enable user studies in a reproducible environment under controlled conditions to test and evaluate advanced driver assistance systems. Our contribution and the focus of this article is a visualization based on parallax barriers with (I) a-priori optimized barrier patterns and (II) an iterative calibration algorithm to further reduce visualization errors introduced by production inaccuracies. The result is an optimized 3D stereoscopic display perfectly integrated into its environment such that a single user in the simulator environment sees a stereoscopic image without having to wear specialized eye-wear.

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Ladenhauf, Daniel; Battisti, Kurt; Berndt, Rene; Eggeling, Eva; Fellner, Dieter W.; Gratzl-Michlmair, Markus; Ullrich, Torsten

Computational Geometry in the Context of Building Information Modeling

2016

Energy and Buildings, Vol.115 (2016), pp. 78-84

Building energy analysis has gained attention in recent years, as awareness for energy efficiency is rising in order to reduce greenhouse gas emissions. At the same time, the building information modeling paradigm is aiming to develop comprehensive digital representations of building characteristics based on semantic 3D models. Most of the data required for energy performance calculation can be found in such models; however, extracting the relevant data is not a trivial problem. This article presents an algorithm to prepare input data for energy analysis based on building information models. The crucial aspect is geometric simplification according to semantic constraints: the building element geometries are reduced to a set of surfaces representing the thermal shell as well as the internal boundaries. These boundary parts are then associated with material layers and thermally relevant data. The presented approach, previously discussed at the International Academic Conference on Places and Technologies (Ladenhauf et al., 2014), significantly reduces the needed time for energy analysis.

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Silva, Nelson; Shao, Lin; Schreck, Tobias; Eggeling, Eva; Fellner, Dieter W.

Sense.me - Open Source Framework for the Exploration and Visualization of Eye Tracking Data

2016

IEEE Computer Society, 2016

IEEE Conference on Visualization (VIS) <2016, Baltimore, USA>

We present a new open-source prototype framework to explore and visualize eye-tracking experiments data. Firstly, standard eyetrackers are used to record raw eye gaze data-points on user experiments. Secondly, the analyst can configure gaze analysis parameters, such as, the definition of areas of interest, multiple thresholds or the labeling of special areas, and we upload the data to a search server. Thirdly, a faceted web interface for exploring and visualizing the users' eye gaze on a large number of areas of interest is available. Our framework integrates several common visualizations and it also includes new combined representations like an eye analysis overview and a clustered matrix that shows the attention time strength between multiple areas of interest. The framework can be readily used for the exploration of eye tracking experiments data. We make available the source code of our prototype framework for eye-tracking data analysis.

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Berndt, Rene; Silva, Nelson; Caldera, Christian; Krispel, Ulrich; Eggeling, Eva; Sunk, Alexander; Reisinger, Gerhard; Sihn, Wilfried; Fellner, Dieter W.

VASCO - Digging the Dead Man's Chest of Value Streams

2016

International Journal on Advances in Intelligent Systems, Vol.9 (2016), 3, pp. 401-416

Value stream mapping is a lean management method for analyzing and optimizing a series of events for production or services. Even today the first step in value stream analysis - the acquisition of the current state map - is still created using pen & paper by physically visiting the production line. We capture a digital representation of how manufacturing processes look like in reality. The manufacturing processes can be represented and efficiently analyzed for future production planning as a future state map by using a meta description together with a dependency graph. With VASCO we present a tool, which contributes to all parts of value stream analysis - from data acquisition, over analyzing, planning, comparison up to simulation of alternative future state maps. We call this a holistic approach for Value stream mapping including detailed analysis of lead time, productivity, space, distance, material disposal, energy and carbon dioxide equivalents - depending in a change of calculated direct product costs.

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Berndt, Rene; Silva, Nelson; Caldera, Christian; Krispel, Ulrich; Eggeling, Eva; Sunk, Alexander; Edtmayr, Thomas; Sihn, Wilfried; Fellner, Dieter W.

VASCO - Mastering the Shoals of Value Stream Mapping

2016

Sehring, Hans-Werner (Ed.) et al.: CONTENT 2016 : The Eighth International Conference on Creative Content Technologies [online]. [cited 22 June 2017] Available from: http://www.thinkmind.org/index.php?view=instance&instance=CONTENT+2016: ThinkMind, 2016, pp. 42-47

International Conference on Creative Content Technologies (CONTENT) <8, 2016, Rome, Italy>

Value stream mapping is a lean management method for analyzing and optimizing a series of events for production or services. Even today the first step in value stream analysis - the acquisition of the current state - is still created using pen & paper by physically visiting the production place. We capture a digital representation of how manufacturing processes look like in reality. The manufacturing processes can be represented and efficiently analyzed for future production planning by using a meta description together with a dependency graph. With our Value Stream Creator and explOrer (VASCO) we present a tool, which contributes to all parts of value stream analysis - from data acquisition, over planning, comparison with previous realities, up to simulation of future possible states.

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Silva, Nelson; Shao, Lin; Schreck, Tobias; Eggeling, Eva; Fellner, Dieter W.

