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Data are often subject to some degree of uncertainty, whether aleatory or epistemic. This applies both to experimental data acquired with sensors as well as to simulation data. Displaying these data and their uncertainty faithfully is crucial for gaining knowledge. Specifically, the effective communication of the uncertainty can influence the interpretation of the data and the user's trust in the visualization. However, uncertainty-aware visualization has gotten little attention in molecular visualization. When using the established molecular representations, the physicochemical attributes of the molecular data usually already occupy the common visual channels like shape, size, and color. Consequently, to encode uncertainty information, we need to open up another channel by using feature lines. Even though various line variables have been proposed for uncertainty visualizations, they have so far been primarily used for two-dimensional data and there has been little perceptual evaluation. Thus, we conducted two perceptual studies to determine the suitability of the line variables blur, dashing, grayscale, sketchiness, and width for distinguishing several values in molecular visualizations. While our work was motivated by uncertainty visualization, our techniques and study results also apply to other types of scalar data. [Display omitted] • Novel uncertainty-aware visualization for biomolecules using feature lines. • Data on surfaces is visualized without occupying commonly-used visual channels. • The line attributes of stylizable lines are varied to encode scalar values. • Perceptual evaluation of blur, dashing, grayscale, sketchiness, and width. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new photocatalytic coating with superior activity for NO, NO 2 and HONO was developed. • High photocatalytic abatement was observed in the laboratory for all expected tunnel conditions. • A photocatalytic prototype reactor was developed and tested under realistic tunnel conditions. • NO x abatement of the whole tunnel exhaust of 45–80 % is expected in a real tunnel application. In the TunNOx project a highly efficient photocatalytic reactor was developed, which can be integrated into transverse ventilation systems of road tunnels. First, an active photocatalytic coating was developed and tested in the laboratory at variable reactant concentrations, humidity, temperature and irradiance levels. Superior abatement of nitrogen oxides (NO x) and nitrous acid (HONO) was observed even at high NO x levels, low temperature and high humidity, which are typically not beneficial in photocatalysis. Second, by using a porous photocatalytically coated mesh, a prototype reactor was developed, which was adapted to the conditions typically prevailing in tunnel ventilation systems and which could be used as one segment of a larger reactor. Based on experimental results of the abatement of NO, NO 2 and diesel exhaust in the prototype reactor a simple model was developed by which NO x abatement of 45–80 % is calculated for typical road tunnel conditions. [ABSTRACT FROM AUTHOR]

This article describes a detailed investigation of the flow at the entry of a twin-belt caster, combining non-intrusive flow velocity measurements via Particle-Image Velocimetry (PIV) with detailed numerical simulations based on Computational Fluid Dynamics (CFD). The experimental set up includes a tundish, a stopper, a Submerged Entry Nozzle (SEN), and the walls of the twin-belt caster. Similarity theory was used to build an appropriate water model. The water level in between the horizontal belts is controlled by the height of the fully functional stopper. Detailed experimental measurements deliver the velocity distribution at the outlet of the SEN and are used to characterize the jet between the belts. The simulation identically reproduces this model providing a direct comparison. Two different turbulence models are applied in CFD simulations. The differences found between the results provide interesting insights. The k-ω-SST turbulence model delivers a much better agreement and is thus recommended for future studies. It is also found that, due to the very complex flow structures appearing around the stopper head, the full geometry must be considered in the simulation. Slow fluctuations are observed both in the course of the experiments and CFD, which is why meaningful comparisons are only possible for time-averaged quantities. Finally, a very good agreement is obtained between the measurements and the simulations, opening the door to further studies regarding caster flow homogeneity. [ABSTRACT FROM AUTHOR]

