Search Results - "Römer, Ulrich"

Failing parametrizations: what can go wrong when approximating spectral submanifolds by Stoychev, Alexander K., Römer, Ulrich J.

“…Invariant manifolds provide useful insights into the behavior of nonlinear dynamical systems. For conservative vibration problems, Lyapunov subcenter manifolds…”
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An adaptive sparse grid rational Arnoldi method for uncertainty quantification of dynamical systems in the frequency domain by Römer, Ulrich, Bollhöfer, Matthias, Sreekumar, Harikrishnan, Blech, Christopher, Christine Langer, Sabine

“…In this paper, we address discrete linear systems in the frequency domain, where both frequency and random parameters are considered. Sampling such a system…”
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Optimization of energy efficiency of walking bipedal robots by use of elastic couplings in the form of mechanical springs by Bauer, Fabian, Römer, Ulrich, Fidlin, Alexander, Seemann, Wolfgang

“…This paper presents a method to optimize the energy efficiency of walking bipedal robots by more than 50 % in a speed range from 0.3 to 2.3 m / s using elastic…”
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Design of Fuel Cell Systems for Aviation: Representative Mission Profiles and Sensitivity Analyses by Kadyk, Thomas, Schenkendorf, René, Hawner, Sebastian, Yildiz, Bekir, Römer, Ulrich

“…The global transition to a clean and sustainable energy infrastructure does not stop at aviation. The European Commission defined a set of environmental goals…”
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Low-Dimensional Stochastic Modeling of the Electrical Properties of Biological Tissues by Romer, Ulrich, Schmidt, Christian, Van Rienen, Ursula, Schops, Sebastian

“…Uncertainty quantification plays an important role in biomedical engineering as measurement data are often unavailable and literature data show a wide…”
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High‐dimensional uncertainty quantification for an electrothermal field problem using stochastic collocation on sparse grids and tensor train decompositions by Loukrezis, Dimitrios, Römer, Ulrich, Casper, Thorben, Schöps, Sebastian, De Gersem, Herbert

“…Summary The temperature developed in bondwires of integrated circuits (ICs) is a possible source of malfunction and has to be taken into account during the…”
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Intramuscular Bioavailability and Clinical Efficacy of Artesunate in Gabonese Children with Severe Malaria by NEALON, Claire, DZEING, Arnaud, MÜLLER-RÖMER, Ulrich, PLANCHE, Timothy, SINOU, Veronique, KOMBILA, Maryvonne, KREMSNER, Peter G, PARZY, Daniel, KRISHNA, Sanjeev

“…Classifications Services AAC Citing Articles Google Scholar PubMed Related Content Social Bookmarking CiteULike Delicious Digg Facebook Google+ Mendeley Reddit…”
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A rational ansatz for the approximation of Koopman eigenfunctions by Römer, Ulrich J., Breitenhuber, Margarete

“…Koopman operator theory offers a basis for the systematic transformation and linearization of complex dynamical systems. We propose a method to approximate…”
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Stochastic phase-field modeling of brittle fracture: Computing multiple crack patterns and their probabilities by Gerasimov, Tymofiy, Römer, Ulrich, Vondřejc, Jaroslav, Matthies, Hermann G., De Lorenzis, Laura

“…In variational phase-field modeling of brittle fracture, the functional to be minimized is not convex, so that the necessary stationarity conditions of the…”
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Deterministic and stochastic phase-field modeling of anisotropic brittle fracture by Nagaraja, Sindhu, Römer, Ulrich, Matthies, Hermann G., De Lorenzis, Laura

“…We investigate variational phase-field formulations of anisotropic brittle fracture to model zigzag crack patterns in cubic materials. Our objective is…”
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Balancing modeling and discretization errors in the numerical approximation of magnetostatic fields with uncertainties by Romer, Ulrich, De Gersem, Herbert

“…This work is concerned with error control in the numerical approximation of magnetic fields. It is shown how linearization and discretization error can be…”
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Approximation of Moments for the Nonlinear Magnetoquasistatic Problem With Material Uncertainties by Romer, Ulrich, Schops, Sebastian, Weiland, Thomas

“…In this paper, we study the magnetoquasistatic problem with uncertainties in the nonlinear magnetic material characteristic. In the case of small input…”
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An hp‐adaptive multi‐element stochastic collocation method for surrogate modeling with information re‐use by Galetzka, Armin, Loukrezis, Dimitrios, Georg, Niklas, De Gersem, Herbert, Römer, Ulrich

“…This article introduces an hp$$ hp $$‐adaptive multi‐element stochastic collocation method, which additionally allows to re‐use existing model evaluations…”
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Comparing frequentist and Bayesian uncertainty quantification in two‐step constitutive model calibration by Tröger, Jendrik‐Alexander, Römer, Ulrich, Hartmann, Stefan

“…The calibration of constitutive models using experimental observations is a well‐established task in computational solid mechanics. Especially for complex…”
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Inferring displacement fields from sparse measurements using the statistical finite element method by B. Narouie, Vahab, Wessels, Henning, Römer, Ulrich

“…Nowadays, strain and displacement can be measured using techniques such as electronic speckle pattern interferometry and digital image correlation. However,…”
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Determination of bond wire failure probabilities in microelectronic packages by Casper, Thorben, Romer, Ulrich, Schops, Sebastian

“…This work deals with the computation of industry-relevant bond wire failure probabilities in microelectronic packages. Under operating conditions, a package is…”
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The normal parameterization and its application to collision detection by Römer, Ulrich J., Fidlin, Alexander, Seemann, Wolfgang

“…•A new parameterization for two- and three-dimensional geometries.•Limited to strictly convex geometries.•Simple, easy-to-use formulas for position, normals,…”
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Surrogate‐based Bayesian calibration of biomechanical models with isotropic material behavior by Römer, Ulrich, Liu, Jintian, Böl, Markus

“…This work introduces a computational methodology to calibrate material models in biomechanical applications under uncertainty. We adopt a Bayesian approach,…”
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Explicit analytical solutions for two-dimensional contact detection problems between almost arbitrary geometries and straight or circular counterparts by Römer, Ulrich J., Fidlin, Alexander, Seemann, Wolfgang

“…•A new parameterization for planar geometries is introduced.•Geometries with arbitrary complexity can be described.•The approach gives explicit solutions for…”
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A discrete contact model for complex arbitrary-shaped convex geometries by Marquardt, Jan E., Römer, Ulrich J., Nirschl, Hermann, Krause, Mathias J.

“…The shape of particles has a significant influence on the behavior of suspensions, as the particle-fluid, particle-particle, and particle-wall interactions…”
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