Visual Exploration of Hierarchical Data Using Degree-of-Interest Controlled by Eye-Tracking

2016

Aigner, Wolfgang (Ed.) et al.: FMT 2016 : Proceedings of the 9th Forum Media Technology 2016 and 2nd All Around Audio Symposium 2016. (CEUR Workshop Proceedings 1734), pp. 82-89

Forum Media Technology (FMT) <9, 2016, St. Pölten, Austria>

Effective visual exploration of large data sets is an important problem. A standard technique for mapping large data sets is to use hierarchical data representations (trees, or dendrograms) that users may navigate. If the data sets get large, so do the hierarchies, and effective methods for the navigation are required. Traditionally, users navigate visual representations using desktop interaction modalities, including mouse interaction. Motivated by recent availability of lowcost eye-tracker systems, we investigate application possibilities to use eye-tracking for controlling the visual-interactive data exploration process. We implemented a proof-of-concept system for visual exploration of hierarchic data, exemplified by scatter plot diagrams which are to be explored for grouping and similarity relationships. The exploration includes usage of degree-of-interest based distortion controlled by user attention read from eye-movement behavior. We present the basic elements of our system, and give an illustrative use case discussion, outlining the application possibilities. We also identify interesting future developments based on the given data views and captured eye-tracking information.

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Barmak, Katayun; Eggeling, Eva; Emelianenko, Maria; Epshteyn, Yekaterina; Kinderlehrer, David; Sharp, Richard; Ta'asan, Shlomo

Recent Developments in Material Microstructure: a Theory of Coarsening

2015

Calderer, C. (Ed.) et al.: Symposium NN - Mathematical and Computational Aspects of Materials Science. Cambridge: Cambridge University Press (CUP), 2015. (MRS Online Proceedings Library 1753), 11 p.

Symposium NN: Mathematical and Computational Aspects of Materials Science <2014, Boston, MA, USA>

Cellular networks are ubiquitous in nature. Most engineered materials are polycrystalline mi- crostructures composed of a myriad of small grains separated by grain boundaries, thus comprising cellular networks. The recently discovered grain boundary character distribution (GBCD) is an empirical distribution of the relative length (in 2D) or area (in 3D) of interface with a given lattice misorientation and normal. During the coarsening, or growth, process, an initially random grain boundary arrangement reaches a steady state that is strongly correlated to the interfacial energy density. In simulation, if the given energy density depends only on lattice misorientation, then the steady state GBCD and the energy are related by a Boltzmann distribution. This is among the simplest non-random distributions, corresponding to independent trials with respect to the energy. Why does such simplicity emerge from such complexity? Here we describe an entropy based theory which suggests that the evolution of the GBCD satisfies a Fokker-Planck Equation, an equation whose stationary state is a Boltzmann distribution.

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Eggeling, Eva; Settgast, Volker; Silva, Nelson; Poiger, Michael; Zeh, Theodor; Fellner, Dieter W.

The Sixth Sense of an Air Traffic Controller

2015

Schaefer, Dirk (Ed.): Proceedings of the SESAR Innovation Days [online]. [cited 31. March 2016] http://www.sesarinnovationdays.eu/2015/papersandpresentations: EUROCONTROL, 2015, 8 p.

SESAR Innovation Days <5, 2015, Bologna, Italy>

The project Sixth Sense postulates that the users body language is different at "good" and "bad" decisions. Therefore, in Sixth Sense we are looking for patterns or hidden data signs that allow us to detect moments of bad and good decisions that could be incorporated in an automated system in order to detect and eventually predict the next actions of a user. In our case the user is an Air Traffic Controller (ATCO). Specifically, we intend to analyse the correlation between the change in the ATCO's behaviour - expressed through his body language - and the quality of his/her decision. For that, an experiment was set up to collect, explore and analyse data about the user behaviour. The results of our work may be used for early warnings for upcoming "bad" situations or decision aids for ATCOs.

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Caldera, Christian; Berndt, Rene; Eggeling, Eva; Schröttner, Martin; Fellner, Dieter W.

"Mining Bibliographic Data" - Using Author's Publication History for a Brighter Reviewing Future within Conference Management Systems

2014

International Journal on Advances in Intelligent Systems, Vol.7 (2014), 3 & 4, pp. 609-619

Organizing and managing a conference is a cumbersome and time consuming task. Electronic conference management systems support reviewers, conference chairs and the International Programme Committee members (IPC) in managing the huge amount of submissions. These systems implement the complete workflow of scientific conferences. One of the most time consuming tasks within a conference is the assignment of IPC members to the submissions. Finding the best-suited person for reviewing a paper strongly depends on the expertise of the IPC member. There are already various approaches like "bidding" or "topic matching". However, these approaches allocate a considerable amount of resources on the IPC member side. This article introduces how the workflow of a conference looks like and what the challenges for an electronic conference management are. It will take a close look on the latest version of the Eurographics Submission and Review Management system (SRMv2). Finally, it will introduce an extension of SRMv2 called the Paper Rating and IPC Matching Tool (PRIMA), which reduces the workload for both - IPC members and chairs - to support and improve the assignment process.

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Schinko, Christoph; Berndt, Rene; Eggeling, Eva; Fellner, Dieter W.

