The goal of this thesis is to create a literature search about a rotating electrical machine with switching of magnetic flux, to explain its construction concept and its operating behavior, to create an initial concept of generator, calculate chosen construction with finite element method analysis and to compare analysis results with analytical design. To create a concept of the generator one of available designing procedures will be used.

Rising demand for high productivity of machine tools leads to increase of the dynamics of the machine tool. With higher dynamics of the components is produced a free tool vibr ation that can affect the path accuracy of the feed axis and of the tool. In this thesis are examined various parameters of the feed axis, so that the influence of each parameter could be determined. To determine these factors is in this thesis created a structuralmechanical model of the feed axis by means of the finite element method and this thesis presents a connection of the FE model with a control loop of an axis that allows the theoretical study of the influences on the accuracy of the feed axis. The results show succes sful coupling of the FE model with the control loop. Selected parameters are analyzed in this paper.

In this thesis, the different solution methods for saddle-point systems aris- ing from fluid dynamics are studied. The main emphasis is on Krylov subspace methods with effective preconditioning techniques for saddle-point systems ob- tained from finite element discretization of the Navier-Stokes equations. Two preconditioning techniques are presented: pressure-convection-diffusion precon- ditioning (PCD) and least-square commutator preconditioning (LSC). Both pre- conditioners are validated on two benchmarks: lid-driven cavity and flow around cylinder. From the computational point of view, we focus on comparing the performance of used solvers, with emphasis on our implementation of PCD pre- conditioning. All numerical simulations are performed by software Firedrake. 1

One of the most common concern among patients who need orthodontic treatment is treatment duration. The ability to accelerate orthodontic tooth movements would be beneficial to reduce the undesired side-effects of prolonged treatment. Methods have been used in conjugate with common orthodontic appliances to shorten the treatment. One of them is to use vibrational force (VF), which is non-invasive. The VF stimulates bone modeling and remodeling, which is essential to tooth movement. However, commercial devices used in the clinic failed to deliver consistent outcomes. The effects of the VF highly depend on its intensity the tooth receives. There must be a range of stimulation that optimizes the effects. The stimulation outside the range either have no effects or creates damages, which adversely affects the orthodontic treatment. Since these devices have generic mouthpiece and teeth are in different heights, hence some teeth cannot get force stimulation and others may be overloaded. The current designs also do not have ability to adjust the level of VF intensity that individual tooth needs, as in some cases orthodontists are required to move a tooth faster than others or even slower, which needs the device to be personalized. Therefore, the primary cause of inconsistent clinical outcomes is the inadequate design of the mouthpiece of the current device. The goal of this study is to design a better vibratory device that not only guarantees VF delivery but also enables orthodontists to control the level of VF on the individual tooth, which meets the patient’s treatment needs. This is a preliminary study to understand the effects of different design parameters affecting the VF distribution on teeth. A finite element model, which consists of human upper and lower jaws in their occlusal positions and a mouthpiece, xii was created. The VF was from a vibratory source with a peak load of 0.3N and specified frequencies (30 and 120 Hz). The element size was determined through a convergence test and the model was validated experimentally. Results showed that the VF distribution among the teeth relies on the material property of the mouthpiece. The distribution is uneven, meaning some teeth bearing much more load than others. This means, with the current device design, teeth

Kommunikation och tillgänglighet som mål Mitt program består av fem hus,630 kv var,studentsbostäder 541 kv och ett kontors komplex,komplexet är i samma byggnad som t-bana hus. Alla hus är på parken, på grund av ljusförhållande,eftersom programmet är orienterad mot söder.För att komma till bostäder går man genom trappor,det finns fem nya trappor från gatan till bostäderna som har som funktion,förutom att nå bostäder,att göra möjligt till alla grannar att gå till parken från gatan själv.Programmet har också för mål att skapa ett mera dynamiskt urban liv med sitt multifunktionella grannskap,väl dimensionerad hus och anslutna ytor,varierande boende av alla åldrar,och utveckla ett mera aktiv förhållande till parken och med de nya bosättare

Formulations for analysis of printed antenna structures are derived and compared, to determine one to implemented in SuperNEC based on the efficiency of its numerical solution in terms of memory usage and solution time. SuperNEC is a software application for computing the response of electromagnetic structures to electromagnetic fields. SuperNEC cannot be used for simulation of printed antenna structures. This is because the formulation that is implemented in SuperNEC does not account for the effect of the substrates that the radiating elements of the antenna structure are printed on, and it is also not intended for antenna structures whose radiating elements are surfaces. Two MoM (Method of Moments) formulations and a FEM (Finite Element Method)-MoM formulation are presented, together with different models for the antenna feed. The FEM-MoM formulation is selected for implementation in SuperNEC because it is argued that it is likely to be more memory efficient when compared to the MoM formulations, and also that less time is required to fill the matrices resulting from the numerical solution of the formulation. The formulation is implemented in a stand alone software application, which will be integrated into SuperNEC. Numerical results that are computed using the software application are presented to illustrate correct implementation of the formulation. The results are compared to: an exact solution, results from another publication, and results computed using a different formulation. Good agreement is obtained in each case.

