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Mnohoúrovňové modelování geomateriálů a iterační řešiče
Blaheta, Radim ; Byczanski, Petr ; Harasim, Petr
The knowledge of microstructure in combination with properties of the constituents and mathematical modelling can be used for investigation of the properties of geomaterials at application scale. We investigate problems with both deterministic knowledge of microstructure, derived from X-ray CT scans, and stochastic one. The stochastic generation is also used for a systematic study of robustness of iterative solvers, particularly for Schwarz methods for PDE problems discretized by mixed FEM.
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Distributed Artificial Life Simulator
Weiss, Martin ; Kočí, Radek (referee) ; Martinek, David (advisor)
Along with the artificial intelligence modelling and related studies, distributed computing ranks amongs the most discussed scientific topics nowadays and one can be certain that it will not fade away anytime soon. This work is also concerned about the above mentioned topics, more precisely its its main goal is to design and implement a distributed artificial intelligence simulator. The mentioned application was realized during as an firm part of this work and some benchmarks were run to determine and observe some properties inherent to distributed systems. The actual realization takes into account different approaches to distributing simulation resources. The final product did not prove as that convenient for simulation of rather simple AI models, which it if fact, even slowed down at times. In the future the project should be aimed towards more computationally challenging problems, that can truly use the capacity and advantages of such a computational system.
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Volumetric model of human vocal folds
Vampola, T. ; Horáček, Jaromír
The article describes the vollumetric 3D FE model of real human vocal folds in a defined phonation position. The model was developed from the CT images of the plaster casts obtained by a special procedure during experiments with the excised human larynges, when the phonatioon caused by the airflow was suddenly stopped without changing the position of the fixed larynx. The model is determined for studies of dynamical stresses in the vocal fold tissue during vocal folds collisions.
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Viscometric study of L-Lysine- and 6-aminocaproic acid-hyaluronan systems behavior within the range of low aminoacids concentrations
Šimáčková, Marcela ; Běťák, Jiří (referee) ; Chytil, Martin (advisor)
This bachelor thesis investigates the interaction between high-molecular weight hyaluronic acid (1.75 MDa HA) and amino acids, particularly lysine and 6-aminocaproic acid. The interactions should occur between the carboxyl groups of HA carrying a negative charge and a positive charge located on the nitrogen atom of the protonated amino acids. The presence of these interactions would mean the possibility of establishing bioactive compounds, e.g. drugs, on hyaluronic acid, in which it would act as a targetting carrier. The interactions were examined at low concentrations for both aminoacids, i.e. below 10 mmoldm-3, and for 6-aminocaproic acid also at high aminoacid concentrations, i.e. above 20 mmoldm-3. The presence of interaction was investigated using not only rheology, but also by measuring pH and conductivity. Based on this research, the interactions manifested in terms of a decrease in the system viscosity.
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Current position of the Czech secondary vocational education without leaving examination and the possible solutions of its problems
Votavová, Tereza ; Kubelková, Karina (advisor) ; Petrášek, František (referee)
This bachelor thesis defines contemporary situation of vocational training (higher secondary education without leaving examination) in the Czech Republic and defines its main problems from the sides of state, firms and potential interested persons in education. The principal aim is offer the conception of 3 types of defined solutions of recent situation -- system alternation, reformation and parametric alternation. The thesis builds on the OECD's paper - OECD Reviews of Vocational Education and Training, but OECD's solutions are limiting by current paradigm. For the definition of the problem is necessary to describe its background, therefore the theoretical part is fixed on adjustment of the secondary-school's systems of the vocational training in the Czech Republic and in the whole world. The practical part of the thesis as the first analyzes the demand of students and employers in the Czech Republic for vocational skills and shows the preferences of both groups and the involvement of the state. According to ascertained information is explored if there are problem in the vocational training (without the leaving examination), and if is a necessity to solve it. The advantages and disadvantages of the Czech vocational training are analyzed and due to the solutions of the problems can be searching. The impact and influence of the present economic crisis on the standards and position of the vocational training on the educational market is evaluated. At the last is analyzed possible solutions contemporary situation with 3 possible concepts -- alternation with change of all system, alternation of reformation and parametric alternation.