A Scalable Rendering Framework for Generative 3D Content

2014

Polys, Nicholas F. (General Chair) et al.: Proceedings Web3D 2014 : 19th International Conference on 3D Web Technology. New York: ACM, 2014, pp. 81-87

International Conference on 3D Web Technology (WEB3D) <19, 2014, Vancouver, BC, Canada>

Delivering high quality 3D content through a web browser is still a challenge especially when intellectual property (IP) protection is necessary. Thus, the transfer of 3D modeling information to a client should be avoided. In our work we present a solution to this problem by introducing a server-side rendering framework. Only images are transferred to the client, the actual 3D content is not delivered. By providing simple proxy geometry it is still possible to provide direct interaction on the client. Our framework incorporates the Generative Modeling Language (GML) for the description and rendering of generative content. It is then possible to not only interact with the 3D content, but to modify the actual shape within the possibilities of the generative content. By introducing a control layer and encapsulating processing and rendering of the generative content in a so called GML Rendering Unit (GRU) it is possible to provide a scalable rendering framework.

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Ladenhauf, Daniel; Berndt, Rene; Eggeling, Eva; Ullrich, Torsten; Battisti, Kurt; Gratzl-Michlmair, Markus

From Building Information Models to Simplified Geometries for Energy Performance Simulation

2014

Lazarevic, Eva Vanista (Ed.) et al.: Proceedings of International Academic Conference on Places and Technologies : Keeping up with Technologies to Improve Places [online]. [cited 16 December 2014] Available from: http://placesandtechnologies.eu/about.html: University of Belgrade, 2014, pp. 669-676

International Academic Conference on Places and Technologies <1, 2014, Belgrade, Serbia>

A major future challenge in the building industry is to reduce primary energy use of buildings. EU law now requires energy performance certificates to be issued for all buildings. Hence, energy performance simulation becomes an increasingly important topic. Accurate, yet efficient simulation depends on simple building models. Most of the required data can be found in Building Information Models (BIM), following the buildingSMART alliance's Industry Foundation Classes (IFC) schema. IFC has become an ISO standard and enjoys increasing support by CAD software. However, typical IFC models contain a lot of irrelevant data, in particular geometric representations, which are too detailed for energy performance simulation. Therefore, an algorithm is proposed for extracting input models for simulations directly from IFC models in a semi-automatic process, to overcome the current situation where simple models are manually built from scratch. The key aspect of the algorithm is geometry simplification subject to semantic and functional groups; more specifically, the 3D representations of walls, slabs, windows, doors, etc. are reduced to a collection of surfaces describing the building's thermal shell on one hand, and the material layers associated with it on the other hand. Test models from simple fictitious houses to complex models of real-world buildings have been provided to guide the development of the algorithm in an incremental manner. This paper presents the resulting algorithm and the current status of prototype software implementing it.

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Ladenhauf, Daniel; Berndt, Rene; Krispel, Ulrich; Eggeling, Eva; Ullrich, Torsten; Battisti, Kurt; Gratzl-Michlmair, Markus

Geometry Simplification According to Semantic Constraints: Enabling Energy Analysis Based on Building Information Models

2014

Computer Science - Research and Development, (2014), Online first: November 2014

The building industry and facility management is in a state of upheaval: The complexity of the realworld is now represented in its digital counterpart. The established object-based file format "Industrial Foundation Classes (IFC)" developed by the International Alliance for Interoperability facilitates interoperability in the context of Building Information Modeling. Unfortunately, there is no feasible workflow for filtering energy-related information, e.g. a streamlined version of the building geometry. Simplification methods often fail on CAD data that is ignorant of domain specific semantic information (i.e. functional differences between a door and stucco are not reflected in the geometry and are therefore often ignored). With EU law now requiring energy performance certificates to be issued for all buildings, energy performance analysis becomes an increasingly important topic. Accurate, yet efficient calculation depends on simple building models. However, typical IFC models contain a lot of irrelevant data, in particular geometric representations, which are too detailed for energy performance analysis. Therefore, we propose an algorithm that extracts input models suitable for calculations directly from IFC models in a semi-automatic process. The key aspect of the algorithm is geometry simplification subject to semantic and functional groups; more specifically, the 3D representations of walls, slabs, windows, doors, etc. are reduced to a collection of surfaces describing the building's thermal shell on one hand, and the material layers associated with it on the other hand. This simplification takes into account semantic constraints and expert knowledge. Furthermore, it works on "real-world" data; i.e. it is robust towards incomplete, imperfect and inconsistent data.

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Caldera, Christian; Berndt, Rene; Eggeling, Eva; Schröttner, Martin; Fellner, Dieter W.

