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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.
1

Michelsonův interferometr / Michelson's interferometer

Rýc, Jan January 2011 (has links)
The diploma work deals with techniques of optical contactless distance and velocity measurement. A basic summary of the methods are involved. The problematic of interferometric methods for vibration measurements is analysed in detail. It contains division of interferometers, description of their function principles and also chapters dealing with elements used in interferometers such as lasers, photodetectors and elements in the ray optical way - polarizers, retarders, optical isolators. The vibration and length measurement methods are described, as well as the conception of homodyne and heterodyne detection. Part of this work focuses on the quadrature signal processing and on the proposal of algorithm for demodulation of velocity/displacement and undergoing simple motioning object deviation. This algorithm is implemented in Labview and the whole software instrument served also for visualisation of measured data of the interferometer model constructed in the laboratory. The way how to build up a model, its setting and two possible configurations suitable for homodyne detection are described. Model of interferometer is built-up on the optical breadboard. Particular components are fixed by the help of mounts. The model and software enable to measure the velocity and the vibration deviation with the light wavelength exactness. Functionality and the exactness of the laboratory model are verified by vibrometer. Effects on the measurement uncertainty are discussed here and ways how to restrain them are proposed.
2

Měřicí zesilovač využívající vektorové synchronní detekce / Vector phase-sensitive measurement amplifier

Rejnuš, Milan January 2014 (has links)
The master’s thesis describes known methods of signal measurement using principle of synchronous detection. Various methods are presented, their principles are examined and the problems when using them are analyzed. Further, procedures for reduction of adverse effects are described also. Second part of this thesis is focused on the instrument design. The instrument is intended for detection and processing of the output signals in a given optometric system. The proposed device is designed to operate on the principle of synchronous detection method using a vector signal evaluation. Advantages and disadvantages are discussed below.
3

Ultrazvukový měřič rychlosti toku krve / Ultrasonic blood flow meter

Pavlík, Dušan January 2011 (has links)
This thesis deals with ultrasound blood flow meter design with emphasis on practical implementation of such device. This medical device is used in ultrasound diagnostic, especially for measuring direction and velocity of blood flow in superficial vessels. This thesis contains consecutive design including description of individual function blocks. Documents for making double-sided printed circuit are included as well.
4

Kvadraturní zrcadlové banky filtrů se sigma-delta modulátory / Quadrature Mirror Digital Filtr Banks with Sigma-delta Modulators

Vrána, Jaroslav January 2008 (has links)
Dissertation thesis is focused on real digital signal processing by quadrature mirror digital filter banks. In the first part a dual channel quadrature mirror digital filter bank is described briefly. Mainly transfer functions for distorted subband signals are described. In the next part generalized sigma-delta modulator and its linear model are described. Subsequently the generalized sigma-delta modulator is used in decomposition part of quadrature mirror digital filter bank. Designed structure is analyzed. Two design method of transfer functions are designed for the structure on the basis of analysis results. The first method is suitable for hand-made design by intuitive distribution of zeros and poles. The second method is more suitable for computer design. It is iterative method based on correlation. Transfer functions for quadrature mirror digital filter bank with sigma-delta modulators design examples are also part of thesis. Application of designed structure of quadrature mirror digital filter bank can lead to bigger compression ration in lossy data compression.
5

Modul pro verifikaci rotačních pozičních senzorů / Module for verification of rotational position sensors

Krolák, David January 2016 (has links)
This master‘s thesis deals with design and realisation of a control module for automated measurements of the modern contactless inductive position sensors by a mechanical rotational system consisting of a DC motor and an incremental quadrature encoder. The thesis presents methods of driving DC motor and recording of measured data by a microcontroller. The thesis presents a communication protocol between the control module and personal computer via USB interface. A part of this thesis is also to develop a control software and firmware, including the measurement and evaluation of properties of the control module.
6

Mikroprocesorový modul řízení SS motoru se zpětnou vazbou / DC motor controler with feedback

Dundáček, Martin January 2008 (has links)
This thesis deals with DC motor control. Main goal was design and realization of DC motor controler module with feedback. The first part dwells on methods for DC motor control and HW design of control module. The second part describes development of software for the module, testing and sums up results.
7

Studium elektronického řízení a reálného chování variabilních filtračních a oscilačních aplikací moderních aktivních prvků / Study of Electronic Control and Real Behavior in Variable Filtering and Oscillating Applications of Modern Active Elements

Šotner, Roman January 2012 (has links)
The thesis deals with electronically adjustable and configurable applications of the modern active elements. In the field there were presented various active elements in applications of the analog filters and oscillators which stem from basic and more or less similar principles of circuit synthesis and design. However, there is not provided study of real behavior in detail and in most cases electronic control of the various parameters in application is not verified. In the precise design of application is very important to identify problematic features and determine how much it influences functionality of the device. In this work several filtering structures based on common and modified synthesis principles (integrator loops) are compared in the view of multifunctionality, configurability, variability, kind of used electronic control and impact of influences of real elements on behavior. There are used standard methods like adjusting of variable transconductance, intrinsic value of current input resistance and not so common method based on variable current gain in design of modified and improved multifunctional filtering circuits. The last method of mentioned control enabled to find quite unique filter which allows continuous electronic change of transfer from band-reject to all-pass filter of the 2nd order without reconnection. It is much simpler than previous and more common integrator loops. Larger part of this work is focused on electronically controllable oscillators mainly on quadrature types. There is presented several very simply and elementary realizations which require minimal number of active and passive elements. There are also slightly or more complicated solutions which remove some drawbacks of mentioned simpler variants. First of all there is given attention on study of real behavior which make obvious different problems with mutual dependence of oscillation condition and oscillation frequency, dependence of produced amplitudes (quadrature types) on parameter which is controlling oscillation frequency, influence of this parameter on oscillation condition, etc. In the framework of this part of the thesis there was introduced a novel modification of current conveyor transconductance amplifier (CCTA) so called current-gain-controlled current conveyor transconductance amplifier (CGCCCTA). Requirements for novel applications in the field of oscillators for newly developed controllable current amplifier and digitally controllable current amplifier (DACA) at the Department of Telecommunication FEEC BUT lead to creation of several chapters of this work where mentioned active elements can be used. The important contribution of this work (for practical approach) is also experimental testing of most of designed circuits and determination of exact design equations and rules which take into account real behavior of circuits and confirm results obtained from experiments.
8

