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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.
111

Analýza spánkového EEG / Human Sleep EEG Analysis

Sadovský, Petr January 2007 (has links)
This thesis deals with analysis and processing of the Sleep Electroencephalogram (EEG) signals. The scope of this thesis can be split into several areas. The first area is application of the Independent Component Analysis (ICA) method for EEG signal analysis. A model of EEG signal formation is proposed and conditions under which this model is valid are examined. It is shown that ICA can be used to remove non-deterministic artifacts contained in the EEG signals. The second area of interest is analysis of stationarity of the Sleep EEG signal. Methods to identify stationary signal segments and to analyze statistical properties of these stationary segments are presented. The third area of interest focuses on spectral analysis of the Sleep EEG signals. Analyses are performed that shows the processes that form particular parts of EEG signals spectrum. Also, random signals that are an integral part of the EEG signals analysis are performed. The last area of interest focuses on elimination of the transition processes that are caused by the filtering of the short EEG signal segments.
112

Rozšířená kvadraticky optimální identifikace a filtrace / Quadratically Optimal Augmented Identification and Filtration

Dokoupil, Jakub January 2012 (has links)
Simultaneous evaluation of the whole set of the model parameters of different orders together with an ability to track unmodeled dynamics are desired features in the tasks of parameter estimation. A technique handling with the factors produced by an augmented covariance (ACM) or information (AIM) matrices is considered to be an appropriate tool for designing multiple model estimation. This is where the name augmented identification (AI) by using the least-squares method was taken. The method AI attains numerical stability of the calculation of the conventional least squares method while in the same time, fully extracts information contained in the observation. In order to track time varying parameters can be found that all the information pertinent to recursive identification and thus to data driven forgetting is concentrated in ACM as well as in AIM. In this thesis will be introduced how to selective forgetting to ACM should be applied in an effective way. It means forget only a portion of accumulated information which will be further modified by the newest data included in the regressor. In the estimation problems the knowledge of the inner states of the identified system is often required. Because the augmented identification belongs within the class so called prediction error method (PEM), some rational requirements can be deduced. As a result, state filter should constitute optimization procedure minimizing the predicted error of given state space model representation with respect to the vector of states. The proposed scheme will considerably extend the family of algorithms based on processing of ACM (AIM) about augmented filtering (AF). This all will establish a comprehensive concept of parametric estimation that compared with conventional approaches is characterized by versatility, low demands on a priori process information and by excellent numerical properties (robust against overparametrization, capable solving the multiple model problem).
113

Vyhodnocení příbuznosti organismů pomocí číslicového zpracování genomických dat / Evaluation of Organisms Relationship by Genomic Signal Processing

Škutková, Helena January 2016 (has links)
This dissertation deals with alternative techniques for analysis of genetic information of organisms. The theoretical part presents two different approaches for evaluation of relationship between organisms based on mutual similarity of genetic information contained in their DNA sequences. The first approach is currently standardized phylogenetics analysis of character based records of DNA sequences. Although this approach is computationally expensive due to the need of multiple sequence alignment, it allows evaluation of global and local similarity of DNA sequences. The second approach is represented by techniques for classification of DNA sequences in a form of numerical vectors representing characteristic features of their genetic information. These methods known as „alignment free“ allow fast evaluation of global similarity but cannot evaluate local changes. The new method presented in this dissertation combines the advantages of both approaches. It utilizes numerical representation similar to 1D digital signal, i.e. representation that contains specific trend along x-axis. The experimental part of dissertation deals with design of a set of appropriate tools for genomic signal processing to allow evaluation mutual similarity of taxonomically specific trends. On the basis of the mutual similarity of genomic signals, the classification in the form of dendrogram is applied. It corresponds to phylogenetic trees used in standard phylogenetics.
114

