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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Internetový výukový atlas zaměřený na půdní členovce / Internet Educational Atlas Focusing on Soil Arthropods

Dvořáková, Jana January 2013 (has links)
The main objective of this thesis was to create an educational website aimed at soil arthropods. It can be used primarily by teachers of biology and ecology, lecturers of extracurricular science education or by the students who are interested in this issue. This photographic atlas of soil arthropods consists of my own micro images obtained by the use of light and scanning electron microscope. The micro images are accompanied by text to each group of soil arthropods, which is divided into sections containing information about the systematic classification, anatomy and morphology, biology and importance, eventually representatives of the group. The atlas is accompanied by other materials usable in the classroom, such as didactic test, didactic game and proposals for group work, worksheet, field and laboratory work or educational presentations focused on soil arthropods. These materials can be downloaded from the website, along with the entire atlas of soil arthropods. The atlas is available on the following address: https://sites.google.com/site/pudniclenovci/. The review of the literature deals with the importance of arthropods in the soil and their mutual interactions. Then I describe the methods of study of arthropods (sampling, sample preparation for light and scanning electron microscopy and...
32

Biosurfaktanty a jejich využití pro inkorporaci hydrofobních domén do moderních nosičových systémů / Utilization of biosurfactants for incorporation of hydrophobic domains into modern controlled-release systems

Nešpor, Tomáš January 2021 (has links)
This work deals with the current topic of carrier systems. Since the biggest problem is the passage of hydrophobic drugs through the bloodstream, or through universal body barriers (eg blood-brain), it is necessary to chemically modify these carriers in order to be able to administer hydrophobic substances effectively. Based on a literature search, several systems are designed and subsequently studied, in which there is a presumption of possible use for carrier systems and at the same time they have biosurfactants incorporated in them due to their ability to solubilize hydrophobic molecules. The theoretical part of this work will describe the individual biosurfactants, the process of their production, their physicochemical properties, and the possibility of their use in carrier systems. At the same time, the individual carrier systems, the procedure of their preparation, the possibilities of their use are described, and their advantages and disadvantages are also compared. In the practical part, the screening of both individual substances and their mutual interactions, as well as methods used to study the emerging structures is then performed. The study of molecular interactions is primarily performed using the technique of dynamic light scattering. The next part describes the optimization of hydrogel formation with incorporated biosurfactants in their structure and then the formed gels are subjected to rheological and solubilization tests. The study of the internal structure of these gels is performed using a scanning electron microscope.
33

Testovací rozhraní integrovaných obvodů s malým počtem vývodů / A Test Interface for Integrated Circuits with the Small Number of Pins

Tománek, Jakub January 2017 (has links)
This study explores the possibilities for reducing the number of pins needed for scan mode interface. In the first part of this paper the existing solutions and methods that are usable for this purpose are described. Specific four pin, three pin, two pin, one pin and zero pin interfaces are designed in second part. Advantages and disadvantages of existing solutions and methods as well as designed and proposed interface are summarized in the conclusion.
34

Slepá Dekonvoluce Obrazu ve STEM Módu Elektronového Mikroskopu / Blind Image Deconvolution in STEM mode of Electron Microscope

Valterová, Eva January 2018 (has links)
Slepá dekonvoluce je metoda, při které je rozptylová funkce a skutečný obraz rekonstruován zároveň. Cílem této práce je představit různé metody slepé dekonvoluce a najít optimální metodu rekonstrukce původního obrazu a rozptylové funkce. Jako nejvhodnější metoda slepé dekonvoluce byl zvolen algoritmus střídavé minimalizace, který byl upraven a testován. Vlastnosti navrženého algoritmu byly testovány na uměle degradovaných datech a na reálných datech pořízených skenovacím transmisním elektronovým mikroskopem. Účinnost algoritmu byla hodnocena hned několika hodnotícími kritérii. Byla zjištěna omezení algoritmu a tím specifikováno jeho využití.
35

STUDY OF ENERGY ABSORPTION IN MICRO – STRUT LATTICE STRUCTURE PRODUCED BY SELECTIVE LASER MELTING / STUDY OF ENERGY ABSORPTION IN MICRO – STRUT LATTICE STRUCTURE PRODUCED BY SELECTIVE LASER MELTING

