Výpočetní tomografie je nástroj pro nedestruktivní inspekci vzorků, který je běžně používán v mnoha oblastech průmyslu a výzkumu. Některé tomografické přístroje umožňují snímání obrazů s prostorovým rozlišením pod jeden mikrometr. Zorné pole takovýchto přístrojů bývá malé, v rozsahu jednotek milimetrů či méně. Tím jsou omezeny rozměry vzorků, což je značně limitující. Toto omezení lze překonat pomocí různých technik pro rozšíření zorného pole. Jedna takováto dříve publikovaná metoda byla v této práci upravena a implementována pro přístroj Rigaku Nano3DX. Tato technika téměř zdvojnásobuje zorné pole přístroje bez nutnosti většího detektoru. Implementovaný přístup byl testován pomocí umělých i skutečných dat, a jeho účinnost byla zhodnocena subjektivně i objektivně, pomocí vizuální kontroly a metrik kvality obrazu. Hodnocení je převážně založeno na srovnání obrazů rekonstruovaných pomocí této metody s obrazy získanými pomocí většího detektoru. Implementovaná technika rozšíření zorného pole poskytuje věrné rekonstrukce vzorku, srovnatelné se zmíněnými protějšky.

Point set registration is a well-researched yet still not a very exploited area in computer vision. As the field of machine learning grows, the possibilities of application expand. This thesis investigates the possibility to expand an already implemented probabilistic machine learning approach to point set registration to more complex, larger datasets gathered in a forest environment. The system used as a starting point was created by Järemo Lawin et. al. [10]. The aim of the thesis was to investigate the possibility to register the forest data with the existing system, without ground-truth poses, with different optimizers, and to implement a SLAM pipeline. Also, older methods were used as a benchmark for evaluation, more specifically iterative closest point(ICP) and fast global registration(FGR).To enable the gathered data to be processed by the registration algorithms, preprocessing was required. Transforming the data points from the coordinate system of the sensor to world relative coordinates via LiDAR base coordinates. Subsequently, the registration was performed with different approaches. Both the KITTI odometry dataset, which RLLReg originally was evaluated with[10], and the gathered forest data were used. Data augmentation was utilized to enable ground-truth-independent training and to increase diversity in the data. In addition, the registration results were used to create a SLAM-pipeline, enabling mapping and localization in the scanned areas. The results showed great potential for using RLLReg to register forest scenes compared to other, older, approaches. Especially, the lack of ground-truth was manageable using data augmentation to create training data. Moreover, there was no evidence that AdaBound improves the system when replacing the Adam-optimizer. Finally, forest models with sensor paths plotted were generated with decent results. However, a potential for post-processing with further refinement is possible. Nevertheless, the possibility of point set registration and LiDAR-SLAM using machine learning has been confirmed.

This thesis is focusing on the construction of a four-stroke internal combustion engine for a 250 ccm road bike. Since it is a road bike, the introduction of legislation of the Czech Republic for this category is outlined in the introduction of the thesis. Furthermore, disassembling of similar and competitive engine was conducted. The thesis also describes the process of construction of this four-stroke internal combustion engine. In addition, the thesis compares friction loss on the main bearing crankshaft. In the latter part there is summarization of all findings.

The thesis is divided into three main parts. The first section summarizes the theory of the issue. Here we are unified theoretical information about the various possibilities of different approaches. The result of this part is therefore a general summary of theoretical possible procedures of creation bone implant, where each are listed the advantages and disadvantages. The theoretical part also contains information that ultimately, in practice, the author did not use. But his idea was to create a comprehensive look at the issue from several angles. The second part uses theoretical knowledge from the previous set of information as a basis for defining the steps required to successfully manage the issues of bone 3D printing. The third part will follow the guidelines of both previous and focuses on practical making bones and subsequent evaluation method chosen. There are discussed various steps that led to the final conclusion, making bones and work is then focused on the evaluation of the success of selected procedures and recommendations for future action.