Řádová analýza signálů / Order Analysis

Honc, Lukáš January 2016 (has links)
This master's thesis deals with order analysis. The first part of the thesis describes common methods for order analysis and methods for processing tacho and vibration signal. The second part contains a brief description of some open source tools for order analysis focusing on Sound and Vibration Measurement Suite (SVMS) package for LabVIEW by National Instruments company. The main purpose of the thesis has been designing and realization of own library for order analysis as a plugin for development tool LabVIEW. In the library, there are implemented methods for order analysis including basic functions for processing vibration and tacho signal. Their brief description with manual for its usage is in the third part of the thesis. In the last chapter, implemented functions are compared with those, which are implemented in SVMS by National Instruments, using both simulated and real data.
115

Analýza vad typu nekovových vměstků v odlitcích hlav motorů a návrh metod jejich odstranění / Analysis of non-metalic inclusions in motor heads castings and suggestion on their remove

Dratnal, Lukáš January 2016 (has links)
Improving the quality of metal castings for serial production of automotive industry, leading to improvements in the properties of casts and their lower costs. This publication analyzes the non-metallic inclusions contained in casts of heads of internal combustion engines, molded of Nemak Czech Republic, Ltd. Tackling includes analysis of size, shape, chemical composition and hardness of the specific non-metallic inclusions. The thesis describes the purity metal holding furnaces and proposals to eliminate inclusions from metal.
116

Acceleration Methods for Evolutionary Design of Digital Circuits / Acceleration Methods for Evolutionary Design of Digital Circuits

Vašíček, Zdeněk Unknown Date (has links)
Ačkoliv můžeme v literatuře nalézt řadu příkladů prezentujících evoluční návrh jakožto zajímavou a slibnou alternativu k tradičním návrhovým technikám používaným v oblasti číslicových obvodů, praktické nasazení je často problematické zejména v důsledku tzv. problému škálovatelnosti, který se projevuje např. tak, že evoluční algoritmus je schopen poskytovat uspokojivé výsledky pouze pro malé instance řešeného problému. Vážný problém představuje tzv. problém škálovatelnosti evaluace fitness funkce, který je markantní zejména v oblasti syntézy kombinačních obvodů, kde doba potřebná pro ohodnocení kandidátního řešení typicky roste exponenciálně se zvyšujícím se počtem primárních vstupů. Tato disertační práce se zabývá návrhem několika metod umožňujících redukovat problem škálovatelnosti evaluace v oblasti evolučního návrhu a optimalizace číslicových systémů. Cílem je pomocí několika případových studií ukázat, že s využitím vhodných akceleračních technik jsou evoluční techniky schopny automaticky navrhovat inovativní/kompetitivní řešení praktických problémů. Aby bylo možné redukovat problém škálovatelnosti v oblasti evolučního návrhu číslicových filtrů, byl navržen doménově specifický akcelerátor na bázi FPGA. Tato problematika reprezentuje případ, kdy je nutné ohodnotit velké množství trénovacích dat a současně provést mnoho generací. Pomocí navrženého akcelerátoru se podařilo objevit efektivní implementace různých nelineárních obrazových filtrů. S využitím evolučně navržených filtrů byl vytvořen robustní nelineární filtr implusního šumu, který je chráněn užitným vzorem. Navržený filtr vykazuje v porovnání s konvenčními řešeními vysokou kvalitu filtrace a nízkou implementační cenu. Spojením evolučního návrhu a technik známých z oblasti formální verifikace se podařilo vytvořit systém umožňující výrazně redukovat problém škálovatelnosti evoluční syntézy kombinačních obvodů na úrovni hradel. Navržená metoda dovoluje produkovat komplexní a přesto kvalitní řešení, která jsou schopna konkurovat komerčním nástrojům pro logickou syntézu. Navržený algoritmus byl experimentálně ověřen na sadě několika benchmarkových obvodů včetně tzv. obtížně syntetizovatelných obvodů, kde dosahoval v průměru o 25% lepších výsledků než dostupné akademické i komerční nástroje. Poslední doménou, kterou se práce zabývá, je akcelerace evolučního návrhu lineárních systémů. Na příkladu evolučního návrhu násobiček s vícenásobnými konstantními koeficienty bylo ukázáno, že čas potřebný k evaluaci kandidátního řešení lze výrazně redukovat (defacto na ohodocení jediného testovacího vektoru), je-li brán v potaz charakter řešeného problému (v tomto případě linearita).
117