PRIMA - Towards an Automatic Review/Paper Matching Score Calculation

2014

Sehring, Hans-Werner (Ed.) et al.: CONTENT 2014 : The Sixth International Conference on Creative Content Technologies [online]. [cited 18 June 2015] Available from: http://www.thinkmind.org/index.php?view=instance&instance=CONTENT+2014: ThinkMind, 2014, pp. 71-75

International Conference on Creative Content Technologies (CONTENT) <6, 2014, Venice, Italy>

Programme chairs of scientific conferences face a tremendous time pressure. One of the most time-consuming steps during the conference workflow is assigning members of the international programme committee (IPC) to the received submissions. Finding the best-suited persons for reviewing strongly depends on how the paper matches the expertise of each IPC member. While various approaches like "bidding" or "topic matching" exist in order to make the knowledge of these expertises explicit, these approaches allocate a considerable amount of resources on the IPC member side. This paper introduces the Paper Rating and IPC Matching Tool (PRIMA), which reduces the workload for both - IPC members and chairs - to support and improve the assignment process.

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Silva, Nelson; Settgast, Volker; Eggeling, Eva; Grill, Florian; Zeh, Theodor; Fellner, Dieter W.

Sixth Sense - Air Traffic Control Prediction Scenario Augmented by Sensors

2014

Lindstaedt, Stefanie (Ed.) et al.: i-KNOW 2014 : Proceedings of the 14th International Conference on Knowledge Technologies and Data-driven Business. New York: ACM, 2014. (ACM International Conference Proceedings Series 889), Article 34, 4 p.

International Conference on Knowledge Technologies and Data-driven Business (I-KNOW) <14, 2014, Graz, Austria>

This paper is focused on the fault tolerance of Human Machine Interfaces in the field of air traffic control (ATC) by accepting the overall user's body language as input. We describe ongoing work in progress in the project called Sixth Sense. Interaction patterns are reasoned from the combination of a recommendation and inference engine, the analysis of several graph database relationships and from multiple sensor raw data aggregations. Altogether, these techniques allow us to judge about different possible meanings of the current user's interaction and cognitive state. The results obtained from applying different machine learning techniques will be used to make recommendations and predictions on the user's actions. They are currently monitored and rated by a human supervisor.

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Sturm, Werner; Berndt, Rene; Halm, Andreas; Ullrich, Torsten; Eggeling, Eva; Fellner, Dieter W.

Time-based Visualization of Large Data-Sets. An Example in the Context of Automotive Engineering

2014

International Journal on Advances in Software, Vol.7 (2014), 1-2, pp. 139-149

Automotive systems can be very complex when using multiple forms of energy. To achieve better energy efficiency, engineers require specialized tools to cope with that complexity and to comprehend how energy is spread and consumed. This is especially essential to develop hybrid systems, which generate electricity by various available forms of energy. Therefore, highly specialized visualizations of multiple measured energies are needed. This paper examines several three-dimensional glyphbased visualization techniques for spatial multivariate data. Besides animated glyphs, two-dimensional visualization techniques for temporal data to allow detailed trend analysis are considered as well. Investigations revealed that Scaled Data-Driven Spheres are best suited for a detailed 3D exploration of measured data. To gain a better overview of the spatial data, Cumulative Glyphs are introduced. For trend analysis, Theme River and Stacked Area Graphs are used. All these visualization techniques are implemented as a web-based prototype without the need of additional web browser plugins using X3DOM and Data-Driven Documents.

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Sturm, Werner; Berndt, Rene; Halm, Andreas; Ullrich, Torsten; Eggeling, Eva; Fellner, Dieter W.

Energy Balance: A Web-based Visualization of Energy for Automotive Engineering Using X3DOM

2013

Sehring, Hans-Werner: CONTENT 2013 : The Fifth International Conference on Creative Content Technologies [online]. [cited 07 April 2014] Available from: http://www.thinkmind.org/index.php?view=instance&instance=CONTENT+2013: ThinkMind, 2013, pp. 1-6

International Conference on Creative Content Technologies (CONTENT) <5, 2013, Valencia, Spain>

Automotive systems can be very complex when using multiple forms of energy. To achieve better energy efficiency, engineers require specialized tools to cope with that complexity and to comprehend how energy is spread and consumed. This is especially essential to develop hybrid systems, which generate electricity by various available forms of energy. Therefore, highly specialized visualizations of multiple measured energies are needed. This paper examines several three-dimensional glyph-based visualization techniques for spatial multivariate data. Besides animated glyphs, two-dimensional visualization techniques for temporal data to allow detailed trend analysis are considered as well. Investigations revealed that Scaled Data-Driven Spheres are best suited for a detailed 3D exploration of measured data. To gain a better overview of the spatial data, Cumulative Glyphs are introduced. For trend analysis, Theme River and Stacked Area Graphs are used. All these visualization techniques are implemented as a web-based prototype without the need of additional web browser plugins using X3DOM and Data-Driven Documents.

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Ullrich, Torsten; Silva, Nelson; Eggeling, Eva; Fellner, Dieter W.

