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Farms for rearing pigs in terms of noise level in the neighborhood.
PETRÁŠEK, Tomáš
The bachelor thesis is aimed at assessing the farm for rearing pigs in terms of noise level in the neighborhood. The main objective was to measure the noise during the working operation at different places of the selected object, to process the collected data, to calculate the equivalent noise level and then evaluate the results of the work. On the basis of measured and assessed values is apparent that the noise pollution of the examined object has no effect on its neighborhood and therefore it is not necessary to propose any specific actions to improve the current situation.
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Rerating on the low voltage devices with a thermal trip unit
Trubák, Vojtěch ; Valenta, Jiří (referee) ; Dostál, Lukáš (advisor)
This work is about bimetal trip unit used in circuit breakers. It focuses on how ambient temperature affects function of this tripping unit. In second chapter of this work, there are described thermal and dynamic effects of electric current. You can find there equations for calculation of temperature rise caused by electric current, its max temperature change and its process, also equations describing force, caused by electric current. In third chapter is short introduction of circuit breakers. There is description of their function, classification and construction. Finally there is description of residual current device. Fourth chapter of this work is focused on bimetals. There is described their function principle, ways of manufacture, used materials and its tripping characteristic. In fifth chapter, the circuit breaker 3VA12 is introduced, its electrical characteristics and its applications. Also, there is described principal of bimetal application as thermal trip unit. Sixth chapter is about procedure used to create model in CAD program Solidworks. You can find there individual pieces of current path and its addons connected together and forming model of circuit breaker. There are also showed modifications of the model, using thermal and conduction resistances. Last chapter is dedicated to results of rerating. There is final table showing correction koeficients of rated operational current and their comparison to real ones.
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The effect of atorvastatine on expression of selected markers of vascular endothel
Rusnoková, Jana ; Kopecký, Martin (referee) ; Nachtigal, Petr (advisor)
Atherosclerosis, or sclerosis of arteries, is a degenerative disease of arteries. Sometimes it is called "the disease of 20th century". ApoE/LDL - receptor double knockout mice represent a new animal model for study of atherogenesis, which is characterized by severe hyperlipidaemia and atherosclerosis. Statins (or competitive inhibitors 3-hydroxyl-3-methyl-glutaryl-coenzym A-reductase) currently belong to the most efficient and the most useful hypolipidemic drugs for all over the world. They decrease mainly levels of total cholesterol and LDL cholesterol. The aim of this thesis was to describe the expression of eNOS in atherosclerotic plaques in apoE/LDLreceptor deficient mice. Moreover, we wanted to atorvastatin effects on its expression in the vessel wall. ApoE/LDLR-deficient mice on were subdivided into two groups. The control group of animals was fed with the cholesterol rich diet. The same cholesterol rich diet was used in ATV group, where atorvastatin was added to the atherogenic diet at the dosage of 50 mg/kg per day. The results of this thesis confirmed the expression eNOS in aortic endothelium in both control and atorvastatin treated mice. Atorvastatin treatment resulted in a strong hypolipidemic and antiatherogenic effect. Stereological analysis demonstrated that atorvastatin...
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Mapping of photoelectric effects in semiinsulating CdTe
Korcsmáros, Gabriel ; Franc, Jan (advisor) ; Sedláková, Vlasta (referee)
The main advantage of CdTe and CdZnTe materials is the fact that the envolving elements have big atomic numbers and density, this is reflected in a high absortion coeficient. which is a very preferent feature. It enables to detect low energy photons and means high quantum effiency. Mentioned features can be managed at room temperature, therefore these matrials are very perspective for gamma-ray detection. For the detector sensitivity is important to have low dark current, and to have big fold of carrier lifetime and mobility. These properties can be reached in some parts of the materials. Finding the causes of these quality degradation and the signal loss are the main priorities of the exploration. The main problem is the quality of these materials, the inhomogenities are decreasing the detection capability. In this work we will study lux-amper characteristics and analyze photoconductivity maps to better our understanding how inhomogenities influence these parameters. Two main methods will be used, contactless and contact methods with Au applied as contact metal. These maps will be compared. Photoconductivity maps can increase our understanding of charge transport inside the material.
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Protection against noise and vibrations from the legal point of view
Pavelková, Kamila ; Damohorský, Milan (advisor) ; Franková, Martina (referee)
- aj Excessive noise occupies a number of factors threatening our environment is an increasingly important place. It does not even reach extremely high levels, yet a negative effect on mental performance, impairs mental well-being affects the quality of sleep, or cause annoyance, because a person is forced to perceive unwanted sounds. The most important and geographically most widespread source of noise is traffic. The largest share of the total noise in the Czech Republic has the vehicular traffic, the smaller share of the load is noise from rail and air transportation. The subject of my thesis is the protection against noise, especially in outside - employment environment, which is currently considered as a very significant source of danger to human health and environment. Introductory chapter no. 2 contains the substance of the basic concepts - sound, noise, emissions and pollution of noise, vibration, further indicates the negative effects of noise on human health and suggests possible measures to reduce noise. Chapter no. 3 is devoted to European legislation, protection against noise and vibration. First, briefly discusses the process of European integration, the main objectives and EU institutions. Further defines the sources of EU law and the main objectives and principles of European...
