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Multicomponent wave measurements performed by the DEMETER spacecraft
Kotková, Marie ; Němec, František (advisor) ; Chum, Jaroslav (referee)
We analyze data from wave measurements performed by the DEMETER spacecraft in the frequency range up to 1250 Hz. We investigate the dependence of wave parameters on daytime, geomagnetic latitude, geomagnetic activity, and season, both globally and in the geomagnetic longitude range corresponding to America, where there is a substantial seasonal variation in lightning occurrence. We show that, during the day, there is generally a prevalence of waves propagating from larger radial distances, i.e. generated by plasma instabilities; during the night, the situation is opposite, indicating a prevalence of waves generated by lightning activity. The difference in wave vector directions detected above America is the largest between winter days during elevated geomagnetic activity and summer nights during low geomagnetic activity. We use the typical wave vector directions to trace back the tentative source region of the waves detected during the daytime half-orbits.
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Verification of empirical models of magnetic field around Earth
Kotková, Marie ; Němec, František (advisor) ; Výbošťoková, Tatiana (referee)
The objective of this thesis is to evaluate the accuracy of two frequently used models of magnetic field within Earth's magnetosphere (Tsyganenko 1989, 1996). In order to do this, we use vector magnetic data from four satellites of the Cluster II mission, collected between 2001-2014 and covering almost the whole region of the Earth's inner magne- tosphere at radial distances from 2 to 20 Earth radii. We compare model predictions with spacecraft data and evaluate the spatial dependence of the magnitude differences and angular deviations. Furthermore, we compare model locations of the min-B equator with the locations determined using the four-point measurements, and we study the de- pendence of the respective latitudinal deviations on the level of geomagnetic activity. We show that, although both models are very well correlated with satellite data, the newer model is systematically more accurate. At the same time, we show that the accuracy of both models decreases significantly during the periods of increased geomagnetic activity. 1
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Cash flows presented by state organizational units in the Czech Republic
Kotková, Marie ; Nováková, Štěpánka (advisor) ; Zelenka, Vladimír (referee) ; Steidlová, Jaromíra (referee)
This thesis is focused on the public sector and deals with one of the new financial statements presented by state organizational units, the cash flow statement, which these state organizational units prepared for the first time for the financial year 2011. The main objective of the thesis is to analyze in detail the quality of these cash flow statements prepared by individual administrators of the state budget chapters and passed for the first time to the Central system of state accounting information. The thesis also presents an evaluation of the quality of the Czech legislative regulation of the cash flows statement in relation to state organizational units and it compares the legislative regulation in the period between 2011 and 2012. An integral part of the thesis is creating theoretical models suitable for the preparation of the cash flow statement. The first model is based on the relationship among particular items of the accounting and financial statements and the second model is based on the transformed data from the statement for evaluation of the state budget implementation.
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