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Optical Field Evaluations for Hologram Synthesis
Fedorko, Matúš ; Polok, Lukáš (referee) ; Zemčík, Pavel (advisor)
The primary concern of this work is computer generated holography, in particular accelerating computation of synthetic holograms by means of modern-day massively parallel graphics chips. It starts by introducing fundamental holography principles together with mathematical and physical concepts behind it. Following discussion then deals with OpenCL, which is a relatively new, but well recognized standard for GP-GPU programming. Finally, the last two chapters of this work give an overview of problem analysis and its implementation in C++.
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Workstation for optical interferometry
Blecha, Martin ; Honec, Peter (referee) ; Janáková, Ilona (advisor)
This thesis is specialized on composition of workplace for experiments flowing from optical interferometry. Here are described laboratory exercise servant for demonstration basic principles of interferometry. In more details is described method measurement of height profile objects with method white light interferometry.
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Automation of measurement of disturbance influence on xDSL technologies
Röszler, Pavel ; Číž, Radim (referee) ; Šilhavý, Pavel (advisor)
This work focuses on interference of DSL transmission, measurement and testing with Spirent noise generator and injection unit. Deals with proposition of automated measurement of transmission bit rate dependency on wireline lenght and noise type and level. In theoretical part are described ADSL technology and noise types. Following part focuses on measurement setup and description of wireline simulator units E414 and 8234, gene- rator DLS-5800 a injection unit DLS-5410DC by Spirent company. Main part describes generator and injection unit control software and remote control commands, which are used for automated measurement. There are also described xDSL Measure tool software, which is using for automated measurement with wireline simulators and upgrade, which implements remote communication with generator a injection unit, for remote control and automatic changing noise types generated at the output.
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Minimizing the effect of interference on wireless network
Doležal, Jan ; Kyselák, Martin (referee) ; Škorpil, Vladislav (advisor)
This thesis is concerned the technology with technologies of transfer through wireless devices. It is about possibilities of optimization of transfer in wireless net, especially of the reduction of interference influence. The first part is about theory and the standards development of wireless technology. There are methods and principles used in wireless technologies. The second part is a practical measuring and testing of an internal wireless net, with the emphasis being on the source of interference influence. Measuring was focused on interference between access points and was not about meteorological influence. It continues with theory and testing of interference of the microwave oven in our wireless net. Then, it is a practical demonstration of interference in an external environment. There are practical examples of interference between different providers’ nets on the same area and solutions to prevent or to cancel this interference. In next part of work the wireless net is parsed and described in a given territory. Here is described the way how to precede the reciprocal interference and eventually how this mutual disturbance suppress. Consequently, our net is optimized for customer growth and for today’s options of newer and more powerful components for wireless transfer. Finally there are two laboratory tasks. The first one is about practical measuring and testing of wireless net’s parameters and the second one is about simulation of wireless networks in the Opnet program.
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WLAN and Bluetooth Systems Coexistence
Mikulka, Jan ; Hanus, Stanislav (advisor)
The dissertation thesis deals with a WLAN and Bluetooth systems coexistence. A Bluetooth standard works in an unlicensed frequency band 2,402 – 2,480 GHz. This frequency band is also used by an IEEE 802.11b/g standard (Wi-Fi) which is the most extended representative of WLAN networks. Because Bluetooth and Wi-Fi systems operate in the same frequency band, a mutual signal degradation may appear, when devices are collocated in the same area. In the first part of the dissertation thesis there is a brief summary of 2,402 - 2,480 GHz frequency band regulations and its usage. There are described physical layers of Bluetooth and IEEE 802.11b/g standards and techniques used for a collision avoidance. The main part of the dissertation thesis deals with a development of a new Matlab Simulink model for investigations of the Bluetooth and Wi-Fi standards coexistence. Physical layer models and results of the coexistence simulations are verified by a measurement in real conditions with a help of a modern vector signal analyzer. The results are presented in a graphical form and a brief summary is attached at the end of each chapter. Corresponding tables of simulated and measured values are available in the enclosed CD.
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Monitoring interference in the mains supply
Jirčík, Zdeněk ; Kubánek, David (referee) ; Zeman, Václav (advisor)
This semester thesis describes design of electronic device adapted to monitoring of mains supply. Theoretical parts describes mains supply analysis, communication and management of files to memory. Next part is design electronics blocks and their cooperation. There are description of mains analyzer prototype and it’s parts and functions. Prototype was submitted to test measurement.
