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This diploma thesis is focused on description of the properties of a layer of Inconel 718 applied on austenitic steel AISI 304 by the Cold Spray and subsequently remelted by electron beam. The first part presents the Cold Spray with its properties, advantages and disadvantages, and also describes the principle of electron beam remelting and other possible uses of electron beam, for example welding, drilling, heat treatment etc. The second part describes the material and the methods used for the preparation and evaluation of the samples. There are evaluated the porosity, microstructure and microhardness of the layers applied by the Cold Spray and these properties are further compared with the properties of the same layers remelted by electron beam. In conclusion, the results of the porosity of the layers applied by the Cold Spray are discussed with the literature and the results of electron beam remelting are only partially described here, because it was not possible to find literature about this topic. There are also suggestions for further research of the properties of this layers, which is necessary to know before implementing this method of producing layers for commercial production.

The use of micro- and nanotechnologies is necessary in the development of advanced sensor systems. In this thesis few selected technologies were studied and tested on fabrication of creating two different systems for bioelectrical and electrochemical applications. For biolelectrical applications a chip with a pair of gold nanoelectrodes was designed and implemented. For electrochemical analysis a novel two electrode system was designed and realized, which should contribute by greater sensitivity and accuracy in amperometric detection compared with three-electrode systems in voltammetric analysis. The fabricated systems were tested and the results were discussed.

This diploma thesis treats about technology of laser and its use in practice. It describes principle, available types and possible applications in material working. The work is specifically focused on the technology of laser cutting. Diploma thesis was written in co-operation with Technologické centrum a. s. company. This company disposes of four cutting lasers. The aluminium template was produced by laser Byspeed 5200 ARC.

Skyrmion is a topologically protected nanometer-sized spin configuration, which makes it a promising candidate for future memory devices. All skyrmion applications are based on the formation and manipulation of spin textures in nanostructured elements. Therefore, fabrication of geometrically confined skyrmion-based nanodevices is an essential step in the investigation of skyrmion properties. In this study, my research mainly focuses on the fabrication of high-quality Fe3Sn2 nanostripes with different geometric parameters for Lorentz transmission electron microscopy (LTEM) by a focused ion beam (FIB) system. The observation of the skyrmions using LTEM was mainly performed by Dr. Qiang Zhang, although I have deeply involved the discussion on new samples to be fabricated based on the results obtained from LTEM and also performed some LTEM experiments. To investigate the formation process and thermal stability of skyrmions in a geometrically confined environment, I have fabricated more than fifty high-quality nanostripes with a width of 265-4,000 nm. Studying with LTEM, a distinct evolutionary path of stripe-skyrmion transformation is observed after gradually increasing the magnetic field (out-of-plane direction) and the critical magnetic field of skyrmion is found to decrease with an increasing strength of confinements. Moreover, a series of racetrack devices with controlled thicknesses (125-404 nm) is fabricated to study the effect of thickness in skyrmion formation. Overall, in order to obtain less damaged, flat skyrmion-based devices by FIB system, experimental parameters are optimized and fabrication skills are improved. This method develops the possible application of centrosymmetric frustrated magnet Fe3Sn2 in skyrmion-based racetrack devices.

The study examines the Projection method and the simultaneousapproximation-term (SAT) method as boundary treatment for the dynamic beam equation using summation-by-parts (SBP) operators for handling the inner domain. The methods are examined for both the homogeneous constant coefficient case, and the inhomogeneous piecewise constant coefficient case with a coupled interface. The outer boundaries are handled by SAT or Projection, the coupled interfaced is handled by Projection or a mix between Projection and SAT. Solutions are integrated in time with finite central difference schemes and compared to analytical solutions. A convergence study is conducted with respect to the spatial discretization to measure the accuracy, and the stability is examined by numerical simulations of the CFL-condition. The study shows that Projection has the same accuracy as SAT for most boundary conditions while allowing for a larger timestep. A discontinuity in the medium is found to be handled equally accurate by Projection and the Projection and SAT mixture for all but one case studied, where the mixture was slightly more accurate.

The purpose of this study is to analyze the foundation beam linked between two shear walls in the presence of lateral loads. Mat foundation with shear walls is one of the most commonly used reinforced concrete structural systems to resist the lateral load. When two independent walls are connected with a link beam, also known as the coupling beam, the overturning resistance of the building is largely increased. However, the coupling beams are relatively weaker structures and can develop larger stresses. When there is a mat foundation, or pile cap in case of pile foundation, the part of the foundation which is right below the coupling beam where no shear wall is present, will also get large stresses due to the highly rigid nature of adjacent shear walls. Most of the lateral deformations are imposed only on the coupling beams and foundation beam. There is not much literature or design procedure found in books and codes to mitigate the high risks associated with the foundation beam between shear walls on its design vulnerability. This thesis is focused on the risks associated with exceptionally high forces on the foundation beam due to earthquake forces.

Two novel plasma sources (one neutral source and one pulsed inductively coupled plasma source) and ashing process characterization were investigated. The primary goal was to characterize these source properties and develop corresponding applications. The study includes process damage assessment with these two sources and another continuous wave (13.56MHz) plasma source. A global average simulation of the pulsed discharges was also included.;The transient plasma density and electron temperature from the double probe analysis were compared with single Langmuir probe results with sheath displacement corrections in pulsed discharges (200Hz--10kHz). The equivalent resistance method can be used effectively to analyze these double probe data. The transient behaviors of the plasma density and electron temperature are in accord with the model of the discharge. The hyper-thermal neutral source based on the surface reflection neutralization techniques was shown to provide enough fast neutrals for ashing applications. The surface roughness of the post-cleaned wafer was less than 10A. Ex-situ and in-situ measurements yield typical removal rates of about 10 A/s without stream collimation. The removal rates at increasing pressures show a trade-off between creating higher density plasma, leading to a large initial neutral flux and attenuation of neutrals due to collisions. Changing the reflector plate changes the neutral energy without changing the discharge composition. A novel technique, combining momentum and heat flux measurements shows that neutral stream energy is 3--6 eV and the neutral flux is on the order of 1015 cm-2 s-1. The derived etch rates from the measured neutral flux and energy values and the experimental rates are in good agreement. Quasi-static capacitance-voltage measurements demonstrate that the low energy neutral source induces much less damage than other plasma sources. Most of the neutral process damage is caused by uv photons escaping from the plasma source zone. The process-induced damage vary with the reflector bias and rf power.

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