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Using Reinforcement learning and inductive synthesis for designing robust controllers in POMDPs
Hudák, David ; Holík, Lukáš (referee) ; Češka, Milan (advisor)
Jednou ze současných výzev při sekvenční rozhodováním je práce s neurčitostí, která je způsobena nepřesnými senzory či neúplnou informací o prostředích, ve kterých bychom chtěli dělat rozhodnutí. Tato neurčitost je formálně popsána takzvanými částečně pozorovatelnými Markovskými rozhodovacími procesy (POMDP), které oproti Markovským rozhodovacím procesům (MDP) nahrazují informaci o konkrétním stavu nepřesným pozorováním. Pro rozhodování v takových prostředích je nutno nějakým způsobem odhadovat současný stav a obecně tvorba optimálních politik v takových prostředích není rozhodnutelná. K vyrovnání se s touto výzvou existují dva zcela odlišné přístupy, kdy lze k problému přistupovat úplnými formálními metodami, a to buď s pomocí výpočtu beliefů či syntézou konečně stavových kontrolérů, nebo metodami založenými na nepřesné aproximaci současného stavu, reprezentované především hlubokým zpětnovazebným učením. Zatímco formální přístupy jsou schopné dělat verifikovatelná a robustní rozhodnutí pro malá prostředí, tak zpětnovazebné učení je schopné škálovat na reálné problémy. Tato práce se pak soustředí na spojení těchto dvou odlišných přístupů, kdy navrhuje různé metody jak pro interpretaci výsledku, tak pro vzájemné předávání nápověd. Experimenty v této práci ukazují, že z této symbiózy mohou těžit oba přístupy, ale také že zvolený přístup ke trénování agentů už sám o sobě řádově překonává současné systémy pro trénování agentů na podobných úlohách.
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Study of conjugates of sphingolipids with hyaluronic acid and their application on the skin
Juhaščik, Martin ; Kováčik, Andrej (advisor) ; Gajdziok, Jan (referee) ; Miletín, Miroslav (referee)
1 ABSTRACT Charles University, Faculty of Pharmacy in Hradec Králové Training Workplace Department of Pharmaceutical Technology Doctoral Degree Program Pharmaceutical Technology Candidate Mgr. Martin Juhaščik Supervisor doc. PharmDr. Andrej Kováčik, Ph.D. Advisor Gloria Huerta-Ángeles, Ph.D. Title of Doctoral Thesis Study of conjugates of sphingolipids with hyaluronic acid and their application on the skin The main goal of this study was to systematically design and subsequently prepare conjugates of hyaluronic acid (HA) with selected sphingolipids, which could find application in their topical administration during physiological decline of skin functions. In this study, phytosphingosine and ceramide were chemically linked to HA via biocompatible linkers, enabling successful modification of HA into a hydrophobized conjugate of sphingolipid-linker-hyaluronate. The preparation of succinylceramide-hyaluronate conjugate was found to be the most effective. The developed method of preparing the conjugate using mixed anhydrides brings several advantages, including the possibility of scaling up the preparation and conducting reactions in an aqueous environment. The method was effective over a wide range of molecular weights, from 6 to 442 kgmol-1, achieving a degree of substitution of up to 14.2 %, surpassing the...
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Biofunctionalization of water soluble CdTe quantum dots
Šibíková, Anna ; Drbohlavová, Jana (referee) ; Pekárková, Jana (advisor)
This bachelor thesis is focused on the research on biofuncionalization of water-soluble glutathione modified CdTe quantum dots (QDs). The thesis is divided into three parts. The first part is a theoretical introduction to the QDs and their synthesis, modifications and applications in biology together with an introduction to proteins and bioconjugation of QDs and BSA. In the second part I present the experimental results of water-soluble glutathione modified CdTe-GSH QDs preparation. The QDs were cleaned and bioconjugated with BSA at different concentrations. This is described in the third part of the thesis. I also discuss the obtained experimental results in the frames of available literature.