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Interference Optimization in Cellular Communication Systems
Kassem, Edward ; Marchevský, Stanislav (referee) ; Masopust, Jiří (referee) ; Blumenstein, Jiří (advisor)
Tato práce je rozdělena do šesti kapitol. První kapitola vysvětluje rozdíly mezi fyzickou vrstvou uplinků systémů LTE a LTE Advanced, zkoumá charakteristiky kanálu komunikace D2D v rámci sítě LTE Advanced, a navrhuje mechanismy optimalizace interferencí. Rovněž je v práci prezentována struktura softwarově definované rádiové platformy, která může být využita pro vyhodnocení rádiových kanálů. Druhá kapitola hodnotí a porovnává výkony uplinkové části fyzické vrstvy systému LTE a LTE Advanced. V prostředí MATLAB je implementována struktura LTE Advanced vysílače a přijímače se všemi stupni zpracování signálu. Generované signály obou výše uvedených systémů jsou přenášeny přes různé modely kanálu ITU-R. Byly používány různé techniky odhadu kanálů a detekce signálu pro obnovení vysílaného signálu. Výsledky jsou prezentovány formou křivek BER a křivek datové prostupnosti. Třetí kapitola navrhuje způsob opakování frekvencí v celulární síti (frequency-reuse) se třemi úrovněmi výkonu, který se využívá jako typ pokročilé metody snižování interferencí. Jsou ukázány normalizované kapacitní hustoty buněk a jejich podoblastí se třemi různými případy distribuce uživatelů uvnitř buněk. Je zobrazena korelace mezi celkovou kapacitou a poloměrem každého regionu. Dosažené výsledky navrhovaného schématu jsou porovnávány s tradiční technikou opakovaného použití frekvence (Reuse-3). Čtvrtá kapitola se zabývá výzkumem alternativní metody optimalizace interferencí. Bylo provedeno ověření kooperačních metod snímání rádiového spektra ve čtyřech různých reálných prostředích: venkovní-interiérové, vnitřní-venkovní, venkovní-vnitřní a venkovní-venkovní. Navržený systém je testován pomocí zařízení Universal Software Radio Peripheral (USRP) a obsahuje dva typy detektorů; energetický detektor a statistický detektor založený na Kolmogorově-Smirnovově testu, které byly implementovány na přijímací straně. Jedním z hlavních požadavků komunikace D2D je znalost charakteristik impulzních odezev rádiového kanálu. Pátá kapitola proto představuje metodu měření kanálu pomocí Zadoff-Chu sekvencí ve frekvenční oblasti jako alternativní techniku k měření kanálu v časové nebo frekvenční doméně. Pomocí navržené metody se základní charakteristiky kanálu, jako je časové rozšíření kanálu (RMS delay spread, mean excess delay), útlum šířením a koherenční šířka pásma extrahují v (až 20x) kratším čase ve srovnání s klasickou metodou měření kanálu ve frekvenční doméně. Jsou také zkoumány charakteristiky venkovních statických rádiových kanálů na vzdálenost několika kilometrů pro pásma UHF a SHF s ko-polarizovanou horizontální a vertikální konfigurací antény. Šestá kapitola uzavírá tezi a shrnuje závěry.
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Comparison of the effect of bisphenols on parental and differentiated H9c2 cells
Macáková, Barbora ; Jirkovský, Eduard (advisor) ; Macháček, Miloslav (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Barbora Macáková Supervisor: PharmDr. Eduard Jirkovský, Ph.D. Title of diploma thesis: Comparison of the effect of bisphenols on parental and differentiated H9c2 cells Bisphenol is compound largely found in products and environment around us. Its toxicity and danger for human health is still being studied, meanwhile direct influence of environmentally relevant doses was not discovered. These endocrine disruptors are affecting variousreceptorsin bodiesand effecton cardiovascularsystem isnotexcludedeither.The most extensively studied substance is BPA, which is gradually being replaced by its analogs, although these are not extensively researched to the same extent. In this work we focused on influence of bisphenol BP, M and S on differentiation of H9c2 cells, serving as a model with potential negative effects on heart development and its regeneration after damage. H9c2 cell line has an undifferentiated phenotype but can be easily directed towards differentiation under certain conditions Research was focused on impact of bisphenol on differentiated cells and its changes in the expression of selected differentiation markers (GATA4, Hand2, Tnnt2, Myog) (transcription factors). Set protocols were...
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