A5085070208- Advanced Numerical Analysis Techniques
- Numerical methods in engineering
- Electromagnetic Scattering and Analysis
- Advanced Numerical Methods in Computational Mathematics
- Magnetic Properties and Applications
- Piezoelectric Actuators and Control
- Electromagnetic Simulation and Numerical Methods
- Polynomial and algebraic computation
- Parallel Computing and Optimization Techniques
- Geodetic Measurements and Engineering Structures
- Structural Health Monitoring Techniques
- Cloud Computing and Resource Management
- Computational Geometry and Mesh Generation
- semigroups and automata theory
- Distributed systems and fault tolerance
- Electric Motor Design and Analysis
- Iterative Methods for Nonlinear Equations
- Computability, Logic, AI Algorithms
- Advanced Data Storage Technologies
- Aeroelasticity and Vibration Control
- Advanced Neural Network Applications
- Distributed and Parallel Computing Systems
- Shape Memory Alloy Transformations
- Software System Performance and Reliability
- Neural Networks and Applications
Technical University of Darmstadt
2017-2025
Felix Scholarship
2018
Friedrich-Alexander-Universität Erlangen-Nürnberg
1964-2014
We analyze a new approach to three-dimensional electromagnetic scattering problems via fast isogeometric boundary element methods. Starting with an investigation of the theoretical setting around electric field integral equation within framework, we show existence, uniqueness, and quasi optimality approach. For efficient computation, then introduce interpolation-based multipole method tailored setting, which admits competitive algorithmic complexity properties. This is followed by series...
This contribution investigates the connection between isogeometric analysis and integral equation methods for full-wave electromagnetic problems up to low-frequency limit. The proposed spline-based method allows an exact representation of model geometry described in terms non-uniform rational B-splines without meshing. is particularly useful when high accuracy required or meshing cumbersome instance during optimization electric components. augmented field adopted deflation applied, so...
In this article, we present Bembel, the C++ library featuring higher order isogeometric Galerkin boundary element methods for Laplace, Helmholtz, and Maxwell problems. Bembel is compatible with geometries from Octave NURBS package, provides an interface to Eigen template linear algebra operations. For computational efficiency, it applies embedded fast multipole method tailored analysis framework a parallel matrix assembly based on OpenMP.
We discuss numerical experiments to compare an isogeometric discretization of the electric field integral equation and a parametric Raviart-Thomas approach. Therein, we focus on accuracy with respect degrees freedom, briefly commenting conditioning system as well. Due utilization mappings even in approach, our investigation disregards any errors induced by meshing, which commonly favors approach when compared curvilinear higher order elements.
This paper proposes a numerical discrete formulation for an inverted hysteresis model, which is based on the classic Preisach but applies switch operator. The operator modified from of model. By applying this operator, model retains wiping-out and congruency properties. distribution weight function can be approximated with analytical function. means quasi-Newton method algorithm, small number parameters in directly determined major loops. Iterative procedure circumvented implementation...
We present a model for the simulation of ferroelectric hysteresis loops. It is based on Preisach operator and takes advantage an analytic weight function underlying fundamental switching operators. The five independent parameters describing this are determined discoidal piezoceramic actuator by adapting output to measurements polarization. Further simulations, performed using adapted compared actuator. To consider time dependent behavior domains, our furthermore extended drift verified means...
This contribution investigates the connection between Isogeometric Analysis and Integral Equation methods for full-wave electromagnetic problems. The proposed spline-based integral equation method allows an exact representation of model geometry described in terms Non-Uniform Rational B-Splines without meshing. is particularly useful when high accuracy required or meshing cumbersome instance during optimization electric components. Augmented Electric Field adopted, so low-frequency breakdown...
The reliability of Finite Element based simulations the electrical and mechanical behavior for piezoceramic actuators strongly depends on accuracy required material parameters. For many transducer shapes, standard methods in order to determine parameters are not applicable. Therefore, we developed an alternative method parameter estimation, namely Inverse Method. With aid this method, deviation simulation from measurement results is minimized. In article, present extended Method, which...
We solve Maxwell's eigenvalue problem via isogeometric boundary elements and a contour integral method. discuss the analytic properties of discretisation, outline implementation, showcase numerical examples.
In various ferroelectric actuator applications, the active material is exposed to mechanical prestress. This often caused by unintended clamping, such as for smart materials with embedded components. other cases, stress applied on purpose enhance transducer performance or prevent from tensile forces. Hence, development of models, describing behavior under combined, electro-mechanical loading conditions essential. our previous work, we proposed an analytic weight function scalar Preisach...
The main objective of the ADMIRE project1 is creation an active I/O stack that dynamically adjusts computation and storage requirements through intelligent global coordination, elasticity I/O, scheduling resources along all levels hierarchy, while offering quality-of-service (QoS), energy efficiency, resilience for accessing extremely large data sets in very heterogeneous computing environments. We have developed a framework prototype able to adjust separated control, paths, malleability...
In our previous work, we proposed an enhanced iterative scheme for the piezoelectric material parameter identification based on finite element simulation and measurements of electrical impedance. We extended allow now further parameters a transducer assembly. Here, is first applied to single piezoceramic disc. The results process are verified by comparison between surface velocity second step, updated used as initial values transducer, at which disc combined with two matching layers. Sound...
Convolution operations are essential constituents of convolutional neural networks. Their efficient and performance-portable implementation demands tremendous programming effort fine-tuning. Winograd's minimal filtering algorithm is a well-known method to reduce the computational complexity convolution operations. Unfortunately, existing implementations this either vendor-specific or hard-coded support small subset convolutions, thus limiting their versatility performance portability. In...
In order to compensate for hysteresis errors in tracking and manipulation tasks, models describing the piezoceramic actuator nonlinearities are required. These have meet following two criteria: (i) Efficiency (ii) a bidirectional description of phenomena. Due its flexibility efficiency, Preisach operator is promising tool model transfer behavior ferroelectric actuators forward direction. However, cannot be inverted analytically. The scope this contribution therefore introduce novel,...