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Prise en compte des incertitudes dimensionnelles introduites par les procédés de fabrication dans les modèles numériques de machines électriques / Consideration of dimensional uncertainties introduced by the manufacturing processes in the numeric models of the electrical machinesLiu, Sijun 23 November 2015 (has links)
Les procédés de fabrication, du fait de leurs imperfections, conduisent à des dispersions des dimensions par rapport au nominal ainsi qu’à une variabilité de celles-ci d’un produit à un autre. Pour les machines électriques, ces imperfections peuvent conduire à des excentricités entre le rotor et le stator ou à des déformations de la surface intérieure du stator (défaut de forme). Dans la littérature, les travaux se focalisent surtout sur l’étude des effets néfastes dus à l’excentricité et pas sur les défauts de forme. De plus, ces travaux sont souvent basés sur une approche déterministe négligeant la variabilité qui peut apparaitre dans le cas de la production de masse. L’objectif de la thèse est donc de mettre en place une méthodologie basée sur une approche probabiliste permettant de quantifier l’effet des imperfections des procédés de fabrication sur la géométrie d’une machine électrique et d’en évaluer l’impact sur les performances. Pour cela, une campagne de mesures dimensionnelles a été effectuée sur 50 machines électriques permettant de caractériser les principaux défauts comme l’excentricité et la déformation de la surface intérieure du stator. Des modèles probabilistes de ces défauts ont été proposés permettant de prendre en compte leur variabilité. L’utilisation d’un modèle numérique de la machine électrique combiné avec des techniques d’approximation creuse ont permis d’évaluer l’influence de ces défauts sur les grandeurs d’intérêt comme la FEM ou le couple. / Due to their imperfections, manufacturing processes lead to deviations on the dimensions which are not equal to their nominal value and as well as a variability on the dimensions from one product to another in the case of mass production. For electrical machines, these imperfections can cause an eccentricity between the rotor and the stator or shape default like the deformation of the inner surface of the stator. In the literature, research focuses mainly on the study of detrimental effects due to the eccentricity but not on shape default. In addition, this research is often based on a deterministic approach neglecting the variability that can arise especially in mass production. The aim of the thesis is to develop a methodology based on a probabilistic approach to quantify on the performances of an electrical machine the effect of imperfections of manufacturing processes on the geometry. First, a campaign of measurements was performed on 50 electrical machines for characterizing the main defaults such as the eccentricity and the deformation of the inner surface of the stator. Probabilistic models of these defaults have been proposed for taking into account their variability. A numerical model of the electrical machine combined with sparse approximation techniques were used to quantify the influence of these defaults on quantities of interest such as EMF or torque.
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Sledování vlivu expozice elektromagnetickým polem na kolonii kvasinek / Monitoring the impact of exposure to electromagnetic fields in yeast coloniesHájková, Renata January 2011 (has links)
Identifikační záznam: HÁJKOVÁ, Renata. Sledování vlivu expozice elektromagnetickým polem na kolonii kvasinek [Monitoring the impact of exposure to electromagnetic fields in yeast colonies]. Praha, 2011, rok vydání. 74s., 2. příl. Diplomová práce (Mgr.). Univerzita Karlova v Praze, 1. Lékařská fakulta, Fakulta elektrotechnická, Katedra elektromagnetického pole, ČVUT v Praze. Vedoucí závěrečné práce Vorlíček, Jaroslav, Ing. Abstract: Current development of mobile telecommunication device increases interest of public to the question of influence of electromagnetic field to the living organisms. Results of this work contribute to better knowledge of interaction between electromagnetic field and cell structures. Beginning of the thesis is review of morphology and physiology of the yeast cell that was used in this work as a tested organism. Second chapter describe the basic facts about electromagnetic fiend and wireless energy transfer. Goal of the practical part of this master thesis is describe influence of electromagnetic field on population of yeast during their proliferation. We constructed special box connected with wireless energy generator that was source of exactly defined electromagnetic field. Cells of Saccharomyces cerevisiae were diluted in fluid medium YPD and the proliferation of the culture was...
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Tommy Wieringa jakožto autor (pro) 21. století: spisovatel uvnitř a vně literárního provozu / Tommy Wieringa as a 21st century author: the writer within and outside the publishing sphereVítek, Lukáš January 2017 (has links)
(English) The aim of this master thesis is to analyse the fiction of Tommy Wieringa, specifically in relation to the concept of the posture developed by Jérôme Meizoz. The distinction between the internal posture and the external posture is essential in this theory. Therefore, there can arise a tension between both images of the author (i.e., in the terminology of Daniël Rovers, between auteursfiguur and figuurauteur). This thesis is based on the question if this statement is valid in case of the work of Wieringa. Keywords: Wieringa, author's posture, author's image, literary identity, self-fashioning, authorship, the literary field
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Pravidla hry: kritické hry a teorie na poli mezinárodních vztahů / Rules of the Game: Critical Games and Critical Theories of International RelationsFormánek, Václav January 2010 (has links)
The main goal od critical theories of international relations is to help to achieve more universal freedom and equality in the world. Critical theorists use different kinds of strategies to achieve this goal. Persuasive popularization by critical videogames is one those strategies. Author analyzes different strategies of such persuasion. He also designs own concept of critical game. The goal of this game is to present main ideas of critical theories to the general public in the most precise but still understandable way. Autor wants to show the potential of videogames for popularization of critical theories.
