Le visage humain joue un rôle important dans la communication interpersonnelle. La dysfonction du visage ou le défigurement due aux traumatismes ou pathologies peuvent entraver les activités sociales normales. Le traitement chirurgical est souvent nécessaire. De nos jours, le résultat du traitement chirurgical et l’état d’établissement ne sont estimé qu’avec les méthodes qualitatives telles que l’observation visuelle et la palpation. Dans l’attente de fournir des critères quantitatifs, cette thèse a pour l’objectif de modéliser la mimique faciale utilisant MEF (Méthode d’Éléments Finis) sur la base des données d’IRM (Imagerie par Résonance Magnétique). Un modèle sujet-spécifique du visage a été construit sur la base de la segmentation des données IRM ; il contient des parties osseuses, muscles de la mimique (p.ex. le muscle grand zygomatique), les tissues mous sous-cutanées et la peau. L’identification des tissus mous biologiques a été réalisée via des essais de traction bi-axiale et la modélisation numérique. Ensuite, le modèle géométrique a été maillé pour effectuer des calculs EF simulant trois mouvements mimiques du visage (sourire, prononciation du son « Pou » et « O »). Les muscles ont été modélisés comme un matériau quasi-incompressible, transversalement isotrope et hyperélastique, avec la capacité d’activation. Des informations pertinentes (p.ex. l’amplitude de contraction du muscle) utilisées dans la simulation ont été extraites de la mesure des données d’IRM. Il est à noter que les mêmes données expérimentales d’IRM telles qu’ils ont utilisées dans la modélisation ont été prises comme une référence de validation pour les résultats de simulation. Cette étude peut être appliquée cliniquement dans l’évaluation du traitement faciale et le rétablissement postopérative. / Human face plays an important role interpersonal communication. Facial dysfunction or disfigurement due to trauma or pathologies may impede normal social activities. Surgical treatment is often necessary. Nowadays, treatment outcome and rehabilitation condition are estimated only by qualitative methods, such as visual observation and palpation. In expectation of providing quantitative criteria, this thesis proposes to model facial mimics using FEM (Finite Element Method) on the basis of MRI (Magnetic Resonance Imaging) data. A subject-specific face model was reconstructed based on segmentation of MRI data; it contains bony parts, mimic muscles (e.g. zygomaticus major muscle), subcutaneous soft tissues and skin. Identification of biological soft tissues was conducted through bi-axial tension tests and numerical modeling. Then the geometric model was meshed to conduct FE calculations simulating three facial mimic movements (smile, pronunciation of sound “Pou” and “O”). Muscle was modeled as quasi-incompressible, transversely-isotropic, hyperelastic material, with activation ability. Relevant information (e.g. contraction amplitude of muscle) used in simulation was extracted from measurement of MRI data. It is to be noted that the same experimental MRI data as used in modeling was taken as validation reference for simulation results. This study can be applied clinically in evaluation of facial treatment andpostoperative recovery.

A triangular B-spline (DMS-spline)-based finite element method (TBS-FEM) is proposed along with possible enrichment through discontinuous Galerkin, continuous-discontinuous Galerkin finite element (CDGFE) and stabilization techniques. The developed schemes are also numerically explored, to a limited extent, for weak discretizations of a few second order partial differential equations (PDEs) of interest in solid mechanics. The presently employed functional approximation has both affine invariance and convex hull properties. In contrast to the Lagrangian basis functions used with the conventional finite element method, basis functions derived through n-th order triangular B-splines possess (n ≥ 1) global continuity. This is usually not possible with standard finite element formulations. Thus, though constructed within a mesh-based framework, the basis functions are globally smooth (even across the element boundaries). Since these globally smooth basis functions are used in modeling response, one can expect a reduction in the number of elements in the discretization which in turn reduces number of degrees of freedom and consequently the computational cost. In the present work that aims at laying out the basic foundation of the method, we consider only linear triangular B-splines. The resulting formulation thus provides only a continuous approximation functions for the targeted variables. This leads to a straightforward implementation without a digression into the issue of knot selection, whose resolution is required for implementing the method with higher order triangular B-splines. Since we consider only n = 1, the formulation also makes use of the discontinuous Galerkin method that weakly enforces the continuity of first derivatives through stabilizing terms on the interior boundaries. Stabilization enhances the numerical stability without sacrificing accuracy by suitably changing the weak formulation. Weighted residual terms are added to the variational equation, which involve a mesh-dependent stabilization parameter. The advantage of the resulting scheme over a more traditional mixed approach and least square finite element is that the introduction of additional unknowns and related difficulties can be avoided. For assessing the numerical performance of the method, we consider Navier’s equations of elasticity, especially the case of nearly-incompressible elasticity (i.e. as the limit of volumetric locking approaches). Limited comparisons with results via finite element techniques based on constant-strain triangles help bring out the advantages of the proposed scheme to an extent.

