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ELECTRON BEAM REMELTING OF PLASMA SPRAYED ALUMINA COATINGS
Matějíček, Jiří ; Veverka, J. ; Čížek, J. ; Kouřil, J.
Plasma sprayed alumina coatings find numerous applications in various fields, where they enhance the properties of the base material. Examples include thermal barriers, wear resistance, electrical insulation, and diffusion and corrosion barriers. A typical structure of plasma sprayed coatings, containing a multitude of voids and imperfectly bonded interfaces, gives them unique properties - particularly low thermal conductivity, high strain tolerance, etc. However, for certain applications such as permeation barriers or wear resistance, these voids may be detrimental.\nThis paper reports on the first experiments with remelting of plasma sprayed alumina coatings by electron beam technology, with the purpose of densifying the coatings and thereby eliminating the voids. Throughout the study, several parameters of the e-beam device were varied - beam current, traverse velocity and number of passes. The treated coatings were observed by light and electron microscopy and the thickness, structure and surface morphology of the remelted layer were determined and correlated with the process parameters. Based on the first series of experiments, the e-beam settings leading to dense and smooth remelted layer of sufficient thickness were obtained. In this layer, a change of phase composition and a marked increase in hardness were observed.\n
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Modelling, parameter estimation, optimisation and control of transport and reaction processes in bioreactors.
ŠTUMBAUER, Václav
With the significant potential of microalgae as a major biofuel source of the future, a considerable scientific attention is attracted towards the field of biotechnology and bioprocess engineering. Nevertheless the current photobioreactor (PBR) design methods are still too empirical. With this work I would like to promote the idea of designing a production system, such as a PBR, completely \emph{in silico}, thus allowing for the in silico optimization and optimal control determination. The thesis deals with the PBR modeling and simulation. It addresses two crucial issues in the current state-of-the-art PBR modeling. The first issue relevant to the deficiency of the currently available models - the incorrect or insufficient treatment of either the transport process modeling, the reaction modeling or the coupling between these two models. A correct treatment of both the transport and the reaction phenomena is proposed in the thesis - in the form of a unified modeling framework consisting of three interconnected parts - (i) the state system, (ii) the fluid-dynamic model and (iii) optimal control determination. The proposed model structure allows prediction of the PBR performance with respect to the modelled PBR size, geometry, operating conditions or a particular microalgae strain. The proposed unified modeling approach is applied to the case of the Couette-Taylor photobioreactor (CTBR) where it is used for the optimal control solution. The PBR represents a complex multiscale problem and especially in the case of the production scale systems, the associated computational costs are paramount. This is the second crucial issue addressed in the thesis. With respect to the computational complexity, the fluid dynamics simulation is the most costly part of the PBR simulation. To model the fluid flow with the classical CFD (Computational Fluid Dynamics) methods inside a production scale PBR leads to an enormous grid size. This usually requires a parallel implementation of the solver but in the parallelization of the classical methods lies another relevant issue - that of the amount of data the individual nodes must interchange with each other. The thesis addresses the performance relevant issues by proposing and evaluation alternative approaches to the fluid flow simulation. These approaches are more suitable to the parallel implementation than the classical methods because of their rather local character in comparison to the classical methods - namely the Lattice Boltzmann Method (LBM) for fluid flow, which is the primary focus of the thesis in this regard and alternatively also the discrete random walk based method (DRW). As the outcome of the thesis I have developed and validated a new Lagrangian general modeling approach to the transport and reaction processes in PBR - a framework based on the Lattice Boltzmann method (LBM) and the model of the Photosynthetic Factory (PSF) that models correctly the transport and reaction processes and their coupling. Further I have implemented a software prototype based on the proposed modeling approach and validated this prototype on the case of the Coutte-Taylor PBR. I have also demonstrated that the modeling approach has a significant potential from the computational costs point of view by implementing and validating the software prototype on the parallel architecture of CUDA (Compute Unified Device Architecture). The current parallel implementation is approximately 20 times faster than the unparallized one and decreases thus significantly the iteration cycle of the PBR design process.
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Miřenka Čechová
Janečková, Kateřina ; PETIŠKOVÁ, Ladislava (advisor) ; SOPROVÁ, Jana (referee)
Monographic work focuses on artistic creation Miřenka Čechová, one of the
the leading personalities of our contemporary stagecraft. Her personal and
artistic development started when she began studying dance and continued to
mimic and physical theater. Material presents her contribution to
contemporary Czech scene physical theater and refers to her international
success. Work observes her role like co-founder of physical theaters Theatro
Pantomissimo and Spitfire Company and to presents the work of these
physical theaters and reveals the working and teaching methods in the
preparation of copyright performances.