A big concern when painting surfaces is the unevenness of the surface texture that is created by the paint. This is a well known problem for the automotive industry, referred to as The Orange Peel Effect, creating a surface texture like that of an orange. This project aims to answer if the currently used Wave Scan could be replaced with the new Optimap to measure the Orange Peel Effect. A standardized measurement of this Orange Peel Effect are the N1 and N3 values, calculated through the BMW-Ford-scale and used by Volvo Trucks. In the first part of this report five models are created and evaluated to make the measurements from the new Optimap comparable with the currently used Wave Scan. In this report it is shown that N1 and N3 could be estimated such that hat(N1) = 2, 551813 + 0, 018900 ∗ Tb + 0, 089610 ∗ Td hat(N3) = 3, 862056 − 0, 014959 ∗ Tb + 0, 019958 ∗ Tc + 0, 067837 ∗ Td where Tb,Tc and Td are measurements from Optimap. By replacing Wave Scan with Optimap Volvo Trucks would be able to measure underlying layers like the matte base coat. Volvo suspects that the underlying layers could affect the top coats surface structure. If this is true it could then be further investigated and in turn optimized. This first part is modelled using measurements from plates which are painted with the truck cabs. These plates are measured with both tools and 110 paired measurements are used for the modelling. The variance is analyzed using another set of 24 plates with 6 replicates each, yielding 144 paired masurements. The two tools measures significantly differently for different wave lengths. Some of Optimaps measurements are also significantly different between the replicates of the same plate. The second part of this project is to evaluate the effect that the base coat has on the end product surface structure. Volvo Trucks is interested in the trends over time in the orange peel. This is done using data acquired from the production line, with truck cabs measured with base coat applied and cabs with top coat applied. Does the base coat follow the same trends? The result is that, due to lack of paired data, not enough evidence is found to either support nor reject the hypothesis that the base coat affects the end products surface texture. A significant difference between the different base coats is found. This is discussed and taken into account in the third part. The third part consists of a recommendation to Volvo Trucks on how to use the Optimap and further investigate the possible predictors of orange peel. This recommendation mainly focuses on reducing the number of variables. This could be done with only one type of top coat painted on the different base coats, using the same type of base surface for every measurement. The surface could then be measured before and after the top coat is applied to aquire paired data. This could be done in a laboratory in small-scale, and depending on the outcome more experiments could be constructed. In future studies one can investigate one of the base coats further. The same experiment could then be done with different alternations of one base coat instead of using several.

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The incompressible fluid flow around the geometries of cerebral artery aneurysms is studied in this thesis. The aneurysm is a local extension of a vessel. This disease is dangerous only in the case of rupture. Then the blood is released into the brain. The need of accurate computation of the velocity and pressure fields in this geometries is motivated exactly by the question which aneurysm has tendency to rupture. The finite element method (FEM) is used for the computation of the flow. A good domain discretization is one of the main step in FEM. Modern computed tomography is able to produce series of the two- dimensional images and it is necessary to create an appropriate three-dimensional model of the tissue. This thesis includes the description of the mesh generation and the ways to smooth and improve the meshes. In the theoretical part the equations of fluid flow are formulated. A suitability of a choice of boundary conditions is discussed. Weak formulation for the equations and its discretization are presented. In the practical part velocity and pressure fields are computed by the various finite elements. Wall shear stress which plays an important role in the evolution of an aneurysm is also computed on the introduced meshes. Comparison of mesh smoothing filters, used finite elements and used...

Eye tracking is commonly used in many scientific fields (experimental psychology, neuroscience, behavioral economics, etc.) and can provide us with rigorous data about current allocation of attention. Due to the complexity of data processing and missing methodology, experimental designs are often limited to static stimuli; eye tracking data is analyzed only with respect to basic types of eye movements - fixation and saccades. In dynamic tasks (e.g. with dynamic stimuli, such as showing movies or Multiple Object Tracking task), another type of eye movement is commonly present: smooth pursuit. Importantly, eye tracking data from dynamic tasks is often represented as raw data samples. It requires a different approach to analyze the data, and there are a lot of methodological gaps in analytical tools. This thesis is divided into three parts. In the first part, we gave an overview of current methods for analyzing scan patterns, followed by four simulations, in which we systematically distort scan patterns and measure the similarity using several commonly used metrics. In the second part, we presented the current approaches to statistical testing of differences between groups of scan patterns. We present two novel strategies for analyzing statistically significant differences between groups of scan patterns and...

