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The theoretical part of dissertation is devoted to familiarization with the process of assembly and soldering of PCBs. There are described the selected types of lead-free solder paste, the various procedures of flux deposition, where the greater part is focuses to the printing through template. Also, I analyze the different procedures shouldering and soldering. I focused mainly on the mechanical mounting of SMD components soldering with help convection reflow and soldering in the vapor. In the practical part is described the design of the test PCB, methodology of assembly PCB and soldering various technologies with predefined settings. The analysis of the results is done by a non-destructive x-ray method and destructive micro-cut method. The x-ray method detects the position and size of the voids in the solder. This information is used for faster processing of micro-cut. The micro-cut method is included in the analysis for a more detailed examination of the solder joint. At the end of the thesis, there is a summary of the recommendation that the setting of the manufacturing process increases the quality of the brazed joint.

The methodology of visualization of soft tissue is in biology and medicine a topic for many years. During this period there were approving many techniques how to achieve accurate and authentic image of the researched object or structure. X-ray computed tomography is very helpful to get this goal but is necessary to improve contrasting techniques as well as the techniques of image post-processing. This thesis deals with imaging soft tissue. Specifically, it focuses on mouse liver contrasting with the artificial resin Microfil. Thesis also describes image processing technique (thresholding and region growing) for the data of the measurement with the goal of the visualization of the sample in 3D.

Additive technology (AT) is increasingly used to design unique parts, mainly due to the ability to produce complex structures such as lattice structures. However, this also includes the need to modify the process parameters or the production strategy of the AT, which is usually set to produce volume geometry. Using samples corresponding to the geometries of the lattice structures, the exact input values were measured, which were used to design the SLM (Selective laser melting) production process using a contour strategy. Thanks to this, vertical and angled (35.26°) struts with low porosity (up to 0.2 %), low surface roughness and high dimensional accuracy were produced. Porosity was measured on µCT, surface roughness and dimensional accuracy were measured on STL data. The results show that if the parameters of the SLM process are set correctly, it is possible to produce struts with low porosity and surface roughness using different combinations of laser power and scanning speed. The above findings were used in the creation of script that allow the selection of suitable process parameters to produce lattice structures.

The thesis presents computational simulation of compression test of a nickel foam and the 3D reconstruction of micro-CT images was utilized to generate the foam’s model of geometry. Explicit FEM is used to simulate compression test using software tool LS-DYNA and the stress–deformation curve is obtained together with deformed model’s mesh used for subsequent analysis. Sensitivity analyses were performed to configure the model and ensure best fit with values obtained during real-life experiment. The ANSYS Classic environment was then used to simulate tensile test of the foam compressed to various thicknesses. The tensile moduli in three mutually perpendicular directions of nickel foam were computed and the results were compared to experimental values as well. The results of tensile test simulation revealed considerable anisotropy of the foam’s elastic behavior. It can be said that the measured experimental data correspond very well with the elastic properties obtained from simulation up to certain level of compression. Analysis of the relationship between the element size and tensile moduli showed a significant difference between fine and coarse mesh. The optimal level of discretization and the overall model configuration ensuring high level of accuracy is proposed in this thesis.

The work is focused on research and development of a suitable method for creating a selective emitter for the visible and near infrared region so that they are able to work optimally together with silicon photovoltaic cells in a thermophotovoltaic system. The aim of the work was to develop a new method of creating very fine structures outside the current standard, which will increase the emissivity of the base material to meet the needs of a selective emitter for the VID and NIR region. The methods available to us for the creation of structures were chosen, from which we eliminated all unsuitable ones and we introduced the optimal procedure and parameters for their creation for the selected method. In this work, we focused on both ceramic and metallic materials, whose heat resistance and selective properties are key to this work. Part of the development of the emitter structures was also the need for pretreatment of the substrate itself, where great emphasis was placed on the purity of materials and surface roughness. Since ceramic materials cannot achieve a surface roughness so low that the desired structures can be formed, these materials have been purposefully used primarily for the purpose of combining the base material with thin layers of other high temperature material. Their compatibility and suitability were verified in terms of adhesion and subsequent heat resistance. The main material for the formation of fine structures was purposefully chosen tungsten, for which we verified the influence of the formed structure on the emissivity as well as the thermal stability during long-term exposure to high temperatures. The work thus represents not only a new method of creating very fine structures, which are not normally formed in such subtlety, but also opens the way to new possibilities of combining more materials to achieve the required selectivity of the thermophotovoltaic emitter.

