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Mobile internet principles
Jehličková, Lenka ; Fencl, Josef (referee) ; Hanus, Stanislav (advisor)
Thesis concerns with mobile communications theory with focus on data transfer. In the introduction the history, the origin and individual mobile systems generations are described. It is followed by detailed description of second, third and fourth generation mobile systems. Frequency band allocation, signal processing, the system architecture itself, security management and basic features are also discussed. The GSM system is described together with individual data transmission types based on circuit switching – CSD and HSCSD and packet switching – GPRS and EDGE. For UMTS, FDD and TDD modes are listed as well as changes in individual releases, corresponding technologies and provided services. Next, there is the description of LTE and WiMAX systems, together with their improvements whose are part of the fourth generation of mobile systems. Last of the described systems is the still work in progress HAPS, also known as the system of stratospheric platforms. In the end important parameters are summarized and systems are compared with each other.
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Numerical model for the origin of magmatic textures and its application to the Fichtelgebirge/Smrčiny granite batholith
Špillar, Václav ; Dolejš, David (advisor) ; Ježek, Josef (referee) ; Žák, Jiří (referee)
Magmatic processes are major agents responsible for the formation and differentiation of the Earth's crust. In contrast to extensive efforts to improve understanding and utility of igneous geochemistry, physical processes of magma differentiation and solidification remain largely unclear. Large variability of igneous textures provides record of these processes and intensive parameters governing the crystallization. In this thesis, we develop quantitative methods, which allow us to better interpret igneous textures in the framework of physics of solidification. We have developed a new three-dimensional model of crystallization from one- component melt driven by homogeneous and heterogeneous nucleation and crystal growth. The predicted textures are quantitatively characterized by crystal size distributions, spatial distribution functions and parameters representing grain contact relationships. The model employs high resolution in a large volume simulation domain in order to produce statistically stable results. Our simulations, performed for various functional forms of nucleation and growth rates with respect to time, imply that (i) crystals are ordered (anti-clustered) on short length scales. This reflects that other crystals already have a finite size at the time of nucleation of younger crystal,...
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Numerical model for the origin of magmatic textures and its application to the Fichtelgebirge/Smrčiny granite batholith
Špillar, Václav ; Dolejš, David (advisor) ; Ježek, Josef (referee) ; Žák, Jiří (referee)
Magmatic processes are major agents responsible for the formation and differentiation of the Earth's crust. In contrast to extensive efforts to improve understanding and utility of igneous geochemistry, physical processes of magma differentiation and solidification remain largely unclear. Large variability of igneous textures provides record of these processes and intensive parameters governing the crystallization. In this thesis, we develop quantitative methods, which allow us to better interpret igneous textures in the framework of physics of solidification. We have developed a new three-dimensional model of crystallization from one- component melt driven by homogeneous and heterogeneous nucleation and crystal growth. The predicted textures are quantitatively characterized by crystal size distributions, spatial distribution functions and parameters representing grain contact relationships. The model employs high resolution in a large volume simulation domain in order to produce statistically stable results. Our simulations, performed for various functional forms of nucleation and growth rates with respect to time, imply that (i) crystals are ordered (anti-clustered) on short length scales. This reflects that other crystals already have a finite size at the time of nucleation of younger crystal,...
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Quantification of fabrics and magmatic textures of rhyolite extrusive domes
Hrudková, Kristýna ; Lexa, Ondrej (advisor) ; Závada, Prokop (referee)
Bubbles in rhyolites are being formed during ascension of rhyolite magma up to the surface. That is beacuse of decreasing content of dissolved water in melt. Stability of bubbles is kept constant because of their own internal pressure, which they are able to sustain for a long period. Some bubbles can occure after the fragmentation of magma in extrusive bodies on the surface. Bubbles created this way have very small size and they don't participate in fragmentation. In my thesis I'm dealing with internal structure of some rhyolite magmatic bodies and description of mechanisms of bubble formation. Furthermore I will concentrate on methods of quantification of the internal structure of extrusive domes, i.e. the AMS magnetic minerals population structure and texture analysis of rock incisions. Texture analysis was concentrated on some aspects, which could help us to assess the extent of distribution of bubbles in strips. In conclusion, I compare the results of these methods to evaluate the importance of individual structural elements for structural-geological interpretation. We investigated samples from extrusive rhyolite body, which are being formed during the gradual egression of magma on the surface. We were investigated bubbles and their realtions between each other by using several methods. On the...
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Mobile internet principles
Jehličková, Lenka ; Fencl, Josef (referee) ; Hanus, Stanislav (advisor)
Thesis concerns with mobile communications theory with focus on data transfer. In the introduction the history, the origin and individual mobile systems generations are described. It is followed by detailed description of second, third and fourth generation mobile systems. Frequency band allocation, signal processing, the system architecture itself, security management and basic features are also discussed. The GSM system is described together with individual data transmission types based on circuit switching – CSD and HSCSD and packet switching – GPRS and EDGE. For UMTS, FDD and TDD modes are listed as well as changes in individual releases, corresponding technologies and provided services. Next, there is the description of LTE and WiMAX systems, together with their improvements whose are part of the fourth generation of mobile systems. Last of the described systems is the still work in progress HAPS, also known as the system of stratospheric platforms. In the end important parameters are summarized and systems are compared with each other.
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