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Kompaktní formy bydlení v Brně, Černá Pole / High-density, Low-rise housing in Brno, Černá PoleJaník, Tobiáš January 2017 (has links)
Subject of my diploma thesis is to design new residential neighborhood on sight currently occupied by Barracks in Brno, Černá Pole. It is little used in the moment and forms spacial barrier in city organism and is slowly detracting. New proposal integrates area into surrounding development and is trying to maximally utilize its positive aspects. On site is not proposed just quiet residential neighborhood, but also city hall, shops, college dorm, primary school and kindergarten, creating a balanced unit communicating with the surrounding area.
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Microphone Arrays for Speaker Recognition / Microphone Arrays for Speaker RecognitionMošner, Ladislav January 2017 (has links)
Tato diplomová práce se zabývá problematikou vzdáleného rozpoznávání mluvčích. V případě dat zachycených odlehlým mikrofonem se přesnost standardního rozpoznávání značně snižuje, proto jsem navrhl dva přístupy pro zlepšení výsledků. Prvním z nich je použití mikrofonního pole (záměrně rozestavené sady mikrofonů), které je schopné nasměrovat virtuální "paprsek" na pozici řečníka. Dále jsem prováděl adaptaci komponent systému (PLDA skórování a extraktoru i-vektorů). S využitím simulace pokojových podmínek jsem syntetizoval trénovací a testovací data ze standardní datové sady NIST 2010. Ukázal jsem, že obě techniky a jejich kombinace vedou k výraznému zlepšení výsledků. Dále jsem se zabýval společným určením identity a pozice mluvčího. Zatímco výsledky ve venkovním simulovaném prostředí (bez ozvěn) jsou slibné, výsledky z interiéru (s ozvěnami) jsou smíšené a vyžadují další prozkoumání. Na závěr jsem mohl systémem vyhodnotit omezené množství reálných dat získaných přehráním a záznamem nahrávek ve skutečné místnosti. Zatímco výsledky pro mužské nahrávky odpovídají simulaci, výsledky pro ženské nahrávky nejsou přesvědčivé a vyžadují další analýzu.
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Návrh gaussmetru s tříosou měřicí sondou / Gaussmeter design with three-axis measuring probeHejtmánek, Tomáš January 2018 (has links)
The purpose of this work is the design of a gaussmeter with a three-axis probe for magnetic field mapping and subsequent reconstruction of the image using magnetic impedance tomography. Commercially available gaussmeters have low bandwidth for these purposes, and signals cannot be measured in synchronous detection mode. The aim of the thesis is select the most suitable magnetic field sensors for the MIT purposes and to design the entire measuring device to meet the measurement requirements in the wider frequency band and synchronous detection. Attention will also be paid to designing a suitable mechanical design of the probe and the location of the sensors. The proposed device will be tested and evaluated for MIT purposes.
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Model víceotáčkového motoru a simulace v programu ANSYS Maxwell / FEM model and simulation of induction motor with pole-changing windingZáškodný, Jiří January 2018 (has links)
This master thesis deals with calculations and simulations of multi-speed induction motors. In the first part, basic principle of these machines is described. Next, there are given three examples of pole-changing stator windings and their properties are analyzed (winding factors, magnetomotive force). Main part includes simulations and measuring of the specific motor, which is produced by company Siemens Mohelnice. This is the motor with 2/1 pole-changing in Y/YY connection. First, influence of skewed rotor slots on current and torque is analyzed. Next, parametres of motor from simulations are given and these results are compared to measured values.
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Optimalizace návrhu solárního kolektoru využívající latentní teplo fázové přeměny / Optimal design of solar air collector with latent heat thermal energy storageZálešák, Martin January 2018 (has links)
The thesis deals with the creation for a numerical model of a solar collector with a phase change material as a heat storage medium. The model was implemented in Python. Using the created model, design optimization of several problems was carried out with the use of selected methods of heuristic optimization. The results of the behaviour of the created model and of design optimization were then analysed and evaluated.
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Výpočtové modelování šíření hlasu okolo hlavy člověka pomocí metody konečných prvků / Computational modelling of voice propagation around the human head using finite element methodRyšavý, Antonín January 2018 (has links)
In the first part of this master's thesis there is briefly presented the biomechanics of the human voice creation and an overview of the hitherto published computational models of the vocal tract and dissemination of the acoustic waves around the human head. The second part of the thesis deals with the creation of the computational model of a dissemination of the acoustic waves through vocal tract and further into a space around the head during the pronouncing of the Czech vowel /a:/. The vocal tract is excited by a harmonic signal in the place of vocal chords. On the surface of the vocal tract and the part of the head including hair and skin there is defined an acoustic absorption. The dissemination of the acoustic waves in the vocal tract, in the near field around the mouth, in the area around the head and in the points on the cheeks is detailed mapped. The dissemination of the acoustic waves is analyzed in the points where the speech microphones are placed. Acoustic pressure dependence on frequency, transmission functions between defined points and the acoustic pressure amplitudes depending on the distance from the mouth are obtained. In particular, the frequency distortion of the spectra is observed at the points indicated. Furthermore, the radiation impedance in the mouth area is evaluated. The results obtained are compared with the results of the hitherto published experimental measurements and can be used for the exact measurement of human voice or for the frequency correction of the microphones during the scann of the speech and sing placced in the analyzed points.
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