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Forward and Inverse Modeling of Planetary Gravity and Topography
Pauer, Martin ; Čadek, Ondřej (advisor) ; Martinec, Zdeněk (referee) ; Novák, Pavel (referee)
Title: Forward and Inverse Modeling of Planetary Gravity and Topography Author: Martin Pauer Department/Institute: Department of Geophysics MFF UK Supervisor of the doctoral thesis: Doc. RNDr. Ondřej Čadek, CSc., Department of Geophysics MFF UK Abstract: The aim of this work was to investigate various mechanisms compensating the observed planetary topography - crustal isostasy, elastic support and dynamic support caused by mantle flow. The investigated models were applied to three different planetary problems. Firstly we applied dynamic compensation model to explain today large-scale gravity and topography fields of Venus and investigate its mantle viscosity structure. The results seem to support not only models with constant viscosity structure but also a model with a stiff lithosphere and a gradual increase of viscosity toward a core. In the second paper several crust compensation models were employed to estimate the density of the Martian southern highlands crust. Since the used methods depends differently on crustal density changes, we were able to provide some constraints on the maximum density of the studied region. In the third application, the strength of a possible ocean floor gravity signal of Jupiter's moon Europa was studied. It turned out that if the long wavelength topography reaches height at...
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Gerundial and ing-participial clauses in written and spoken academic texts
Pajmová, Klára ; Malá, Markéta (advisor) ; Šaldová, Pavlína (referee)
This Master's thesis deals with the gerund and -ing participial clauses in written and spoken academic texts. The theoretical part defines the academic discourse and non-finite verb forms. Gerund and -ing participial constructions are further described regarding their forms and syntactic functions. The sources used for the research part are two corpora of contemporary academic British English: BASE and BAWE. BASE corpus contains transcripts of academic lectures. BAWE corpus is a collection of university-level students' writings. Both corpora contain texts from four different genres and moreover students' assignments are divided into four levels of study. For the purpose of the research part of our thesis, only the genre "Arts and Humanities" and the highest level of study will be taken into account. The practical part analyses the frequency of gerund and -ing participial clauses, frequency of verbs occurring in these constructions and collocations of these verbs. A detailed analysis aims at studying 100 sentences from written texts and 100 sentences from academic lectures. This sample is examined regarding the internal structure of each non-finite clause and its syntactic function. The final section summarizes the results or our research.
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Methods of study of porosity of granitic rocks in relation to rock fabric
Votavová, Klára ; Přikryl, Richard (advisor) ; Krutilová, Kateřina (referee)
This bachelor thesis focuses on granitic rocks, which are often used as a building material. Granite are generally rocks with very low porosity, which can be modified (augmented) due to e.g. weathering processes. Increase of porosity is accompanied with deterioration of other physical parameters and decrease of durability. The thesis focuses, after introducing basic petrographical and petrogenetic characteristics of granitic rocks, on the definition of porosity as a physical property, and on various methods used for its determination. Next part of the thesis discusses some case studies which underpin the significance of porosity of granitic rocks by either using combination of several methods, or by using unconventional ones. According to available data, study of porosity and its relationship to rock fabric should be performed by combining several methods of study, encompassing simple petrophysical determination of open and bulk porosities, and microscopic methods allowing for visualisation of pore space - mineral grains relationships. These can be accompanied with less common method of multidirectional ultrasonic sounding allowing for determination of spatial distribution of microcracks present in granitic rocks.
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Methods of study of porosity of granitic rocks in relation to rock fabric
Votavová, Klára ; Přikryl, Richard (advisor) ; Krutilová, Kateřina (referee)
This bachelor thesis focuses on the problem of porosity of granites. The introductory part of the thesis describes granites, their origin, and classification. Specific concern is given to granites as building materials; therefore factors influencing the quality and durability of building stone are mentioned. Porosity of granites can be observed by several different methods. However, none of the methods provides accurate information on present pores from all points of view. From the methods used, mercury porosimentry performed under laboratory conditions seems to be one of the most effective methods. Other effective approaches are microscopic techniques, such as a scanning electron microscopy with energy dispersive spectrometry and/or optical microscopy. Generally, it is suggested to combine several methods to combine information on the volume and distribution of pores with their shape and size.
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Forward and Inverse Modeling of Planetary Gravity and Topography
Pauer, Martin ; Čadek, Ondřej (advisor) ; Martinec, Zdeněk (referee) ; Novák, Pavel (referee)
Title: Forward and Inverse Modeling of Planetary Gravity and Topography Author: Martin Pauer Department/Institute: Department of Geophysics MFF UK Supervisor of the doctoral thesis: Doc. RNDr. Ondřej Čadek, CSc., Department of Geophysics MFF UK Abstract: The aim of this work was to investigate various mechanisms compensating the observed planetary topography - crustal isostasy, elastic support and dynamic support caused by mantle flow. The investigated models were applied to three different planetary problems. Firstly we applied dynamic compensation model to explain today large-scale gravity and topography fields of Venus and investigate its mantle viscosity structure. The results seem to support not only models with constant viscosity structure but also a model with a stiff lithosphere and a gradual increase of viscosity toward a core. In the second paper several crust compensation models were employed to estimate the density of the Martian southern highlands crust. Since the used methods depends differently on crustal density changes, we were able to provide some constraints on the maximum density of the studied region. In the third application, the strength of a possible ocean floor gravity signal of Jupiter's moon Europa was studied. It turned out that if the long wavelength topography reaches height at...
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Gerundial and ing-participial clauses in written and spoken academic texts
Pajmová, Klára ; Malá, Markéta (advisor) ; Šaldová, Pavlína (referee)
This Master's thesis deals with the gerund and -ing participial clauses in written and spoken academic texts. The theoretical part defines the academic discourse and non-finite verb forms. Gerund and -ing participial constructions are further described regarding their forms and syntactic functions. The sources used for the research part are two corpora of contemporary academic British English: BASE and BAWE. BASE corpus contains transcripts of academic lectures. BAWE corpus is a collection of university-level students' writings. Both corpora contain texts from four different genres and moreover students' assignments are divided into four levels of study. For the purpose of the research part of our thesis, only the genre "Arts and Humanities" and the highest level of study will be taken into account. The practical part analyses the frequency of gerund and -ing participial clauses, frequency of verbs occurring in these constructions and collocations of these verbs. A detailed analysis aims at studying 100 sentences from written texts and 100 sentences from academic lectures. This sample is examined regarding the internal structure of each non-finite clause and its syntactic function. The final section summarizes the results or our research.
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