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Association of Idependent Theatres of the Czech Republic – Analysis and Description of the Current State
Bodoríková, Markéta ; KAŠPAR, David (advisor) ; PROKOP, Petr (referee)
The thesis is focused on newly established Association of Independent Theaters of the Czech Republic, officially using the abbreviation AND ČR. The aim of the thesis is to describe formation of the association, its current state, future plans and its functioning. The first part examines the term “independent professional theater” and briefly characterizes selected organizations from the Czech Republic and Europe with the potential to meet with the AND ČR in the cultural area in future. In the following parts were researched needs of independent professional scene in Prague and was described the needs analysis for the field of “independent” theater from the year 2013. The thesis describes the development of AND ČR, its activities up to current stage, organizational structure and future short-term plans. In the final part of the thesis, there is defined the management system of the association and established its possible improvements so the AND ČR would become the leading organization representing independent professional theaters in the Czech Republic.
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FAUST AND JOB´S
Slezáková, Kateřina ; ULLRICHOVÁ, Daria (advisor) ; SÍLOVÁ, Zuzana (referee)
This thesis examins the nature of Faust’s inner ambivalence in the context of modern times. It tries to identify the basic traits leading to the feeling of emptiness. The authoress uses comparing the dramatic character of Faust with his biblical prototype of Job and one of the most successful entrepreneurs today Steve Jobs. Based on the comparison she contemplates the validity or mutation of the drawing theses nowadays. In the second part the authoress reflects the production of the project of Faust. Due to her specialization in the field of dramaturgy she pursues especially the process of the selection of particular dramatic situations, adjustments of dramatic text and the choice of suitable staging means.
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Fluidized-bed Combustion of Dry Stabilized Sewage Sludge in Oxy-fuel Mode
Moško, Jaroslav ; Pohořelý, Michael ; Durda, Tomáš ; Zach, Boleslav ; Šyc, Michal ; Svoboda, Karel
Sewage sludge is an inevitable waste stream from wastewater treatment and its disposal is complicated due to specific characteristics of its composition. Sewage sludge combustion/incineration is the only suitable way for disposal of large volumes of sewage sludge containing POPs and some heavy metals. Sewage sludge combustion reduces the volume of such waste and causes destruction of organic contaminants. Oxy-fuel combustion is a technology for simplifying CO2 sequestration from the flue gas by using nearly pure oxygen instead of air for the combustion. In order to control the combustion temperature, part of the flue gas is recycled to combustion chamber. The paper brings information about investigation of the effects of combustion temperature and concentration of oxygen in inlet combustion media on the emissions of NOx, N2O and SO2 in FB combustion of sewage sludge. The experimental results have shown that an increase in combustion temperature leads to an increase in NOx and to a decrease in N2O emissions in the temperature range 750–930 °C. The lowest SO2 emissions were measured in the temperature interval from 800 to 820 °C in all experiments with different oxygen concentration in inlet gas. It was found that when the oxygen concentration in inlet gas increased, the emissions of SO2 increased while emissions of NOx slightly decreased.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22016112214480 - PDF
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Comparison of Atmospheric Aerosol Volatility at a Suburban and Rural Measurement Site.
Kubelová, Lucie ; Vodička, Petr ; Schwarz, Jaroslav ; Makeš, Otakar ; Ždímal, Vladimír
One of the most important characteristics of atmospheric aerosols is their volatility. Volatility affects the formation, life time, and removal of aerosol particles (Huffman et al., 2009). Accurate description of volatility of atmospheric aerosols can lead to a better identification of their sources and it is also crucial for models incorporating condensation and aging of aerosols. However, there is still a lack of knowledge regarding aerosol properties such as volatility especially in case of organic aerosols. To increase our understanding of aerosols volatility, we have performed summer (21.8.-2.10.2012; 17.6.-18.8.2014) and winter (19.2.-28.5.2013; 9.1.-13.3.2014) measurement campaigns with a thermodenuder at a suburban site in Prague Suchdol and at a rural site Košetice, respectively.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22016102412230 - PDF
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Marketing plan
Nosálová, Lucie ; Štůsek, Jaromír (advisor) ; Ladislav , Ladislav (referee)
The goal of this thesis is to detect errors in the management of small family business, which basically does not use marketing. Following this finding should be to build an effective marketing plan. The diploma thesis is divided into theoretical part, which forms the basis for the analytical part. In the analytical part is described the company and there are also detect errors in the management that are caused by faulty marketing. To achieve results it is important to use several different types of analysis on which it is necessary to set new marketing goals, strategies, changes and projects. The aim is to provide business information and convince him that use of good marketing communication should lead to improve management efficiency and ultimatem increase profitability of the company, without the need to break away from the corporate goal of maximum efforts to build a pro-customer oriented service.
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Managerial skills
Červinková, Barbora ; Kříž, Josef (advisor) ; Zdeněk, Zdeněk (referee)
The theoretical basis of this thesis explains the terms closely associated with the management and managerial skills. Introductory part relates to approach the concept itself and the executive management, we are further broken down managerial functions, which are continuously illuminates to describe other skills, such as communication, goal setting, skills and coaching. The main point is to approach the concepts of soft and hard skills that managers should possess, or which should in the course of his practice to learn. Only by careful control of both of these groups of skills can lead to good organization. For a clearer explanation of the managerial skills included graphic view, which approximates the distribution of skills. In the second part, a practical part, described the situation with the existing skills of managers in the selected company. Thanks to the questionnaire, it is possible to measure the current level of acquired skills of managers at three levels and can be evaluated, what is the interest of improving individual skills, or whether managers feel sufficiently qualified for their job positions.
