The thesis is focused on wood dust generated during sanding modified beech. The analysis concerns the characteristics and composition of this dust. The thesis addresses also the danger for human health exposed to the wood dust and its impact on the work environment. The theoretical part is focused on properties and biological effects of airborne dust on the human body as well as the thermal modification of wood. The experimental part was carried out on a test stand to simulate standard sanding. For our experiment three samples were selected, namely a modified beech at 180 °C, 200 °C and a native beech. In order to evaluate the incidence of wood dust, a methodology was designed to determine the representation of individual fractions of wood particles. Very fine particles (particles smaller than 100 micrometres) were subjected to microscopic and probabilistic analysis.

1 ABSTRACT: This study is dedicated to the study of nucleation of sulphuric acid and water, which presents the key process associated with secondary aerosol formation via gas to particle conversion. We investigated the nucleation rates, new aerosol particles formation and growth dynamics of newly nucleated particles. These processes were explored in both laboratory and field experiments. In the laboratory measurements, we explored the H2SO4 - H2O nucleation rates and growth rates of newly formed particles under well-defined conditions and we also investigated the effect of experimental conditions on particle growth dynamics. Furthermore, we proposed a model, which predicts the particle growth and accounts for condensation of H2SO4, H2O and NH3. The comparison of experimental growth rates with atmospheric ones was made and resulting implications of the chemical nature of compounds involved in the early growth of nucleated particles is also presented. To investigate the atmospheric H2SO4 - H2O nucleation and new particle formation, we analysed a two-year long dataset of particle number size distributions, obtained from a urban background station in Prague Suchdol. A special attention was given to a recently reported special feature of particle growth dynamics - a particle shrinkage following previous new...

The aim was to identify and assess the structure of practical ration on the particle separa-tor in holdings breeding more than 3,300 pieces of dairy. For the experiment was elected Penn State particle separator (PSPS), developed in 2002, and its improved model from 2013. The attempt took place at the Farm Majcichov, a.s. the Slovak republic. The total time of the experiment was 16 weeks. During the experiment, the observed structure of the diet, gluttony and performance of dairy cows, the number of animals in the group and the average days of lactation in the group. The qualitative composition of the milk was evaluated using data provided analyzes of milk from dairies. Data were averaged for each week. In the reporting period, the particle size of the feed stable, there were no variations in the structure and content of fiber, it was not possible to assess their impact on the performance of dairy cows. On the upper sieve (19 mm) caught an average 2,5 +- 0,83 % of particles, on the middle sieve (8 mm) 48,7 +- 7,44 % of particles, on the lower sieve (1,18 mm) 26,3 +- 1,98 % of particles and the bottom pen of the separator was sie-ved 22,5 +- 7,18 % of particles. Daily performance was on average 35 liters milk with 3,77 % of fat and 3,25 % of protein. It was found that the content of milk fat and other components of milk had a great influence heat stress in dairy cows.

Dlouhodobé vdechování částic může přispívat ke vzniku nebo zhoršení nejrůznějších plicních onemocnění. Na druhou stranu, vdechování léčiv je často používanou metodou podávání léků proti astmatu a jiným nemocem dýchacího ústrojí. V obou případech je důležité dobře porozumět mechanismům, na jejichž základě funguje pohyb částic a jejich usazování v dýchacích cestách. Cílem této disertační práce bylo získat nová experimentální data depozice částic a analyzovat vliv tvaru částic a průtoku vzduchu na depozici. Byla studována depozice porézních a vláknitých částic v realistickém modelu dýchacích cest. Porézní částice byly vyrobeny různými metodami, např. sprejovým sušením nebo metodou krystalizace. Takto vyrobené částice byly použity při depozičních experimentech. Detekce částic byla provedena pomocí UV/VIS spektrofotometrie. Vláknitý aerosol byl vytvořen rozdrcením skelné vaty. Takto vzniklé vláknité částice byly několikrát prosety přes řadu sít a dále roztříděny podle délky pomocí klasifikátoru pracujícím na principu dielektroforézy. Následná depozice byla vyhodnocena použitím mikroskopie s fázovým kontrastem. Ke zrychlení analýzy byl vyvinut program, který dokáže na základě analýzy obrazu najít a spočítat vlákna. Výsledky experimentu byly použity k určení depozičních charakteristik. S jejich pomocí pak byl kvantifikován vliv tvaru částic a průtoku na míru usazování. Depoziční účinnost částic rostla v závislosti na Stokesově čísle, což poukazuje na vliv setrvačnosti při usazování částic. Bylo prokázáno, že depoziční účinnost porézních částic je podobná té u částic kulových při stejném Stokesově čísle. Vláknité částice se usazovali méně efektivně v porovnání s kulovými částicemi majícími stejné Stokesovo číslo. Jelikož byly okrajové podmínky dostatečně popsány a model plic je k dispozici i v digitální podobě, je možné data použít k validaci výsledků numerických simulací.

