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Analytical methods for measurement error estimation in survey data
Chylíková, Johana ; Vinopal, Jiří (advisor) ; Kreidl, Martin (referee) ; Buriánek, Jiří (referee)
Analytical methods for measurement error estimation in survey data This dissertation aims at the domain of measurement error in social science survey data. To conceptualize and estimate measurement errors it employs the analytical and theoretical framework that stems from the analytical method of structural equation modeling (SEM) and Classical Test Theory (CTT), extended with the component of the systematic measurement error. This thesis has two goals that may contribute to development and extension of Czech social science methodology. The first goal is to illustrate methods of measurement error estimation, which has not been used for analysis of Czech data yet, and to point out to some problematical aspects of these methods. The second goal is to employ presented methods to obtain new findings regarding the quality of data from Czech surveys. The dissertation presents three empirical studies, each of which uses one of the methods defined within the presented theoretical and analytical framework. First study presents an analysis of reliability of measurement with the Quasi Simplex Model (QSM). It illustrates how to use the model and brings optimistic results regarding the reliability of the Czech EU SILC panel data. In the second study the confirmatory factor analysis model, operationally called...
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Motion of a body in a fluid with pressure dependent viscosity
Sláčík, Stanislav ; Průša, Vít (advisor) ; Süli, Endré (referee)
A lot of technologically relevant incompressible fluids exhibit a substantial variaton of viscosity with the pressure;a falling cylinder viscometer is frequently used for the measurements, determining the viscosity indirectly from the time it takes the sinker to fall a given distance. The relation between the sinker fall velocity and the fluid viscosity is, however, derived under the constant viscosity assumption. The objective of the present thesis is to perform a numerical simulation of the viscometric experiment, assuming an explicit form of the pressure-viscosity dependence and realistic parameter values and to quantitatively assess the difference in body motion to the Navier- Stokes model. The computational method proposed, handling both the nonlinear constitutive relation and the body motion, was tested on simple problems with analytical solutions. The semianalytical relation for the Navier-Stokes model, also re-derived here, is compared to the computational results.The validity of the assumptions used in the theoretical derivation, based on the results of the numerical simulation, is discussed regarding the geometry of the viscometer. Powered by TCPDF (www.tcpdf.org)
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The Optimal Accuracy of Measurement Assurance in Accordance with Metrological Confirmation
Frank, Petr ; Kocman, Karel (referee) ; Nenadál, Jaroslav (referee) ; Hruška, Karel (advisor)
This thesis deals with the evaluation of accuracy of measurement and achieving the required accuracy level. This includes global analysis of the uncertainty evaluation, the calibration interval design and the creation of confirmation system. Basis of this work is in identification of all possible problems, which may occur during evaluation of accuracy and achieving the required accuracy level. The analysis is followed by suggested solutions for identified problems. It means namely the selection of probability distribution in case of uncertainty type A, evaluation of degrees of freedom in case of uncertainty type B, nonlinear correlation of input values, evaluation of coverage factor, the choice of method for calibration interval design and the procedure for meeting all metrological confirmation requirements. The last part of the thesis is practical measurement and result evaluation in the field of surge protection devices. This chapter demonstrates conclusions from the syntactical part.
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Expressing uncertainty of accurate lenght measurement II
Šrámek, Jan ; Pernikář, Jiří (referee) ; Koška, Petr (advisor)
This diploma thesis is supposed to inform readers interested in the distance measurements uncertainty on practical issues connected with the solving of these troubles when utilising a frequently used calibration method - the Tesa NPL measure instrument. This measuring was implemented by the Czech Metrologic Institute, where the author works; therefore he could take advantage of his rich experience as well as experience of his superiors and colleagues. The author regards the national metrological institute (CMI) as a sufficient guarantee for the hereinafter presented materials, both regarding the professional qualification and from the perspective of formal rightness of this thesis.
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Uncertainties Analyze of Indirect Measurement
Fišr, Petr ; Janečka, Jan (referee) ; Vdoleček, František (advisor)
This diploma thesis is engaged with problems of expressing measurement uncertainty especially for indirect measurements. This issue is shown here on a few simple examples. Part of this work is a calculation module for the determination of measurement uncertainties, applied to the role of the laboratory 'measurement of the flow orifice.
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BER Meter for Video Signals
Šimoník, Petr ; Frýza, Tomáš (referee) ; Říčný, Václav (advisor)
The diplomma thesis is dealing with possibilities of Signal to noise ratio measurement by method, which is based on direct measurement. It is chosen the most suitable method – signal and noise separation to two different parallel signal branches, where is measured signal strength in one branch and root mean square value in the other. The thesis is consisted of a concept of detail block scheme of Signal to noise ratio meter, which was designed in terms of theoretical knowledge. Particular functional blocks were circuit-designed, the active and passive parts were chosen and their function were described. There were made simulation and displayed input and output time flows. There is designed the whole connection of engineered Signal to noise ratio meter in the last part of my thesis. The double-sided board of printed circuit is contained too. It was created simple programme for supervisor micro-processor. Thereby were constructed complete bases for realization.
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The expression of the accuracy of the gauge and measurement
Svobodová, Helena ; Koška, Petr (referee) ; Pernikář, Jiří (advisor)
The bachelor thesis deals with the issue of measurement, accuracy of measuring instruments and their expressing. It outlines the legislative basis of metrology in the Czech Republic and interprets the definitions of basic terms used in metrology. These definitions are listed in the new edition of International dictionary of metrology (VIM 3:2007). It specifies and exemplifies measurement errors and presents possibilities of their elimination. Further, it describes a simple way of measurement uncertainty determination. The aim of this thesis is to explain the issue in a way that it is understandable and can be applicable for the common metrology practice.
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Uncertainties of Accurate Length Measurement
Šrámek, Jan ; Brno), Václav Duchoň (ČMI (referee) ; Vdoleček, František (advisor)
This diploma thesis is supposed to inform readers interested in the distance measurements un-certainty on practical issues connected with the solving of these troubles when utilising a frequently used calibration method - the SIP distance meter. This measuring was implemented by the Czech Metrologic Institute, where the author works; therefore he could take advantage of his rich experience as well as experience of his superiors and colleagues. The author regards the national metrological institute (ČMI) as a sufficient guarantee for the hereinafter presented materials, both regarding the professional qualification and from the perspective of formal rightness of this thesis.
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