Generative Modeling and Numerical Optimization for Energy Efficient Buildings

2013

IEEE Industrials Electronics Society: IECON 2013 - 39th Annual Conference of the IEEE Industrial Electronics Society. Proceedings. New York: IEEE Press, 2013, pp. 4756-4761

Annual Conference of the IEEE Industrial Electronics Society (IECON) <39, 2013, Vienna, Austria>

A procedural model is a script, which generates a geometric object. The script's input parameters offer a simple way to specify and modify the scripting output. Due to its algorithmic character, a procedural model is perfectly suited to describe geometric shapes with well-organized structures and repetitive forms. In this paper, we interpret a generative script as a function, which is nested into an objective function. Thus, the script's parameters can be optimized according to an objective. We demonstrate this approach using architectural examples: each generative script creates a building with several free parameters. The objective function is an energy-efficiency-simulation that approximates a building's annual energy consumption. Consequently, the nested objective function reads a set of building parameters and returns the energy needs for the corresponding building. This nested function is passed to a minimization and optimization process. Outcome is the best building (within the family of buildings described by its script) concerning energy-efficiency. Our contribution is a new way of modeling. The generative approach separates design and engineering: the complete design is encoded in a script and the script ensures that all parameter combinations (within a fixed range) generate a valid design. Then the design can be optimized numerically.

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Barmak, Katayun; Eggeling, Eva; Kinderlehrer, David; Sharp, Richard; Ta'asan, S.; Rollet, Anthony D.; Coffey, Kevin

Grain Growth and the Puzzle of its Stagnation in Thin Films: The Curious Tale of a Tail and an Ear

2013

Progress in Materials Science, Vol.58 (2013), 7, 987-1055

The underlying cause of stagnation of grain growth in thin metallic films remains a puzzle. Here it is re-visited by means of detailed comparison of experiments and simulations, using a broad range of metrics that, in addition to grain size, includes the number of sides and the average side class of nearest neighbors. The experimental grain size data reported is large and comprises nearly 35,000 grains from 27 thin film samples of Al and Cu with thicknesses in the range of 25 to 158 nm. The size distributions for the Al and Cu films are remarkably similar to each other despite the many and significant differences in experimental conditions, which include sputtering target purity, substrate type, film thickness, deposition temperature, actual as well as homologous annealing temperatures, annealing time, absolute grain size, and the twin density within the grains. This similarity argues for a universal experimental grain size distribution, which for grain diameters is lognormal as found previously for thin films at stagnation. Comparison of the experimental grain size distribution with that for two dimensional grain growth simulations with isotropic boundary energy shows the distributions to differ in two regions, termed the "ear" and the "tail". It is shown that the excess small grains in the region of the "ear" are primarily the 3 and 4-sided grains, whereas the excess of large grains in the "tail" region are grains with more than 9 sides. The excesses in the ear and tail regions of the experimental distributions are necessarily balanced by a deficiency in the mid-sized grains with 6-8 sides. Five causes are examined to identify the puzzling difference between simulations with isotropic boundary energy and experiments. These are (i) driving forces other than grain boundary energy reduction, (ii) anisotropy of grain boundary energy, (iii) grain boundary grooving, (iv) solute drag and (v) triple junction drag. No single cause is seen to provide an explanation for the observed experimental behavior. However, it is speculated that a combination of causes that include the anisotropy of grain boundary energy will be needed to explain the experimental behavior.

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Eggeling, Eva; Fellner, Dieter W.; Halm, Andreas; Ullrich, Torsten

Optimization of an Autostereoscopic Display for a Driving Simulator

2013

Coquillart, Sabine (Ed.) et al.: GRAPP 2013 - IVAPP 2013 : Proceedings of the International Conference on Computer Graphics Theory and Applications and International Conference on Information Visualization Theory and Applications. SciTePress, 2013, pp. 318-326

International Conference on Computer Graphics Theory and Applications (GRAPP) <8, 2013, Barcelona, Spain>

In this paper, we present an algorithm to optimize a 3D stereoscopic display based on parallax barriers for a driving simulator. The main purpose of the simulator is to enable user studies in reproducible laboratory conditions to test and evaluate driving assistance systems. The main idea of our optimization approach is to determine by numerical analysis the best pattern for an autostereoscopic display with the best image separation for each eye, integrated into a virtual reality environment. Our implementation uses a differential evolution algorithm, which is a parallel, direct search method based on evolution strategies, because it converges fast and is inherently parallel. This allows an execution on a network of computers. The resulting algorithm allows optimizing the display and its corresponding pattern, such that a single user in the simulator environment sees a stereoscopic image without being supported by special eye-wear.

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Eggeling, Eva; Fellner, Dieter W.; Ullrich, Torsten

Probability of Globality

2013

World Academy of Science, Engineering and Technology, Vol.73 (2013), pp. 483-487

The objective of global optimization is to find the globally best solution of a model. Nonlinear models are ubiquitous in many applications and their solution often requires a global search approach. This article presents a probabilistic approach to determine the probability of a solution being a global minimum. The approach is independent of the used global search method and only requires a limited, convex parameter domain A as well as a Lipschitz continuous function f whose Lipschitz constant is not needed to be known.

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Halm, Andreas; Eggeling, Eva; Fellner, Dieter W.

Embedding Biological Information in a Scene Graph System

2012

Linsen, Lars (Ed.) et al.: Visualization in Medicine and Life Sciences II : Progress and New Challenges. Berlin, Heidelberg, New York: Springer, 2012. (Mathematics and Visualization), pp. 249-264

We present the Bio Scene Graph (BioSG) for visualization of biomolecular structures based on the scene graph system OpenSG. The hierarchical model of primary, secondary and tertiary structures of molecules used in the organic chemistry is mapped to a graph of nodes when loading molecular files. We show that using BioSG, displaying molecules can be integrated in other applications, for example in medical applications. Additionally, existing algorithms and programs can be easily adapted to display the results with BioSG.