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The diploma thesis deals with a mechanical and thermal analysis of 3-cylinder petrol engine piston with capacity of 1,2 l and maximal output 47 kW. The computation analysis was created with the use of finite element method in the Ansys application. The strain solution was created using several techniques. The 3D model was made according to a real piston in the Pro/Engineer and was partly simplified for computation. Crank mechanism forces and the load stresses were solved using Mathcad. Calculations are done for three positions of power cycle engine, where the maximal loads of the piston are expected. Last part of the thesis is calculation of safety factor highcyclical fatigue made using Femfat application.

The diploma thesis deals with design of structural system of selected parts of load-bearing structure of car park – common floor slab, selected columns, staircase. The Finite Element Method software is used to analyse the load-bearing structure, the results are verified by simlyfied hand-done calculation. The design of structures is done according to valid standards.

This thesis deals with the design of the protective frame protecting occupants in rollover (ROPS). The creation of the calculation model, in order to perform a stress-strain analysis of the frame under the conditions of the homologation test. Execution modal analysis with the inclusion of the mass of the auxiliary device. A motion for a protective frame is designed so that it can be subjected to destructive test according to standards ČSN EN ISO 3471. The strength and modal analysis was carried out using the finite element method (FEM). The diploma thesis was conducted in cooperation with the company, the Tatra Truck a.s.

This work deals with design of thermal source of panel shape for scientific biological application. Panel has adjustable surface temperature and thermal gradient. The first part of this work concern with design and numerical modeling of the thermal system, application of materials and arrangement of thermal and cooling devices – Peltier elements. Second part of this work is about construction of the panel and experimental measurement.

The theme of this master´s thesis is calculation and measurement of the parameters of induction motor. The thesis is divided into several parts. The first and the second part describes the general construction and operating principle of asynchronous motors. The construction includes a description of each part of induction motor, which consists of stator and rotor. The thesis deals with three-phase symmetrical and asymmetric single-phase motors. Principle of operation with using the rotating magnetic field, which is circular at three-phase motors, single phase motors have field elliptical shape. The next part contains the motor replacement scheme. The fourth part contains the calculation of motor´s parameters through the formulas. In this part the procedures for obtaining parameters of the replacement scheme of induction motor are defined. The process of calculating the parameters of the motor replacement scheme of threephase asynchronous motor is created according to given documentation is the next part for the certain type. The next content of the thesis describe finite element method, simulation and measurement of asynchronous motors to get of parameters from no-load and short-circuit test. The comparison of the results from measurement, analytical calculation and from simulation is given in the last chapter.

Aim of the diploma thesis is design elements of slope stabilization in accordance with the planned highway D3 in Slovakia section of Cadca, Bukov - Svrčinovec and relocation of a local road. Objective subject is situated on the slopes of Cadca. In diploma thesis is an analysis of the area with the proposed stabilizing elements in the 5 GEO FEM, their assessment, including determining the overall stability of the territory according to the degree of safety.

The diploma thesis deals with comparative analysis of stress and strain of notched machine parts using photoelasticity and finite element method (FEM). Experimental and numerical comparative analyses were performed on three models: hook, J shaped bracket and 3-point bending beam with notch. Equivalent stresses, principal stresses and its directions were analyzed. The emphasis is given on photoelasticity, the theory and principles of photoelasticity are described in more detail. FEM analysis was performed using software ANSYS 11. The work presented includes the preparation of polariscope in the laboratory of Institute of machine and industrial design in order to use it in tutorials focused on experimental stress analysis using photoelasticity.