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Synthesis and sintering of zirconia based ceramics for biomedical applications
Jahodová, Daniela ; Novotná, Lenka (referee) ; Částková, Klára (advisor)
The present thesis focuses on the preparation of tetragonal zirconia doped with yttria oxide, ceric dioxide, and magnesium oxide. In its theoretical part the thesis covers the characteristics of doped ceramics, the possible methods of powders preparation and of their further processing. The experimental part describes the precipitation synthesis of zirconia in base environment and further processing for ceramics. Also studied were the influences of dopant and of the processing technique used on the phase composition and microstructure of the resulting ceramics. To describe the powder structure, the thermal, dilatometric, surface area, and x-ray analyses were performed; as well as both the scanning and transmission electron microscopy employed. Dry processed ceramics showed the average grain size of 87–94 nm and the relative density in the range of 84,0–99,3 %. In comparison, the ceramics produced of hydrothermally synthesised powders proved the average grain size of 75–85 nm and the relative density between 92,7-99,9 %. As the next step, samples were subjected to low-temperature degradation for the time of 5 and 15 hours. Samples consisting of pure tetragonal ZrO2 were resistant to 5 and 15 hours of low-temperature degradation at 180 °C.
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Optimization of supporting cryptographic operations using hardware
Čurilla, Jakub ; Smékal, David (referee) ; Cíbik, Peter (advisor)
This work deals with the description of FPGA architecture circuits, their structure, VHDL language, FPGA design flow, cryptography and cryptographic operations, and subsequent implementation and realization of support functions for cryptographic operations in VHDL language, their time and performance analysis, and mutual comparison.
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Preparation of modified tricalcium aluminate phases and study of their hydratation processes
Vávrová, Alžběta ; Koplík, Jan (referee) ; Másilko, Jiří (advisor)
This diploma thesis deals with the preparation of modified tricalcium aluminate phases using sodium ions, and the study of their hydration processes and products. The X-ray diffraction analysis, isothermal calorimetry, laser diffraction, and scanning electron microscopy with energy dispersion analysis were used to solve this task. The preparation of modified tricalcium aluminate phases using high temperature methods has been described in the experimental section. Furthermore, the X-ray diffraction analysis was used to determine the purity of the prepared phases and the scanning electron microscopy with energy dispersion analysis was used to define the volume of sodium. Laser diffraction was used to measure a particle size distribution in the individual phases. Subsequently, hydration of the pure phases was performed in an isothermal calorimeter. It was followed by hydration of phases in the presence of different gypsum content and then in the presence of saturated portlandite solution. Hydration of some samples was stopped in order to better understand the hydration process. Hydration products were studied by X-ray diffraction analysis. The obtained results were compared with each other and the influence of sodium ions on both the structure of the prepared phases and the course of hydration and its products has been discussed. The effect of adding different volumes of gypsum and portlandite on the course of hydration of the individual phases was also compared.
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Automated Synthesis of Tree Structures from Real Data
Želiar, Dušan ; Fiedor, Tomáš (referee) ; Smrčka, Aleš (advisor)
This masters thesis deals with analysis of tree structure data. The aim of this thesis is to design and implement a tool for automated detection of relation among samples of read data considering their three structure and node values. Output of the tool is a prescription for automated synthesis of data for testing purposes. The tool is a part of Testos platform developed at FIT BUT.
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Lanthanocene Catalysts for Synthesis of Polymers Applicable in Medicine
Slanina, Ondřej ; Kábelová, Božena (referee) ; Richtera, Lukáš (advisor)
The theoretic part of the thesis focuses on materials used in medicine. The metallic, ceramic, glass-ceramic and polymer materials are systematically described. The biocompatibility of the materials and possible threads of their usage for manufacturing of medicinal devices and implants are emphasized in the discussion. The work is focused especially on polymer materials. Different types of polymerizations are summarized with the accent on the preparation of biodegradable materials. In the practical part the synthesis of two organometallic bis(pentamethylcyclopentadienyl) sandwich complexes with holmium and gadolinium as a central atom designed for preparation of materials suitable for biomedicine is proposed.
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Fabrication of dental glass-ceramics
Hasalíková, Tereza ; Dlabajová, Lucie (referee) ; Bartoníčková, Eva (advisor)
This bachelor´s thesis deals with the study of glass-ceramic materials and their use in dentistry. Nowadays, studies are placed on health harmless of the material, the biological ability to adapt to the host tissue, mechanical properties, affordability, easy and fast production, aesthetics and quick recovery of the patient. The theoretical part of the work deals with various materials from various input materials used for dental substitutes. Special attention is paid to glass-ceramic and ceramic biomaterials, their preparation, heat treatment and health testing. The experimental part deals with the preparation of powder materials by the sol-gel method. Of the larger number of samples, those were selected for gelation and showed good XRD and heat microscopy results. The selected samples were subsequently subjected to heat treatment to form a glass ceramic material. The products were characterized by XRD phase composition in terms of phase temperature behavior by TG-DTA analysis, heat microscopy and SEM morphology analysis of prepared particle.
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