Vienna University of Technology

About: Vienna University of Technology is a education organization based out in Vienna, Austria. It is known for research contribution in the topics: Laser & Context (language use). The organization has 16723 authors who have published 49341 publications receiving 1302168 citations.

Comprehensive study of the vapour–liquid coexistence of the truncated and shifted Lennard–Jones fluid including planar and spherical interface properties

Abstract: Vapour–liquid equilibria of the Lennard–Jones potential, truncated and shifted at 2.5σ, are studied using molecular dynamics simulations, an attractive option for studying inhomogeneous systems. Comprehensive simulation data are reported for three cases: no interface, a planar interface, and a spherical interface between the coexisting phases, covering a wide range of temperatures. Spherical droplets are also studied for a range of radii between 5 and 16σ. The size dependence of the surface tension, based on the Irving–Kirkwood pressure tensor, and other properties is quantified for spherical interfaces. All simulation results are correlated with a consistent set of empirical equations. A comparison with the results of other authors as well as with experimental data for noble gases and methane is also presented.

Cohesive, structural, and electronic properties of fe-si compounds

Abstract: Phase stability, structural, and electronic properties of iron silicides in the ${\mathrm{Fe}}_{3}\mathrm{Si},$ FeSi, and ${\mathrm{FeSi}}_{2}$ compositions are investigated by first-principle density-functional calculations based on ultrasoft pseudopotentials and all-electron methods. Structural stabilization versus spin-polarization effects are discussed at the ${\mathrm{Fe}}_{3}\mathrm{Si}$ composition, while for \ensuremath{\epsilon}-FeSi and $\ensuremath{\beta}\ensuremath{-}{\mathrm{FeSi}}_{2}$ we investigate their structural properties and the corresponding semiconducting band properties. All the computed results are analyzed and compared to available experimental data. The stability of the bulk phases, the lattice parameters, the cohesive energies and magnetic properties are found to be in good agreement with experiment when using the generalized gradient approximations for the exchange-correlation functional. Density-functional calculations are unable to account for the small bulk modulus of $\ensuremath{\epsilon}\ensuremath{-}\mathrm{FeSi}$ despite that the computed lattice constant and internal atomic positions coincide with the experimental results. Both full-potential and ultrasoft-pseudopotential methods confirm for $\ensuremath{\beta}\ensuremath{-}{\mathrm{FeSi}}_{2}$ the indirect nature of the fundamental gap, which is attributed to a transition between Y to 0.6\ifmmode\times\else\texttimes\fi{}\ensuremath{\Lambda} being 30% smaller than the experimental gap. Ultrasoft pseudopotential calculations of Fe-Si magnetic phases and of various nonequilibrium metallic phases at the FeSi and ${\mathrm{FeSi}}_{2}$ composition are presented. These calculations provide ab initio information concerning the stabilization of metallic pseudomorphic phases via high pressures or epitaxy.

Comparison, Selection, and Parameterization of Electrical Battery Models for Automotive Applications

Abstract: This paper describes the comparison and parameterization process of dynamic battery models for cell and system simulation. Three commonly used equivalent circuit battery models are parameterized using a numeric optimization method and basic electrical tests with a lithium-ion polymer battery cell. The maximum model performance is investigated, and the parameterized models are compared regarding the parameterization effort and the model accuracy. For the model with the best tradeoff between the parametrization effort and the model accuracy, a reasonable simplification of the parameterization process is presented. This model is parameterized with the simplified parameterization process and, finally, validated by using a current profile obtained from an electric vehicle simulation performing a real-life driving cycle.

Comparison of three-dimensional surface-imaging systems

Abstract: Summary Background In recent decades, three-dimensional (3D) surface-imaging technologies have gained popularity worldwide, but because most published articles that mention them are technical, clinicians often have difficulties gaining a proper understanding of them. This article aims to provide the reader with relevant information on 3D surface-imaging systems. In it, we compare the most recent technologies to reveal their differences. Methods We have accessed five international companies with the latest technologies in 3D surface-imaging systems: 3dMD, Axisthree, Canfield, Crisalix and Dimensional Imaging (Di3D; in alphabetical order). We evaluated their technical equipment, independent validation studies and corporate backgrounds. Results The fastest capturing devices are the 3dMD and Di3D systems, capable of capturing images within 1.5 and 1 ms, respectively. All companies provide software for tissue modifications. Additionally, 3dMD, Canfield and Di3D can fuse computed tomography (CT)/cone-beam computed tomography (CBCT) images into their 3D surface-imaging data. 3dMD and Di3D provide 4D capture systems, which allow capturing the movement of a 3D surface over time. Crisalix greatly differs from the other four systems as it is purely web based and realised via cloud computing. Conclusion 3D surface-imaging systems are becoming important in today's plastic surgical set-ups, taking surgeons to a new level of communication with patients, surgical planning and outcome evaluation. Technologies used in 3D surface-imaging systems and their intended field of application vary within the companies evaluated. Potential users should define their requirements and assignment of 3D surface-imaging systems in their clinical as research environment before making the final decision for purchase.