Aseptic loosening due to polyethylene wear presents one of the most frequently occurring joint replacement complications requiring a revision surgery. Numerous scientific works and publications deal with the issue of morphology, determination and distribution of wear particles. Few studies, however, determine reliably amounts of particles in individual periprosthetic zones. The objective of this work was to evaluate the correlation between amounts of wear particles and periprosthetic osteolysis findings. Description of distribution of these particles in the surroundings of joint replacement presented further objectives of the work. Wear particles were isolated from granuloma obtained during revisions of total hip replacements. Amounts of wear particles were determined using IRc. These findings were correlated with X-ray examinations and intraoperative findings. Method of progressive enzymatic degradation of tissue was used in order to describe wear particles distribution in polyethylene granuloma and surrounding periprosthetic tissues. Results showed uneven incidence of wear particles in the surroundings of the total joint replacement. The incidence correlated with X-ray examinations and intraoperative findings. Distribution of particles was described as well as new determination methods and further...

Title: Formation and transformation of atmospheric aerosol in boundary layer Author: Mgr. Adéla Holubová Šmejkalová Institute: Institute for Environmental Studies Supervisor: Ing. Vladimír Ždímal, Dr., Institute of Chemical Process Fundamen- tals of the CAS Training workplace: Institute of Chemical Process Fundamentals of the CAS Abstract: The experimental measurement of aerosol clusters from 1.17 nm in size was carried out from August 2016 till December 2018 at the National Atmospheric Observatory Košetice. Atmospheric conditions leading to aerosol clusters stabili- zation, fresh particles formation and particle growth were analyzed. Data of days with no new particle formation confrmed the connection between mixing layer height development and decrease of total aerosol number concentration together with lower gaseous pollutant concentrations. On the contrary, new particle for- mation process overcomes dilution of the atmosphere by increasing the number of freshly nucleated particles. Only decreasing gaseous pollutant concentrations were observed during these events. The atmospheric boundary layer was high du- ring new particle formation events that can mean enrichment of the atmosphere by other components transported by long-range transport or some transfer from the free troposphere. The measurement in...

Spinning-particle motion is studied, within the pole-dipole approximation, in algebraically special space-times of type N, III and D. The spin-curvature interaction is analysed for the Pirani and Tulczyjew spin supplementary conditions; for N and D types, the condition is related to a relative acceleration of two near observers separated in the direction of particle's spin. For Tulczyjew's condition, the momentum-velocity relation is also studied as well as its consequences for the spin-curvature interaction. Finally, the type of motion is mentioned for which both the supplementary conditions considered are equivalent.

In 2009 Bañados, Silk and West described the possibility of principally unbounded collision energies in the centre-of-mass frame for the particle collisions in the vicinity of black holes. Their work attracted a big response. This thesis aims to summarise the results of a number of the articles about the topic and puts these results into a new, broader context. It also presents some generalisations of the existing results, especially for models of magnetised black holes. The main subject of interest is the question, whether the unbounded collision energies can be achieved in a single-scattering or multiple-scattering process which was first formulated by Grib, Pavlov and Zaslavskii. Variety of methods is summarised. A considerable attention is paid to the limiting near-horizon description, which is further developed in order to derive new links and relations among known results, particularly between the purely theoretical work dealing with the geometry of degenerate horizons and their vicinity and more astrophysical articles about magnetic fluxes. Powered by TCPDF (www.tcpdf.org)

Multimedia exploration is addressing the issue of searching within multimedia collections where the data is not annotated, the user is not able to formulate the text query, does not have any example data or wants to get quickly acquainted with the features of the collection. Part of the exploration is also the presentation of the results which is the main contribution of this thesis. The relations between the pictures in the exploration results are transformed into a graph which is visualised through a particle physics model. To visualize a large number of pictures, it is necessary to optimize the calculation. This thesis describes the optimization of both the basic algorithms and their adaptations for the need of multimedia exploration. The calculation layout is available in 2D and 3D space. Powered by TCPDF (www.tcpdf.org)

Title: Live-cell tracking in time-lapse sequences Author: Tomáš Zámečník Department: Department of Software and Computer Science Education Supervisor: RNDr. Michal Šorel Ph.D., Oddělení zpracování obrazu ÚTIA AV ČR Abstract: This diploma thesis deals with methods of tracking particles in image sequences. It's goal is to design and implement a complete system for tracking of live cells, their motion and division. The thesis uses conclusions of published scientific papers, studies their application and analyzes possibilities for their mo- difications or improvement. As a result, there are two applications. First of them is a demonstrational pro- gram, provided as an attachment of this thesis. Second implementation is a mo- dule of commercial software NIS-Elements, by Laboratory Imaging, Ltd., which is used by both scientific and commercial institutions in the whole world. Keywords: cell tracking, particle tracking, cell division 1