923 research outputs found
Heuristic model in joint EEG-fMRI analysis
This work deals with the joint EEG-fMRI analysis based on the heuristic model. There is described principle of the heuristic model which assumes that the BOLD (blood oxygen level depend) signal measured by fMRI (functional magnetic resonance imaging) is directly proportional to the spectral shift in the EEG signal. The paper describes algorithm of calculations which was implemented and tested on real data from 22 subjects. The study also monitors effect of different EEG information selection from electrodes of interest (averaging or principal component analysis)
Design of frequency filters by the method of autonomous circuit with multi-port current-controlled current sources
Cílem práce je prostudovat principy řiditelných kmitočtových filtrů v proudovém módu. V práci jsou shrnuty obecné vlastnosti proudových prvků. Práce se zaměřuje především na prvek GCMI a jeho použití v kmitočtovém multifunkčním filtru v proudovém módu. Filtr je navržen autonomní metodou. Filtr je zde simulován s aktivními prvky OPA860 a AD844. Nakonec je v této práci multifunkční filtr praktický realizován v provedení s aktivním prvkem OPA860.The aim is to study the principles of controllable frequency current-mode filters. The paper summarizes the general characteristics of current elements. The work focuses on the element GCMI and its use in multi frequency current-mode filters. The filter is designed autonomous method. The filter is simulated with active elements of the OPA860 and AD844. Finally, in this work is multi-filter is implemented in a practical implementation of the active element OPA860.
Control and data structures in programming languages
Podstatou této práce je uvést základní informace o algoritmizaci a obecné poznatky o řídicích a datových strukturách. Tyto poznatky jsou pak ve vybraných programovacích jazycích konkretizovány, je provedeno jejich srovnání a na základě konkrétních zákonitostí jsou uvedeny příklady využití.The essence of this work is to give basic information about the algorithm development and general pieces of knowledge of the structures in programming languages. These pieces of knowledge are specified for selected programming languages, to comparison is performed and application examples based on specific patterns for corresponding language are presented.
Joint EEG-fMRI analysis based on heuristic model
Diplomová práce se zabývá sdruženou EEG-fMRI analýzou na základě heuristického modelu. Heuristický model popisuje vztah mezi změnami v prokrvení aktivních mozkových oblastí a v elektrické aktivitě neuronů. Dále se tato práce zabývá různými metodami extrakce užitečné informace z EEG záznamu a jejich vlivy na konečný výsledek sdružené analýzy. Byly testovány metody průměrování elektrod zájmu, rozklad pomocí analýzy hlavních komponent a rozklad pomocí nezávislých komponent. Metoda průměrování elektrod zájmu a rozklad pomocí PCA dává podobné výsledky, ale není možné z EEG záznamu extrahovat jedinečnou informaci o určitém stimulačním vektoru. Pomocí ICA rozkladu jsme schopni získat informaci vztahující se k určité stimulaci, ale nastává zde problém v konečné interpretaci a výběru správné komponenty při slepém hledání variability spřažené s experimentem. Bylo zjištěno, že ačkoliv komponenty vypočtené z časové posloupnosti EEG záznamu jsou vzájemně nezávislé, jejich posun spektra vzájemně koreluje. Tato spektrální závislost byla eliminována PCA/ICA rozkladem až na vektorech posunu spektra. Zde již každá komponenta přináší novou informaci o mozkové aktivitě. Výsledky z heuristického přístupu byly porovnávány s výsledky sdružené analýzy na základě výpočtu relativního a absolutního výkonu v pásmech zájmu a byly nalezeny souvislosti mezi aktivačními mapami, a to především mezi heuristickým modelem a relativním výkonem v pásmu gamma (20-40 Hz).The master thesis deals with the joint EEG-fMRI analysis based on a heuristic model that describes the relationship between changes in blood flow in active brain areas and in the electrical activity of neurons. This work also discusses various methods of extracting of useful information from the EEG and their influence on the final result of joined analysis. There were tested averaging methods of electrodes interest, decomposition by principal components analysis and decomposition by independent component analysis. Methods of averaging and decomposition by PCA give similar results, but information about a stimulus vector can not be extracted. Using ICA decomposition, we are able to obtain information relating to the certain stimulation, but there is the problem in the final interpretation and selection of the right components in a blind search for variability coupled with the experiment. It was found out that although components calculated from the time sequence EEG are independent for each to other, their spectrum shifts are correlated. This spectral dependence was eliminated by PCA / ICA decomposition from vectors of spectrum shifts. For this method, each component brings new information about brain activity. The results of the heuristic approach were compared with the results of the joined analysis based on the relative and absolute power approach from frequency bands of interest. And the similarity between activation maps was founded, especially for the heuristic model and the relative power from the gamma band (20-40Hz).
