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Study of luminicsence properties of organic semicondustors
Koňák, Petr ; Horák, Michal (referee) ; Boušek, Jaroslav (advisor)
This document describes using organic semiconductors to the electroluminescence on thin layers. In introduction of this file there is analysis a the problem of organic semiconductors and it's using in today's world. Next, I want to describe work with the given samples, their chemical composition and also include results from the measuration of electroluminescence.
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Substituting circuit of an induction machine
Běloušek, Radim ; Cipín, Radoslav (referee) ; Patočka, Miroslav (advisor)
Although induction motors are the simplest and most working reliability machines, is the identification of the parameters of their substituting circuit very difficult. There is solved the identification of the parameters of the substituting circuit in the T-network and ? –network in this work. The work also includes the proposal of magnetic circuit of the induction motor, the calculation of magnetizing and leakage inductances and resistances of the machine. The conclusion of the work is devoted to the sensitivity analysis of current and torque characteristics of induction motor upon the change of the single parameters of the substituting circuit.
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Influence of breathe to baroreceptor reflex
Humpolík, Tomáš ; Janoušek, Oto (referee) ; Kolářová, Jana (advisor)
This Master's thesis deals with the influence of breathe to baroreceptor reflex. The first chapter is focused on measuring of blood pressure, in reference to later used method. In the second part is detailed analysis and explanation of term baroreflex, relationship between frequency spectra of systolic blood pressure, heart rate and breathing, mechanisms of regulation of blood pressure and heart rate variability. Third chapter deals with possible ways, how to analyze data, which are needed for estimation of baroreflex sensitivity, analyze of heart rate variability and estimation of power spectral density. Next parts of this thesis is paid attention to technical equipment and methods of acqusition of data, using this equipmnent. Part of this work is also software application, which makes possible from the recorded data estimate baroreflex sensitivity.
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Traction Drives with Asynchronous Motors
Běloušek, Josef ; Skala, Bohumil (referee) ; Richter, Aleš (referee) ; Patočka, Miroslav (advisor)
The first part of this work is devoted to the design of a traction asynchronous motor. The second part focuses on the developed method of the equivalent circuit parameters identification of the asynchronous motor in the form of -network. It is explained here that the equivalent circuit in the shape of a -network, alternatively of an inverse 'I-network, is exactly equivalent and fully-fledged to a T-network, although one of two stray inductances is formally missing. Furthermore, the relationships for the conversions of the T-network parameters to the -network parameters and back, and of the T-network to the inverse 'I-network and back are found. The third part deals with the calculation of the torque and the current characteristics of the asynchronous motor. A sensitive analysis of the torque characteristic is carried out on the individual parameters of the equivalent circuit of the asynchronous motor in the form of a -network and a method of the measurement by means of a flywheel is used for the torque characteristic measurement of the asynchronous motor. The fourth part focuses on the verification of the identified -network parameters in the Matlab-model of the traction drive.
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QRS detection using zero crossing counts
Kašák, Pavel ; Hrubeš, Jan (referee) ; Vítek, Martin (advisor)
This thesis is focusing on problems of detection of QRS complex. It includes basic description of ECG signal. It acquaints with common methods of searching QRS complex. Main attention is paid to detection based on zero crossing counts, which is realized by MATLAB program. This algorithm is then tested on CSE database, optimised and its efficiency is evaluated.
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Detection of QRS complexes in ECG signals
Zhorný, Lukáš ; Ronzhina, Marina (referee) ; Kozumplík, Jiří (advisor)
This thesis deals with the detection of QRS complexes from electrocardiograms using time-frequency analysis. Detection procedures are based on wavelet and Stockwell transform. The theoretical part describes the basics of electrocardiography, then introduces common approaches to time-frequency analysis, such as short-time Fourier transform (STFT), wavelet transform and Stockwell transform. These algorithms were tested on a set of electrograms from the MIT-BIH and CSE-MO1 arrhythmia database. For the CSE database worked best the method based on the wavelet transform with the filter bank Symlet4, with the resulting value of sensitivity 100 % and positive predictivity 99.86%. For the MIT database had the best performance the detector using the Stockwell transform with values of sensitivity 99.54% and positive predictivity 99.68%. The results were compared with the values of other authors mentioned in the text.
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Analog Signal Processing with Integrated Current Feedback Amplifiers
Ben Ayad, Ibrahim R. H. ; Mikula, Vladimír (referee) ; Šimčák, Marek (referee) ; Musil, Vladislav (advisor)
Tato disertační práce pojednává o návrhu nových funkčních bloků použitelných v oblasti zpracování analogového signálu. Jde o obvody v proudové módu, které mohou ve vhodné konfiguraci pracovat v proudovém i v napěťovém módu. To umožnílo získat velmi nadějné výsledky v soustavách s nízkým napájecím napětím. Mnohostrannost těchto obvodů nalezne uplatnění v mnoha aplikacích. Zesilovač s proudovou zpětnou vazbou byl zavolen jako hlavní stavební blok pro detailní zkoumání funkce obvodů s RC operační sítí. Tato disertační práce pojednává o studiu, syntéze a návrhových aspektech realizace nových imitančních funkcí, jmenovitě induktivních a superkapacitních, proudových a napěťových konvejorech, kmitočtových filtrech s velkou jakostí, integrátorech a diferenciátorech, fázovacích členech s neminimální fází a napětím řízených oscilátorech. Disertační práce se detailně zabývá těmito novými bloky, které jsou popsány teoreticky a vyhodnoceny na základě simulací vlastností.
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Sensitivity analysis in distributed-parameter systems
Kapusta, Ján ; Dostál, Tomáš (referee) ; Brančík, Lubomír (advisor)
The aim of this bachelor’s thesis was to familiarize with calculation of modified nodal analysis and its application in distributed-parameter systems. Realize evaluation of sensitivities with respect to a primary parameters R0,L0,C0,G0 and length l of transmission line. Then apply this technique on example in Matlab language using graphical user interface GUIDE. Selected technique is accelerated method based on efficient computation of matrix exponential function. The results are sensitivities of circuit values with respect to a primary parameters R0,L0,C0,G0 and length l of transmission line.
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Nonlinearity in the course of acqusition date in optical coherence tomography
Kadla, Jan ; Kolář, Radim (referee) ; Kuna, Zdeněk (advisor)
This bachelor thesis builds on my semestral work, thus provides a description of the problem of optical coherence tomography imaging system in terms of a brief historical development, structural parts and modifications. Previous work is supplemented by a more detailed description of data acquisition and especially signal processing. I present examples of the clinical and research application of this technology, and try to objectively refer to its advantages and disadvantages. Chapter dedicated to the description of a practical measurement explains selected data collection procedure and clarifies their following processing. At the end of the work are summarized the results achieved, including the considerations of potential errors during the measurement.
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Properties of ultrasound probes
Rusina, Michal ; Mézl, Martin (referee) ; Harabiš, Vratislav (advisor)
This master thesis deals with the measurement properties of ultrasound probes. Ultrasound probes and their parameters significantly affect the quality of the final image. Values of pa-rameters of the probes may change due to their use, because probes may be damaged and the final image may no longer be correct. For these reasons the measurements of parameters of probes are very important. In this master thesis there are described and implemented the possibility of measuring the spatial resolution, focal zone, the sensitivity of the probe and measuring the length of the dead zone. Two ultrasonic phantoms were used for measuring. In the practical part there was created the program called Mereni_parametru, which allows to determine the value of four parameters from captured images of the phantom. Further, there are listed and described measured values for five ultrasonic probes. Results for two of these probes are then compared with the parameters given by the manufacturers.
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