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Barmak, Katayun; Eggeling, Eva; Sharp, Richard; Roberts, Scott; Shyu, Terry; Sun, Tik; Yao, Bo; Ta'asan, Shlomo; Kinderlehrer, David; Rollett, Anthony; Coffey, Kevin

Grain Growth and the Puzzle of its Stagnation in Thin Films: A Detailed Comparison of Experiments and Simulations

2012

Materials Science Forum, Vol.Vol. 715-716 (2012), Recrystallization and Grain Growth IV, pp. 473-479

International Conference on Recrystallization and Grain Growth (ReX & GG) <4, 2010, Sheffield, UK>

We revisit grain growth and the puzzle of its stagnation in thin metallic films. We bring together a large body of experimental data that includes the size of more than 30,000 grains obtained from 23 thin film samples of Al and Cu with thicknesses in the range of 25 to 158 nm. In addition to grain size, a broad range of other metrics such as the number of sides and the average side class of nearest neighbors is used to compare the experimental results with the results of two dimensional simulations of grain growth with isotropic boundary energy. In order to identify the underlying cause of the differences between these simulations and experiments, five factors are examined. These are (i) surface energy and elastic strain energy reduction, (ii) anisotropy of grain boundary energy, and retarding and pinning forces such as (iii) solute drag, (iv) grain boundary grooving and (v) triple junction drag. No single factor provides an explanation for the observed experimental behavior.

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Barmak, Katayun; Eggeling, Eva; Emelianenko, Maria; Epshteyn, Yekaterina; Kinderlehrer, David; Sharp, Richard; Ta'asan, Shlomo

Predictive Theory for the Grain Boundary Character Distribution

2012

Materials Science Forum, Vol.Vol. 715-716 (2012), Recrystallization and Grain Growth IV, pp. 279-285

International Conference on Recrystallization and Grain Growth (ReX & GG) <4, 2010, Sheffield, UK>

Mesoscale experiment and simulation permit harvesting information about both geometric features and texture in material microstructures. The grain boundary character distribution (GBCD) is an empirical distribution of the relative length (in 2D) or area (in 3D) of interface with a given lattice misorientation and grain boundary normal. During the growth process, an initially random texture distribution reaches a steady state that is strongly correlated to the interfacial energy density. In simulation, it is found that if the given energy depends only on lattice misorientation, then the steady state GBCD and the energy are related by a Boltzmann distribution. This is among the simplest non-random distributions, corresponding to independent trials with respect to the energy. Why does such a simple distribution arise from such a complex system? We derive an entropy based theory which suggests that the evolution of the GBCD satisfies a Fokker-Planck Equation. Cellular structures coarsen according to a local evolution law, curvature driven growth, and are limited by space filling constraints. The interaction between the evolution law and the constraints is governed primarily by the force balance at triple junctions, the natural boundary condition associated to curvature driven growth, and determines a dissipation relation. A simplified coarsening model is introduced which is driven by the boundary conditions and reflects the network level dissipation relation of the grain growth system. It resembles an ensemble of inertia-free spring-mass-dashpots. Critical application is made of the recent characterization of Fokker-Planck kinetics as a gradient flow for a free energy in deriving the theory. The theory predicts the results of large scale 2D simulations and is consistent with experiment.

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Berndt, Rene; Settgast, Volker; Eggeling, Eva; Schinko, Christoph; Krispel, Ulrich; Havemann, Sven; Fellner, Dieter W.

Ring's Anatomy - Parametric Design of Wedding Rings

2012

Sehring, Hans-Werner et al.: CONTENT 2012 : The Fourth International Conference on Creative Content Technologies. ThinkMind, 2012, pp. 72-78

International Conference on Creative Content Technologies (CONTENT) <4, 2012, Nice, France>

We present a use case that demonstrates the effectiveness of procedural shape modeling for mass customization of consumer products. We show a metadesign that is composed of a few well-defined procedural shape building blocks. It can generate a large variety of shapes and covers most of a design space defined by a collection of exemplars, in our case wedding rings. We describe the process of model abstraction for the shape space spanned by these shapes, arguing that the same is possible for other shape design spaces as well.

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Hecher, Martin; Möstl, Robert; Eggeling, Eva; Derler, Christian; Fellner, Dieter W.