Web Traffic Data Export to MAFF
Cílem této bakalářské práce bylo seznámení se s principy přenosu, uložení a opětovného zobrazení webového provozu. Další částí byl návrh a realizace modulu pro rekonstrukci a exportování obsahu webového provozu. Tento modul umožňuje poskládat webové stránky získané ze zachycené webové komunikace. Rovněž umožňuje takové stránky zobrazit. Výstupy modulu jsou tvořeny pomocí archivačního formátu MAFF, který slouží k uložení webové stránky pro možnost pozdějšího zobrazení. Základní ověření funkčnosti modulu probíhalo pomocí sad testů.The goal of this bachelor thesis was to get acquainted with the principles of transmission, storage and re-visualisation of web traffic. The next part lied with the design and realization of the module for the reconstruction and exporting of the web traffic contents. This module allows to assemble the websites acquired from the captured web communication. It also allows to visualize such websites. The outputs of the module are made through the archival format MAAF, which serves to store web pages for the option of later display. The basic validation of the module functionality was done using test sets.
Ownership of personal data in the Internet of Things
This article analyses, defines, and refines the concepts of ownership and personal data to explore their
compatibility in the context of EU law. It critically examines the traditional dividing line between
personal and non-personal data and argues for a strict conceptual separation of personal data from
personal information. The article also considers whether, and to what extent, the concept of ownership
can be applied to personal data in the context of the Internet of Things (IoT). This consideration is
framed around two main approaches shaping all ownership theories: a bottom-up and top-down
approach. Via these dual lenses, the article reviews existing debates relating to four elements supporting
introduction of ownership of personal data, namely the elements of control, protection, valuation, and
allocation of personal data. It then explores the explanatory advantages and disadvantages of the two
approaches in relation to each of these elements as well as to ownership of personal data in IoT at large.
Lastly, the article outlines a revised approach to ownership of personal data in IoT that may serve as a
blueprint for future work in this area and inform regulatory and policy debates
Can hydrodynamic contact line paradox be solved by evaporation--condensation?
We investigate a possibility to regularize the hydrodynamic contact line
singularity in the configuration of partial wetting (liquid wedge on a solid
substrate) via evaporation-condensation, when an inert gas is present in the
atmosphere above the liquid. The no-slip condition is imposed at the
solid-liquid interface and the system is assumed to be isothermal. The mass
exchange dynamics is controlled by vapor diffusion in the inert gas and
interfacial kinetic resistance. The coupling between the liquid meniscus
curvature and mass exchange is provided by the Kelvin effect. The atmosphere is
saturated and the substrate moves at a steady velocity with respect to the
liquid wedge. A multi-scale analysis is performed. The liquid dynamics
description in the phase-change-controlled microregion and visco-capillary
intermediate region is based on the lubrication equations. The vapor diffusion
is considered in the gas phase. It is shown that from the mathematical point of
view, the phase exchange relieves the contact line singularity. The liquid mass
is conserved: evaporation existing on a part of the meniscus and condensation
occurring over another part compensate exactly each other. However, numerical
estimations carried out for three common fluids (ethanol, water and glycerol)
at the ambient conditions show that the characteristic length scales are tiny
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