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Freezing technology of bull sperm in relation to its survivability and fertilization ability
Doležalová, Martina ; Stádník, Luděk (advisor) ; Jiří, Jiří (referee)
The aim of optimalization the insemination doses production is to provide the highest fertilization ability of spermatozoa during the demanding proces of processing fresh semen and its subsequent cryopreservation. Temperature changes causes spermatozoa damage during the cooling and freezing. Spermatozoa is exposed to cold shock and many others limiting factors, which leads to cell death and therefore to decline of fertilization ability of thawed insemination doses. For increasing spermatozoa resistance, exactly the plasma membrane resistance against cold shock was fraction of egg yolk LDL cholesterol (low density lipoprotein) at various concentrations into the comercially produced diluents added. It is believed that LDL acts possitively to plasma membrane and helps to maintain the fertilization ability of spermatozoa after thawing. Following step in the proces of insemination doses production is slow cooling of diluted semen and equilibration, when the straws are store at cooling box for 30 minutes to 240 hours. This period is necessary to penetrate of certain diluent components into the spermatazoa also maintain the balance between their intracellular and extracellular concentration. Also important is subsequent freezing temperature gradient of insemination doses. The most suitable freezing method is based on computer controlled temperature decline in freezing chamber which allows the precise control of ice crystals formation that could tear and kill the cell.
During 2012 to 2016 was repeatedly collected semen from the group of breeding bulls (n = 27, Holstein and Czech Fleckvieh breed) at AI centre. Semen which fulfill the standard entrance conditions in first step was evenly into several parts divided. For dilution the three types of comercially diluents AndroMed, Bioxcell and Triladyl with and without LDL addition were used. Into the diluents AndroMed and Bioxcell the concentration of LDL 4 %, 6 % and 8% into the dilent Triladyl 6 %, 8 % and 10 % was added. Diluted semen was filled into the glass capillares with volume 0,1 ml and temperature +4 °C. Subsequently the sample was placed to cold bath (0°C) for 10 minutes. Then the volume of capillare with physiological solution (37 °C) was mixed and for next 120 minutes was incubate. The effect of cold shock to proportion of live spermatozoa was evaluated by using Eosin and Nigrosine staining technique during heat test of spermatozoa survivability after spermatozoa heating and after 120 minutes of incubation.
The more suitable semen diluents which provide the higher spermatozoa resistance against cold shock were AndroMed and Bioxcell. Together the possitive effect of LDL addition into the diluents to lower decrease of proportion of live spermatozoa during heat test was found (P<0.05). The most suitable LDL concentration which had a favorable influence at spermatozoa resistance against cold shock was 6 % in diluent Bioxcell. Values of the proportion of live sperm were higher at the beginning of the heat test (+1.31% to + 3.2%) and after 120 minute incubation (+5.82% to +8.41%) compared to other diluents with and without addition of LDL.
In the next step the process of equilibration was optimized, is an important part of insemination doses production. The effect of the length of equilibration for subsequent fertilization ability of spermatozoa was evaluated using spermatozoa motility based of CASA and proportion of live spermatozoa after thawing and during heat survival test lasting 120 minutes (37 ° C). Suitable semen was diluted by comercially used diluent AndroMed based on soya lecithin, filled into the straws (0.25 ml), cooled and equilibrated in cooling box for 30, 120 and 240 minutes and freezed in programmable freezing box applying four types of freezing curves differing in temperature rate decline. There was used standard and by producer recommended 3. phase freezing curve, then 2. phase freezing curve, and 3. phase freezing curve with slower as well as rapid decline of temperature rate in freezing chamber, compared with standard freezing curve. The highest spermatozoa motility was found using 240 minutes of equilibration by +2.72% and +4.58% compared to other lengths of equilibration (P <0.05 to 0.01). The highest proportion of live spermatozoa was found using 120 minutes of equilibration (+6.87 % and +8.68 %). The highest average spermatozoa motility during heat test after thawing was achieved by using 2. phase freezing curve (from +2.97% to +10.37%, P <0.05), also in the proportion of live spermatozoa (from + 4.37% to +8.82%, P <0.01). When evaluating interaction between the length of equilibration and freezing curve (standard 3. phase and 2 . phase freezing curve), the highest average spermatozoa motility and proportion of live spermatozoa using 240 minutes of equilibration by both freezing curves was reached, there was no statistically significant differences. As well as, in all evaluated parts of this study the individual differences between ejaculate of bulls and within semen from one bull (P <0.05) as secondary effect were found.
To maintain good fertilization ability of semen during cryopreservation is necessary to increase the spermatozoa resistance against cold shock using addition of correct concentration of LDL into the commercially used diluents AndroMed and Bioxcell. Subsequently the fertilization ability of insemination dose is influenced by cooling, the length of equilibration and freezing. The length of equilibration 120 minutes and more as well as gentle way of freezing according to freezing curve, which ensures a gradual decrease of temperature in freezing chamber provided the higher average spermatozoa motility and proportion of live spermatozoa.
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