Themenvorschläge

9 Einträge gefunden. Alle Arbeiten anzeigen.

• 2019

  Mode Classification for Cavities using Eigenvalue Tracking

  Bachelorarbeit

  Eigenmodes of accelerator cavities are cataloged based on their electromagnetic fieldsin order to analyze the performance of the device. The nomenclature is originally definedfor cylindrical pillbox cavities where the eigenfrequencies and corresponding fielddistributions are known analytically. Due to the complex shape of real-world cavities,in practice the eigenmodes need to be determined using numerical simulations. Theattempt to automatically classify eigenmodes by post-processing the numerical fieldsolution is still cumbersome [1]. Therefore, the focus of this work is to investigate automaticmode recognition by deforming the cavity geometry to a pillbox and trackingthe eigenmodes during the deformation. weiter

  Betreuer/innen: Niklas Georg, M.Sc., Prof. Dr. rer. nat. Sebastian Schöps

  Ausschreibung als PDF

• 2019

  Modeling and Simulation of Magnetostrictive Effects in EAS tag using FEM/IGA

  Bachelorarbeit

  Magnetostrictive Electronic Article Surveillance Tags (EAS) are a common tool to prevent shoplifting and make use of the magnetoelastic coupling to convert electromagnetic energy into mechanical energy and vice versa. They usually consist of thin magnetostrictive metal strips (see Fig. 1) that vibrate once exposed to the magnetic field at the exit of the shop. This, in turn, changes the magnetization of the strip, inducing an AC voltage and activating an alarm in the detector. weiter

  Betreuer/innen: Dr. rer. nat Mané Harutyunyan , Prof. Dr. rer. nat. Sebastian Schöps

  Ausschreibung als PDF

• 2019

  Pareto Optimization for Failure Probability

  Bachelorarbeit

  Deviations in the manufacturing process of electronic components may lead to rejections due to malfunctioning. Uncertain design variables can be modeled as random variables. Then, the probability that a product fulfills its performance feature specifications is called the yield. The aim of our research is to estimate the yield and then maximizing the yield, which corresponds to minimizing the failure probability. weiter

  Betreuer/innen: Mona Fuhrländer, M.Sc., Prof. Dr. rer. nat. Sebastian Schöps

  Ausschreibung als PDF

• 2019

  Numerical Methods for the Solution of the Quasistatic Darwin Formulation

  Studienarbeit, Bachelorarbeit, Masterarbeit

  For the simulation of electromagnetic fields in many situations, quasistatic approximations to Maxwell’s equations are sufficient. The most well-known approximations are magneto-quasistatics (MQS) and electro-quasistatics (EQS). However, there is another formulation due to Darwin [1] which essentially combines MQS and EQS and allows to predict the behavior of problems as shown in Fig. 1. The Darwin formulation is less explored from the view point of computational engineering and thus many questions can be addressed within a thesis project. weiter

  Betreuer/innen: Prof. Dr. rer. nat. Sebastian Schöps, Idoia Cortes Garcia, M.Sc.

  Ausschreibung als PDF

• 2019

  Fast Adaptive Frequency Sweep for the Calculation of Scattering Parameters in the Frequency Domain

  Studienarbeit, Bachelorarbeit, Masterarbeit

  The Finite element method (FEM) in the frequency domain is one of the most powerful methods for the solution of high frequency electromagnetic field problems for resonators, filters, attenuators,etc. In many practical applications, however, the frequency response of the system over a broad frequency band is required.Fast Frequency Sweeping (FFS) is a class of methods used for the estimation of broadband S-parameters based on evaluation of a minimum amount of frequency points. Modern FFS methods include Reduced Basis Methods, Thiele based interpolation, Asymptotic Waveform Evaluation and Vector Fitting. Each of the methods have advantages and disadvantages depending on the specific characteristics of the frequency response of the system. weiter

  Betreuer/innen: PD Dr. rer. nat. Erion Gjonaj, Prof. Dr. rer. nat. Sebastian Schöps

  Ausschreibung als PDF

• 2019

  Finite Element Tearing and Interconnect for Maxwell’s equations using IGA

  Studienarbeit, Bachelorarbeit, Masterarbeit

  Isogeometric analysis (IGA) is a finite element method (FEM) using splines for geometry description and basis functions such that the geometry can be exactly represented. Recently, an isogeometric mortar coupling [1] for electromagnetic problems was proposed. It is particularly well suited for the eigenfrequency prediction of superconducting accelerator cavities. Each cell, see Fig. 1, can be represented by a different subdomain but may still share the same discretization. The approach leads to a (stable and spectral correct) saddle-point problem. However, its numerical solution is cumbersome and iterative substructuring methods become attractive. The resulting system is available from a Matlab/Octave code. In this project the finite element tearing and interconnect method (FETI) shall be investigated and standard, possibly low-rank,preconditioners implemented and weiter

  Betreuer/in: Prof. Dr. rer. nat. Sebastian Schöps

  Ausschreibung als PDF

• 2019

  Efficient simulation of power converters using multirate partial differential equations

  Multiscale and multirate problems occur naturally in many applications from electrical engineering, e.g. buck converters. An efficient simulation can be achieved using the concept of Multirate Partial Differential Equations. weiter

  Betreuer/innen: Andreas Pels, M.Sc., Prof. Dr. rer. nat. Sebastian Schöps

  Ausschreibung als PDF

• 2019

  Simulation of Electromigration Efffects in Electronic Devices

  Bachelorarbeit, Masterarbeit

  In electronics, the most serious failure mechanism is due to electromigrationin the interconnects. This effect shall be modelled and simulated within an existing software environment. weiter

  Betreuer/innen: Thorben Casper, M.Sc., Prof. Dr. rer. nat. Sebastian Schöps

  Ausschreibung als PDF

• 2019

  Adjoint-based Adaptivity for Uncertain HF Problems

  Studienarbeit, Masterarbeit

  The focus of this work is the adaptive construction of the polynomial surrogate modelin order to mitigate the curse-of-dimensionality. The efficiency of this approach shall be further improved by employing adjoint-based error measures. weiter

  Betreuer/innen: Niklas Georg, M.Sc., Prof. Dr. rer. nat. Sebastian Schöps

  Ausschreibung als PDF