Tangible Culture - Designing Virtual Exhibitions on Multi-Touch Devices

2012

Baptista, Ana Alice (Ed.) et al.: Social Shaping of Digital Publishing: Exploring the Interplay Between Culture and Technology : Proceedings of the 16th International Conference on Electronic Publishing. Amsterdam; Berlin; Tokyo; Washington, DC: IOS Press, 2012, pp. 104-113

International Conference on Electronic Publishing (ELPUB) <16, 2012, Guimarães, Portugal>

Cultural heritage institutions such as galleries, museums and libraries increasingly use digital media to present artifacts to their audience and enable them to immerse themselves in a cultural virtual world. With the application eXhibition: editor3D museum curators and editors have a software tool at hand to interactively plan and visualize exhibitions. In this paper we present an extension to the application that enhances the workflow when designing exhibitions. By introducing multi-touch technology to the graphical user interfaces the designing phase of an exhibition is efficiently simplified, especially for non-technical users. Furthermore, multi-touch technology offers a novel way of collaborative work to be integrated into a decision making process. A flexible export system allows to store created exhibitions in various formats to display them on websites, mobile devices or custom viewers. E.g. the widespread 3D scene standard Extensible 3D (X3D) is one of the export formats and we use it to directly incorporate a realtime preview of the exhibition in the authoring process. The combination of the tangible user interfaces with the realtime preview gives curators and exhibition planers a capable tool for efficiently presenting cultural heritage in electronic media.

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Hecher, Martin; Möstl, Robert; Eggeling, Eva; Derler, Christian

Tangible Culture - Designing Virtual Exhibitions on Multi-touch Devices

2012

Schenk, Michael (Ed.): 15. IFF-Wissenschaftstage 2012. Tagungsband : Digitales Engineering zum Planen, Testen und Betreiben technischer Systeme. Stuttgart: Fraunhofer Verlag, 2012, pp. 237-243

IFF-Wissenschaftstage <15, 2012, Magdeburg, Germany>

Cultural heritage institutions such as galleries, museums and libraries increasingly use digital media to present artifacts to their audience and enable them to immerse in a cultural virtual world. With the application eXhibition: editor3D museum curators and editors have a software tool at hand to interactively plan and visualize exhibitions. In this paper we present an extension to the application that enhances the workflow when designing exhibitions. By introducing multi-touch technologies to the graphical user interfaces the designing phase of an exhibition is efficiently simplified, especially for nontechnical users. Furthermore, multi-touch technologies offer a novel way of collaborative work to be integrated in a decision making process. The widespread 3D scene standard Extensible 3D (X3D) is used as the export format. In using X3D the resulting exhibitions are highly versatile. We show this versatility in directly using X3D's external authoring interface to integrate a realtime preview of the exhibition in the authoring phase. The combination of the tangible user interfaces with the realtime preview gives curators and editors a capable tool for efficiently presenting cultural heritage to a wide audience.

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Settgast, Volker; Eggeling, Eva; Fellner, Dieter W.

The Preparation of 3D-Content for Interactive Visualization

2012

Schenk, Michael (Ed.): 15. IFF-Wissenschaftstage 2012. Tagungsband : Digitales Engineering zum Planen, Testen und Betreiben technischer Systeme. Stuttgart: Fraunhofer Verlag, 2012, pp. 187-192

IFF-Wissenschaftstage <15, 2012, Magdeburg, Germany>

The presentation of 3D content is an essential part of many industrial and scientific projects. Interactive visualizations are much more useful than images and pre-rendered videos. But the creation process can be an important cost factor. Further-more, the outcome of such visualizations has to compete with state of the art computer games. It is not sufficient for interactive presentations to have the 3D content and the rendering software. The content has to be modified. In the best case the data only has to be converted to be understood by the presentation application. This task can be automated by conversion software. But in most cases the content has to be modified beyond that. Optimized scenes for interactive rendering are hardly created automatically and the modification is a time and cost-intensive procedure. Suitable measures to reduce the time and cost effort are described in this article.

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Hecher, Martin; Möstl, Robert; Eggeling, Eva; Derler, Christian; Fellner, Dieter W.

"Tangible Culture" - Designing Virtual Exhibitions on Multi-touch Devices

2011

Information Services & Use, Vol.31 (2011), 3-4, pp.199-208

Cultural heritage institutions such as galleries, museums and libraries increasingly use digital media to present artifacts to their audience and enable them to immerse in a cultural virtual world. With the application eXhibition: editor3D museum curators and editors have a software tool at hand to interactively plan and visualize exhibitions. In this paper we present an extension to the application that enhances the workflow when designing exhibitions. By introducing multi-touch technologies to the graphical user interfaces the designing phase of an exhibition is efficiently simplified, especially for nontechnical users. Furthermore, multi-touch technologies offer a novel way of collaborative work to be integrated in a decision making process. The widespread 3D scene standard Extensible 3D (X3D) is used as the export format. In using X3D the resulting exhibitions are highly versatile. We show this versatility in directly using X3D's external authoring interface to integrate a realtime preview of the exhibition in the authoring phase. The combination of the tangible user interfaces with the realtime preview gives curators and editors a capable tool for efficiently presenting cultural heritage to a wide audience.

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Barmak, Katayun; Eggeling, Eva; Emelianenko, Maria; Epshteyn, Yekaterina; Kinderlehrer, David; Sharp, Richard; Ta'asan, Shlomo

An Entropy Based Theory of the Grain Boundary Character Distribution

2011

Discrete and Continuous Dynamical Systems / Series A, Vol.30 (2011), 2, pp. 427-454

Cellular networks are ubiquitous in nature. They exhibit behavior on many different length and time scales and are generally metastable. Most technologically useful materials are polycrystalline microstructures composed of a myriad of small monocrystalline grains separated by grain boundaries. The energetics and connectivity of the grain boundary network plays a crucial role in determining the properties of a material across a wide range of scales. A central problem in materials science is to develop technologies capable of producing an arrangement of grains a texture appropriate for a desired set of material properties. Here we discuss the role of energy in texture development, measured by a character distribution. We derive an entropy based theory based on mass transport and a Kantorovich-Rubinstein-Wasserstein metric to suggest that, to first approximation, this distribution behaves like the solution to a Fokker-Planck Equation.