Syftet med denna studie var att få vetskap om hur lärare använder sig av Favoritmatematik i undervisningen för att främja elevernas kunskaper i de femförmågorna. Syftet var även att få en uppfattning om hur läraren förhåller sig tillundervisningen om läromedlet inte räcker till. Vi valde att utföra kvalitativaintervjuer via zoom med F-3 lärare. Urvalet består av sex erfarna lärare som hararbetet med matematikundervisning i lågstadiet i minst 4 år. I vårt resultatframkommer det att lärarna använder sig av läromedlet i stor utsträckning menatt de behöver komplettera detta med övningar och extra material.

Partial differential equations on domains presenting point singularities have always been of interest for applied mathematicians; this interest stems from the difficulty to prove regularity results for non-smooth domains, which has important consequences in the numerical solution of partial differential equations. In my thesis I address those consequences in the case of conforming and penalty finite element methods. The main results here contained concerns a priori error estimates for conforming and penalty finite element methods with respect to the energy norm, the $\mathcal{L}^2(\Omega)$ norm in both the standard and weighted setting.

The double angle connection (sometimes referred to as a cleat connection) is one of the most commonly used simple shear connections, and many investigations have been conducted on this type of connection. However, most of these investigations have focused on either the strength or the moment-rotation relationship under shear loading. Several investigations have recently been performed on the behavior of double angle connections subjected to shear plus axial tensile loads. In these investigations, analytical models and design formulas have been proposed to model the complex behavior of these connections when subjected to the combined loading. However, a complete design model has not been developed. To fulfill the need for a design procedure, double angle connections were studied for three different loading cases. The first case was used to establish the load-displacement relationship under axial tensile loads. The second case was to establish the moment-rotation relationship under shear loads. Finally, the third case was to find the effects of combined axial tensile loads and shear loads on the behavior of double angle connections. For these purposes, 3D-nonlinear finite element models were developed to simulate the connection behavior under the three loading cases. The commercial software package, ABAQUS, was used for the study. The complex phenomena of contact problems and the pretension forces in the bolts were simulated. A simplified angle model and an equivalent spring model were developed from the 3D results. / Ph. D.

Diese Arbeit beschäftigt sich mit der Untersuchung der Wabenstruktur eines thermoplastischen Sandwichmaterials anhand von Daten, die durch das Verfahren der Computertomographie gewonnen wurden. Diese Untersuchung dient zur Modellierung eines repräsentativen Volumenelementes, welches die Zellgeometrie des Wabenkerns möglichst genau wiedergibt. Das Ziel dieses Vorgehens ist die Bestimmung effektiver Materialkennwerte, die zur mechanischen Simulation nach der Methode der finiten Elemente angewendet werden können.:1. Einleitung 2. Grundlagen 2.1 Sandwichbauweise 2.1.1 Biegeverhalten von Sandwichmaterialien 2.1.2 Spannungen in den Schichten 2.2 ThermHex-Waben als Kernmaterial 2.2.1 Material und Werkstoffkennwerte 2.2.2 Fertigung 2.2.3 Definition der Wabengeometrie 2.3 Mechanisches Verhalten von Wabenkernen im elastischen Bereich 2.4 Möglichkeiten zur Bestimmung von Elastizitätstensoren 2.4.1 Analytische Herangehensweise 2.4.2 Experimentelle Herangehensweise 2.4.3 Morphologische Herangehensweise mittels repräsentativen Volumenelement 3. Mikrostrukturelle Analyse 3.1 Untersuchungsobjekte 3.2 Untersuchungsmethodik 3.3 Untersuchungsergebnisse 3.3.1 Auswertungsproblematik 3.3.2 Zellweiten und Reihenabstände 3.3.3 Wandstärke 3.3.4 Zellwandlängen und -winkel 3.3.5 Zellwand- und Wölbungsradien 3.3.6 Kernhöhe und Schrägungswinkel des Wabenkerns mit Deckschichten 4. Modellierungsmethodik und -ergebnisse 4.1 Werkstoffabhängige und geometrische Parameter 4.2 Validierung der periodischen Randbedingungen 4.3 Validierung der Simulation mittels analytischer Herangehensweise 4.4 Geometrische Modellerstellung 4.5 Simulationsergebnisse der RVE-Grundtypen 5. Sensitivitätsanalyse 5.1 Komplexitätsvariation 5.2 Einfluss streuender Parameter 6. Simulierter 3-Punkt-Biegeversuch 7. Diskussion 7.1 Simulationsvalidierung 7.2 Verhalten der RVE-Grundtypen 7.3 Erkenntnisse der Sensitivitätsanalyse 7.3.1 Komplexitätsgrad 7.3.2 Modellsensitivität 7.4 Anwendungsfall der 3-Punkt-Biegung 8. Zusammenfassung und Ausblick 9. Literatur- und Quellenverzeichnis 10. Anhang