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Suburbanization of rural space (case study of the village Dolní Třebonín)
DRŠKOVÁ, Markéta
This diploma work consists of two parts. The theoretic part literary summary deals with the question of suburbanization and the practical part, in which the survey of suburbanization in model area Dolní Třebonín was conducted. In the theoretical part, I firstly mention the types of suburbanization, where we can distinguish residential and commercial suburbanization. Secondly I talk about phases of urbanization process. The previously mentioned suburbanization is a second phases. Then I focus on consequences of suburbanization, which are mostly negative. Due to the fact that process of suburbanization can be regulated I also describe some influential people and institutions that can reduce the negative effects. For a better imagination of developing suburbanization in Czech Republic I also describe the actual situation of this process. In the last chapter of literary summary I point at the problems of migration, which is closely connected with the process of suburbanization. Practical part contains the description of model area and also the evaluation of results taken out of the questionnaire survey. The newly checked results were used to indicate the impacts of suburbanization in the researched area, which was the main aim of my diploma work.
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Identification of the parameters of an electroencephalographic recording system
Svozilová, Veronika ; Sekora, Jiří (referee) ; Mézl, Martin (advisor)
Elektroencefalografický záznamový systém slouží k vyšetření mozkové aktivity. Na základě tohoto vyšetření lze stanovit diagnózu některých nemocí, například epilepsie. Účelem této práce bylo zpracování signálu z toho systému a vytvoření modelového signálu, který bude s reálným signálem porovnán. Uměle vytvořený signál vychází z Jansenova matematického modelu, který byl dále implementován v prostředí MATLAB a rozšířen ze základního modelu na komplexnější zahrnující nelinearity a model rozhraní elektroda – elektrolyt. Dále bylo provedeno měření signálů na EEG fantomu a následná identifikace parametrů naměřených signálu. V první fázi byly testovány jednoduché signály. Identifikace parametrů těchto signálů sloužila k validaci daného EEG fantomu. V druhé fázi bylo přistoupeno k testování EEG signálů navržených podle matematického Jansenova modelu. Analýza veškerých signálů zahrnuje mimo jiné časově frekvenční analýzu či ověření platnosti principu superpozice.
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Quality of hydrophobic domains in polyelectrolyte-surfactant system
Holínková, Petra ; Vala, Martin (referee) ; Mravec, Filip (advisor)
In this bachelor thesis were studied the photophysical properties of four fluorescent probes depending on the viscosity of their surroundings by the fluorescence spectroscopy. For probes DPH, DPB a perylene was determinated dependence of fluorescence anisotropy and for P3P dependence of ratio excimer/monomer on the viscosity of the sample. Anisotropy probes DPH and perylene were also used to study interaction between hyaluronan and cationic surfactant CTAB (concentration below CMC) in aqueous solution and 0,15 M NaCl. Information about forming hydrophobic domains were obtained by measurement of fluorescence intensity and anisotropy depending on the concentration of CTAB in the sample. It was found that in an aqueuos solution, after the initial addition of CTAB to hyaluronan formed small hydrophobic domains linked to chain of hyaluronan. Increasing concentration of CTAB leads to the formation of gel and phase separation. After addition of NaCl leads to reorganization of this system and probably the formation of free micelles in the solution with higher concentration of CTAB.
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Interaction between TiAl melt and coated oxide refractories
Dočekalová, Kateřina ; Dlouhý, Antonín ; Zemčík, L. ; Fiala, J.
The present study focuses on reactions between ceramic crucibles and molten TiAl intermetallics. Coating strategies are investigated that exhibit a potential in slowing down the decomposition of the crucible wall. Uncoated crucibles (system TiAl melt - Al2O3 crucible) and crucibles with the coat (system TiAl melt - CaO coat - Al2O3 crucible) were used in melting and casting experiments. The reference state of the coated crucible before the melting trial was also investigated. Results of the SEM, EDAX and X-ray diffraction analysis contributed to the identification of the reaction zone and its chemical composition. The melt contamination with oxide inclusions results from the erosion process in which individual components of the melt diffuse along grain boundaries of the refractory and activate chemical reactions that decompose the crucible wall. Assessment of thermodynamic parameters associated with the chemical reactions helped in identifying the nature of the erosion process.
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