In this paper, we present a parameterization technique that can be applied to surface meshes in real-time without time-consuming preprocessing steps. The parameterization is suitable for the display of (un-)oriented patterns and texture patches, and to sample a surface in a periodic fashion. The method is inspired by existing work that solves a global optimization problem to generate a continuous stripe pattern on the surface, from which texture coordinates can be derived. We propose a local optimization approach that is suitable for parallel execution on the GPU, which drastically reduces computation time. With this, we achieve on-the-fly texturing of 3D, medium-sized (up to 70 k vertices) surface meshes. The algorithm takes a tangent vector field as input and aligns the texture coordinates to it. Our technique achieves real-time parameterization of the surface meshes by employing a parallelizable local search algorithm that converges to a local minimum in a few iterations. The calculation in real-time allows for live parameter updates and determination of varying texture coordinates. Furthermore, the method can handle non-manifold meshes. The technique is useful in various applications, e.g., biomedical visualization and flow visualization. We highlight our method’s potential by providing usage scenarios for several applications. [ABSTRACT FROM AUTHOR]

• We extend our tool focusing on the evaluation of depth perception to include the evaluation of shape perception. • We extend the generation of task-based experiments based on vascular surface models to arbitrary surfaces models. • We provide an automatic preparation of web-based studies to evaluate depth and shape perception in visualization techniques. User studies are indispensable for visualization application papers in order to assess the value and limitations of the presented approach. Important aspects are how well depth and shape information can be perceived, as coding of these aspects is essential to enable an understandable representation of complex 3D data. In practice, there is usually little time to perform such studies, and the establishment and conduction of user studies can be labour-intensive. In addition, it can be difficult to reach enough participants to obtain expressive results regarding the quality of different visualization techniques. In this paper, we propose a framework that allows visualization researchers to quickly create task-based user studies on depth and shape perception for different surface visualizations and perform the resulting tasks via a web interface. With our approach, the effort for generating user studies is reduced and at the same time the web-based component allows researchers to attract more participants to their study. We demonstrate our framework by applying shape and depth evaluation tasks to visualizations of various surface representations used in many technical and biomedical applications. [ABSTRACT FROM AUTHOR]

Abstract: The spray Ion Layer Gas Reaction (ILGAR) process starts with ultrasonic nebulisation of the precursor solution, e.g. InCl3/ethanol for our successful buffer material In2S3. In an aerosol assisted chemical vapour deposition (AACVD) type reaction an In(O,OH,Cl) film is deposited on a heated substrate and is subsequently converted to In2S3 by H2S gas. The cycle of these steps is repeated until the required layer thickness is obtained. The robust and reproducible process allows a wide control of composition and morphology. Results of this “spray-ILGAR” method with respect to process, material properties and its application depositing the buffer layer in chalcopyrite solar cells are reviewed. New aspects such as the investigation of the complex chemical mechanism by mass spectrometry, the process acceleration by the addition of H2S gas to the aerosol, the controlled deposition of ZnS nano-dot films and finally the latest achievements in process up-scaling are also included. Solar cells based on industrial Cu(In,Ga)(S,Se)2 absorbers (Avancis GmbH) with a Spray-ILGAR In2S3 buffer reached 14.7% efficiency (certified) and 15.3% with a ZnS/In2S3 bi-layer buffer comparable to reference cells using standard CdS buffer layers deposited by chemical bath deposition (CBD). The quasi-dry, vacuum-free ILGAR method for In2S3 buffer layers is well suited for industrial in-line production and is capable of not only replacing the standard buffer material (the toxic CdS) but also the often slow CBD process. A tape coater for 10cm wide steel tape was constructed. It was shown that In2S3 layers could be produced with an indium yield better than 30% and a linear production speed of 1m/min. A roll-to-roll pilot production line for electrochemically deposited Cu(In,Ga)Se2 with ILGAR buffer is running in industry (CIS-Solartechnik, Hamburg). A 30x30cm2 prototype of an ILGAR in-line coater developed by Singulus and Helmholtz Zentrum Berlin is currently being optimised. First 30×30cm2 encapsulated modules achieved efficiencies up to 13.0% (CdS buffered reference 13.3%). [Copyright &y& Elsevier]