Obvody pro analogové zpracování signálů na bázi nekonvenčních aktivních prvků / Circuits for Analog Signal Processing Employing Unconventional Active Elements

Khatib, Nabhan January 2013 (has links)
Disertační práce se zabývá zaváděním nových struktur moderních aktivních prvků pracujících v napěťovém, proudovém a smíšeném režimu. Funkčnost a chování těchto prvků byly ověřeny prostřednictvím SPICE simulací. V této práci je zahrnuta řada simulací, které dokazují přesnost a dobré vlastnosti těchto prvků, přičemž velký důraz byl kladen na to, aby tyto prvky byly schopny pracovat při nízkém napájecím napětí, jelikož poptávka po přenosných elektronických zařízeních a implantabilních zdravotnických přístrojích stále roste. Tyto přístroje jsou napájeny bateriemi a k tomu, aby byla prodloužena jejich životnost, trend navrhování analogových obvodů směřuje k stále většímu snižování spotřeby a napájecího napětí. Hlavním přínosem této práce je návrh nových CMOS struktur: CCII (Current Conveyor Second Generation) na základě BD (Bulk Driven), FG (Floating Gate) a QFG (Quasi Floating Gate); DVCC (Differential Voltage Current Conveyor) na základě FG, transkonduktor na základě nové techniky BD_QFG (Bulk Driven_Quasi Floating Gate), CCCDBA (Current Controlled Current Differencing Buffered Amplifier) na základě GD (Gate Driven), VDBA (Voltage Differencing Buffered Amplifier) na základě GD a DBeTA (Differential_Input Buffered and External Transconductance Amplifier) na základě BD. Dále je uvedeno několik zajímavých aplikací užívajících výše jmenované prvky. Získané výsledky simulací odpovídají teoretickým předpokladům.
9

Antonio Campi (1523-1587). Mezi manýrou a barokem. / Antonio Campi (1523-1587). Between Mannerism and Baroque.

Hlušičková, Pavla January 2015 (has links)
The dissertation evaluated the formal, stylistic and contextual analysis of the painting oeuvre of the Cremonese native Antonio Campi. Monographic elaboration of Campi's oeuvre complement to the existing range of syntheses a number of information that has been in the literature so far omitted. The work assessed Antonio's oeuvre on the revision of archival material preserved in Milanese and Cremonese state and church archives, as well as by the means of thorough study of the secondary literature. Chronology of Campi's production was based on the stylistic and formal analysis and at the same time it has been enriched by a number of comparisons of the Lombardy-Ligurian region. Perspective at Antonio's oeuvre was accompanied by drawings and panel paintings that have emerged in the art market in recent years. With this thorough analysis, it became clear that the simple definition of an older Italian scientific literature that had Antonio Campi understood as a painter, who by his work formed the basis of Caravaggio chiaroscuro approach in the last decades of the 16th century and in the early years of the 17th age, proved to be inaccurate. It became clear that with this view we can not identify ourselves any more. Constant changes in mood, surprise, unpredictability, restlessness and individuality, the...
10

Nové aktivní funkční bloky a jejich aplikace v kmitočtových filtrech a kvadraturních oscilátorech / Novel active function blocks and their applications in frequency filters and quadrature oscillators

Herencsár, Norbert January 2010 (has links)
Kmitočtové filtry a sinusoidní oscilátory jsou lineární elektronické obvody, které jsou používány v široké oblasti elektroniky a jsou základními stavebními bloky v analogovém zpracování signálu. V poslední dekádě pro tento účel bylo prezentováno velké množství stavebních funkčních bloků. V letech 2000 a 2006 na Ústavu telekomunikací, VUT v Brně byly definovány univerzální proudový konvejor (UCC) a univerzální napět'ový konvejor (UVC) a vyrobeny ve spolupráci s firmou AMI Semiconductor Czech, Ltd. Ovšem, stále existuje požadavek na vývoj nových aktivních prvků, které nabízejí nové výhody. Hlavní přínos práce proto spočívá v definici dalších původních aktivních stavebních bloků jako jsou differential-input buffered and transconductance amplifier (DBTA), current follower transconductance amplifier (CFTA), z-copy current-controlled current inverting transconductance amplifier (ZC-CCCITA), generalized current follower differential input transconductance amplifier (GCFDITA), voltage gain-controlled modified current-feedback operational amplifier (VGC-MCFOA), a minus-type current-controlled third-generation voltage conveyor (CC-VCIII-). Pomocí navržených aktivních stavebních bloků byly prezentovány původní zapojení fázovacích článků prvního řádu, univerzální filtry druhého řádu, ekvivalenty obvodu typu KHN, inverzní filtry, aktivní simulátory uzemněného induktoru a kvadraturní sinusoidní oscilátory pracující v proudovém, napět'ovém a smíšeném módu. Chování navržených obvodů byla ověřena simulací v prostředí SPICE a ve vybraných případech experimentálním měřením.

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