Vrána, Radek January 2019 (has links)
Předložená dizertační práce je součástí většího výzkumného projektu, který si klade za cíl využití mikro prutové konstrukce vyrobené technologií SLM jako absorbér rázové energie s přesně navrženými vlastnostmi. Hlavním cílem práce je vývoj numerického modelu deformačního chování mikro-prutové konstrukce vyrobeného technologií Selective Laser Melting (SLM) z materiálu AlSi10Mg. Aby bylo možné dosáhnout hlavního cíle dizertační práce, bylo nutné analyzovat vliv procesních parametrů technologie SLM na tvorbu vnitřních materiálových vad a drsnost povrchu při výrobě mikro-prutové konstrukce. Tyto imperfekce degradují její mechanické vlastnosti a jejich odstranění zlepší možnosti a přesnost numerické predikce. Výsledky ukazují významný vliv dvou hlavních parametrů – skenovací rychlosti laseru a výkonu laseru. Na základě těchto poznatků byly dále definovány parametry vstupní energie Ein a lineární energie Elin, které zahrnují oba zmíněné parametry a byly definovány jejich limitní hodnoty pro minimalizaci vzniklých imperfekcí. Deformační chování vyrobené mikro-prutové konstrukce bylo analyzováno na navrženém pádové zařízení, které umožňuje testování s dopadovou energií až 120 J. Deformační chování je vyhodnocováno s využitím obrazové analýzy záznamu vysoko rychlostní kamery a silového průběhu z tenzometru. Výsledky analýzy byly využity pro validaci numerického modelu v programu ANSYS Explicit, do kterého byly implementovány poznatky o reálném tvaru vyrobeného mikro-prutového materiálu ve formě eliptického modelu geometrie a informace o reálných mechanických vlastnostech ve formě vyvinutého materiálového modelu. Výsledné porovnání výsledků experimentu s predikcí numerického modelu ukazují dobrou shodu v místě maximálního zatížení Fmax (odchylka 5 %) i průběhu celé deformace vzorku. Tyto poznatky budou v budoucnu využity při návrhu absorbéru energie s definovanými mechanickými vlastnostmi.
36

Generace kovových nanočástic v nízkoteplotním plazmatu v kapalině / Generation of metallic nanoparticles by non-thermal plasma in liquids

Čechová, Ludmila January 2020 (has links)
This thesis focuses on the process of nanoparticle generation using new source of nonthermal plasma combining corona and pin-hole discharge in liquids. The theoretical part is focused on generation of metallic nanoparticles using various types of plasma discharge, the properties of metallic nanoparticles, their preparation by other methods and methods of characterization of nanoparticles. The experimental part deals with the preparation of copper, silver and gold nanoparticles from solutions of their precursors. The influence of experimental conditions, such as the influence of voltage polarity, effect of precursor concentration, effect of added electrolyte or reducing agent were investigated. All samples were analyzed by UV-VIS spectroscopy. Dynamic light scattering was used to determine the sice of nanoparticles. To confirm the presence of nanoparticles, samples were analyzed using scanning microscope with and energy dispersion spectrometer for elemental analysis.
37

Vliv velikosti částic kosmetických pigmentů na vlastnosti finálního výrobku / Influence of particle size of cosmetic pigments on final properties product

Obručová, Kateřina January 2020 (has links)
This diploma thesis is focused on the study of the influence of the of size cosmetics pigments on the properties of the final product. This effect was studied on samples of make-up given by industry partner. Make-up samples were measured by the rheology method and the yield stress of all samples was determined. Scanning electron microscopy was used to determine the size and shape of the pigment particles. Particle size was also measured by dynamic light scattering, but the results were influenced by forming aggregates. To easier determination of the types of pigments in the sample was determined elemental composition of the pigments (Ti, Fe, O, Al) by EDS detector. Due to the unknown composition of make-up, the information was supplemented by X-ray powder diffraction (XRD) analysis, and it was possible to determine the compounds TiO2 (anatase and rutile), FeOOH and Fe2O3. The results obtained by these methods showed what pigments can be found in make-up samples, what their sizes and shapes are. It has been shown that the smaller the pigments are, the higher the viscosity and yield stress of the final product. The higher these quantities, the harder it is to handle the product.
38

Svařování heterogenních spojů laserem / Welding of heterogeneous joints by laser

Charvátová, Eliška January 2021 (has links)
This diploma thesis deals with welding of two dissimilar materials by laser. The samples were welded by direct beam guidance and wobbling, with and without using high alloy filler material and with the use of a diffusion barrier in the form of nickel. Welding was done with different shielding atmospheres. Nondestructive (VT, PT, UT-PA, RT) and destructive tests were performer (tensile test at room and elevated temperatures, microhrardness). Metalography was suplemented by EDX analysis of selected elements.
39

Tlakový senzor typu MEMS využívající nanokompozity / MEMS pressure sensor utilizing nanocomposites

Šeda, Miroslav January 2008 (has links)
The main goal of this work is to introduce with the basic technologies of manufacturing MEMS (Micro-electro-mechanical-systems). Further there is mentioned properties and manufacturing of CNT (Carbon nanotubes), used in manufacturing of capacitance pressure sensor.
40

Multimodální registrace obrazů sítnice / Multimodal retinal image registration

Štohanzlová, Petra January 2011 (has links)
This work deals with possibilities of registration of retinal images from different mo-dalities, concretely optical coherence tomography (OCT), scanning laser ophthalmoscopy (SLO) and fundus camera. In first stage is the interest focused on registration of SLO and fundus images, which will serve to determine area of interest for consecutive registration of OCT data. The final stage is finding correct location of OCT B-scans in fundus image. On the basis of the studied methods of registration was chosen method making use of computation of correlation coefficient for both cases. For finding optimal parameters of registration is used searching through whole space of parameters. In partial stages of the work was created algorithm for alignment of B-scans followed by detection of blood vessels and also simple algorithm for detection of blood vessels from fundus image. For more transparent registration the graphical user interface was created, which allows loading input images and displaying the result in several possible forms.

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