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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Pohon EC motoru malého výkonu / Low power BLDC electric drive

Štajner, David January 2017 (has links)
The aim of this diploma thesis is to introduce a construction and controlling of the EC motor. On a base of knowledge make up a EC motor model in Matlab Simulink, with a position scanning providing by Hall probe. The EC motor model should be with its behavior close to the real EC motor as much as possible. There were a given requirements on the motor. On the base of those requirements was chosen a real EC motor. Its catalog values were put in the EC motor model in Matlab and the results were compared with real data. Next task was to design a real controlling driver of EC motor, which should has a minimal size. This driver was constructed and thermal test was made a on given load.
122

Strukturní a regulační aspekty aktivace kinázy Src / Structural and regulatory aspects of Src kinase activation

Koudelková, Lenka January 2020 (has links)
Src kinase plays a crucial role in a multitude of fundamental cellular processes. Src is an essential component of signalling pathways controlling cellular proliferation, motility or differentiation, and is often found deregulated in tumours. Src activity is therefore maintained under stringent and complex regulation mediated by SH3 and SH2 domains and the phosphorylation state of tyrosines 416 and 527. Active Src adopts an open conformation whereas inactive state of the kinase is characterised by a compact structure stabilised by inhibitory intramolecular interactions. We identified phosphorylation of tyrosine 90 within binding surface of SH3 domain as a new regulatory switch controlling Src kinase activation. Using substitutions mimicking phosphorylation state of the residue we demonstrated that tyrosine 90 phosphorylation controls Src catalytic activity, conformation and interactions mediated by the SH3 domain, representing a positive regulatory mechanism leading to elevated activation of mitogenic pathways and increased invasive potential of cells. Based on correlation between compactness of Src structure and its catalytic activity, we constructed a FRET-based sensor of Src conformation enabling to measure the dynamics of Src activation in cells with spatio-temporal resolution. We found that...
123

Grafické prostředí pro simulaci robotů / Graphical Environment for Robot Simulation

Malina, Michal January 2008 (has links)
This thesis deals with robot modelling and simulation of the robot behavior. At first we discuss a benefit of this kind of simulation. Next we describe the general scheme of robot. After that we select the environment where robot will be simulated in. There is a conception of this robot and explanation of the implementation in chosen environment. We continue with design and realization of the communication interface of this robot. The result of this procedure is robot with independent movement able to response to the obstructions and avoid them. Robot is able to create a map of the environment and use this map to find out the optimal way to the scheduled goal using the A* algorithm and achieve this goal. There is a possibility to use more robots in the scene. These communicate and the nearest one is able to get the goal.
124

Study of Electric and Dielectric Properties of Ionic Liquids / Study of Electric and Dielectric Properties of Ionic Liquids

Altšmíd, Jakub January 2019 (has links)
Dizertační práce je zaměřena na studium elektrických a dielektrických vlastností iontových kapalin. Iontové kapaliny mohou nacházet uplatnění v široké škále aplikací, především pak v elektrotechnice. Teoretická část se věnuje popisu základních vlastností iontových kapalin a možností jejich uplatnění v kondenzátorech a elektrochemických senzorech plynů. Experimentální část se věnuje použitým metodám charakterizace vlastností iontových kapalin, jsou zde popsány teoretické poznatky o dielektrické spektroskopii včetně metod stanovení fyzikálních vlastností a vyhodnocení experimentálních dat. Experimentální část je rozdělena na dvě základní části. První se věnuje studiu iontových kapalin pro použití jako elektrolytu v kondenzátorech, druhá část se věnuje studiu vlastností připravených experimentálních senzorů na NO2, zejména vlivem vlastností iontových kapalin na sledované parametry senzoru.
125

Porovnání použití přístrojových transformátorů a senzorů v aplikacích s ochranou REF 542plus / Comparison of Instrument Transformer and Sensor Applications in Feeder Terminal REF 542plus

Hrycík, Tomáš January 2010 (has links)
The aim of this Master´s thesis is use of instrument transformers and sensors on field of industry protection. We will compare current and voltage transformers, current sensor – based on Rogowski coil, voltage sensor – based on voltage divider. By this measure devices, we can monitoring values of analog quantities in medium voltage switchgear. It is impossible to compare, measure and analyze without this measure devices. There is protection terminal REF542plus, which can compile this values. The REF542plus ability are measuring, monitoring, remote control and protection. First, we will discuss about theory of sensors and convential instrument transformers and analysis of analog signal. We will compare analog input channel on sensor´s analog module and transformer´s analog module. There are few differences between type of analog modules. For analog signal analysis are important frequency filters and Analog/ Digital Convertor (sigma-delta). We will describe functions and options of REF542plus. In practical part of this project, we will test protection functions of protection terminal. First, protection terminal will be connected to sensors. Second protection terminal will be connected to transformers. For testing we chose Earth-fault directional protection and differential protection. We will make only secondary tests. That´s mean, input analog quantities to REF542plus will be simulated by tester. In all we will verify quality of protection. We will focus on lower settings of protection and we will inject protection by low current. Objectives are testing of trip characteristics and measuring of trip time.
126