This thesis concerns with design of micro sources and their implementation in Micro grid system. In the first part the work is aimed at definition of smart - grid, where describes their advantages, disadvantages and necessary changes, which has to be made in current distribution network for implementation this system. Further on the thesis concerns with detailed description of Micro grid, configuration of this kind of network, the issues in implementation and possibilities to provide ancillary services. The work also describes marginally virtual power plants, presents definition, components and types of virtual power plants. The final chapter describes the creation of micro sources in System modeler and subsequent testing of consumption cover to operate in island mode.

This semestral thesis focuses on the description of specific renewable resources in the form of thermophotovoltaic cells using selective radiators with micro/nano structures. This work deals with an introduction of renewable resources and specifically focuses on thermophotovoltaic. Thesis describes basic principles, but also influences affecting the proper functioning of these systems. It also focuses on selective radiators, which are created by mikro/nano structures, and factors that can affect their implementation or simulation. Part of the work are also examples of calculations of basic parameters of the structures, which will be used in the simulations. Next chapters are dealing with simulations which are analyzing thermal effects on termophotovoltaic system. Except the analysis itself there is also partial optimalization solving some of the negative thermal effects.

The aim of this semestral thesis is to compare the possibilities of available micro-CT systems. Theoretic part of this thesis there deals with possibilities of staining soft tissues and embryos because of enhancement the contrast of micro-CT images. Here follows a description of sources X-ray and detectors of available micro-CT systems. In practice there was realized the staining of embryo in cooperation with Department of histology and embryology in Brno. Then followed a measuring on FSI in Brno, ČVUT in Prague and synchrotron Elettra in Italy. In semestral thesis are described of the thesis there are compared the micro-CT systems and results of measuring embryos by means of presented systems and results are compared.The best results were obtained on micro-CT in Brno, where X-ray tube and flat panel detector were used. This images were used for a segmentation of cartilage olfactory system by means of 3D region growing. From results they were created 3D models for comparison with a manually segmented model. A less accurate results were obtain with the semi-automatic segmentation but this method isn’t too time-consuming.

The dissertation thesis is focused on research and development of modern emission MEMS sensors. The emission sensor based on the field emission from nanostructured materials represents innovative approach to pressure sensing. The nanostructures serve as electron emitter in an electric field between the cathode and anode in the pressure sensor. This electric field is constant and the change in ambient pressure causes the change of distance between electrodes, thereby the electric field is increasing. This intensity is proportional to the emission from the cathode made of nanostructured material. Changing the distance between the electrodes is caused by the deflection of the deformation element - the membrane, which operates the measured pressure. In the current state of the art an extensive research is carried out to find new nanostructured materials with good emission properties. Four nanostructured materials have been chosen and then experimentally prepared and characterized inside the vacuum chamber. For the simulation of diaphragm bending, the chamber is equipped with linear nano-motion drive SmarAct that enables precise changes of the distance between two electrodes inside the vacuum chamber. The computer model to predict the deformation of diaphragm was prepared in the simulation program CoventorWare. The behavior of diaphragm in a wide range of dimensions of the membrane, its thickness and the applied pressure are possible to predict. The dependencies of the current density on the electric field are plotted from the measured emission characteristics of nanostructured materials and thus characterized nanostructured materials can be compared. The dependencies are further converted by Fowler-Nordheimovy theory on the curve (ln(J/E2) vs. 1/E), whose advantage is linear shape. Basic parameters describing the emission properties of characterized nanostructured materials are deducted. Two methods for vacuum packaging of the sensor electrodes are designed. Anodic bonding technology and encapsulating using glass frit bonding are tested. To evaluate the bonding strength, the bonded substrates are tested for tensile strength.