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Barmak, Katayun; Eggeling, Eva; Emelianenko, Maria; Epshteyn, Yekaterina; Kinderlehrer, David; Sharp, Richard; Ta'asan, Shlomo

Critical Events, Entropy, and the Grain Boundary Character Distribution

2011

Physical Review B, Vol.83 (2011), 13, pp. 134117-1 - 134117-12

Mesoscale experiment and simulation permit harvesting information about both geometric features and texture in polycrystals. The grain boundary character distribution (GBCD) is an empirical distribution of the relative length (in 2D) or area (in 3D) of interface with a given lattice misorientation and normal. During the growth process, an initially random distribution reaches a steady state that is strongly correlated to the interfacial energy density. In simulation, it is found that if the given energy density depends only on lattice misorientation, then the steady state GBCD and the energy are related by a Boltzmann distribution. This is among the simplest non-random distributions, corresponding to independent trials with respect to the energy. Why does such a simple distribution arise from such a complex system? We derive an entropy based theory which suggests that the evolution of the GBCD satisfies a Fokker-Planck Equation. Cellular structures coarsen according to a local evolution law, curvature driven growth, and are limited by space filling constraints. The interaction between the evolution law and the constraints is governed primarily by the force balance at triple junctions, the natural boundary condition associated to curvature driven growth, and determines a dissipation relation. A simplified coarsening model is introduced which is driven by the boundary conditions and reflects the network level dissipation relation of the grain growth system. It resembles an ensemble of inertia-free spring-mass-dashpots. Critical application is made of the recent characterization of Fokker-Planck kinetics as a gradient flow for a free energy in deriving the theory. The theory predicts the results of large scale 2D simulations and is consistent with experiment.

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Breuel, Frank; Berndt, Rene; Ullrich, Torsten; Eggeling, Eva; Fellner, Dieter W.

Mate in 3D - Publishing Interactive Content in PDF3D

2011

Tonta, Yasar (Ed.) et al.: Digital Publishing and Mobile Technologies : 15th International Conference on Electronic Publishing [online]. Ankara: Hacettepe University Department of Information Management, 2011, pp. 110-119

International Conference on Electronic Publishing (ELPUB) <15, 2011, Istanbul, Turkey>

In this paper we describe a pipeline for publishing interactive multimedia content. The Portable Document Format (PDF) offers the possibility to include 3D visualizations, textual representation and interactivity (via scripting technology) in one multimedia container, which will be the upcoming standard for multimedia long-term archiving. Our system demonstrates its potential for surplus value eBooks. By the example of chess we developed a publishing pipeline to create interactive books. Usually, chess games and positions are recorded using the algebraic chess notation, which is mainly an annotated list of moves. In combination with a time-dependent 3D visualization, each move corresponds to a specific game position. This correspondence is encoded in hyperlinks from the textual representation to the 3D visualization. This linkage improves readability and usability of chess notations significantly. Furthermore, using an established file format our eBooks can be opened by any compliant PDF viewer.

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Hecher, Martin; Möstl, Robert; Eggeling, Eva; Derler, Christian; Fellner, Dieter W.

Tangible Culture - Designing virtual Exhibitions on Multi-Touch Devices

2011

Ercim News, (2011), 86, pp. 21-22

Cultural heritage institutions such as galleries, museums and libraries increasingly use digital media to present artifacts to their audience and enable them to immerse themselves in a cultural virtual world. With the application eXhibition:editor3D, museum curators and editors have a software tool at hand to interactively plan and visualize exhibitions. The software is running on standard PCs as well as multi-touch devices, which allow a user to utilize intuitive gestures for positioning exhibition objects. Furthermore, multi-touch technology offers the integration of collaborative work into a decision making process.

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Eggeling, Eva; Barmak, Katayun; Emelianenko, Maria; Epshteyn, Yekaterina; Kinderlehrer, David; Ta'asan, Shlomo

Geometric Growth and Character Development in Large Metastable Networks

2009

Rendiconti di matematica e delle sue applicazioni, Vol.29 (2009), 1, pp. 65-81

Cellular networks are ubiquitous in nature. They exhibit behavior on many different length and time scales and are generally metastable. Most technologically useful materials are polycrystalline microstructures composed of a myriad of small monocrystalline grains separated by grain boundaries. The energetics and connectivity of the grain boundary network plays a crucial role in determining the properties of a material across a wide range of scales. A central problem in materials science is to develop technologies capable of producing an arrangement of grains - a texture - that provides for a desired set of material properties. Here we discuss briefly the role of energy in texture development, measured by a character distribution, and how this is different from the evolution of geometric features, which we term geometric coarsening. For this purpose we present a critical event model to deepen our understanding of the topological reconfigurations that occur during the growth process.