Testing is necessary factor to guarantee that ICs operate according to specifications before being delivered to customers. Testing is a process used to identify ICs containing imperfections or manufacturing defects that may cause failures. Inaccuracy and imperfections can be introduced during the fabrication of the chips due to the complex mechanical and chemical steps required during the manufacturing processes. The testing process step applies test patterns to circuits and analyzes their responses. This work focuses on VLSI circuit testing with two implementations for DFT (Design for testability); the first is an ATPG tool for sequential circuits and the second is a BIT (Built in Test) circuit for high frequency signal classification.There has been a massive increase in the number of transistors integrated in a chip, and the complexity of the circuit is increasing along with it. This growth has become a bottleneck for the test developers. The proposed ATPG tool was designed for testing sequential circuits. Scan Chains in Design For Testability (DFT) gained more prominence due to the increase in the complexity of the modern circuits. As the test time increases along with the number of memory elements in the circuit, new and improved methods are needed. Even though scan chains implementation effectively increases observability and controllability, a big portion of the time is wasted while shifting in and shifting out the test patterns through the scan chain. Additionally, the modern applications require operating speed at higher frequencies and there is a growing demand in testing equipment capable to test CMOS circuits utilized in high frequency applications.With the modern applications requiring operating speed at higher frequencies, there is a growing demand in testing equipment capable to test CMOS circuits utilized in high frequency applications. Two main problems have been associated when using external test equipment to test high frequency circuits; the effect of the resistance and capacitance of the probe on the performance of the circuit under test which leads to a faulty evaluation; and the cost of a dedicated high frequency tester. To solve these problems innovative test techniques are needed such as Built In Test (BIT) where self-evaluation takes place with a small area overhead and reduced requirements for external equipment. In the proposed methodology a Built In Test (BIT) detection circuit provides an efficient way to transform the high frequency response of the circuit under test into a DC signal.This work is focused in two major fields. The first topic is on VLSI circuit testing with two implementations for DFT (Design for testability); the first is an ATPG tool for sequential circuits and the second is a BIT (Built in Test) circuit for high frequency signal classification as explained. The second topic is focused on efficient implementations of arithmetic operations in arbitrary long numbers with emphasis to addition. Arbitrary-Precision arithmetic refers to a set of data structures and algorithms which allows to process much greater numbers that exceed the standard data types. . An application example where arbitrary long numbers are widely used is cryptography, because longer numbers offer higher encryption security. Modern systems typically employ up to 64-bit registers, way less than what an arbitrary number requires, while conventional algorithms do not exploit hardware characteristics as well. Mathematical models such as weather prediction and experimental mathematics require high precision calculations that exceed the precision found in most Arithmetic Logic Units (ALU). In this work, we propose a new scalable algorithm to add arbitrary long numbers. The algorithm performs bitwise logic operations rather than arithmetic on 64-bit registers. We propose two approaches of the same algorithm that utilize the same basic function created according to the rules of binary addition

The seeming lack of barriers to gene flow in the northwest Atlantic ocean has led to the general assumption that the population of the American lobster (Homarus americanus) is largely panmictic. However, morphological and genetic data presented in this dissertation suggest that lobster populations are less homogenous than once believed with potential for behavioral barriers to mating and selection of locally adaptive traits. Additionally, both long-term fishing pressures and the recent spread of a destructive epizootic shell disease may have impacted population structure. We developed a novel photographic technique to rapidly collect accurate morphological data with the ability to maintain a database of images for the purposes of re-sampling and testing additional hypotheses. During this study, we found significant morphometric differences between samples of lobsters from collection sites as close as 25km apart. Morphological differences may have originated due to differential selection or plastic responses to environmental variation. To analyze population genetic structure, I surveyed genetic variation using RADseq. Analysis of 1614 putatively neutral SNPs found little genetic difference (Average F¬ST=0.00137) between sample sites suggesting a high level of gene flow between regions. Several additional markers appeared to be under divergent selection between sample sites. A genome scan analysis of both neutral SNPs and SNPs under selection found several selected SNPs associated with principal components of morphological characters. A subsequent BLAST analysis identified a number of the selected SNPs lying in the H. americanus transcriptome, suggesting functional importance. Further experimentation is required to quantify the impacts of plasticity or local adaption in the origin of morphological differences between lobster populations, although the significant differences identified in this research are likely due to a combination of the two. The overarching conclusion is that lobster populations are, in fact, more differentiated than previously predicted and, as such, the findings presented here may have significant management implications.