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Lightning-Related Electromagnetic Wave Phenomena in the Earth's Magnetosphere
Záhlava, Jan ; Němec, František (advisor)
Title: Lightning-Related Electromagnetic Wave Phenomena in the Earth's Magnetosphere Author: Jan Záhlava Department: Department of Surface and Plasma Physics Supervisor: doc. RNDr. František Němec, PhD., Department of Surface and Plasma Physics Abstract: The thesis focuses on lightning-related electromagnetic wave phenomena observed by spacecraft in the Earth's inner magnetosphere. Two different approaches are used to identify the frequency and spatial extent where lightning generated emissions significantly contribute to the overall wave intensity. First, whistler detections onboard the DEMETER spacecraft are used to sort the measurements according to the whistler activity. Second, we use a geographic distribution of lightning activity and analyze a dependence of the overall wave intensity on geomagnetic longitude. We show that, especially during the night, the overall wave intensity observed in the plasmasphere is well correlated with lightning activity. The other focus of the study is on special electromagnetic wave events consisting of alternating frequency bands of enhanced and reduced wave intensity formed in the ionosphere due to lightning. We analyze their occurrence and parameters, and we suggest a possible mechanism of their formation. Keywords: lightning, waves in plasma, whistlers, plasmasphere
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Kindergarten in Jihlava
Vystrčil, Jan ; Straka,, Bohumil (referee) ; Šuhajda, Karel (advisor)
In diploma thesis is elaborated project documentation for the construction of an building of kindergarten. The building is situated in peryphery of Jihlava city. The building is two-storey kindergarten building with a basement. There aure two classes for children 3 - 6 years old in the building. In diploma thesis is elaborated architect-building solutions, building – construction solutions, fire safety solutions and physics qualities of constructions.
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Lightning-Related Electromagnetic Wave Phenomena in the Earth's Magnetosphere
Záhlava, Jan ; Němec, František (advisor) ; Chum, Jaroslav (referee) ; Manninen, Jyrki (referee)
Title: Lightning-Related Electromagnetic Wave Phenomena in the Earth's Magnetosphere Author: Jan Záhlava Department: Department of Surface and Plasma Physics Supervisor: doc. RNDr. František Němec, PhD., Department of Surface and Plasma Physics Abstract: The thesis focuses on lightning-related electromagnetic wave phenomena observed by spacecraft in the Earth's inner magnetosphere. Two different approaches are used to identify the frequency and spatial extent where lightning generated emissions significantly contribute to the overall wave intensity. First, whistler detections onboard the DEMETER spacecraft are used to sort the measurements according to the whistler activity. Second, we use a geographic distribution of lightning activity and analyze a dependence of the overall wave intensity on geomagnetic longitude. We show that, especially during the night, the overall wave intensity observed in the plasmasphere is well correlated with lightning activity. The other focus of the study is on special electromagnetic wave events consisting of alternating frequency bands of enhanced and reduced wave intensity formed in the ionosphere due to lightning. We analyze their occurrence and parameters, and we suggest a possible mechanism of their formation. Keywords: lightning, waves in plasma, whistlers, plasmasphere
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Numerical Analysis of the Lightning on Small Aircraft
Krutílek, David
This paper deals with numerical analysis of lightning stroke effects on aircraft. Computations are implemented by the use of the time-domain solver (FIT). Attention is turned to a simple model of a composite nose part of the airplane EV-55. The analysis of the model itself is performed for two fundamentally different basic conceptions of a possible protection against direct effects of lightning.
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VC5 and Vision Designer platform visual system
Popovský, Pavel ; Janáková, Ilona (referee) ; Honec, Peter (advisor)
For the purpose of an future machine vision system development in Tyco Electronics Czech s.r.o. I have developed Cognex Designer template. Template will serve as a flexible basis for further development of camera applications on the Cognex VC5 industrial computer. The functionality of the program template has been successfully verified by modifying it to a particular application of the laboratory manual station used to measure the parameters of the manufactured connectors. A camera with lens and lightning was chosen and installed on the station. DIO communication was put into operation between VC5 and PLC system. The application has been calibrated and verified as a measurement system using MSA Type I and Capability study standard methods.
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Severe lightning activity over the Czech republic
Uhlíková, Tereza ; Novák, Petr (advisor) ; Kyznarová, Hana (referee)
This work comprises an introduction to study of lightning and presents data about daily amount of lightning flashes over the Czech Republic (CR) in period 2002-2012. For selected days in this period, there are introduced and examined some meteorological characteristics. There are presented an evolution of lightning discharges and contemporary options for lightning detection which contain ground-based systems and satellites systems. Main advantage of ground-based systems are location accuracy <1 km and additional information which could be provided about every single stroke which is e. g. polarity or peak current. The benefit of satellite lightning detection is the large covera- ge which is useful for a global view of lightning activity on the Earth. After that, the general climatology of lightning in the world is introduced. The land-ocean contrast in lightning activity is presented (lightning activity over land is up to two orders higher than over the ocean). There is also information about maximum amount of flashes over equatorial Africa. The hypothesis explaining the land-ocean contrast in lightning activity and African maximum are included. Climatological charakteristics of lightning in selec- ted European countries are mentioned in the last section. In analytical part of the work, single years...
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Investigation of lightning-generated elecromagnetic waves in a broad frequency range
Fišer, Jiří ; Santolík, Ondřej (advisor) ; Němec, František (referee)
In this work I present a study dedicated to the penetration of whistler- mode waves to the ionosphere. An algorithm of automatic detection of whist- lers in spectrograms computed from the data measured on the DEMETER sa- tellite is described. A method of causative lightning detected by the EUCLID lightning detection network assignment to a detected whistlers is described. Results of statistical study dedicated to relationship between the detected whistlers and assigned causative lightning. Based on the proccessing of data from 364 passes of the DEMETER satellite over monitored area is shown, that mean whistler amplitude decreases with distance between the causative lightning, increses with causative lightning current and in the evening is ap- proximately three times higher than in the morning. A study dedicated to subprotonospheric whistlers is presented. We found, that subprotonospheric whistler causative lightnings currents are very high compared to that of usual 0+ whistlers.
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Surge in electrical networks and protection of electrical devices against surge
EFFENBERK, Kryštof
The bachelor thesis is focused to problems with surge. Different kinds of surge are distinguished in the introduction. Specifically it deals with the atmospheric surge and switching surge. Further on it describes surge waves and their propagation along lines of low voltage. The next section is focused on blueprints of signal generator. In a later section the author moves to the basic level of surge protection and surge protection devices. Last part of the bachelor thesis researches place, where we can plant surge protection devices. It also explains the behavior of the surge waves at interfaces of different impedances.
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Design of Lightning Protection of Family House
Kovář, Zdeněk ; Bátora, Branislav (referee) ; Toman, Petr (advisor)
Bachelor´s thesis decribes the fundamental theory that is necessary for the proper design of the house from the damaging effects of lightning. The aim is to give a brief and comprehensive look into the issues. The first part of this thesis describes the emergence of lightning, adverse effects on protected and unprotected building and risk analysis. The second part presents the different types of protections. The following third part describes a brief overview of the history of standards and regulations and overview of standards currently valid in the Czech Republic. The last part of the thesis deals with the creation of my own proposal for lightning protection for the chosen fictitious family house.
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