Magnetické nanostruktury pro optické senzory / Magnetic nanostructures for recording and optical sensors

Lišková, Eva January 2011 (has links)
Title: Magnetic nanostructures for recording and optical sensors Author: Eva Lišková Department: Institute of Physics, Charles University Supervisor: Prof. Ing. Štefan Višňovský, DrSc. Abstract: Magneto-optical (MO) spectra of multilayered structures with enhanced MO effect were studied using the polar and longitudinal Kerr spectroscopy with oblique angle of light incidence in the photon energy range 1.2 eV to 5 eV. The samples with Fabry- Perot cavity like architecture, were modeled using Yeh matrix formalism. Two sets of samples, with composition FeF2/Fe/FeF2 and AlN/Fe/AlN, were prepared by molecular beam epitaxy and sputtering. The relations were studied between the position of the enhanced peak in the MO spectra and the structure. Second part of this work was devoted to the Pt/Co/Pt structures and the influence of the ion implantation on MO spectra and structural composition. The studied multilayer structures present interest for MO sensor and memory applications. Keywords: Magneto-optical Kerr effect, Magneto-optical sensor, Fabry-Perot resonator, Ion implantation
127

Distribuované optické vláknové senzory / Distributed fiber optic sensors

Holík, Tomáš January 2018 (has links)
The thesis deals with the possibility of using optical fiber as a sensor. The introduction of the thesis is devoted to the foundations of optics. In addition, the thesis deals with optical interferometry, polarization and dispersion in optical fiber. The main output of the thesis is the comparison of acoustic vibration measurements using interferometric and polarization methods and further measurements on the real route in Brno.
128

Podélné indexové struktury v optických vláknech / Longitudinal index structures in optical fibers

Polreich, Štěpán January 2018 (has links)
This thesis describes basic concepts, principles and properties of optical fibers. Considerable part is devoted to fiber gratings that are created by a change in the refractive index in the optical fiber core. In this work is described description, principle, method od production and distribution of gratings on Bragg gratings, gratings with long period and chirped gratings. In this thesis are also presented different types of lasers and their advantages over other lasers. A large part deals with the description of the femtosecond laser, with which the structures will be later made into the material. In addition, the laser modes are differentiated, this is a mode of micro-machining and modification or a change in refractive index of the material. The last part deals with change the refractive index in planar technology, the creation of a groove for fastening the fiber and attempts to write the gratings into the optical fiber. Created fiber sensor are tested for temperature and tensile changes. Finally, the practical use of sensors made by femtosecond laser and the advantages over UV laser and phase mask techniques are presented.
129

Návrh nového iontmetru s bezdrátovou komunikací a meteostanicí / Design of a new iontometer with wireless communication and weather station

Kadlček, Václav January 2018 (has links)
This diploma thesis deals with the design of an autonomous system for the measurement of the concentration of atmospheric ions. This is a new version of the already asembled Iontmeter by UTEE FEKT. Unlike the previous version, this new one should be completely independent of electrical network and configurable even without a PC. The design includes increased water and dust resistance, wireless transmission from the weather station and its own temperature, atmospheric pressure and relative humidity sensor.
130

Analýza dat pro řešení problémů s vlhkostí v budovách / Analysis of Data to Solve Problems with Humidity in Buildings

Nečasová, Klára January 2019 (has links)
The aim of this work was to solve problems with excessive humidity in buildings using data analysis. The theoretical part of the work deals with impacts of excessive humidity on the health of building occupants and also the condition of the building structure. Data mining methods including classification, prediction, and clustering are described together with model evaluation and selection. The practical part focuses on hardware platform description and measurement scenarios. Key parameters affecting indoor relative humidity are indoor and outdoor temperature and outdoor relative humidity. The long-term measurement of the mentioned parameters was performed using the set of sensors and BeeeOn system. Measured data was used to design a system for event detection related to a humidity change. The approach to air change regulation in the room was based on natural ventilation.

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