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Global Population Problem
Papežová, Zuzana ; Jeníček, Vladimír (advisor) ; Janković, Vukica (referee)
Bachelor thesis titled Global Population Problem is focused on a group of global problems, which mainly arises from the adverse demographic development on Earth. The aim of this work is to describe the basic demographic trends affecting the formation and existence of the global population problem. It also gives evaluation and suggestions of current and future solutions to this problem. Characterization of demographic indicators and their changes over time with an emphasis on both the average and extreme values and analysis of solutions of selected sub-part of the problem were used as a method. Based on the information, it is possible to identify the main problems and analyze possible solutions. The first problem is the rapid population growth, when the number of people on the planet could more than double by the end of the century. Furthermore, the asymmetry of this growth, with the largest share of the population explosion to the poorest regions, whose young age structure prevents the stabilization of population growth in short term. Also the European continent is affected by the population aging, which causes the gradual extinction of the local peoples. There is no comprehensive solution to these problems. Nevertheless, partial steps will gradually improve the situation and may achieve some improvements.
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Database of Whistler-mode Chorus in the Equatorial Plane
Macúšová, E. ; Santolík, Ondřej
Chorus emission is one of the most intense electromagnetic waves. Its source region is localised close to the geomagnetic equatorial plane within a few degrees. We present a unique database of whistler-mode chorus/hiss events obtained from the complete data set of wave measurements provided by the STAFF/DWP wave instrument on board TC-1 spacecraft. The TC-1 is one of two Earth orbiting satellites from the Double Star mission and it orbits close to the equatorial plane. Some instruments onboard both spacecraft are identical to those currently flying on the four Cluster spacecraft. The data base covers the full operational period of the spacecraft, between January 2004 and October 2007. All the events have been visually selected from the onboard-analyzed time-frequency spectrograms of magnetic search-coil measurements below 4 kHz.
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Inverse values of EEG signal power in joint EEG-fMRI analysis
Sanetrníková, Dominika ; Kolář, Radim (referee) ; Labounek, René (advisor)
The first part of this thesis summarizes the basic theory of brain activity measurement using the BOLD signal and scalp EEG, the effect of noise phenomena in the data and its suppression, the merger of the fusion of the measured data using the general linear model and the current implementation of computational algorithms in the software library EEG Regressor Builder 1.0. Within the own solution of this thesis, the changes of the software library to version 1.1 were realized according to the requirements of the bachelor thesis. The hypothesis that temporal changes of the EEG relative band power (20 - 40Hz) has the same spatial correlates with the BOLD signal as the inverse power in the frequency range 0-12Hz. The hypothesis was rejected based on the calculation of similarity criterions between 3D activation maps for different parameter settings of the joint analysis calculations. As an appropriate criterions were chosen the correlation coefficient and the cosine criterion. The Euclidean distance was proved to be unfit. Also it was proved the inverse power value of EEG signal in the given frequency band brings to the common EEG-fMRI analysis an anti-correlated signal to the normal absolute power in the same frequency band. Furthermore the influence of regressors describing motion artifacts reduces the number of supra-thresholded voxels.
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Interferometric measurement system for cost effective e-beam writer
Řeřucha, Šimon ; Šarbort, Martin ; Lazar, Josef ; Číp, Ondřej
The reliability of nanometer track writing in the large scale chip manufacturing process depends mainly on a precise positioning of the e-beam writer moving stage. The laser interferometers are usually employed to control this positioning, but their complicated optical scheme leads to an expensive instrument which increases the e-beam writer’s manufacturing costs. We present a new design of an interferometric system useful in a currently developed cost effective e-beam writers. Our approach simplifies the optical scheme of known industrial interferometers and shifts the interference phase detection complexity from optical domain to the digital signal processing part. Besides the effective cost, the low number of optical components minimizes the total uncertainty of this measuring instrument. The scheme consists of a single wavelength DFB laser working at 1550 nm, one beam splitter, measuring and reference reflectors and one photo-detector at the interferometer output. The DFB laser is frequency modulated by slight changes of injection current while the interference intensity signal is processed synchronously. Our algorithm quantifies the phase as two sinusoidal waveforms with a phase offset equal to the quarter of the DFB laser wavelength. Besides the computation of these quadrature signals, the scale linearization techniques are used for an additional suppression of optical setup imperfections, noise and the residual amplitude modulation caused by the laser modulation. The stage position is calculated on basis of the DFB laser wavelength and the processed interference phase. To validate the precision and accuracy we have carried out a pilot experimental comparison with a reference interferometer over the 100 mm measurement range. The first tests promise only 2 nm deviation between simplified and the reference interferometer.
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Power side channel
Zapletal, Ondřej ; Mácha, Tomáš (referee) ; Martinásek, Zdeněk (advisor)
This thesis deals with side-channel cryptoanalysis. It is focused on power side-channel attack on cryptographic device. The microcontroller PIC is used as the cryptographic device. This microcontroller performs encryption through the symmetrical algorithm AES. For the purpose of simple and differential power analysis, we designed and constructed an experimental printed circuit board. The power consumption of the microcontroller PIC working with instruction AddRoundKey and SubBytes was scanned by a Tektronix CT-6 current probe. Data obtained by measuring were processed on the computer with relevant software and provided important information about the encryption key that was used.
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