Časový snímek z obrazu stacionární kamery / Time Lapse from Stationary Camera Image

Turek, Lukáš January 2015 (has links)
The topic of this master's thesis is the time lapse from stationary camera images. Unwanted phenomena, which arise in time lapse, were analyzed and algorithms to overcome these limitations were designed. The algorithms were implemented and compared using the captured dataset. The resulting application creates time lapse from the video input and allows users to choose the processing technique including the setting of appropriate parameters.
118

Výzkum, optimalizace a zavedení výroby těžkých odlitků z vysokolegovaných litin / Research, Optimization and Starting the Production of Heavy High-Alloy Cast Irons

Kaňa, Václav January 2012 (has links)
The work is particularly aimed at metallurgical problems connected with manufacture of castings of weight about 1 up to 40 tons from high-alloy austenitic nickel cast irons also known under the trade name Ni-resist. The main aim is to check and complement the knowledge about manufacture of heavy castings from austenitic nickel cast irons in a field of control of tapping and casting temperature, carbon content control with regard to the prediction of eutectic composition and in a field of setting a suitable chemical composition of cast iron with regard to the formation of chunky graphite and stability of the austenitic matrix and further on also possibilities of cast iron filtration during pouring the castings. Based on done experiments the formulae were determined that enable to calculate eutectic and liquidus temperatures on the basis of chemical composition of the cast iron. The use of several formulae given in the literature for calculating the carbon equivalent of austenitic nickel cast irons was compared and evaluated. For utilization of determined results in practice a calculating programme has been compiled making possible to be used in operational practice. This programme is named Calculation of casting temperature of Ni-resist cast irons. After the entry of the melt chemical composition the programme calculates the all important parameters necessary to know and to be controlled for manufacture of high quality castings from austenitic nickel cast irons. Eutectic temperature, liquidus temperature and then based on it the tapping and casting temperatures are included among those parameters. Further on there are eutectic concentration of carbon, carbon equivalent, nickel equivalent, and a criterion evaluating a danger of chunky graphite formation.
119

Určování poloh robotů Trilobot / Determination of Trilobot Robots Positions

Loyka, Tomáš January 2007 (has links)
This master's thesis is engaged in machine vision, methods of image processing and analysis. The reason is to create application to determine relative positions of Trilobot robots in the laboratory.
120

Topografické mapování skalních útvarů s využitím dat leteckého laserového skenování / Topographic mapping of rock formations with the use of airborne laser scanning data

Lysák, Jakub January 2016 (has links)
Abstract This thesis focuses on topographic mapping of rock formations with the use of new technologies in a comprehensive manner, from airborne laser scanning (ALS) data acquisition and processing in rocky terrains, followed by their processing to the content of topographic databases and their cartographic processing in maps. The introduction discusses issues of importance for practice, and the relation between topographic mapping of rocks and other fields of human activity. The ALS section describes products for topographic mapping of rocks derived from ALS data, and discusses the specifics of ALS data acquisition and processing in wooded rugged terrain. Existing solutions of this problem are explained and their limitations are identified. Author's own approaches to solving this task are presented as case studies, including three made a further three designed experiments with ALS data processing and evaluation of their results. Recommendation regarding mapping of sandstone landscapes in Czechia have been also addressed. The topographic section describes the current representation of rocks and related objects in the ZABAGED database (Czech national digital topographic database), explains the historical context, analyzes this data and identifies their shortcomings in relation to the ALS. Research...

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